201
|
Yang DJ, Chang YY, Lin HW, Chen YC, Hsu SH, Lin JT. Inhibitory effect of litchi (Litchi chinensis Sonn.) flower on lipopolysaccharide-induced expression of proinflammatory mediators in RAW264.7 cells through NF-κB, ERK, and JAK2/STAT3 inactivation. J Agric Food Chem 2014; 62:3458-3465. [PMID: 24641487 DOI: 10.1021/jf5003705] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Litchi (Litchi chinensis Sonn.) flower ethanolic extract (LFEE) was found to contain five flavanoids [total amount, 102.73 ± 5.50 mg/g of dried extract (gDE)], nine phenolic acids (total amount, 60.31 ± 4.52 mg/gDE), and proanthocyanidin A2 (79.31 ± 2.95 mg/gDE). LFEE was used to evaluate the inhibitory effects on lipopolysaccharide- (LPS-) induced pro-inflammatory mediators in RAW264.7 cells. The results showed that LFEE treatment could suppress the expressions of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), the productions of nitric oxide (NO) and prostaglandin E2 (PGE2), and the secretions of pro-inflammatory cytokines [interleukin-1β (IL-1β), IL-6, and tumor necrosis factor α (TNF-α)] in the LPS-mediated RAW264.7 cells. The attenuation of LPS-induced inflammatory responses by LFEE was found to be closely related to the inhibition of the translocation of nuclear factor κB (NF-κB) p50/p65 subunits correlated with suppression of the activation of the inhibitor of κB kinase (IKK) α/β and downregulation of activation of extracellular signal-regulated kinase (ERK) and Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3).
Collapse
Affiliation(s)
- Deng-Jye Yang
- School of Health Diet and Industry Management, Chung Shan Medical University , and Department of Nutrition, Chung Shan Medical University Hospital , 110, Section 1, Jianguo N. Road, Taichung 402, Taiwan
| | | | | | | | | | | |
Collapse
|
202
|
Li W, Zhao Q, Deng W, Chen T, Liu M, Xie J. Mycobacterium tuberculosis Rv3402c enhances mycobacterial survival within macrophages and modulates the host pro-inflammatory cytokines production via NF-kappa B/ERK/p38 signaling. PLoS One 2014; 9:e94418. [PMID: 24722253 PMCID: PMC3983203 DOI: 10.1371/journal.pone.0094418] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2013] [Accepted: 03/16/2014] [Indexed: 11/23/2022] Open
Abstract
Intracellular survival plays a central role in the pathogenesis of Mycobacterium tuberculosis, a process which depends on an array of virulence factors to colonize and replicate within the host. The M. tuberculosis iron regulated open reading frame (ORF) rv3402c, encoding a conserved hypothetical protein, was shown to be up-regulated upon infection in both human and mice macrophages. To explore the function of this ORF, we heterologously expressed the rv3402c gene in the non-pathogenic fast-growing Mycobacterium smegmatis strain, and demonstrated that Rv3402c, a cell envelope-associated protein, was able to enhance the intracellular survival of recombinant M. smegmatis. Enhanced growth was not found to be the result of an increased resistance to intracellular stresses, as growth of the Rv3402c expressing strain was unaffected by iron depletion, H2O2 exposure, or acidic conditions. Colonization of macrophages by M. smegmatis expressing Rv3402c was associated with substantial cell death and significantly greater amount of TNF-α and IL-1β compared with controls. Rv3402c-induced TNF-α and IL-1β production was found to be mediated by NF-κB, ERK and p38 pathway in macrophages. In summary, our study suggests that Rv3402c delivered in a live M. smegmatis vehicle can modify the cytokines profile of macrophage, promote host cell death and enhance the persistence of mycobacterium within host cells.
Collapse
Affiliation(s)
- Wu Li
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Ministry of Education Eco-Environment of the Three Gorges Reservoir Region, School of Life Sciences, Southwest University, Chongqing, China
| | - Quanju Zhao
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Ministry of Education Eco-Environment of the Three Gorges Reservoir Region, School of Life Sciences, Southwest University, Chongqing, China
| | - Wanyan Deng
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Ministry of Education Eco-Environment of the Three Gorges Reservoir Region, School of Life Sciences, Southwest University, Chongqing, China
| | - Tian Chen
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Ministry of Education Eco-Environment of the Three Gorges Reservoir Region, School of Life Sciences, Southwest University, Chongqing, China
| | - Minqiang Liu
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Ministry of Education Eco-Environment of the Three Gorges Reservoir Region, School of Life Sciences, Southwest University, Chongqing, China
| | - Jianping Xie
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Ministry of Education Eco-Environment of the Three Gorges Reservoir Region, School of Life Sciences, Southwest University, Chongqing, China
- * E-mail:
| |
Collapse
|
203
|
Zheng XX, Zhang RS, Zhou YJ, Wang JG. [Role of ERK/FoxO3a signal axis in inhibitory effect of vitexin 1 (VB-1) in HepG2 cell proliferation]. Zhongguo Zhong Yao Za Zhi 2014; 39:1276-1279. [PMID: 25011268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
OBJECTIVE To investigate whether the ERK/FoxO3a signal axis could induce the inhibitory effect of vitexin 1 (VB-1) in HepG2 cell proliferation. METHOD The MTT method was adopted to observe the effect of different concentrations of VB-1 on human hepatoma carcinoma cell line HepG2 and immortalized human embryo liver cell line L-02. The cell growth was assessed by the clone formation assay. The protein phosphorylation levels of ERK1/2 and FoxO3a were measured by the western blot. RESULT VB-1 inhibited the viability of HepG2 cell line in a concentration-dependent manner, with a weak effect on L-02 cell line. VB-1 could effectively inhibit the anchorage-dependent growth of HepG2 cells, and reduce the expression levels of pERK1/2 and pFoxO3a in a concentration-dependent manner. MEK1/2 inhibitor PD98059 could enhance VB-1' s effect in inhibiting HepG2 cell proliferation and ERK1/2, FoxO3a phosphorylation. CONCLUSION VB-1 inhibits the proliferative activity of hepatoma carcinoma cell line HepG2 by blocking the ERK/FoxO3a signal axis.
Collapse
|
204
|
Shen Z, Shao XM, Fang F, Sun J, Fang JF, Fang JQ. [Effect of mild and strong manual acupuncture stimulation of "Huantiao" (GB 30) on mechanical pain thresholds and extracellular signal-regulated kinase protein expression in spinal dorsal horns in rats with neuropathic mirror-image pain]. Zhen Ci Yan Jiu 2014; 39:106-111. [PMID: 24818493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
OBJECTIVE To observe the effect of different intensities of manual acupuncture (MA) stimulation on mechanical pain thresholds (PTs) and the expression of phosphorylated extracellular signal-regulated kinases (p-ERK) in lumbar spinal dorsal horn regions in rats with neuropathic mirror-image pain, so as to explore its mechanisms underlying analgesia. METHODS Forty male SD rats were equally and randomly divided into control, spinal nerve ligation (SNL) model, mild MA-stimulation, and strong MA-stimulation groups. Neuropathological pain model was established by ligature of the spinal nerve (L 5). Three days after the SNL, bilateral "Huantiao" (GB 30) were stimulated by rotating the thin (0.22 mm x 13 mm) or thick (0.3 mm x 13 mm) filiform needles at a frequencies of 60 times/min or 180 times/min and at an angle of 180 degrees or 360 degrees for 2 min for rats in the mild and strong MA-stimulation groups, respectively, followed by remaining the needle in place for 30 min. The mechanical PTs were measured before and after SNL. The expression of p-ERK protein in bilateral dorsal horn regions of the lumbar spinal cord (L4- L 6) was detected by Western blot. RESULTS In comparison with the control group, the mechanical PTs were significantly decreased beginning from the 3rd day on after SNL on the affected side and from the 7th day on after SNL on the healthy hindpaw (P < 0.05), simultaneously, p-ERK protein expression levels of dorsal horn regions on both sides of the spinal cord were considerably up-regulated on the 12th day (P < 0.05). Compared with the model group, the PTs of the affected hindpaw and the healthy hindpaw were significantly increased on the 7th and 12th day in the strong MA-stimulation group (P < 0.05, P < 0.01), whereas pERK expression levels in the bilateral spinal dorsal horn regions were obviously down-regulated in the strong MA-stimulation group (P < 0.05). No significant differences were found between the model and mild MA-stimulation groups in the PTs of bilateral hindpaws and p-ERK expression levels of the bilateral spinal dorsal horn regions (P > 0.05) except the PTs of the healthy hindpaw on 7th day (P < 0.05). CONCLUSION Strong MA-stimulation can alleviate neuropathic mirror-image pain in SNL rats, which is closely related to its effect in down-regulating the expression of p-ERK in the bilateral spinal dorsal horn regions.
Collapse
|
205
|
Woodson EN, Anderson MS, Loftus MS, Kedes DH. Progressive accumulation of activated ERK2 within highly stable ORF45-containing nuclear complexes promotes lytic gammaherpesvirus infection. PLoS Pathog 2014; 10:e1004066. [PMID: 24722398 PMCID: PMC3983062 DOI: 10.1371/journal.ppat.1004066] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2013] [Accepted: 02/27/2014] [Indexed: 11/19/2022] Open
Abstract
De novo infection with the gammaherpesvirus Rhesus monkey rhadinovirus (RRV), a close homolog of the human oncogenic pathogen, Kaposi's sarcoma-associated herpesvirus (KSHV), led to persistent activation of the MEK/ERK pathway and increasing nuclear accumulation of pERK2 complexed with the RRV protein, ORF45 (R45) and cellular RSK. We have previously shown that both lytic gene expression and virion production are dependent on the activation of ERK [1]. Using confocal microscopy, sequential pull-down assays and FRET analyses, we have demonstrated that pERK2-R45-RSK2 complexes were restricted to the nucleus but that the activated ERK retained its ability to phosphorylate nuclear substrates throughout infection. Furthermore, even with pharmacologic inhibition of MEK beginning at 48 h p.i., pERK2 but not pERK1, remained elevated for at least 10 h, showing first order decay and a half-life of nearly 3 hours. Transfection of rhesus fibroblasts with R45 alone also led to the accumulation of nuclear pERK2 and addition of exogenous RSK augmented this effect. However, knock down of RSK during bona fide RRV infection had little to no effect on pERK2 accumulation or virion production. The cytoplasmic pools of pERK showed no co-localization with either RSK or R45 but activation of pERK downstream targets in this compartment was evident throughout infection. Together, these observations suggest a model in which R45 interacts with pERK2 to promote its nuclear accumulation, thereby promoting lytic viral gene expression while also preserving persistent and robust activation of both nuclear and cytoplasmic ERK targets.
Collapse
Affiliation(s)
- Evonne N. Woodson
- Myles H. Thaler Center for AIDS and Human Retrovirus Research, University of Virginia, Charlottesville, Virginia, United States of America
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, Charlottesville, Virginia, United States of America
| | - Melissa S. Anderson
- Myles H. Thaler Center for AIDS and Human Retrovirus Research, University of Virginia, Charlottesville, Virginia, United States of America
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, Charlottesville, Virginia, United States of America
| | - Matthew S. Loftus
- Myles H. Thaler Center for AIDS and Human Retrovirus Research, University of Virginia, Charlottesville, Virginia, United States of America
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, Charlottesville, Virginia, United States of America
| | - Dean H. Kedes
- Myles H. Thaler Center for AIDS and Human Retrovirus Research, University of Virginia, Charlottesville, Virginia, United States of America
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, Charlottesville, Virginia, United States of America
- Department of Internal Medicine, Division of Infectious Diseases and International Health, University of Virginia Health Systems, Charlottesville, Virginia, United States of America
| |
Collapse
|
206
|
Wu G, Qin XQ, Guo JJ, Li TY, Chen JH. AKT/ERK activation is associated with gastric cancer cell resistance to paclitaxel. Int J Clin Exp Pathol 2014; 7:1449-1458. [PMID: 24817940 PMCID: PMC4014224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 01/12/2014] [Accepted: 02/18/2014] [Indexed: 06/03/2023]
Abstract
Paclitaxel (PTX) has shown encouraging activity in the treatment of advanced gastric cancer (GC). However, the fact that more than half of GC patients respond poorly to PTX-based chemotherapies demonstrates the urgent need for biomarkers of PTX sensitivity in GC patients. In the present work, three GC cell lines (BGC-823, HGC-27 and NCI-N87) with different sensitivities to PTX were subjected to DNA microarray analysis. The significantly differentially expressed genes and microRNAs (miRs) were identified and pathway signatures for PTX sensitivity were proposed. Ingenuity Pathway Analysis results showed that the differentially expressed genes were mainly enriched in the ErbB signaling pathway and other pathways. Additionally, the AKT/ERK signaling pathway, which is the pathway downstream of ErbB, was predicted to be active in PTX-resistant GC cell lines. ErbB3 overexpression and AKT/ERK activation in PTX-resistant cell lines were validated, respectively, by quantitative PCR and immunoblotting. Furthermore, 10 miRs were dramatically differently expressed in the three GC cell lines, and a miR-gene network was constructed from these data. Our work uncovered a reliable signature for PTX sensitivity in GC and potential therapeutic targets for GC treatments.
Collapse
Affiliation(s)
- Gang Wu
- Department of General Surgery, Huashan Hospital, Fudan UniversityShanghai 200040, China
- Department of General Surgery, Renhe HospitalBaoshan District, Shanghai 20043, China
| | - Xue-Qian Qin
- Department of General Surgery, Renhe HospitalBaoshan District, Shanghai 20043, China
| | - Jing-Jing Guo
- Department of General Surgery, Renhe HospitalBaoshan District, Shanghai 20043, China
| | - Tian-Yi Li
- Department of General Surgery, Huashan Hospital, Fudan UniversityShanghai 200040, China
| | - Jin-Hong Chen
- Department of General Surgery, Huashan Hospital, Fudan UniversityShanghai 200040, China
| |
Collapse
|
207
|
Yang LX, Li BL, Liu XH, Yuan Y, Lu CJ, Chen R, Zhao J. RNA-seq reveals determinants of sensitivity to chemotherapy drugs in esophageal carcinoma cells. Int J Clin Exp Pathol 2014; 7:1524-1533. [PMID: 24817948 PMCID: PMC4014232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 01/12/2014] [Accepted: 01/27/2014] [Indexed: 06/03/2023]
Abstract
Chemotherapy remains the mainstay of treatment for patients with incurable disease of esophageal carcinoma. Most patients respond poorly to chemotherapy, it is necessary to figure out biomarkers for chemotherapy sensitivity or resistance to perform the individualized therapy. In present work, the sensitivities of two ESCC cell lines to 9 chemotherapy drugs were identified and the transcriptome of these two cell lines were investigated by RNA-seq, the correlation between the sensitivity to drugs and expression of some genes was attempted to construct. Eca-1 was more resistant to most of the chemotherapy drugs than Eca-109 cell line. RNA-seq results showed that there is dramatic difference in the basal expression between these two ESCC cell lines. Pathway analysis demonstrated that these differentially expressed genes were mainly enriched in Gαi signaling, calcium signaling, cAMP-mediated signaling, G-protein coupled receptor signaling and actin cytoskeleton signaling pathways. The molecules in Gαi signaling (ADCY1 and SSTR3) and actin cytoskeleton signaling (MYH6 and MYH7) were highly expressed in multidrug-resistant Eca-1 cells, which were validated by quantitative PCR. Activation of these two pathways results in the upregulation of downstream signaling, PKA signaling and Src-STAT3, and downregulation of RAF-ERK signaling, which was validated by immunoblotting experiments. Our work proposed that activation of Gαi signaling or actin cytoskeleton signaling may confer ESCC cells resistance to most chemotherapy drugs. Our work might provide potential biomarkers and therapeutic targets for treatment of EC patients.
Collapse
Affiliation(s)
- Li-Xin Yang
- Department of Cardiothoracic Surgery, Changhai Hospital, The Second Military Medical UniversityShanghai, China
| | - Bai-Ling Li
- Department of Cardiothoracic Surgery, Changhai Hospital, The Second Military Medical UniversityShanghai, China
| | - Xiao-Hong Liu
- Department of Cardiothoracic Surgery, Changhai Hospital, The Second Military Medical UniversityShanghai, China
| | - Yang Yuan
- Department of Cardiothoracic Surgery, Changhai Hospital, The Second Military Medical UniversityShanghai, China
| | - Chao-Jing Lu
- Department of Cardiothoracic Surgery, Changhai Hospital, The Second Military Medical UniversityShanghai, China
| | - Rui Chen
- International Joint Cancer Institute of The Second Military Medical UniversityShanghai, China
| | - Jian Zhao
- International Joint Cancer Institute of The Second Military Medical UniversityShanghai, China
| |
Collapse
|
208
|
Yue Y, Wang Y, He Y, Yang S, Chen Z, Wang Y, Xing S, Shen C, Amin HM, Wu D, Song YH. Reversal of bortezomib resistance in myelodysplastic syndrome cells by MAPK inhibitors. PLoS One 2014; 9:e90992. [PMID: 24608798 PMCID: PMC3946707 DOI: 10.1371/journal.pone.0090992] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2013] [Accepted: 02/05/2014] [Indexed: 01/20/2023] Open
Abstract
The myelodysplastic syndromes (MDS) comprise a heterogeneous group of malignant neoplasms with distinctive clinicopathological features. Currently, there is no specific approach for the treatment of MDS. Here, we report that bortezomib (BTZ), a proteasome inhibitor that has been used to treat plasma cell myeloma, induced G2/M phase cycle arrest in the MDS cell line SKM-1 through upregulation of Wee1, a negative regulator of G2/M phase transition. Treatment by BTZ led to reduced SKM-1 cell viability as well as increased apoptosis and autophagy. The BTZ-induced cell death was associated with reduced expression of p-ERK. To elucidate the implications of downregulation of p-ERK, we established the BTZ resistant cell line SKM-1R. Our data show that resistance to BTZ-induced apoptosis could be reversed by the MEK inhibitors U0126 or PD98059. Our results suggest that MAPK pathway may play an important role in mediating BTZ resistance.
Collapse
Affiliation(s)
- Yingxing Yue
- Cyrus Tang Hematology Center, Jiangsu Institute of Hematology, First Affiliated Hospital, Soochow University, Suzhou, China
| | - Ying Wang
- Jiangsu Institute of Hematology, The First Affiliated Hospital of Soochow University, Key Laboratory of Thrombosis and Hemostasis of Ministry of Health, Suzhou, China
| | - Yang He
- Jiangsu Institute of Hematology, The First Affiliated Hospital of Soochow University, Key Laboratory of Thrombosis and Hemostasis of Ministry of Health, Suzhou, China
| | - Shuting Yang
- Cyrus Tang Hematology Center, Jiangsu Institute of Hematology, First Affiliated Hospital, Soochow University, Suzhou, China
| | - Zixing Chen
- Jiangsu Institute of Hematology, The First Affiliated Hospital of Soochow University, Key Laboratory of Thrombosis and Hemostasis of Ministry of Health, Suzhou, China
| | - Yuanyuan Wang
- Jiangsu Institute of Hematology, The First Affiliated Hospital of Soochow University, Key Laboratory of Thrombosis and Hemostasis of Ministry of Health, Suzhou, China
| | - Shanshan Xing
- Cyrus Tang Hematology Center, Jiangsu Institute of Hematology, First Affiliated Hospital, Soochow University, Suzhou, China
| | - Congcong Shen
- Cyrus Tang Hematology Center, Jiangsu Institute of Hematology, First Affiliated Hospital, Soochow University, Suzhou, China
| | - Hesham M. Amin
- Department of Hematopathology, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
| | - Depei Wu
- Jiangsu Institute of Hematology, The First Affiliated Hospital of Soochow University, Key Laboratory of Thrombosis and Hemostasis of Ministry of Health, Suzhou, China
- * E-mail: (YHS); (DPW)
| | - Yao-Hua Song
- Cyrus Tang Hematology Center, Jiangsu Institute of Hematology, First Affiliated Hospital, Soochow University, Suzhou, China
- * E-mail: (YHS); (DPW)
| |
Collapse
|
209
|
Wills MKB, Tong J, Tremblay SL, Moran MF, Jones N. The ShcD signaling adaptor facilitates ligand-independent phosphorylation of the EGF receptor. Mol Biol Cell 2014; 25:739-52. [PMID: 24430869 PMCID: PMC3952845 DOI: 10.1091/mbc.e13-08-0434] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2013] [Revised: 12/06/2013] [Accepted: 01/08/2014] [Indexed: 11/12/2022] Open
Abstract
Proto-oncogenic Src homology and collagen (Shc) proteins have been considered archetypal adaptors of epidermal growth factor receptor (EGFR)-mediated signaling. We report that in addition to its role as an EGFR-binding partner and Grb2 platform, ShcD acts noncanonically to promote phosphorylation of select EGFR residues. Unexpectedly, Y1068, Y1148, and Y1173 are subject to ShcD-induced, cell-autonomous hyperphosphorylation in the absence of external stimuli. This response is not elicited by other Shc proteins and requires the intrinsic EGFR kinase, as well as the ShcD phosphotyrosine-binding (PTB) domain. Assessments of Erk, Akt, phospholipase C 1γ, and FAK pathways reveal no apparent distal signaling targets of ShcD. Nevertheless, the capacity of cultured cells to repopulate a wounded monolayer is markedly accelerated by ShcD in an EGFR kinase-dependent manner. Furthermore, detection of overexpressed ShcD coincident with EGFR phosphorylation in human gliomas suggests a clinical application for these findings. We thus demonstrate unique and relevant synergy between ShcD and EGFR that is unprecedented among signaling adaptors.
Collapse
Affiliation(s)
- Melanie K. B. Wills
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON N1G 2W1, Canada
| | - Jiefei Tong
- Program in Molecular Structure and Function, Hospital for Sick Children, Toronto, ON M5G 1X8, Canada
| | - Sylvie L. Tremblay
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON N1G 2W1, Canada
| | - Michael F. Moran
- Program in Molecular Structure and Function, Hospital for Sick Children, Toronto, ON M5G 1X8, Canada
- Department of Molecular Genetics and Banting and Best Department of Medical Research, University of Toronto, Toronto, ON M5G 1L6, Canada
| | - Nina Jones
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON N1G 2W1, Canada
| |
Collapse
|
210
|
Urbanelli L, Magini A, Ercolani L, Sagini K, Polchi A, Tancini B, Brozzi A, Armeni T, Principato G, Emiliani C. Oncogenic H-Ras up-regulates acid β-hexosaminidase by a mechanism dependent on the autophagy regulator TFEB. PLoS One 2014; 9:e89485. [PMID: 24586816 PMCID: PMC3933543 DOI: 10.1371/journal.pone.0089485] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2013] [Accepted: 01/21/2014] [Indexed: 11/19/2022] Open
Abstract
The expression of constitutively active H-RasV12 oncogene has been described to induce proliferative arrest and premature senescence in many cell models. There are a number of studies indicating an association between senescence and lysosomal enzyme alterations, e.g. lysosomal β-galactosidase is the most widely used biomarker to detect senescence in cultured cells and we previously reported that H-RasV12 up-regulates lysosomal glycohydrolases enzymatic activity in human fibroblasts. Here we investigated the molecular mechanisms underlying lysosomal glycohydrolase β-hexosaminidase up-regulation in human fibroblasts expressing the constitutively active H-RasV12. We demonstrated that H-Ras activation increases β-hexosaminidase expression and secretion by a Raf/extracellular signal-regulated protein kinase dependent pathway, through a mechanism that relies on the activity of the transcription factor EB (TFEB). Because of the pivotal role of TFEB in the regulation of lysosomal system biogenesis and function, our results suggest that this could be a general mechanism to enhance lysosomal enzymes activity during oncogene-induced senescence.
Collapse
Affiliation(s)
- Lorena Urbanelli
- Department of Experimental Medicine and Biochemical Sciences, University of Perugia, Perugia, Italy
- * E-mail: (CE); (LU)
| | - Alessandro Magini
- Department of Experimental Medicine and Biochemical Sciences, University of Perugia, Perugia, Italy
- Department of Medical and Biological Sciences (DSMB), University of Udine, Udine, Italy
| | - Luisa Ercolani
- Department of Clinical Sciences, Section of Biochemistry, Biology and Physics, Marche Polytechnic University, Ancona, Italy
| | - Krizia Sagini
- Department of Experimental Medicine and Biochemical Sciences, University of Perugia, Perugia, Italy
| | - Alice Polchi
- Department of Experimental Medicine and Biochemical Sciences, University of Perugia, Perugia, Italy
| | - Brunella Tancini
- Department of Experimental Medicine and Biochemical Sciences, University of Perugia, Perugia, Italy
| | - Alessandro Brozzi
- Department of Experimental Medicine and Biochemical Sciences, University of Perugia, Perugia, Italy
- Centro di Eccellenza sui Materiali Innovativi Nanostrutturati (CEMIN), University of Perugia, Perugia, Italy
| | - Tatiana Armeni
- Department of Clinical Sciences, Section of Biochemistry, Biology and Physics, Marche Polytechnic University, Ancona, Italy
| | - Giovanni Principato
- Department of Clinical Sciences, Section of Biochemistry, Biology and Physics, Marche Polytechnic University, Ancona, Italy
| | - Carla Emiliani
- Department of Experimental Medicine and Biochemical Sciences, University of Perugia, Perugia, Italy
- Centro di Eccellenza sui Materiali Innovativi Nanostrutturati (CEMIN), University of Perugia, Perugia, Italy
- * E-mail: (CE); (LU)
| |
Collapse
|
211
|
Wang Y, Liu D, Zhao H, Jiang H, Luo C, Wang M, Yin H. Cordyceps sinensis polysaccharide CPS-2 protects human mesangial cells from PDGF-BB-induced proliferation through the PDGF/ERK and TGF-β1/Smad pathways. Mol Cell Endocrinol 2014; 382:979-88. [PMID: 24309234 DOI: 10.1016/j.mce.2013.11.018] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/26/2013] [Revised: 10/29/2013] [Accepted: 11/25/2013] [Indexed: 12/18/2022]
Abstract
CPS-2, a Cordyceps sinensis polysaccharide, has been demonstrated to have significant therapeutic activity against chronic renal failure. However, little is known about the underlying molecular mechanism. In this study, we found that CPS-2 could inhibit PDGF-BB-induced human mesangial cells (HMCs) proliferation in a dose-dependent manner. In addition, CPS-2 notably suppressed the expression of α-SMA, PDGF receptor-beta (PDGFRβ), TGF-β1, and Smad 3 in PDGF-BB-treated HMCs. Furthermore, PDGF-BB-stimulated ERK activation was significantly inhibited by CPS-2, and this inhibitory effect was synergistically potentiated by U0126. CPS-2 could prevent the PDGFRβ promoter activity induced by PDGF-BB, and return expression of PDGFRβ, TGF-β1, and TGFβRI to normal levels while cells were under PDGFRβ and ERK silencing conditions and transfected with DN-ERK. Taken together, these findings demonstrated that CPS-2 reduces PDGF-BB-induced cell proliferation through the PDGF/ERK and TGF-β1/Smad pathways, and it may have bi-directional regulatory effects on the PDGF/ERK cellular signaling pathway.
Collapse
Affiliation(s)
- Ying Wang
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 210009, People's Republic of China; School of Life Science and Technology, China Pharmaceutical University, Nanjing 210009, Jiangsu, People's Republic of China
| | - Dan Liu
- School of Life Science and Technology, China Pharmaceutical University, Nanjing 210009, Jiangsu, People's Republic of China
| | - Huan Zhao
- School of Life Science and Technology, China Pharmaceutical University, Nanjing 210009, Jiangsu, People's Republic of China
| | - Huixing Jiang
- First Clinical Medical College, Nanjing University of Traditional Chinese Medicine, Nanjing Traditional Chinese Medicine Hospital, Nanjing 210010, Jiangsu, People's Republic of China
| | - Chen Luo
- School of Life Science and Technology, China Pharmaceutical University, Nanjing 210009, Jiangsu, People's Republic of China
| | - Min Wang
- School of Life Science and Technology, China Pharmaceutical University, Nanjing 210009, Jiangsu, People's Republic of China.
| | - Hongping Yin
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 210009, People's Republic of China; School of Life Science and Technology, China Pharmaceutical University, Nanjing 210009, Jiangsu, People's Republic of China.
| |
Collapse
|
212
|
Allard B, Bara I, Gilbert G, Carvalho G, Trian T, Ozier A, Gillibert-Duplantier J, Ousova O, Maurat E, Thumerel M, Quignard JF, Girodet PO, Marthan R, Berger P. Protease activated receptor-2 expression and function in asthmatic bronchial smooth muscle. PLoS One 2014; 9:e86945. [PMID: 24551046 PMCID: PMC3923726 DOI: 10.1371/journal.pone.0086945] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2013] [Accepted: 12/16/2013] [Indexed: 01/04/2023] Open
Abstract
Asthmatic bronchial smooth muscle (BSM) is characterized by structural remodeling associated with mast cell infiltration displaying features of chronic degranulation. Mast cell-derived tryptase can activate protease activated receptor type-2 (PAR-2) of BSM cells. The aims of the present study were (i) to evaluate the expression of PAR-2 in both asthmatic and non asthmatic BSM cells and, (ii) to analyze the effect of prolonged stimulation of PAR-2 in asthmatic BSM cells on cell signaling and proliferation. BSM cells were obtained from both 33 control subjects and 22 asthmatic patients. PAR-2 expression was assessed by flow cytometry, western blot and quantitative RT-PCR. Calcium response, transduction pathways and proliferation were evaluated before and following PAR-2 stimulation by SLIGKV-NH2 or trypsin for 1 to 3 days. Asthmatic BSM cells expressed higher basal levels of functional PAR-2 compared to controls in terms of mRNA, protein expression and calcium response. When PAR-2 expression was increased by means of lentivirus in control BSM cells to a level similar to that of asthmatic cells, PAR-2-induced calcium response was then similar in both types of cell. However, repeated PAR-2 stimulations increased the proliferation of asthmatic BSM cells but not that of control BSM cells even following lentiviral over-expression of PAR-2. Such an increased proliferation was related to an increased phosphorylation of ERK in asthmatic BSM cells. In conclusion, we have demonstrated that asthmatic BSM cells express increased baseline levels of functional PAR-2. This higher basal level of PAR-2 accounts for the increased calcium response to PAR-2 stimulation, whereas the increased proliferation to repeated PAR-2 stimulation is related to increased ERK phosphorylation.
Collapse
Affiliation(s)
- Benoit Allard
- Univ- Bordeaux, Centre de Recherche Cardio-Thoracique de Bordeaux, U1045, Département de Pharmacologie, Bordeaux, France
- INSERM, Centre de Recherche Cardio-Thoracique de Bordeaux, U1045, Bordeaux, France
| | - Imane Bara
- Univ- Bordeaux, Centre de Recherche Cardio-Thoracique de Bordeaux, U1045, Département de Pharmacologie, Bordeaux, France
- INSERM, Centre de Recherche Cardio-Thoracique de Bordeaux, U1045, Bordeaux, France
| | - Guillaume Gilbert
- Univ- Bordeaux, Centre de Recherche Cardio-Thoracique de Bordeaux, U1045, Département de Pharmacologie, Bordeaux, France
- INSERM, Centre de Recherche Cardio-Thoracique de Bordeaux, U1045, Bordeaux, France
| | - Gabrielle Carvalho
- Univ- Bordeaux, Centre de Recherche Cardio-Thoracique de Bordeaux, U1045, Département de Pharmacologie, Bordeaux, France
- INSERM, Centre de Recherche Cardio-Thoracique de Bordeaux, U1045, Bordeaux, France
| | - Thomas Trian
- Univ- Bordeaux, Centre de Recherche Cardio-Thoracique de Bordeaux, U1045, Département de Pharmacologie, Bordeaux, France
- INSERM, Centre de Recherche Cardio-Thoracique de Bordeaux, U1045, Bordeaux, France
| | - Annaig Ozier
- Univ- Bordeaux, Centre de Recherche Cardio-Thoracique de Bordeaux, U1045, Département de Pharmacologie, Bordeaux, France
- INSERM, Centre de Recherche Cardio-Thoracique de Bordeaux, U1045, Bordeaux, France
- CHU de Bordeaux, Service d'Exploration Fonctionnelle Respiratoire, Pessac, France
| | - Jennifer Gillibert-Duplantier
- Univ- Bordeaux, Centre de Recherche Cardio-Thoracique de Bordeaux, U1045, Département de Pharmacologie, Bordeaux, France
- INSERM, Centre de Recherche Cardio-Thoracique de Bordeaux, U1045, Bordeaux, France
| | - Olga Ousova
- Univ- Bordeaux, Centre de Recherche Cardio-Thoracique de Bordeaux, U1045, Département de Pharmacologie, Bordeaux, France
- INSERM, Centre de Recherche Cardio-Thoracique de Bordeaux, U1045, Bordeaux, France
| | - Elise Maurat
- Univ- Bordeaux, Centre de Recherche Cardio-Thoracique de Bordeaux, U1045, Département de Pharmacologie, Bordeaux, France
- INSERM, Centre de Recherche Cardio-Thoracique de Bordeaux, U1045, Bordeaux, France
| | - Matthieu Thumerel
- Univ- Bordeaux, Centre de Recherche Cardio-Thoracique de Bordeaux, U1045, Département de Pharmacologie, Bordeaux, France
- INSERM, Centre de Recherche Cardio-Thoracique de Bordeaux, U1045, Bordeaux, France
- CHU de Bordeaux, Service d'Exploration Fonctionnelle Respiratoire, Pessac, France
| | - Jean-François Quignard
- Univ- Bordeaux, Centre de Recherche Cardio-Thoracique de Bordeaux, U1045, Département de Pharmacologie, Bordeaux, France
- INSERM, Centre de Recherche Cardio-Thoracique de Bordeaux, U1045, Bordeaux, France
| | - Pierre-Olivier Girodet
- Univ- Bordeaux, Centre de Recherche Cardio-Thoracique de Bordeaux, U1045, Département de Pharmacologie, Bordeaux, France
- INSERM, Centre de Recherche Cardio-Thoracique de Bordeaux, U1045, Bordeaux, France
- CHU de Bordeaux, Service d'Exploration Fonctionnelle Respiratoire, Pessac, France
| | - Roger Marthan
- Univ- Bordeaux, Centre de Recherche Cardio-Thoracique de Bordeaux, U1045, Département de Pharmacologie, Bordeaux, France
- INSERM, Centre de Recherche Cardio-Thoracique de Bordeaux, U1045, Bordeaux, France
- CHU de Bordeaux, Service d'Exploration Fonctionnelle Respiratoire, Pessac, France
| | - Patrick Berger
- Univ- Bordeaux, Centre de Recherche Cardio-Thoracique de Bordeaux, U1045, Département de Pharmacologie, Bordeaux, France
- INSERM, Centre de Recherche Cardio-Thoracique de Bordeaux, U1045, Bordeaux, France
- CHU de Bordeaux, Service d'Exploration Fonctionnelle Respiratoire, Pessac, France
- * E-mail:
| |
Collapse
|
213
|
Zhang Y, Li R, Meng Y, Li S, Donelan W, Zhao Y, Qi L, Zhang M, Wang X, Cui T, Yang LJ, Tang D. Irisin stimulates browning of white adipocytes through mitogen-activated protein kinase p38 MAP kinase and ERK MAP kinase signaling. Diabetes 2014; 63:514-25. [PMID: 24150604 DOI: 10.2337/db13-1106] [Citation(s) in RCA: 505] [Impact Index Per Article: 50.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The number and activity of brown adipocytes are linked to the ability of mammals to resist body fat accumulation. In some conditions, certain white adipose tissue (WAT) depots are readily convertible to a ''brown-like'' state, which is associated with weight loss. Irisin, a newly identified hormone, is secreted by skeletal muscles into circulation and promotes WAT "browning" with unknown mechanisms. In the current study, we demonstrated in mice that recombinant irisin decreased the body weight and improved glucose homeostasis. We further showed that irisin upregulated uncoupling protein-1 (UCP-1; a regulator of thermogenic capability of brown fat) expression. This effect was possibly mediated by irisin-induced phosphorylation of the p38 mitogen-activated protein kinase (p38 MAPK) and extracellular signal-related kinase (ERK) signaling pathways. Inhibition of the p38 MAPK by SB203580 and ERK by U0126 abolished the upregulatory effect of irisin on UCP-1. In addition, irisin also promoted the expression of betatrophin, another newly identified hormone that promotes pancreatic β-cell proliferation and improves glucose tolerance. In summary, our data suggest that irisin can potentially prevent obesity and associated type 2 diabetes by stimulating expression of WAT browning-specific genes via the p38 MAPK and ERK pathways.
Collapse
Affiliation(s)
- Yuan Zhang
- Center for Stem Cell and Regenerative Medicine, The Second Hospital of Shandong University, Jinan, People's Republic of China
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
214
|
Abstract
Lung cancer is currently the most deadly malignancy in industrialized countries and accounts for 18% of all cancer-related deaths worldwide. Over 70% of patients with non-small cell lung cancer (NSCLC) are diagnosed at a late stage, with a 5-year survival below 10%. KRAS and the EGFR are frequently mutated in NSCLC and while targeted therapies for patients with EGFR mutations exist, oncogenic KRAS is thus far not druggable. KRAS activates multiple signalling pathways, including the PI3K/Akt pathway, the Raf-Mek-Erk pathway and the RalGDS/Ral pathway. Lung-specific expression of BrafV600E, the most prevalent BRAF mutation found in human tumors, results in Raf-Mek-Erk pathway activation and in the formation of benign adenomas that undergo widespread senescence in a Cre-activated Braf mouse model (Braf(CA)). However, oncogenic KRAS expression in mice induces adenocarcinomas, suggesting additional KRAS-activated pathways cooperate with sustained RAF-MEK-ERK signalling to bypass the oncogene-induced senescence proliferation arrest. To determine which KRAS effectors were responsible for tumor progression, we created four effector domain mutants (S35, G37, E38 and C40) in G12V-activated KRAS and expressed these alone or with BrafV600E in mouse lungs... The S35 and E38 mutants bind to Raf proteins but not PI3K or RalGDS; the G37 mutant binds to RalGDS and not Raf or PI3K and the C40 mutant is specific to PI3K. We designed lentiviral vectors to code for Cre recombinase along with KRAS mutants (V12, V12/S35, V12/G37, V12/E38 or V12/C40) or EGFP as a negative control.. These lentiviruses were used to infect Braf(CA) and wild-type mice. Surprisingly there was a significant decrease in tumor number and penetrance with each KRAS effector domain mutant relative to controls, suggesting that KRAS directly activates effectors with tumor suppressive functions.
Collapse
Affiliation(s)
- Guillaume Vandal
- Department of Biology, McGill University, Montréal, Quebec, Canada
| | - Benjamin Geiling
- Department of Biology, McGill University, Montréal, Quebec, Canada
| | - David Dankort
- Department of Biology, McGill University, Montréal, Quebec, Canada
- * E-mail:
| |
Collapse
|
215
|
Lin Z, Zhang C, Zhang M, Xu D, Fang Y, Zhou Z, Chen X, Qin N, Zhang X. Targeting cadherin-17 inactivates Ras/Raf/MEK/ERK signaling and inhibits cell proliferation in gastric cancer. PLoS One 2014; 9:e85296. [PMID: 24465527 PMCID: PMC3896370 DOI: 10.1371/journal.pone.0085296] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2013] [Accepted: 11/26/2013] [Indexed: 01/01/2023] Open
Abstract
Cadherin-17 (CDH17), one member of 7D-cadherin superfamily, was overexpressed in gastric cancer (GC) and was associated with poor survival, tumor recurrence, metastasis, and advanced tumor stage. So far the cellular function and signaling mechanism of CDH17 in GC remains unclear. In this study, we showed that over 66% of GC cell lines (20/30) were CDH17 positive. Tissue microarray (TMA) assay showed that 73.6% Chinese GC tissues (159/216) were CDH17 positive, while 37% respective adjacent normal tissues were CDH17 positive. Knockdown of CDH17 inhibited cell proliferation, migration, adhesion and colony formation, and also induced a cell cycle arrest and apoptosis in AGS human GC cells. On the other side, overexpression of CDH17 facilitated MGC-803 GC tumor growth in nude mice. Antibody array and Western blotting assay demonstrated that knockdown of CDH17 in AGS cells down-regulated integrin β series proteins, further inactivated the Ras/Raf/MEK/ERK pathway and led to p53 and p21 accumulation, which resulted in proliferation inhibition, cell-cycle arrest and apoptosis induction. Collectively, our data firstly demonstrate the capacity of CDH17 to regulate the activity of Ras/Raf/MEK/ERK pathway for cell proliferation in GC, and suggest that CDH17 can serve as an attractive therapeutic target for future research.
Collapse
Affiliation(s)
- Zhaohu Lin
- Department of Discovery Technology, Roche Pharma Research and Early Development China, Shanghai, China
| | - Chao Zhang
- Department of Discovery Technology, Roche Pharma Research and Early Development China, Shanghai, China
| | - Meifang Zhang
- Department of Discovery Technology, Roche Pharma Research and Early Development China, Shanghai, China
| | - Danqing Xu
- Department of Discovery Technology, Roche Pharma Research and Early Development China, Shanghai, China
| | - Yanfen Fang
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, East China Normal University, Shanghai, China
| | - Zheng Zhou
- Department of Discovery Technology, Roche Pharma Research and Early Development China, Shanghai, China
| | - Xiaolong Chen
- Department of Discovery Technology, Roche Pharma Research and Early Development China, Shanghai, China
| | - Ning Qin
- Department of Discovery Technology, Roche Pharma Research and Early Development China, Shanghai, China
| | - Xiongwen Zhang
- Department of Discovery Technology, Roche Pharma Research and Early Development China, Shanghai, China
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, East China Normal University, Shanghai, China
- * E-mail:
| |
Collapse
|
216
|
Li W, Zhao Q, Deng W, Chen T, Liu M, Xie J. Mycobacterium tuberculosis Rv3402c enhances mycobacterial survival within macrophages and modulates the host pro-inflammatory cytokines production via NF-kappa B/ERK/p38 signaling. PLoS One 2014. [PMID: 24722253 DOI: 10.1371/journal.pone.0094418pone-d-13-36639] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/07/2023] Open
Abstract
Intracellular survival plays a central role in the pathogenesis of Mycobacterium tuberculosis, a process which depends on an array of virulence factors to colonize and replicate within the host. The M. tuberculosis iron regulated open reading frame (ORF) rv3402c, encoding a conserved hypothetical protein, was shown to be up-regulated upon infection in both human and mice macrophages. To explore the function of this ORF, we heterologously expressed the rv3402c gene in the non-pathogenic fast-growing Mycobacterium smegmatis strain, and demonstrated that Rv3402c, a cell envelope-associated protein, was able to enhance the intracellular survival of recombinant M. smegmatis. Enhanced growth was not found to be the result of an increased resistance to intracellular stresses, as growth of the Rv3402c expressing strain was unaffected by iron depletion, H2O2 exposure, or acidic conditions. Colonization of macrophages by M. smegmatis expressing Rv3402c was associated with substantial cell death and significantly greater amount of TNF-α and IL-1β compared with controls. Rv3402c-induced TNF-α and IL-1β production was found to be mediated by NF-κB, ERK and p38 pathway in macrophages. In summary, our study suggests that Rv3402c delivered in a live M. smegmatis vehicle can modify the cytokines profile of macrophage, promote host cell death and enhance the persistence of mycobacterium within host cells.
Collapse
Affiliation(s)
- Wu Li
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Ministry of Education Eco-Environment of the Three Gorges Reservoir Region, School of Life Sciences, Southwest University, Chongqing, China
| | - Quanju Zhao
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Ministry of Education Eco-Environment of the Three Gorges Reservoir Region, School of Life Sciences, Southwest University, Chongqing, China
| | - Wanyan Deng
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Ministry of Education Eco-Environment of the Three Gorges Reservoir Region, School of Life Sciences, Southwest University, Chongqing, China
| | - Tian Chen
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Ministry of Education Eco-Environment of the Three Gorges Reservoir Region, School of Life Sciences, Southwest University, Chongqing, China
| | - Minqiang Liu
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Ministry of Education Eco-Environment of the Three Gorges Reservoir Region, School of Life Sciences, Southwest University, Chongqing, China
| | - Jianping Xie
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Ministry of Education Eco-Environment of the Three Gorges Reservoir Region, School of Life Sciences, Southwest University, Chongqing, China
| |
Collapse
|
217
|
Zhang F, Wang Z, Lu M, Yonekubo Y, Liang X, Zhang Y, Wu P, Zhou Y, Grinstein S, Hancock JF, Du G. Temporal production of the signaling lipid phosphatidic acid by phospholipase D2 determines the output of extracellular signal-regulated kinase signaling in cancer cells. Mol Cell Biol 2014; 34:84-95. [PMID: 24164897 PMCID: PMC3911278 DOI: 10.1128/mcb.00987-13] [Citation(s) in RCA: 81] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2013] [Revised: 08/22/2013] [Accepted: 10/21/2013] [Indexed: 01/14/2023] Open
Abstract
The Ras-extracellular signal-regulated kinase (ERK) cascade is an important signaling module in cells. One regulator of the Ras-ERK cascade is phosphatidic acid (PA) generated by phospholipase D (PLD) and diacylglycerol kinase (DGK). Using a newly developed PA biosensor, PASS (phosphatidic acid biosensor with superior sensitivity), we found that PA was generated sequentially by PLD and DGK in epidermal growth factor (EGF)-stimulated HCC1806 breast cancer cells. Inhibition of PLD2, one of the two PLD members, was sufficient to eliminate most of the PA production, whereas inhibition of DGK decreased PA production only at the later stages of EGF stimulation, suggesting that PLD2 precedes DGK activation. The temporal production of PA by PLD2 is important for the nuclear activation of ERK. While inhibition of both PLD and DGK had no effect on the overall ERK activity, inhibition of PLD2 but not PLD1 or DGK blocked the nuclear ERK activity in several cancer cell lines. The decrease of active ERK in the nucleus inhibited the activation of Elk1, c-fos, and Fra1, the ERK nuclear targets, leading to decreased proliferation of HCC1806 cells. Together, these findings reveal that PA production by PLD2 determines the output of ERK in cancer cell growth factor signaling.
Collapse
Affiliation(s)
- Feng Zhang
- Department of Integrative Biology and Pharmacology, University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - Ziqing Wang
- Department of Integrative Biology and Pharmacology, University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - Maryia Lu
- Department of Integrative Biology and Pharmacology, University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - Yoshiya Yonekubo
- Department of Integrative Biology and Pharmacology, University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - Xiao Liang
- Department of Integrative Biology and Pharmacology, University of Texas Health Science Center at Houston, Houston, Texas, USA
- Shanghai Institute of Digestive Disease, Shanghai Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yueqiang Zhang
- Department of Integrative Biology and Pharmacology, University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - Ping Wu
- Department of Integrative Biology and Pharmacology, University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - Yong Zhou
- Department of Integrative Biology and Pharmacology, University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - Sergio Grinstein
- Division of Cell Biology, Hospital for Sick Children, Toronto, Canada
| | - John F. Hancock
- Department of Integrative Biology and Pharmacology, University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - Guangwei Du
- Department of Integrative Biology and Pharmacology, University of Texas Health Science Center at Houston, Houston, Texas, USA
| |
Collapse
|
218
|
Abstract
Langerhans cell histiocytosis (LCH) has historically evolved in its classification from a primary immune dysregulatory disorder to what current evidence supports as a dendritic cell neoplasm with an immune-inflammatory component. A key part of the classification of LCH as a neoplasm has been the identification of BRAF V600E mutations in 35% to 60% of cases. Tumor protein p53 (TP53) and RAS mutations have also been identified, albeit in less than 2% of reported cases. Of note, over 50% of patients with another dendritic cell disease, Erdheim-Chester Disease, have also been shown to have BRAF V600E mutations. Although the BRAF mutations have not been shown to be associated with extent of disease, they may still provide a target for a molecularly guided approach to therapy. In cases of LCH in which no BRAF mutations were identified, there was evidence for activation of the RAS-RAF-MEK-extracellular signal-regulated kinases (ERK) pathway, suggesting that similar to other tumors, this pathway may be therapeutically exploitable. Anecdotal responses have been reported in a few patients with LCH and Erdheim-Chester Disease to vemurafenib, a BRAF V600E inhibitor. Although these results pave the way for careful, prospective clinical testing, selection of the optimal groups in which to test such inhibitors, alone or in combination, will be critical based on the toxicity profile thus far observed in adults with melanoma and other BRAF mutated tumors.
Collapse
Affiliation(s)
- Robert J Arceci
- From the Children's Center for Cancer and Blood Disorders, Hematology/Oncology, Ron Matricaria Institute of Molecular Medicine, Phoenix Children's Hospital, University of Arizona, College of Medicine, Phoenix, AZ
| |
Collapse
|
219
|
Fan DP, Zhang YM, Hu XC, Li JJ, Zhang W. Activation of AKT/ERK confers non-small cell lung cancer cells resistance to vinorelbine. Int J Clin Exp Pathol 2013; 7:134-143. [PMID: 24427333 PMCID: PMC3885467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Accepted: 12/10/2013] [Indexed: 06/03/2023]
Abstract
Vinorelbine is a semi-synthetic vinca-alkaloid approved for the treatment of non-small cell lung cancer (NSCLC). However, the lower objective response rate and higher adverse effects of vinorelbine hinder its wide use in treatment of advanced NSCLC. Therefore, it is of great interest to uncover the biomarkers for sensitivity of NSCLC cells to vinorelbine to allow the identification of patients most likely to benefit from vinorelbine-based chemotherapy and to improve the therapy. In present work, four NSCLC cell lines were divided into vinorelbine-sensitive (VS) group and vinorelbine-resistant (VR) group according to their sensitivities to vinorelbine. And then the gene expression profiles of these two groups was compared, the differentially expressed genes (expression difference higher than 100% and p<0.05, totally 496 genes) were applied to Ingenuity Pathway Analysis (IPA). IPA results showed that NF-κB and PTEN signaling were predicted to be inactivated in VR cell lines, which was partially validated by quantitative PCR or western blotting experiments. The higher expression of RAF1 mRNA and the activation of AKT/ERK proteins in VR NSCLC cell lines may confer resistance to vinorelbine. Our work may provide potential pathway signature for vinorelbine sensitivity and some therapeutic targets for combined therapy.
Collapse
Affiliation(s)
- Da-Ping Fan
- Department of Respiratory Medicine, First Clinical Medical College Affiliated to Harbin Medical University Harbin, China
| | - Yi-Mei Zhang
- Department of Respiratory Medicine, First Clinical Medical College Affiliated to Harbin Medical University Harbin, China
| | - Xiao-Chen Hu
- Department of Respiratory Medicine, First Clinical Medical College Affiliated to Harbin Medical University Harbin, China
| | - Jing-Jing Li
- Department of Respiratory Medicine, First Clinical Medical College Affiliated to Harbin Medical University Harbin, China
| | - Wei Zhang
- Department of Respiratory Medicine, First Clinical Medical College Affiliated to Harbin Medical University Harbin, China
| |
Collapse
|
220
|
Molnar C, de Celis JF. Tay bridge is a negative regulator of EGFR signalling and interacts with Erk and Mkp3 in the Drosophila melanogaster wing. PLoS Genet 2013; 9:e1003982. [PMID: 24348264 PMCID: PMC3861119 DOI: 10.1371/journal.pgen.1003982] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2013] [Accepted: 10/14/2013] [Indexed: 11/18/2022] Open
Abstract
The regulation of Extracellular regulated kinase (Erk) activity is a key aspect of signalling by pathways activated by extracellular ligands acting through tyrosine kinase transmembrane receptors. In this process, participate proteins with kinase activity that phosphorylate and activate Erk, as well as different phosphatases that inactivate Erk by de-phosphorylation. The state of Erk phosphorylation affects not only its activity, but also its subcellular localization, defining the repertoire of Erk target proteins, and consequently, the cellular response to Erk. In this work, we characterise Tay bridge as a novel component of the EGFR/Erk signalling pathway. Tay bridge is a large nuclear protein with a domain of homology with human AUTS2, and was previously identified due to the neuronal phenotypes displayed by loss-of-function mutations. We show that Tay bridge antagonizes EGFR signalling in the Drosophila melanogaster wing disc and other tissues, and that the protein interacts with both Erk and Mkp3. We suggest that Tay bridge constitutes a novel element involved in the regulation of Erk activity, acting as a nuclear docking for Erk that retains this protein in an inactive form in the nucleus. Extracellular regulated kinases (Erk) mediate signalling by pathways activated by tyrosine kinase transmembrane receptors. The level of activated Erk depends on a highly regulated balance between cytoplasmic kinases and nuclear/cytoplasmic phosphatases, which determine the state of Erk phosphorylation. This affects Erk activity and its subcellular localization, defining the repertoire of Erk targets, and consequently, the cellular response to Erk. In this work, we use a genetic approach to characterise the gene tay bridge as a novel component of the EGFR/Erk signalling pathway. Tay bridge has a domain of homology with human AUTS2, and was previously identified due to the neuronal phenotypes displayed by loss-of-function mutations. We show that Tay bridge antagonizes EGFR signalling in the Drosophila melanogaster wing disc and other tissues, and that the protein interacts with both Erk and Mkp3. We suggest that Tay bridge constitutes a novel element involved in the regulation of Erk activity, acting as a nuclear docking for Erk that retains this protein in an inactive form in the nucleus. These results could provide important insights into the clinical consequences of AUTS2 mutations in humans, which are related to behavioural perturbations including autism, mental retardation, Attention Deficit Hyperactivity Disorder and alcohol drinking behaviour.
Collapse
Affiliation(s)
- Cristina Molnar
- Centro de Biología Molecular “Severo Ochoa,” CSIC and Universidad Autónoma de Madrid, Madrid, Spain
| | - Jose F. de Celis
- Centro de Biología Molecular “Severo Ochoa,” CSIC and Universidad Autónoma de Madrid, Madrid, Spain
- * E-mail:
| |
Collapse
|
221
|
Guasti L, Cavlan D, Cogger K, Banu Z, Shakur A, Latif S, King PJ. Dlk1 up-regulates Gli1 expression in male rat adrenal capsule cells through the activation of β1 integrin and ERK1/2. Endocrinology 2013; 154:4675-84. [PMID: 24064361 DOI: 10.1210/en.2013-1211] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The development and maintenance of the zones of the adrenal cortex and their steroidal output are extremely important in the control of gluconeogenesis, the stress response, and blood volume. Sonic Hedgehog (Shh) is expressed in the adrenal cortex and signals to capsular cells, which can respond by migrating into the cortex and converting into a steroidogenic phenotype. Delta-like homologue 1 (Dlk1), a member of the Notch/Delta/Serrate family of epidermal growth factor-like repeat-containing proteins, has a well-established role in inhibiting adipocyte differentiation. We demonstrate that Shh and Dlk1 are coexpressed in the outer undifferentiated zone of the male rat adrenal and that Dlk1 signals to the adrenal capsule, activating glioma-associated oncogene homolog 1 transcription in a β1 integrin- and Erk1/2-dependent fashion. Moreover, Shh and Dlk1 expression inversely correlates with the size of the zona glomerulosa in rats after manipulation of the renin-angiotensin system, suggesting a role in the homeostatic maintenance of the gland.
Collapse
Affiliation(s)
- Leonardo Guasti
- Centre for Endocrinology, William Harvey Research Institute, Barts and the London, Queen Mary University of London, Charterhouse Square, London EC1M 6BQ, United Kingdom.
| | | | | | | | | | | | | |
Collapse
|
222
|
Rebollar A, López-García B. PAF104, a synthetic peptide to control rice blast disease by blocking appressorium formation in Magnaporthe oryzae. Mol Plant Microbe Interact 2013; 26:1407-1416. [PMID: 23902261 DOI: 10.1094/mpmi-04-13-0110-r] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Magnaporthe oryzae is the most devastating pathogen of rice and the main cause of crop losses worldwide. The successful management of blast disease caused by this fungus is a clear necessity. The synthetic peptide PAF104 has been characterized by its inhibition of M. oryzae appressorium formation on hydrophobic surfaces. Growth and the ability of conidia to germinate was not affected by PAF104, indicating the lack of toxicity on fungal conidia. The addition of the cutin monomer 1,16-hexadecanediol does not interfere with the inhibitory effect of PAF104 on in vitro hydrophobic surfaces. On the other hand, inhibition of appressorium formation by PAF104 was nullified by the exogenous addition of cAMP. Our results suggest that PAF104 affects the Pmk1 pathway by repression of the gene expression of MoMSB2, which encodes a sensing surface protein, and the mitogen-activated protein/extracellular signal-regulated kinase kinase kinase MST11. The pathogenicity of M. oryzae was reduced after PAF104 treatment specifically blocking appressorium formation. Our results support PAF104 as a promising compound to control rice blast disease by blocking a specific target related to appressorium formation, a process essential for infection of rice leaves. Moreover, PAF104 is proposed as a lead compound to develop novel specific fungicides with improved properties.
Collapse
|
223
|
Li X, Meng X, Kong J, Luo K, Luan S, Cao B, Liu N, Pang J, Shi X. Identification, cloning and characterization of an extracellular signal-regulated kinase (ERK) from Chinese shrimp, Fenneropenaeus chinensis. Fish Shellfish Immunol 2013; 35:1882-1890. [PMID: 24084041 DOI: 10.1016/j.fsi.2013.09.021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2013] [Revised: 09/12/2013] [Accepted: 09/16/2013] [Indexed: 06/02/2023]
Abstract
Extracellular signal-regulated kinase (ERK) is a serine/threonine-specific protein kinase, which participates in signaling transduction pathways that control intracellular events, including resumption of meiosis, embryogenesis, cell differentiation, cell proliferation, cell death and response to radiation. Some virus species evolved the ability to hijack the host cell ERK signaling transduction pathway for viral replications and gene expressions. To obtain a better understanding of ERK, we cloned a cDNA encoding ERK from the muscle of Fenneropenaeus chinensis (FcERK). The FcERK contained a 1098 bp open reading frame (ORF) encoding a protein of 365 amino acid residues with a conserved phosphorylation motif TEY in the kinase activation loop. Pair-wise and multiple sequence alignment revealed that ERK is highly conserved across taxa. The FcERK gene expressions in the hepatopancreas and gill were noticeably higher than the expression observed in the muscle. A challenge test was performed to reveal the responses of FcERK in different tissues to white spot syndrome virus (WSSV) infection. Post WSSV challenge, the FcERK expression in the gill significantly increased during the early stage of the viral infection, the FcERK expression in the muscle increased later than that in the gill, and the FcERK expression in the hepatopancreas significantly decreased. The FcERK gene expression profile accorded with the results that the virus primarily infects tissues originating from the ectoderm, with less infection of the tissues originating from the mesoderm, and hardly any infection in the tissues originating from the entoderm. Two single nucleotide polymorphisms (SNPs) were identified in the FcERK gene, involving C/T transition. The SNP genotypes of two groups of shrimps, respectively comprising 96 WSSV-resistant shrimps and 96 WSSV-susceptible shrimps were obtained using a high-resolution melting (HRM) method. In the two groups, the MAFs of both sites were greater than 0.05, and no site departed significantly (P < 0.05) from HWE. The genotype distributions of both mutation sites between the two groups were not significantly different. These results lead to a better understanding of the molecular mechanisms of the host-virus interaction and provide useful information for disease control.
Collapse
Affiliation(s)
- Xupeng Li
- College of Marine Life Science, Ocean University of China, Qingdao 266003, China; Key Laboratory for Sustainable Utilization of Marine Fisheries Resources, Ministry of Agriculture, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, 106 Nanjing Road, Qingdao 266071, China
| | | | | | | | | | | | | | | | | |
Collapse
|
224
|
Abstract
LH receptor (LHR) expression in the ovary is regulated by the RNA binding protein, (LHR mRNA binding protein [LRBP]), which has been identified as being mevalonate kinase. This study examined the role of microRNA miR-122 in LRBP-mediated LHR mRNA expression. Real-time PCR analysis of ovaries from pregnant mare serum gonadotropin/human chorionic gonadotropin (hCG)-primed female rats treated with hCG to down-regulate LHR expression showed that an increase in miR-122 expression preceded LHR mRNA down-regulation. The expression of miR-122 and its regulation was confirmed using fluorescent in situ hybridization of the frozen ovary sections using 5'-fluorescein isothiocyanate-labeled miR-122 locked nucleic acid probe. The increased expression of miR-122 preceded increased expression of LRBP mRNA and protein, and these increases were followed by LHR mRNA down-regulation. Inhibition of protein kinase A (PKA) and ERK1/2 signaling pathways by H89 and UO126, respectively, attenuated the hCG-mediated up-regulation of miR-122 levels. This was also confirmed in vitro using human granulosa cells. These results suggest the possibility that hCG-mediated miR-122 expression is mediated by the activation of cAMP/PKA/ERK signaling pathways. Inhibition of miR-122 by injection of the locked nucleic acid-conjugated antagomir of miR-122 abrogated the hCG-mediated increases in LRBP protein expression. Because it has been previously shown that miR-122 regulates sterol regulatory element-binding proteins (SREBPs) and SREBPs, in turn, regulate LRBP expression, the role of SREBPs in miR-122-mediated increase in LRBP expression was then examined. The levels of active forms of both SREBP-1a and SREBP-2 were increased in response to hCG treatment, and the stimulatory effect was sustained up to 4 hours. Taken together, our results suggest that hCG-induced down-regulation of LHR mRNA expression is mediated by activation of cAMP/PKA/ERK pathways to increase miR-122 expression, which then increases LRBP expression through the activation of SREBPs.
Collapse
Affiliation(s)
- Bindu Menon
- 6428 Medical Sciences Building I, 1301 Catherine Street, Ann Arbor, MI 48109-0617.
| | | | | | | | | |
Collapse
|
225
|
Abstract
Vascular endothelial growth factor receptor 2 (VEGFR-2), the primary receptor for VEGF, is crucial for normal endothelial function. sFlt-1, a truncated and soluble form of VEGFR-1 which binds and inhibits VEGF, is increased in preeclampsia and is positively regulated by low oxygen. Here, we investigated the effects of sFlt-1 and hypoxia on VEGFR-2 expression and signaling in the human placenta. VEGFR-2 transcript and protein levels were significantly decreased in preeclamptic placentae compared to controls (1.82 and 1.85 fold, respectively). An inverse correlation was observed for VEGFR-2 and sFlt-1 levels in both singleton and twin placentae from patients with preeclampsia. Immunofluorescence analyses revealed co-localization of VEGFR-2 and sFlt-1 in placental vasculature and co-immunoprecipitation analyses confirmed VEGFR-2 and sFlt-1 interaction only in preeclamptic placentae compared to age-matched controls. VEGFR-2 transcript and protein levels from explants cultured in 3% O2 were significantly decreased compared to those incubated at 20% O2 (5.9 and 12.47 fold, respectively). Also, VEGFR-2 transcript levels were significantly decreased in early first trimester placentae (low oxygen environment) compared to late first trimester placentae (2.05 fold). We next explored whether sFlt-1 directly affects VEGFR-2 expression. Treatment of first trimester placental explants with sFlt-1 resulted in significantly decreased levels of VEGFR-2 (2.03 fold) and downstream signaling proteins phospho-ERK (1.60 fold) and phospho-Akt (1.64 fold). Our findings show a novel hypoxia-induced and PE-related down-regulation of VEGFR-2 in the human placenta. sFlt-1, which is known to be increased in hypoxic conditions and PE, directly attenuates VEGFR-2 expression and signaling. A direct interaction between sFlt-1 and VEGFR-2 may represent an important mechanism in VEGFR-2 regulation, inhibition of VEGFR-2-mediated processes in placentation and a novel platform to examine the onset of preeclampsia.
Collapse
Affiliation(s)
- Ori Nevo
- Department of Obstetrics and Gynecology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario, Canada
- * E-mail:
| | - Dennis K. Lee
- Department of Obstetrics and Gynecology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario, Canada
| | - Isabella Caniggia
- Department of Obstetrics and Gynecology, Mount Sinai Hospital, Samuel Lunenfeld Research Institute, Toronto, Ontario, Canada
- Department of Physiology, University of Toronto, Toronto, Ontario, Canada
| |
Collapse
|
226
|
Vanderheyden WM, Gerstner JR, Tanenhaus A, Yin JC, Shaw PJ. ERK phosphorylation regulates sleep and plasticity in Drosophila. PLoS One 2013; 8:e81554. [PMID: 24244744 PMCID: PMC3828275 DOI: 10.1371/journal.pone.0081554] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2012] [Accepted: 10/21/2013] [Indexed: 11/20/2022] Open
Abstract
Given the relationship between sleep and plasticity, we examined the role of Extracellular signal-regulated kinase (ERK) in regulating baseline sleep, and modulating the response to waking experience. Both sleep deprivation and social enrichment increase ERK phosphorylation in wild-type flies. The effects of both sleep deprivation and social enrichment on structural plasticity in the LNvs can be recapitulated by expressing an active version of ERK (UAS-ERKSEM) pan-neuronally in the adult fly using GeneSwitch (Gsw) Gsw-elav-GAL4. Conversely, disrupting ERK reduces sleep and prevents both the behavioral and structural plasticity normally induced by social enrichment. Finally, using transgenic flies carrying a cAMP response Element (CRE)-luciferase reporter we show that activating ERK enhances CRE-Luc activity while disrupting ERK reduces it. These data suggest that ERK phosphorylation is an important mediator in transducing waking experience into sleep.
Collapse
Affiliation(s)
- William M. Vanderheyden
- Department of Anesthesiology, University of Michigan Medical School, Ann Arbor, Michigan, United States of America
- Department of Anatomy, Washington University Medical School, Saint Louis, Missouri, United States of America
- * E-mail:
| | - Jason R. Gerstner
- Translational Research Laboratories, Center for Sleep and Circadian Neurobiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Anne Tanenhaus
- Departments of Genetics and Neurology, University of Wisconsin, Madison, Madison, Wisconsin, United States of America
| | - Jerry C. Yin
- Departments of Genetics and Neurology, University of Wisconsin, Madison, Madison, Wisconsin, United States of America
| | - Paul J. Shaw
- Department of Anatomy, Washington University Medical School, Saint Louis, Missouri, United States of America
| |
Collapse
|
227
|
Cáceres A, Perdiguero B, Gómez CE, Cepeda MV, Caelles C, Sorzano CO, Esteban M. Involvement of the cellular phosphatase DUSP1 in vaccinia virus infection. PLoS Pathog 2013; 9:e1003719. [PMID: 24244156 PMCID: PMC3828168 DOI: 10.1371/journal.ppat.1003719] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2012] [Accepted: 09/05/2013] [Indexed: 12/30/2022] Open
Abstract
Poxviruses encode a large variety of proteins that mimic, block or enhance host cell signaling pathways on their own benefit. It has been reported that mitogen-activated protein kinases (MAPKs) are specifically upregulated during vaccinia virus (VACV) infection. Here, we have evaluated the role of the MAPK negative regulator dual specificity phosphatase 1 (DUSP1) in the infection of VACV. We demonstrated that DUSP1 expression is enhanced upon infection with the replicative WR virus and with the attenuated VACV viruses MVA and NYVAC. This upregulation is dependent on early viral gene expression. In the absence of DUSP1 in cultured cells, there is an increased activation of its molecular targets JNK and ERK and an enhanced WR replication. Moreover, DUSP1 knock-out (KO) mice are more susceptible to WR infection as a result of enhanced virus replication in the lungs. Significantly, MVA, which is known to produce non-permissive infections in most mammalian cell lines, is able to grow in DUSP1 KO immortalized murine embryo fibroblasts (MEFs). By confocal and electron microscopy assays, we showed that in the absence of DUSP1 MVA morphogenesis is similar as in permissive cell lines and demonstrated that DUSP1 is involved at the stage of transition between IVN and MV in VACV morphogenesis. In addition, we have observed that the secretion of pro-inflammatory cytokines at early times post-infection in KO mice infected with MVA and NYVAC is increased and that the adaptive immune response is enhanced in comparison with WT-infected mice. Altogether, these findings reveal that DUSP1 is involved in the replication and host range of VACV and in the regulation of host immune responses through the modulation of MAPKs. Thus, in this study we demonstrate that DUSP1 is actively involved in the antiviral host defense mechanism against a poxvirus infection. Phosphorylation is a post-translational modification that is highly conserved throughout the animal kingdom. Viruses have evolved to acquire their own kinases and phosphatases and to be able to modulate host phosphorylation mechanisms on their benefit. DUSP1 is an early induced gene that belongs to the superfamily of Dual-specificity phosphatases and provides an essential negative feedback regulation of MAPKs. DUSP1 is involved in innate and adaptive immune responses against different bacteria and parasites infections. The use of Knock-out technology has allowed us to understand the role of DUSP1 in the context of VACV infection both in cultured cells and in the in vivo mouse model. Here, we have showed that DUSP1 expression is upregulated during VACV infection and that DUSP1 plays an important role in VACV replication. Interestingly, we have demonstrated that the VACV attenuated virus MVA is able to grow in immortalized murine embryo fibroblasts in the absence of DUSP1. In vivo results showed that VACV replication-competent WR pathogenesis is enhanced in the absence of DUSP1. Furthermore, we have demonstrated that DUSP1 is involved in the host innate and adaptive responses against VACV. Altogether, we have presented a novel role for DUSP1 in VACV replication and anti-VACV host immune response.
Collapse
Affiliation(s)
- Ana Cáceres
- Department of Molecular and Cellular Biology, National Centre of Biotechnology, Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain
| | - Beatriz Perdiguero
- Department of Molecular and Cellular Biology, National Centre of Biotechnology, Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain
| | - Carmen E. Gómez
- Department of Molecular and Cellular Biology, National Centre of Biotechnology, Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain
| | - Maria Victoria Cepeda
- Department of Molecular and Cellular Biology, National Centre of Biotechnology, Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain
| | - Carme Caelles
- Department of Biochemistry and Molecular Biology, School of Pharmacy, University of Barcelona, Barcelona, Spain
| | - Carlos Oscar Sorzano
- Biocomputing Unit, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain
| | - Mariano Esteban
- Department of Molecular and Cellular Biology, National Centre of Biotechnology, Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain
- * E-mail:
| |
Collapse
|
228
|
Wang Z, Hou J, Lu L, Qi Z, Sun J, Gao W, Meng J, Wang Y, Sun H, Gu H, Xin Y, Guo X, Yang G. Small ribosomal protein subunit S7 suppresses ovarian tumorigenesis through regulation of the PI3K/AKT and MAPK pathways. PLoS One 2013; 8:e79117. [PMID: 24244431 PMCID: PMC3823983 DOI: 10.1371/journal.pone.0079117] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2013] [Accepted: 09/18/2013] [Indexed: 11/19/2022] Open
Abstract
Small ribosomal protein subunit S7 (RPS7) has been reported to be associated with various malignancies, but the role of RPS7 in ovarian cancer remains unclear. In this study, we found that silencing of RPS7 by a specific shRNA promoted ovarian cancer cell proliferation, accelerated cell cycle progression, and slightly reduced cell apoptosis and response to cisplatin treatment. Knockdown of RPS7 resulted in increased expression of P85α, P110α, and AKT2. Although the basal levels of ERK1/2, MEK1/2, and P38 were inconsistently altered in ovarian cancer cells, the phosphorylated forms of MEK1/2 (Ser217/221), ERK1/2 (Thr202/Tyr204), JNK1/2 (Thr183/Tyr185), and P38 (Thr180/Tyr182) were consistently reduced after RPS7 was silenced. Both the in vitro anchorage-independent colony formation and in vivo animal tumor formation capability of cells were enhanced after RPS7 was depleted. We also showed that silencing of RPS7 enhanced ovarian cancer cell migration and invasion. In sum, our results suggest that RPS7 suppresses ovarian tumorigenesis and metastasis through PI3K/AKT and MAPK signal pathways. Thus, RPS7 may be used as a potential marker for diagnosis and treatment of ovarian cancer.
Collapse
Affiliation(s)
- Ziliang Wang
- Cancer Institute, Fudan University Shanghai Cancer Center, Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Jing Hou
- Department of Radiation Oncology, Fudan University Shanghai Cancer Center, Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Lili Lu
- Life and Environment Science College, Shanghai Normal University, Shanghai, China
| | - Zihao Qi
- Cancer Institute, Fudan University Shanghai Cancer Center, Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Jianmin Sun
- Department of Gynecological Oncology, Fudan University Shanghai Cancer Center, Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Wen Gao
- Department of Gynecological Oncology, Fudan University Shanghai Cancer Center, Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Jiao Meng
- Cancer Institute, Fudan University Shanghai Cancer Center, Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Yan Wang
- Cancer Institute, Fudan University Shanghai Cancer Center, Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Huizhen Sun
- Cancer Institute, Fudan University Shanghai Cancer Center, Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Hongyu Gu
- Cancer Institute, Fudan University Shanghai Cancer Center, Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Yuhu Xin
- Cancer Institute, Fudan University Shanghai Cancer Center, Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Xiaomao Guo
- Department of Radiation Oncology, Fudan University Shanghai Cancer Center, Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
- * (XMG); (GY)
| | - Gong Yang
- Cancer Institute, Fudan University Shanghai Cancer Center, Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
- * (XMG); (GY)
| |
Collapse
|
229
|
Girard YK, Wang C, Ravi S, Howell MC, Mallela J, Alibrahim M, Green R, Hellermann G, Mohapatra SS, Mohapatra S. A 3D fibrous scaffold inducing tumoroids: a platform for anticancer drug development. PLoS One 2013; 8:e75345. [PMID: 24146752 PMCID: PMC3797770 DOI: 10.1371/journal.pone.0075345] [Citation(s) in RCA: 91] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2013] [Accepted: 08/12/2013] [Indexed: 01/18/2023] Open
Abstract
The development of a suitable three dimensional (3D) culture system for anticancer drug development remains an unmet need. Despite progress, a simple, rapid, scalable and inexpensive 3D-tumor model that recapitulates in vivo tumorigenesis is lacking. Herein, we report on the development and characterization of a 3D nanofibrous scaffold produced by electrospinning a mixture of poly(lactic-co-glycolic acid) (PLGA) and a block copolymer of polylactic acid (PLA) and mono-methoxypolyethylene glycol (mPEG) designated as 3P. Cancer cells cultured on the 3P scaffold formed tight irregular aggregates similar to in vivo tumors, referred to as tumoroids that depended on the topography and net charge of the scaffold. 3P scaffolds induced tumor cells to undergo the epithelial-to-mesenchymal transition (EMT) as demonstrated by up-regulation of vimentin and loss of E-cadherin expression. 3P tumoroids showed higher resistance to anticancer drugs than the same tumor cells grown as monolayers. Inhibition of ERK and PI3K signal pathways prevented EMT and reduced tumoroid formation, diameter and number. Fine needle aspirates, collected from tumor cells implanted in mice when cultured on 3P scaffolds formed tumoroids, but showed decreased sensitivity to anticancer drugs, compared to tumoroids formed by direct seeding. These results show that 3P scaffolds provide an excellent platform for producing tumoroids from tumor cell lines and from biopsies and that the platform can be used to culture patient biopsies, test for anticancer compounds and tailor a personalized cancer treatment.
Collapse
Affiliation(s)
- Yvonne K. Girard
- Department of Molecular Medicine, University of South Florida, Tampa, Florida, United States of America
- USF Nanomedicine Research Center, Morsani College of Medicine, University of South Florida, Tampa, Florida, United States of America
| | - Chunyan Wang
- Department of Molecular Medicine, University of South Florida, Tampa, Florida, United States of America
- USF Nanomedicine Research Center, Morsani College of Medicine, University of South Florida, Tampa, Florida, United States of America
| | - Sowndharya Ravi
- Department of Molecular Medicine, University of South Florida, Tampa, Florida, United States of America
- USF Nanomedicine Research Center, Morsani College of Medicine, University of South Florida, Tampa, Florida, United States of America
| | - Mark C. Howell
- Department of Molecular Medicine, University of South Florida, Tampa, Florida, United States of America
- USF Nanomedicine Research Center, Morsani College of Medicine, University of South Florida, Tampa, Florida, United States of America
| | - Jaya Mallela
- Department of Molecular Medicine, University of South Florida, Tampa, Florida, United States of America
- USF Nanomedicine Research Center, Morsani College of Medicine, University of South Florida, Tampa, Florida, United States of America
| | - Mahmoud Alibrahim
- Chemical and Biomedical Engineering Department, University of South Florida, Tampa, Florida, United States of America
| | - Ryan Green
- Department of Molecular Medicine, University of South Florida, Tampa, Florida, United States of America
- USF Nanomedicine Research Center, Morsani College of Medicine, University of South Florida, Tampa, Florida, United States of America
| | - Gary Hellermann
- USF Nanomedicine Research Center, Morsani College of Medicine, University of South Florida, Tampa, Florida, United States of America
| | - Shyam S. Mohapatra
- USF Nanomedicine Research Center, Morsani College of Medicine, University of South Florida, Tampa, Florida, United States of America
| | - Subhra Mohapatra
- Department of Molecular Medicine, University of South Florida, Tampa, Florida, United States of America
- USF Nanomedicine Research Center, Morsani College of Medicine, University of South Florida, Tampa, Florida, United States of America
- * E-mail:
| |
Collapse
|
230
|
Wang L, Jiang Q, Chu J, Lin L, Li XG, Chai GS, Wang Q, Wang JZ, Tian Q. Expression of Tau40 induces activation of cultured rat microglial cells. PLoS One 2013; 8:e76057. [PMID: 24146816 PMCID: PMC3795725 DOI: 10.1371/journal.pone.0076057] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2013] [Accepted: 08/20/2013] [Indexed: 12/13/2022] Open
Abstract
Accumulation of microtubule-associated protein tau has been observed in the brain of aging and tauopathies. Tau was observed in microglia, but its role is not illustrated. By immunofluorescence staining and the fractal dimension value assay in the present study, we observed that microglia were activated in the brains of rats and mice during aging, simultaneously, the immunoreactivities of total tau and the phosphorylated tau were significantly enhanced in the activated microglia. Furtherly by transient transfection of tau40 (human 2N/4R tau) into the cultured rat microglia, we demonstrated that expression of tau40 increased the level of Iba1, indicating activation of microglia. Moreover, expression of tau40 significantly enhanced the membranous localization of the phosphorylated tau at Ser396 in microglia possibly by a mechanism involving protein phosphatase 2A, extracellular signal-regulated kinase and glycogen synthase kinase-3β. It was also found that expression of tau40 promoted microglial migration and phagocytosis, but not proliferation. And we observed increased secretion of several cytokines, including interleukin (IL)-1β, IL-6, IL-10, tumor necrosis factor-α and nitric oxide after the expression of tau40. These data suggest a novel role of human 2N/4R tau in microglial activation.
Collapse
Affiliation(s)
- Lu Wang
- Department of Pathophysiology, Key Laboratory of Ministry of Education of Neurological Diseases, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Department of Physiology and Neurobiology, Xinxiang Medical University, Xinxiang, China
| | - Qian Jiang
- Department of Pathophysiology, Key Laboratory of Ministry of Education of Neurological Diseases, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jiang Chu
- Department of Pathophysiology, Key Laboratory of Ministry of Education of Neurological Diseases, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Li Lin
- Department of Pathophysiology, Key Laboratory of Ministry of Education of Neurological Diseases, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xiao-Guang Li
- Department of Pathophysiology, Key Laboratory of Ministry of Education of Neurological Diseases, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Gao-Shang Chai
- Department of Pathophysiology, Key Laboratory of Ministry of Education of Neurological Diseases, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Qun Wang
- Department of Pathophysiology, Key Laboratory of Ministry of Education of Neurological Diseases, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jian-Zhi Wang
- Department of Pathophysiology, Key Laboratory of Ministry of Education of Neurological Diseases, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- * E-mail: (JZW); (QT)
| | - Qing Tian
- Department of Pathophysiology, Key Laboratory of Ministry of Education of Neurological Diseases, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- * E-mail: (JZW); (QT)
| |
Collapse
|
231
|
Guo G, Yao W, Zhang Q, Bo Y. Oleanolic acid suppresses migration and invasion of malignant glioma cells by inactivating MAPK/ERK signaling pathway. PLoS One 2013; 8:e72079. [PMID: 23991044 PMCID: PMC3749117 DOI: 10.1371/journal.pone.0072079] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2013] [Accepted: 07/11/2013] [Indexed: 01/29/2023] Open
Abstract
Mitogen-activated protein kinases/Extracellular signal-regulated kinase (MAPK/ERK) pathway is essential for migration and invasion of malignant glioma. It is efficient to inhibit migration and invasion of glioma cells by targeting this pathway. Oleanolic acid (OA) has been well demonstrated to suppress survival, growth and angiogenesis of glioma cells. However, it is still unknown if OA affects the migration and invasion of glioma cells. We utilized U-87 MG glioma cell lines and primary glioma cells from patients to study the effect of OA on migration and invasion of glioma cells with multidisciplinary approaches. In this study, we found that OA significantly decreased the ability of glioma cells to migrate and invade. Epithelial-mesenchymal transition (EMT) of glioma cells was also suppressed by OA treatment. Furthermore, MAPK/ERK pathway was greatly inhibited in glioma cells under OA treatment. MAPK/ERK reactivation induced by a recombinant lentiviral vector, Lv-MEK, was able to rescue the inhibitory effect of OA on migration and invasion of glioma cells. Taken together, we provided evidences that OA was a MAPK/ERK pathway-targeting anti-tumor agent. Although the concentrations we used exceeded its physiological level, OA may be used to prevent migration and invasion of glioma cells by developing its derivatives with enhanced bioactivity.
Collapse
Affiliation(s)
- Guocai Guo
- Department of Neurosurgery, The Affiliated Hospital of Medical College, Qingdao University, Qingdao, China
| | - Weicheng Yao
- Department of Neurosurgery, The Affiliated Hospital of Medical College, Qingdao University, Qingdao, China
| | - Quanqin Zhang
- Department of Internal Medicine, The Affiliated Hospital of Medical College, Qingdao University, Qingdao, China
| | - Yongli Bo
- Department of Neurosurgery, The Affiliated Hospital of Medical College, Qingdao University, Qingdao, China
- * E-mail:
| |
Collapse
|
232
|
Chen PY, Yen JH, Kao RH, Chen JH. Down-regulation of the oncogene PTTG1 via the KLF6 tumor suppressor during induction of myeloid differentiation. PLoS One 2013; 8:e71282. [PMID: 23977008 PMCID: PMC3745464 DOI: 10.1371/journal.pone.0071282] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2013] [Accepted: 06/26/2013] [Indexed: 01/04/2023] Open
Abstract
The aberrant expression of proto-oncogenes is involved in processes that are responsible for cellular proliferation and the inhibition of myeloid differentiation in acute myeloid leukemia (AML). Pituitary Tumor-Transforming gene 1 (PTTG1), an oncogenic transcription factor, is abundantly expressed in various human cancers and hematopoietic malignancies. However, its expression in normal leukocytes and most normal tissues is very low or undetectable. The mechanism by which PTTG1 overexpression modifies myeloid cell development and promotes leukemogenesis remain unclear. To investigate the mechanistic links between PTTG1 overexpression and leukemia cell differentiation, we utilized phorbol 12-myristate 13-acetate (PMA), a well-known agent that triggers monocyte/macrophage differentiation, to analyze the expression patterns of PTTG1 in PMA-induced myeloid differentiation. We found that PTTG1 is down-regulated at the transcriptional level in PMA-treated HL-60 and THP1 cells. In addition, we identified a binding site for a tumor suppressor protein, Kruppel-like factor 6 (KLF6), in the PTTG1 promoter. We found that KLF6 could directly bind and repress PTTG1 expression. In HL-60 and THP1 cells, KLF6 mRNA and protein levels are up-regulated with a concordant reduction of PTTG1 expression upon treatment with PMA. Furthermore, KLF6 knockdown by shRNA abolished the suppression of PTTG1 and reduced the activation of the differentiation marker CD11b in PMA-primed cells. The protein kinase C (PKC) inhibitor and the MAPK/ERK kinase (MEK) inhibitor significantly blocked the potentiation of PMA-mediated KLF6 induction and the down-regulation of PTTG1, indicating that PTTG1 is suppressed via the activation of PKC/ERK/KLF6 pathway. Our findings suggest that drugs that increase the KLF6 inhibition of PTTG1 may have a therapeutic application in AML treatment strategies.
Collapse
Affiliation(s)
- Pei-Yi Chen
- Institute of Medical Science, Tzu Chi University, Hualien, Taiwan
- Center of Medical Genetics, Buddhist Tzu Chi General Hospital, Hualien, Taiwan
| | - Jui-Hung Yen
- Institute of Medical Science, Tzu Chi University, Hualien, Taiwan
- Department of Molecular Biology and Human Genetics, Tzu Chi University, Hualien, Taiwan
| | - Ruey-Ho Kao
- Department of Hematology-Oncology, Buddhist Tzu Chi General Hospital, Hualien, Taiwan
| | - Ji-Hshiung Chen
- Institute of Medical Science, Tzu Chi University, Hualien, Taiwan
- Department of Molecular Biology and Human Genetics, Tzu Chi University, Hualien, Taiwan
- * E-mail:
| |
Collapse
|
233
|
Potter WB, Basu T, O'Riordan KJ, Kirchner A, Rutecki P, Burger C, Roopra A. Reduced juvenile long-term depression in tuberous sclerosis complex is mitigated in adults by compensatory recruitment of mGluR5 and Erk signaling. PLoS Biol 2013; 11:e1001627. [PMID: 23966835 PMCID: PMC3742461 DOI: 10.1371/journal.pbio.1001627] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2012] [Accepted: 07/05/2013] [Indexed: 02/07/2023] Open
Abstract
A mouse model of the human genetic disorder tuberous sclerosis complex fails to undergo developmental down-regulation of mGluR5 expression and activation of Erk signaling, probably contributing to the aberrant plasticity and epilepsy in this disease. Tuberous sclerosis complex (TSC) is a multisystem genetic disease that manifests with mental retardation, tumor formation, autism, and epilepsy. Heightened signaling through the mammalian target of rapamycin (mTOR) pathway is involved in TSC pathology, however it remains unclear how other signaling pathways are perturbed and contribute to disease symptoms. Reduced long-term depression (LTD) was recently reported in TSC mutant mice. We find that although reduced LTD is a feature of the juvenile mutant hippocampus, heightened expression of metabotropic glutamate receptor 5 and constitutively activated Erk signaling in the adult hippocampus drives wild-type levels of LTD. Increased mGluR5 and Erk results in a novel mTOR-independent LTD in CA1 hippocampus of adult mice, and contributes to the development of epileptiform bursting activity in the TSC2+/− CA3 region of the hippocampus. Inhibition of mGluR5 or Erk signaling restores appropriate mTOR-dependence to LTD, and significantly reduces epileptiform bursting in TSC2+/− hippocampal slices. We also report that adult TSC2+/− mice exhibit a subtle perseverative behavioral phenotype that is eliminated by mGluR5 antagonism. These findings highlight the potential of modulating the mGluR5-Erk pathway in a developmental stage-specific manner to treat TSC. Tuberous sclerosis complex (TSC) is a genetic disorder that afflicts around 1 in 6,000 people and results from a mutation in one of two genes, TSC1 or TSC2. TSC patients suffer a number of neuronal symptoms including various degrees of autism, mental retardation, and epilepsy, the latter found in more than 80% of cases within the first year of life. In the TSC mutant mice that are used to model the disease, a region of the brain called the hippocampus fails to undergo long-term depression (LTD), a neuronal process that is important for learning and memory. We find that while this is the case in juvenile mutant mice, adult mice appear to have fixed this deficit. The “fix” involves the ramping up of signaling pathways involving mGluR5 and Erk. Although increased mGluR5 and Erk signaling outwardly fixes the problem of diminished LTD in adulthood, it renders the brain insensitive to the cues and inputs that normally work to control LTD. Moreover, the hippocampus in adult TSC mice is prone to seizures and impaired in learning and memory tasks. We find that drugs that target mGluR5 or Erk signaling repair the problems with excitability and learning deficits.
Collapse
Affiliation(s)
- Wyatt B. Potter
- Department of Neuroscience, Medical Science Center, University of Wisconsin–Madison, Madison, Wisconsin, United States of America
- Neuroscience Training Program, University of Wisconsin–Madison, Madison, Wisconsin, United States of America
| | - Trina Basu
- Department of Neuroscience, Medical Science Center, University of Wisconsin–Madison, Madison, Wisconsin, United States of America
- Neuroscience Training Program, University of Wisconsin–Madison, Madison, Wisconsin, United States of America
| | - Kenneth J. O'Riordan
- Department of Neurology, William S. Middleton Memorial VA Hospital and University of Wisconsin–Madison, Madison, Wisconsin, United States of America
| | - Allison Kirchner
- Department of Neuroscience, Medical Science Center, University of Wisconsin–Madison, Madison, Wisconsin, United States of America
| | - Paul Rutecki
- Department of Neurology, William S. Middleton Memorial VA Hospital and University of Wisconsin–Madison, Madison, Wisconsin, United States of America
| | - Corinna Burger
- Department of Neurology, William S. Middleton Memorial VA Hospital and University of Wisconsin–Madison, Madison, Wisconsin, United States of America
| | - Avtar Roopra
- Department of Neuroscience, Medical Science Center, University of Wisconsin–Madison, Madison, Wisconsin, United States of America
- * E-mail:
| |
Collapse
|
234
|
Zhang G, He LS, Wong YH, Qian PY. MKK3 was involved in larval settlement of the barnacle Amphibalanus amphitrite through activating the kinase activity of p38MAPK. PLoS One 2013; 8:e69510. [PMID: 23922727 PMCID: PMC3726695 DOI: 10.1371/journal.pone.0069510] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2013] [Accepted: 06/10/2013] [Indexed: 01/05/2023] Open
Abstract
The p38 mitogen-activated protein kinase (p38MAPK) plays a key role in larval settlement of the barnacle Amphibalanus amphitrite. To study the signaling pathway associated with p38MAPK during larval settlement, we sought to identify the upstream kinase of p38MAPK. Three MKKs (MKK3, MKK4 and MKK7) and three MAPKs (p38MAPK, ERK and JNK) in A. amphitrite were cloned and recombinantly expressed in E. coli. Through kinase assays, we found that MKK3, but not MKK4 or MKK7, phosphorylated p38MAPK. Furthermore, MKK3 activity was specific to p38MAPK, as it did not phosphorylate ERK or JNK. To further investigate the functional relationship between MKK3 and p38MAPK in vivo, we studied the localization of phospho-MKK3 (pMKK3) and MKK3 by immunostaining. Consistent with the patterns of p38MAPK and phospho-p38MAPK (pp38MAPK), pMKK3 and MKK3 mainly localized to the antennules of the cyprids. Western blot analysis revealed that pMKK3 levels, like pp38MAPK levels, were elevated at cyprid stage, compared to nauplii and juvenile stages. Moreover, pMKK3 levels increased after treatment with adult barnacle crude extracts, suggesting that MKK3 might mediate the stimulatory effects of adult barnacle extracts on the p38MAPK pathway.
Collapse
Affiliation(s)
- Gen Zhang
- KAUST Global Collaborative Research Program, Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China
| | - Li-Sheng He
- KAUST Global Collaborative Research Program, Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China
| | - Yue Him Wong
- KAUST Global Collaborative Research Program, Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China
| | - Pei-Yuan Qian
- KAUST Global Collaborative Research Program, Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China
| |
Collapse
|
235
|
Moore TC, Petro TM. IRF3 and ERK MAP-kinases control nitric oxide production from macrophages in response to poly-I:C. FEBS Lett 2013; 587:3014-20. [PMID: 23892079 DOI: 10.1016/j.febslet.2013.07.025] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2013] [Revised: 06/20/2013] [Accepted: 07/13/2013] [Indexed: 11/18/2022]
Abstract
Understanding nitric oxide (NO) in innate anti-viral immunity and immune-mediated pathology is hampered by incomplete details of its transcriptional and signaling factors. We found in macrophages that IRF3, ERK MAP-kinases, and PKR are essential to NO production in response to RNA-virus mimic, poly I:C, a TLR3 agonist. ERK's role in NO induction may be through phosphorylation of serine-171 of IRF3 and expression of NO-inducing cytokines, IL-6 and IFN-β. However, these cytokines induced less NO in IRF3 knockout or knockdown macrophages. These findings show that ERK and IRF3 coordinate induction of NO by macrophages in response to stimulation of TLR3.
Collapse
Affiliation(s)
- Tyler C Moore
- School of Biological Sciences, University of Nebraska-Lincoln, Lincoln, NE, USA
| | | |
Collapse
|
236
|
Scheinman EJ, Rostoker R, Leroith D. Cholesterol affects gene expression of the Jun family in colon carcinoma cells using different signaling pathways. Mol Cell Endocrinol 2013; 374:101-7. [PMID: 23643895 DOI: 10.1016/j.mce.2013.04.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2012] [Revised: 04/17/2013] [Accepted: 04/18/2013] [Indexed: 10/26/2022]
Abstract
Hyperlipidemia and hypercholesterolemia have been found to be important factors in cancer development and metastasis. However, the metabolic mechanism and downstream cellular processes following cholesterol stimulation are still unknown. Here we tested the effect of cholesterol on MC-38 colon cancer cells. Using Illumina gene array technology we found a number of genes that were differentially expressed following short term (20-40 min) and longer term (between 2 and 5h) cholesterol stimulation. Three genes were consistently increased at these time points; c-Jun, Jun-B and the chemokine CXCL-1. We have previously shown that cholesterol stimulation leads to PI3K/Akt phosphorylation, and now demonstrated that cholesterol inhibits ERK1/2 phosphorylation; both effects reversed when cholesterol is depleted from lipid rafts using methyl-β-cyclodextrin (MBCD). In addition, vanadate, an inhibitor of phosphatases, reversed the cholesterol inhibition of ERK1/2 phosphorylation. Specific inhibition of p-Akt by wortmannin did not affect cholesterol's stimulation of the expression of c-Jun and Jun-B, however the vanadate effect of increasing p-ERK1/2, inhibited c-Jun expression, specifically, and the MBCD effect of increasing p-ERK and inhibiting p-Akt reduced c-Jun expression. In contrast MBCD and vanadate both enhanced Jun-B gene expression in the presence of cholesterol and elevation of ERK phosphorylation. Thus there is apparently, a differential signaling pathway whereby cholesterol enhances gene expression of the Jun family members.
Collapse
Affiliation(s)
- Eyal J Scheinman
- Diabetes and Metabolism Clinical Research Center of Excellence, Clinical Research Institute at Rambam (CRIR) and the Faculty of Medicine, Technion, Haifa, Israel
| | | | | |
Collapse
|
237
|
Lu CY, Lai SC. Induction of matrix metalloproteinase-2 and -9 via Erk1/2-NF-κB pathway in human astroglia infected with Toxoplasma gondii. Acta Trop 2013; 127:14-20. [PMID: 23517828 DOI: 10.1016/j.actatropica.2013.03.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2012] [Revised: 02/18/2013] [Accepted: 03/03/2013] [Indexed: 01/31/2023]
Abstract
Matrix metalloproteinase (MMP)-2 and MMP-9 can cleave fibronectin, allowing leukocyte migration to the site of Toxoplasma gondii infection during toxoplasmic encephalitis. The aim of this study was to investigate the association between extracellular signal-regulated kinase (Erk)1/2-nuclear factor (NF)-κB pathway and MMP-2/-9 expression in astroglia infected with T. gondii tachyzoite in vitro. Our results showed that phosphorylated (p)-Erk1/2 transiently increased 1h post-infection (PI) and p-NF-κB significantly increased from 1h PI to 12h PI in cell homogenates. NF-κB was bound directly to oligonucleotides containing putative NF-κB binding sites for the MMP-9 promoter. Additionally, expression of p-NF-κB, MMP-2, and MMP-9 was significantly decreased by MG132, an indirect NF-κB inhibitor. Treatment with PD98059, an Erk kinase inhibitor, efficiently reduced p-Erk1/2, p-NF-κB, MMP-2, and MMP-9 expression. These results suggest that suppression of the Erk1/2-NF-κB signaling pathway causes reductions in MMP-2 and MMP-9 activities in astroglia response to T. gondii infection. Thus, inhibiting this signaling intermediate involved in MMP-2 and MMP-9 expression may be a potential method for controlling inflammatory development of T. gondii-induced encephalitis.
Collapse
Affiliation(s)
- Cheng-You Lu
- Institute of Medicine, Chung Shan Medical University, Taichung 402, Taiwan
| | | |
Collapse
|
238
|
Samal B, Ait-Ali D, Bunn S, Mustafa T, Eiden LE. Discrete signal transduction pathway utilization by a neuropeptide (PACAP) and a cytokine (TNF-alpha) first messenger in chromaffin cells, inferred from coupled transcriptome-promoter analysis of regulated gene cohorts. Peptides 2013; 45:48-60. [PMID: 23608709 PMCID: PMC3807697 DOI: 10.1016/j.peptides.2013.03.020] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2013] [Revised: 03/14/2013] [Accepted: 03/14/2013] [Indexed: 12/22/2022]
Abstract
Cultured bovine adrenal chromaffin cells (BCCs) are employed to study first messenger-specific signaling by cytokines and neurotransmitters occurring in the adrenal medulla following immune-related stress responses. Here, we show that the cytokine TNF-alpha, and the neuropeptide transmitter PACAP, acting through the TNFR2 and PAC1 receptors, activate distinct signaling pathways, with correspondingly distinct transcriptomic signatures in chromaffin cells. We have carried out a comprehensive integrated transcriptome analysis of TNF-alpha and PACAP gene regulation in BCCs using two microarray platforms to maximize transcript identification. Microarray data were validated using qRT-PCR. More than 90% of the transcripts up-regulated either by TNF-alpha or PACAP were specific to a single first messenger. The final list of transcripts induced by each first messenger was subjected to multiple algorithms to identify promoter/enhancer response elements for trans-acting factors whose activation could account for gene expression by either TNF-alpha or PACAP. Distinct groups of transcription factors potentially controlling the expression of TNF-alpha or PACAP-responsive genes were found: most of the genes up-regulated by TNF-alpha contained transcription factor binding sites for members of the Rel transcription factor family, suggesting TNF-alpha-TNFR2 signaling occurs mainly through the NF-KB signaling pathway. Surprisingly, EGR1 was predicted to be the primary transcription factor controlling PACAP-modulated genes, suggesting PACAP signaling to the nucleus occurs predominantly through ERK, rather than CREB activation. Comparison of TNFR2-dependent versus TNFR1-dependent gene induction, and EGR1-mediated transcriptional activation, may provide a pharmacological avenue to the unique pathways activated by the first messengers TNF-alpha and PACAP in neuronal and endocrine cells.
Collapse
MESH Headings
- Adrenal Glands/cytology
- Adrenal Glands/drug effects
- Adrenal Glands/immunology
- Animals
- Cattle
- Chromaffin Cells/cytology
- Chromaffin Cells/drug effects
- Chromaffin Cells/immunology
- Enhancer Elements, Genetic/drug effects
- Extracellular Signal-Regulated MAP Kinases/genetics
- Extracellular Signal-Regulated MAP Kinases/immunology
- Gene Expression Profiling
- Gene Expression Regulation
- NF-kappa B/genetics
- NF-kappa B/immunology
- Pituitary Adenylate Cyclase-Activating Polypeptide/pharmacology
- Primary Cell Culture
- Promoter Regions, Genetic/drug effects
- RNA, Messenger/genetics
- RNA, Messenger/immunology
- Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide, Type I/genetics
- Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide, Type I/immunology
- Receptors, Tumor Necrosis Factor, Type II/genetics
- Receptors, Tumor Necrosis Factor, Type II/immunology
- Signal Transduction
- Stress, Physiological
- Transcriptome/drug effects
- Transcriptome/immunology
- Tumor Necrosis Factor-alpha/pharmacology
Collapse
Affiliation(s)
- Babru Samal
- Section on Molecular Neuroscience, Laboratory of Cellular and
Molecular Regulation, National Institute of Mental Health, Bethesda, MD 20892,
USA
| | - Djida Ait-Ali
- Section on Molecular Neuroscience, Laboratory of Cellular and
Molecular Regulation, National Institute of Mental Health, Bethesda, MD 20892,
USA
| | - Stephen Bunn
- Centre for Neuroendocrinology, Department of Anatomy, School of
Medical Sciences, University of Otego, PO Box 913, Dunedin, New Zealand
| | - Tomris Mustafa
- Section on Molecular Neuroscience, Laboratory of Cellular and
Molecular Regulation, National Institute of Mental Health, Bethesda, MD 20892,
USA
| | - Lee E. Eiden
- Section on Molecular Neuroscience, Laboratory of Cellular and
Molecular Regulation, National Institute of Mental Health, Bethesda, MD 20892,
USA
- Corresponding author at: Section on Molecular
Neuroscience, Building 49, Room 5A-38,9000 Rockville Pike, Bethesda, MD 20892,
USA. Tel.: +1 301 496 4110; fax: +1 301 402 1748
| |
Collapse
|
239
|
Fang JF, Liang Y, Du JY, Fang JQ. Transcutaneous electrical nerve stimulation attenuates CFA-induced hyperalgesia and inhibits spinal ERK1/2-COX-2 pathway activation in rats. BMC Complement Altern Med 2013; 13:134. [PMID: 23768044 PMCID: PMC3689089 DOI: 10.1186/1472-6882-13-134] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/04/2013] [Accepted: 06/11/2013] [Indexed: 11/16/2022]
Abstract
BACKGROUND Transcutaneous electrical nerve stimulation (TENS) is a non-pharmacologic treatment for pain relief. In previous animal studies, TENS effectively alleviated Complete Freund's Adjuvant (CFA)- or carrageenan-induced inflammatory pain. Although TENS is known to produce analgesia via opioid activation in the brain and at the spinal level, few reports have investigated the signal transduction pathways mediated by TENS. Prior studies have verified the importance of the activation of extracellular signal-regulated kinase (ERK) signal transduction pathway in the spinal cord dorsal horn (SCDH) in acute and persistent inflammatory pains. Here, by using CFA rat model, we tested the efficacy of TENS on inhibiting the expressions of p-ERK1/2 and of its downstream cyclooxygenase-2 (COX-2) and the level of prostaglandin E2 (PGE2) at spinal level. METHODS Rats were randomly divided into control, model and TENS groups, and injected subcutaneously with 100 μl CFA or saline in the plantar surface of right hind paw. Rats in the TENS group were treated with TENS (constant aquare wave, 2 Hz and 100 Hz alternating frequencies, intensities ranging from 1 to 2 mA, lasting for 30 min each time) at 5 h and 24 h after injection. Paw withdrawal thresholds (PWTs) were measured with dynamic plantar aesthesiometer at 3d before modeling and 5 h, 6 h, and 25 h after CFA injection. The ipsilateral sides of the lumbar spinal cord dosral horns were harvested for detecting the expressions of p-ERK1/2 and COX-2 by western blot analysis and qPCR, and PGE2 by ELISA. RESULTS CFA-induced periphery inflammation decreased PWTs and increased paw volume of rats. TENS treatment significantly alleviated mechanical hyperalgesia caused by CFA. However, no anti-inflammatory effect of TENS was observed. Expression of p-ERK1/2 protein and COX-2 mRNA was significantly up-regualted at 5 h and 6 h after CFA injection, while COX-2 and PGE2 protein level only increased at 6 h after modeling. Furthermore, the high expression of p-ERK1/2 and COX-2, and over-production of PGE2 induced by CFA, were suppressed by TENS administration. CONCLUSIONS TENS may be an effective therapy in controlling inflammatory pain induced by CFA. Its analgesic effect may be associated with the inhibition of activation of the spinal ERK1/2-COX-2 pathway.
Collapse
Affiliation(s)
- Jun-Fan Fang
- Department of Neurobiology & Acupuncture Research, the Third Clinical College, Zhejiang Chinese Medical University, Hangzhou, China
| | - Yi Liang
- Department of Neurobiology & Acupuncture Research, the Third Clinical College, Zhejiang Chinese Medical University, Hangzhou, China
| | - Jun-Ying Du
- Department of Neurobiology & Acupuncture Research, the Third Clinical College, Zhejiang Chinese Medical University, Hangzhou, China
| | - Jian-Qiao Fang
- Department of Neurobiology & Acupuncture Research, the Third Clinical College, Zhejiang Chinese Medical University, Hangzhou, China
| |
Collapse
|
240
|
Patwardhan RS, Checker R, Sharma D, Sandur SK, Sainis KB. Involvement of ERK-Nrf-2 signaling in ionizing radiation induced cell death in normal and tumor cells. PLoS One 2013; 8:e65929. [PMID: 23776571 PMCID: PMC3679038 DOI: 10.1371/journal.pone.0065929] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2012] [Accepted: 05/01/2013] [Indexed: 12/30/2022] Open
Abstract
Prolonged oxidative stress favors tumorigenic environment and inflammation. Oxidative stress may trigger redox adaptation mechanism(s) in tumor cells but not normal cells. This may increase levels of intracellular antioxidants and establish a new redox homeostasis. Nrf-2, a master regulator of battery of antioxidant genes is constitutively activated in many tumor cells. Here we show that, murine T cell lymphoma EL-4 cells show constitutive and inducible radioresistance via activation of Nrf-2/ERK pathway. EL-4 cells contained lower levels of ROS than their normal counterpart murine splenic lymphocytes. In response to radiation, the thiol redox circuits, GSH and thioredoxin were modified in EL-4 cells. Pharmacological inhibitors of ERK and Nrf-2 significantly enhanced radiosensitivity and reduced clonogenic potential of EL-4 cells. Unirradiated lymphoma cells showed nuclear accumulation of Nrf-2, upregulation of its dependent genes and protein levels. Interestingly, MEK inhibitor abrogated its nuclear translocation suggesting role of ERK in basal and radiation induced Nrf-2 activation in tumor cells. Double knockdown of ERK and Nrf-2 resulted in higher sensitivity to radiation induced cell death as compared to individual knockdown cells. Importantly, NF-kB which is reported to be constitutively active in many tumors was not present at basal levels in EL-4 cells and its inhibition did not influence radiosensitivity of EL-4 cells. Thus our results reveal that, tumor cells which are subjected to heightened oxidative stress employ master regulator cellular redox homeostasis Nrf-2 for prevention of radiation induced cell death. Our study reveals the molecular basis of tumor radioresistance and highlights role of Nrf-2 and ERK.
Collapse
Affiliation(s)
- Raghavendra S. Patwardhan
- Radiation Biology & Health Sciences Division, Bio-Medical Group, Bhabha Atomic Research Centre, Trombay, Mumbai, India
| | - Rahul Checker
- Radiation Biology & Health Sciences Division, Bio-Medical Group, Bhabha Atomic Research Centre, Trombay, Mumbai, India
| | - Deepak Sharma
- Radiation Biology & Health Sciences Division, Bio-Medical Group, Bhabha Atomic Research Centre, Trombay, Mumbai, India
| | - Santosh K. Sandur
- Radiation Biology & Health Sciences Division, Bio-Medical Group, Bhabha Atomic Research Centre, Trombay, Mumbai, India
| | - Krishna B. Sainis
- Radiation Biology & Health Sciences Division, Bio-Medical Group, Bhabha Atomic Research Centre, Trombay, Mumbai, India
- * E-mail:
| |
Collapse
|
241
|
Marsh V, Davies EJ, Williams GT, Clarke AR. PTEN loss and KRAS activation cooperate in murine biliary tract malignancies. J Pathol 2013; 230:165-73. [PMID: 23483557 DOI: 10.1002/path.4189] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2012] [Revised: 02/20/2013] [Accepted: 02/27/2013] [Indexed: 12/15/2022]
Abstract
Carcinomas of the biliary tract are aggressive malignancies in humans. Loss of the tumour suppressor PTEN has previously been associated with cholangiocarcinoma development in a murine model. Activation of KRAS is reported in up to one-third of human cholangiocarcinomas and 50% of gall bladder carcinomas. In this study we aimed to test the potential interaction between PTEN and KRAS mutation in biliary tract malignancy. We used an inducible Cre-LoxP-based approach to coordinately delete PTEN and activate KRAS within the adult mouse biliary epithelium. We found that activation of KRAS alone has little effect upon biliary epithelium. Loss of PTEN alone results in the development of low-grade neoplastic lesions, following long latency and at low incidence. Combination of both mutations causes rapid development of biliary epithelial proliferative lesions, which progress through dysplasia to invasive carcinoma. We conclude that activation of the PI3'K pathway following loss of PTEN is sufficient to drive slow development of low-grade biliary lesions in mice. In contrast, mutational activation of KRAS does not result in a similar phenotype, despite a prediction that this should activate both the RAF-MEK-ERK and PI3'-kinase pathways. However, mutation of both genes results in rapid tumourigenesis, arguing that PTEN normally functions as a 'brake' on the PI3'-kinase pathway, limiting the influence of KRAS activation. Mutation of both genes creates a 'permissive' environment, allowing the full effects of both mutations to be manifested. These data reveal an in vivo synergy between these mutations and provides a new mouse model of biliary tract malignancy.
Collapse
Affiliation(s)
- Victoria Marsh
- Cardiff School of Biosciences, Cardiff University, Cardiff, UK
| | | | | | | |
Collapse
|
242
|
Cho HJ, Suh DS, Moon SH, Song YJ, Yoon MS, Park DY, Choi KU, Kim YK, Kim KH. Silibinin inhibits tumor growth through downregulation of extracellular signal-regulated kinase and Akt in vitro and in vivo in human ovarian cancer cells. J Agric Food Chem 2013; 61:4089-4096. [PMID: 23570653 DOI: 10.1021/jf400192v] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Anticancer activity of silibinin, a flavonoid, has been demonstrated in various cancer cell types. However, the underlying mechanisms were not elucidated in human ovarian cancer cells. The present study was undertaken to examine the effect of silibinin in vitro and in vivo on tumor growth in human ovarian cancer cells. Silibinin decreased cell viability in a dose- and time-dependent manner. Silibinin caused an increase in reactive oxygen species (ROS) generation, and the silibinin-induced cell death was prevented by the antioxidant N-acetylcysteine (NAC). Western blot analysis showed silibinin-induced downregulation of extracellular signal-regulated kinase (ERK) and Akt. Transfection of constitutively active forms of MEK and Akt prevented the silibinin-induced cell death. Oral administration of silibinin in animals with subcutaneous A2780 cells reduced tumor volume. Subsequent tumor tissue analysis showed that silibinin treatment induced a decrease in Ki-67-positive cells, an increase in transferase-mediated dUTP nick end labeling (TUNEL)-positive cells, activation of caspase-3, and inhibition of p-ERK and p-Akt. These results indicate that silibinin reduces tumor growth through inhibition of ERK and Akt in human ovarian cancer cells. These data suggest that silibinin may serve as a potential therapeutic agent for human ovarian cancers.
Collapse
Affiliation(s)
- Hyun Jin Cho
- Department of Medicine, Graduate School of Medicine, Pusan National University , Busan 602-739, Korea
| | | | | | | | | | | | | | | | | |
Collapse
|
243
|
Marcus Y, Shefer G, Sasson K, Kohen F, Limor R, Pappo O, Nevo N, Biton I, Bach M, Berkutzki T, Fridkin M, Benayahu D, Shechter Y, Stern N. Angiotensin 1-7 as means to prevent the metabolic syndrome: lessons from the fructose-fed rat model. Diabetes 2013; 62:1121-30. [PMID: 23250359 PMCID: PMC3609575 DOI: 10.2337/db12-0792] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
We studied the effects of chronic angiotensin 1-7 (Ang 1-7) treatment in an experimental model of the metabolic syndrome, i.e., rats given high-fructose/low-magnesium diet (HFrD). Rats were fed on HFrD for 24 weeks with and without Ang 1-7 (576 µg/kg/day, s.c., Alzet pumps). After 6 months, Ang 1-7-treated animals had lower body weight (-9.5%), total fat mass (detected by magnetic resonance imaging), and serum triglycerides (-51%), improved glucose tolerance, and better insulin sensitivity. Similar metabolic effects were also evident, albeit in the absence of weight loss, in rats first exposed to HFrD for 5 months and then subjected to short-term (4 weeks) treatment with Ang 1-7. Six months of Ang 1-7 treatment were associated with lower plasma renin activity (-40%) and serum aldosterone (-48%), less hepatosteatatitis, and a reduction in epididymal adipocyte volume. The marked attenuation of macrophage infiltration in white adipose tissue (WAT) was associated with reduced levels of the pP65 protein in the epididymal fat tissue, suggesting less activation of the nuclear factor-κB (NFκB) pathway in Ang 1-7-treated rats. WAT from Ang 1-7-treated rats showed reduced NADPH-stimulated superoxide production. In single muscle fibers (myofibers) harvested and grown ex vivo for 10 days, myofibers from HFrD rats gave rise to 20% less myogenic cells than the Ang 1-7-treated rats. Fully developed adipocytes were present in most HFrD myofiber cultures but entirely absent in cultures from Ang 1-7-treated rats. In summary, Ang 1-7 had an ameliorating effect on insulin resistance, hypertriglyceridemia, fatty liver, obesity, adipositis, and myogenic and adipogenic differentiation in muscle tissue in the HFrD rats.
Collapse
Affiliation(s)
- Yonit Marcus
- Department of Biological Chemistry, Weizmann Institute of Science, Rehovot, Israel
- Institute of Endocrinology, Metabolism, and Hypertension, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
| | - Gabi Shefer
- Institute of Endocrinology, Metabolism, and Hypertension, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Keren Sasson
- Department of Biological Chemistry, Weizmann Institute of Science, Rehovot, Israel
| | - Fortune Kohen
- Department of Biological Regulation, Weizmann Institute of Science, Rehovot, Israel
| | - Rona Limor
- Institute of Endocrinology, Metabolism, and Hypertension, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
| | - Orit Pappo
- Department of Pathology, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Nava Nevo
- Department of Biological Regulation, Weizmann Institute of Science, Rehovot, Israel
| | - Inbal Biton
- Department of Veterinary Resources, Weizmann Institute of Science, Rehovot, Israel
| | - Michal Bach
- Institute of Endocrinology, Metabolism, and Hypertension, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
| | - Tamara Berkutzki
- Department of Veterinary Resources, Weizmann Institute of Science, Rehovot, Israel
| | - Matityahu Fridkin
- Department of Organic Chemistry, Weizmann Institute of Science, Rehovot, Israel
| | - Dafna Benayahu
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Yoram Shechter
- Department of Biological Chemistry, Weizmann Institute of Science, Rehovot, Israel
| | - Naftali Stern
- Institute of Endocrinology, Metabolism, and Hypertension, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
- Corresponding author: Naftali Stern,
| |
Collapse
|
244
|
Suenaga M, Yamamoto M, Tabata S, Itakura S, Miyata M, Hamasaki S, Furukawa T. Influence of gefitinib and erlotinib on apoptosis and c-MYC expression in H23 lung cancer cells. Anticancer Res 2013; 33:1547-1554. [PMID: 23564796] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
BACKGROUND Gefitinib and erlotinib are inhibitors of epidermal growth factor receptor tyrosine kinase. The effects of these tyrosine kinase inhibitors on RAS-mutated cancer cells are unclear. MATERIALS AND METHODS Influence of gefitinib and erlotinib treatment was examined in H23 adenocarcinoma and A431 epidermoid carcinoma cells. The WST-1 assay was performed for evaluating cell growth. The phosphorylation status of extracellular-signal-regulated kinases (ERK) and AKT (protein kinase B) was examined by western blot. Flow cytometry was used for analyzing cell-cycle status and apoptosis detection. RESULTS In H23 cells, 20 μM erlotinib suppressed growth, while gefitinib did not suppress proliferation after 48 h of treatment. Neither gefitinib nor erlotinib affected the phosphorylation of ERK and AKT in H23 cells. Erlotinib augmented the sub-G1 population of H23 cells, while gefitinib reduced it. CONCLUSION In H23 cells, erlotinib accelerated apoptosis, while gefitinib induced G1 arrest.
Collapse
Affiliation(s)
- Mitsuhiro Suenaga
- Department of Cardiovascular, Respiratory and Metabolic Medicine, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan
| | | | | | | | | | | | | |
Collapse
|
245
|
Zhao R, Xie H, Lv S, Zheng Y, Yu M, Shen L, Sheng J. LeMAPK4 participated in cold-induced ethylene production in tomato fruit. J Sci Food Agric 2013; 93:1003-1009. [PMID: 23446913 DOI: 10.1002/jsfa.5790] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2012] [Revised: 05/29/2012] [Accepted: 06/02/2012] [Indexed: 06/01/2023]
Abstract
BACKGROUND Mitogen-activated protein kinase (MAPK, EC 2.7.11.24) cascade from several plant species has been shown to be activated during response to abiotic stress. Ethylene plays an important role in fruit tolerance to environmental stress. However, the mechanisms by which MAPK regulates defence systems in fruit and the relationship between MAPK and ethylene remain to be determined. RESULTS MAPK inhibitor significantly decreased the chilling tolerance of tomato (Lycopersicon esculentum cv. Lichun) fruit during cold storage. Moreover, decreases in ethylene content, LeACS2 expression and activities of 1-aminocyclopropane-1-carboxylic acid (ACC) synthase (ACS, EC 4.4.1.14) and ACC oxidase (ACO, EC 1.14.17.4) due to MAPK inhibitor occurred within 24 h after cold treatment. Upon treatment with cold and ethephon, the ethylene content, activities of ACS and ACO and expression of LeACS2, LeACO1 and LeMAPK4 increased. CONCLUSION The results showed the regulation of MAPK in ethylene biosynthesis to protect tomato fruit from cold stress. In addition, the participation of LeMAPK4 in cold-induced ethylene biosynthesis in tomato fruit was indicated.
Collapse
Affiliation(s)
- Ruirui Zhao
- College of Food Science and Nutritional Engineering, China Agricultural University, No. 17 Qinghua East Road, Beijing 100083, China
| | | | | | | | | | | | | |
Collapse
|
246
|
Ou J, Bharti K, Nodari A, Bertuzzi S, Arnheiter H. Vax1/2 genes counteract Mitf-induced respecification of the retinal pigment epithelium. PLoS One 2013; 8:e59247. [PMID: 23555005 PMCID: PMC3598659 DOI: 10.1371/journal.pone.0059247] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2012] [Accepted: 02/13/2013] [Indexed: 01/22/2023] Open
Abstract
During vertebrate eye development, the transcription factor MITF acts to promote the development of the retinal pigment epithelium (RPE). In embryos with Mitf mutations, the future RPE hyperproliferates and is respecified as retinal tissue but only in a small portion of the dorsal RPE. Using a series of genetic crosses, we show that this spatial restriction of RPE respecification is brought about by persistent expression of the anti-retinogenic ventral homeodomain gene Vax2 in the dorso-proximal and both Vax1 and Vax2 in the ventral RPE. We further show that dorso-proximal RPE respecification in Vax2/Mitf double mutants and dorso-proximal and ventral RPE respecification in Vax1/2/Mitf triple mutants result from increased FGF/MAP kinase signaling. In none of the mutants, however, does the distal RPE show signs of hyperproliferation or respecification, likely due to local JAGGED1/NOTCH signaling. Expression studies and optic vesicle culture experiments also suggest a role for NOTCH signaling within the mutant dorsal RPE domains, where ectopic JAGGED1 expression may partially counteract the effects of FGF/ERK1/2 signaling on RPE respecification. The results indicate the presence of complex interplays between distinct transcription factors and signaling molecules during eye development and show how RPE phenotypes associated with mutations in one gene are modulated by expression changes in other genes.
Collapse
Affiliation(s)
- Jingxing Ou
- Mammalian Development Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA.
| | | | | | | | | |
Collapse
|
247
|
Herath TDK, Darveau RP, Seneviratne CJ, Wang CY, Wang Y, Jin L. Tetra- and penta-acylated lipid A structures of Porphyromonas gingivalis LPS differentially activate TLR4-mediated NF-κB signal transduction cascade and immuno-inflammatory response in human gingival fibroblasts. PLoS One 2013; 8:e58496. [PMID: 23554896 PMCID: PMC3595299 DOI: 10.1371/journal.pone.0058496] [Citation(s) in RCA: 126] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2012] [Accepted: 02/05/2013] [Indexed: 12/21/2022] Open
Abstract
Background Porphyromonas gingivalis is a major pathogen of periodontal disease that affects a majority of adults worldwide. Increasing evidence shows that periodontal disease is linked to various systemic diseases like diabetes and cardiovascular disease, by contributing to increased systemic levels of inflammation. Lipopolysaccharides (LPS), as a key virulent attribute of P. gingivalis, possesses significant amount of lipid A heterogeneity containing tetra- (LPS1435/1449) and penta-acylated (LPS1690) structures. Hitherto, the exact molecular mechanism of P. gingivalis LPS involved in periodontal pathogenesis remains unclear, due to limited understanding of the specific receptors and signaling pathways involved in LPS-host cell interactions. Methodology/Principal Findings This study systematically investigated the effects of P. gingivalis LPS1435/1449 and LPS1690 on the expression of TLR2 and TLR4 signal transduction and the activation of pro-inflammatory cytokines IL-6 and IL-8 in human gingival fibroblasts (HGFs). We found that LPS1435/1449 and LPS1690 differentially modulated TLR2 and TLR4 expression. NF-κB pathway was significantly activated by LPS1690 but not by LPS1435/1449. In addition, LPS1690 induced significant expression of NF-κB and p38 MPAK pathways-related genes, such as NFKBIA, NFKB1, IKBKB, MAP2K4 and MAPK8. Notably, the pro-inflammatory genes including GM-CSF, CXCL10, G-CSF, IL-6, IL-8 and CCL2 were significantly upregulated by LPS1690 while down-regulated by LPS1435/1449. Blocking assays confirmed that TLR4-mediated NF-κB signaling was vital in LPS1690-induced expression of IL-6 and IL-8 in HGFs. Conclusions/Significance The present study suggests that the tetra- and penta-acylated lipid A structures of P. gingivalis LPS differentially activate TLR4-mediated NF-κB signaling pathway, and significantly modulate the expression of IL-6 and IL-8 in HGFs. The ability to alter the lipid A structure of LPS could be one of the strategies carried-out by P. gingivalis to evade innate host defense in gingival tissues, thereby contributing to periodontal pathogenesis.
Collapse
Affiliation(s)
- Thanuja D. K. Herath
- Faculty of Dentistry, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - Richard P. Darveau
- School of Dentistry, University of Washington, Seattle, Washington, United States of America
| | - Chaminda J. Seneviratne
- Faculty of Dentistry, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - Cun-Yu Wang
- School of Dentistry, University of California Los Angeles, Los Angeles, California, United States of America
| | - Yu Wang
- Department of Pharmacology & Pharmacy, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - Lijian Jin
- Faculty of Dentistry, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
- * E-mail:
| |
Collapse
|
248
|
Dong M, Hu N, Hua Y, Xu X, Kandadi MR, Guo R, Jiang S, Nair S, Hu D, Ren J. Chronic Akt activation attenuated lipopolysaccharide-induced cardiac dysfunction via Akt/GSK3β-dependent inhibition of apoptosis and ER stress. Biochim Biophys Acta Mol Basis Dis 2013; 1832:848-63. [PMID: 23474308 DOI: 10.1016/j.bbadis.2013.02.023] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2012] [Revised: 02/26/2013] [Accepted: 02/27/2013] [Indexed: 02/03/2023]
Abstract
Sepsis is characterized by systematic inflammation and contributes to cardiac dysfunction. This study was designed to examine the effect of protein kinase B (Akt) activation on lipopolysaccharide-induced cardiac anomalies and underlying mechanism(s) involved. Mechanical and intracellular Ca²⁺ properties were examined in myocardium from wild-type and transgenic mice with cardiac-specific chronic Akt overexpression following LPS (4 mg/kg, i.p.) challenge. Akt signaling cascade (Akt, phosphatase and tensin homologue deleted on chromosome ten, glycogen synthase kinase 3 beta), stress signal (extracellular-signal-regulated kinases, c-Jun N-terminal kinases, p38), apoptotic markers (Bcl-2 associated X protein, caspase-3/-9), endoplasmic reticulum (ER) stress markers (glucose-regulated protein 78, growth arrest and DNA damage induced gene-153, eukaryotic initiation factor 2α), inflammatory markers (tumor necrosis factor α, interleukin-1β, interleukin-6) and autophagic markers (Beclin-1, light chain 3B, autophagy-related gene 7 and sequestosome 1) were evaluated. Our results revealed that LPS induced marked decrease in ejection fraction, fractional shortening, cardiomyocyte contractile capacity with dampened intracellular Ca²⁺ release and clearance, elevated reactive oxygen species (ROS) generation and decreased glutathione and glutathione disulfide (GSH/GSSG) ratio, increased ERK, JNK, p38, GRP78, Gadd153, eIF2α, BAX, caspase-3 and -9, downregulated B cell lymphoma 2 (Bcl-2), the effects of which were significantly attenuated or obliterated by Akt activation. Akt activation itself did not affect cardiac contractile and intracellular Ca²⁺ properties, ROS production, oxidative stress, apoptosis and ER stress. In addition, LPS upregulated levels of Beclin-1, LC3B and Atg7, while suppressing p62 accumulation. Akt activation did not affect Beclin-1, LC3B, Atg7 and p62 in the presence or absence of LPS. Akt overexpression promoted phosphorylation of Akt and GSK3β. In vitro study using the GSK3β inhibitor SB216763 mimicked the response elicited by chronic Akt activation. Taken together, these data showed that Akt activation ameliorated LPS-induced cardiac contractile and intracellular Ca²⁺ anomalies through inhibition of apoptosis and ER stress, possibly involving an Akt/GSK3β-dependent mechanism.
Collapse
Affiliation(s)
- Maolong Dong
- Department of Burn and Cutaneous Surgery, Xijing Hospital, the Fourth Military Medical University, Xi'an 710032, PR China
| | | | | | | | | | | | | | | | | | | |
Collapse
|
249
|
Moon HS, Dincer F, Mantzoros CS. Amylin-induced downregulation of hippocampal neurogenesis is attenuated by leptin in a STAT3/AMPK/ERK-dependent manner in mice. Diabetologia 2013; 56:627-34. [PMID: 23224631 DOI: 10.1007/s00125-012-2799-3] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/19/2012] [Accepted: 11/19/2012] [Indexed: 10/27/2022]
Abstract
AIMS/HYPOTHESIS Both leptin and insulin sensitivity have been linked with pathophysiological processes involving the central nervous system in general, and the hippocampus in particular, but the role of leptin in hippocampal neurogenesis has not yet been elucidated. Also, no previous studies have evaluated whether amylin or the endogenous insulin sensitiser adiponectin interact with leptin to alter hippocampal neurogenesis in mouse hippocampal neuronal (HN) cells or investigated the role of leptin, amylin or adiponectin signalling in mouse HN cells. METHODS Hippocampal neurogenesis and leptin, amylin and adiponectin signalling were studied in vitro using mouse H19-7 HN cell lines. RESULTS Amylin decreased cell proliferation in a dose-dependent manner. This effect was diminished by leptin administration and was dependent on signal transducer and activator of transcription 3 (STAT3)/AMP-activated protein kinase (AMPK)/extracellular signal-regulated kinase (ERK). Adiponectin effects were null. We also observed, using immunocytochemical analysis, that amylin decreased activation of microtubule-associated protein 2, a specific neurite outgrowth marker, and synapsin, a specific synaptogenesis marker. By contrast, both effects were attenuated by co-administration of leptin. Finally, we observed that these effects were blocked by pre-treatment with AG490, a STAT3 inhibitor, and STAT3 small interfering RNA administration. CONCLUSIONS/INTERPRETATION Our data suggest that amylin in pharmacological concentrations may have a neurotoxic effect whereas leptin in physiological and pharmacological concentrations has a protective effect counteracting amylin-decreased hippocampal neurogenesis via STAT3/AMPK/ERK signalling in mouse H19-7 HN cell lines. Overall, our data support a novel role for leptin and amylin in the processes of mouse hippocampal neurogenesis and provide new insights into the mechanisms of neurogenic regulation.
Collapse
Affiliation(s)
- H-S Moon
- Division of Endocrinology, Diabetes, and Metabolism, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02130, USA
| | | | | |
Collapse
|
250
|
Soares HP, Ni Y, Kisfalvi K, Sinnett-Smith J, Rozengurt E. Different patterns of Akt and ERK feedback activation in response to rapamycin, active-site mTOR inhibitors and metformin in pancreatic cancer cells. PLoS One 2013; 8:e57289. [PMID: 23437362 PMCID: PMC3578870 DOI: 10.1371/journal.pone.0057289] [Citation(s) in RCA: 109] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2012] [Accepted: 01/20/2013] [Indexed: 11/18/2022] Open
Abstract
The mTOR pathway is aberrantly stimulated in many cancer cells, including pancreatic ductal adenocarcinoma (PDAC), and thus it is a potential target for therapy. However, the mTORC1/S6K axis also mediates negative feedback loops that attenuate signaling via insulin/IGF receptor and other tyrosine kinase receptors. Suppression of these feed-back loops unleashes over-activation of upstream pathways that potentially counterbalance the antiproliferative effects of mTOR inhibitors. Here, we demonstrate that treatment of PANC-1 or MiaPaCa-2 pancreatic cancer cells with either rapamycin or active-site mTOR inhibitors suppressed S6K and S6 phosphorylation induced by insulin and the GPCR agonist neurotensin. Rapamycin caused a striking increase in Akt phosphorylation at Ser(473) while the active-site inhibitors of mTOR (KU63794 and PP242) completely abrogated Akt phosphorylation at this site. Conversely, active-site inhibitors of mTOR cause a marked increase in ERK activation whereas rapamycin did not have any stimulatory effect on ERK activation. The results imply that first and second generation of mTOR inhibitors promote over-activation of different pro-oncogenic pathways in PDAC cells, suggesting that suppression of feed-back loops should be a major consideration in the use of these inhibitors for PDAC therapy. In contrast, metformin abolished mTORC1 activation without over-stimulating Akt phosphorylation on Ser(473) and prevented mitogen-stimulated ERK activation in PDAC cells. Metformin induced a more pronounced inhibition of proliferation than either KU63794 or rapamycin while, the active-site mTOR inhibitor was more effective than rapamycin. Thus, the effects of metformin on Akt and ERK activation are strikingly different from allosteric or active-site mTOR inhibitors in PDAC cells, though all these agents potently inhibited the mTORC1/S6K axis.
Collapse
MESH Headings
- Antibiotics, Antineoplastic/pharmacology
- Carcinoma, Pancreatic Ductal/drug therapy
- Carcinoma, Pancreatic Ductal/genetics
- Carcinoma, Pancreatic Ductal/metabolism
- Carcinoma, Pancreatic Ductal/pathology
- Cell Line, Tumor
- Cell Proliferation/drug effects
- Extracellular Signal-Regulated MAP Kinases/antagonists & inhibitors
- Extracellular Signal-Regulated MAP Kinases/genetics
- Extracellular Signal-Regulated MAP Kinases/metabolism
- Feedback, Physiological/drug effects
- Gene Expression Regulation, Neoplastic/drug effects
- Humans
- Hypoglycemic Agents/pharmacology
- Indoles/pharmacology
- Insulin/pharmacology
- Metformin/pharmacology
- Morpholines/pharmacology
- Neurotensin/pharmacology
- Pancreatic Neoplasms/drug therapy
- Pancreatic Neoplasms/genetics
- Pancreatic Neoplasms/metabolism
- Pancreatic Neoplasms/pathology
- Phosphorylation/drug effects
- Proto-Oncogene Proteins c-akt/antagonists & inhibitors
- Proto-Oncogene Proteins c-akt/genetics
- Proto-Oncogene Proteins c-akt/metabolism
- Purines/pharmacology
- Pyrimidines/pharmacology
- Ribosomal Protein S6 Kinases, 70-kDa/antagonists & inhibitors
- Ribosomal Protein S6 Kinases, 70-kDa/genetics
- Ribosomal Protein S6 Kinases, 70-kDa/metabolism
- Signal Transduction/drug effects
- Sirolimus/pharmacology
- TOR Serine-Threonine Kinases/antagonists & inhibitors
- TOR Serine-Threonine Kinases/genetics
- TOR Serine-Threonine Kinases/metabolism
Collapse
Affiliation(s)
- Heloisa P. Soares
- Division of Digestive Diseases, Department of Medicine; CURE: Digestive Diseases Research Center David Geffen School of Medicine and Molecular Biology Institute, University of California at Los Angeles, Los Angeles, California, United States of America
- Division of Hematology-Oncology, Department of Medicine, University of California at Los Angeles, Los Angeles, California, United States of America
| | - Yang Ni
- Division of Digestive Diseases, Department of Medicine; CURE: Digestive Diseases Research Center David Geffen School of Medicine and Molecular Biology Institute, University of California at Los Angeles, Los Angeles, California, United States of America
- Department of Thoracic Surgery, Provincial Hospital Affiliated to Shandong University, Jinan, Shandong, China
| | - Krisztina Kisfalvi
- Division of Digestive Diseases, Department of Medicine; CURE: Digestive Diseases Research Center David Geffen School of Medicine and Molecular Biology Institute, University of California at Los Angeles, Los Angeles, California, United States of America
| | - James Sinnett-Smith
- Division of Digestive Diseases, Department of Medicine; CURE: Digestive Diseases Research Center David Geffen School of Medicine and Molecular Biology Institute, University of California at Los Angeles, Los Angeles, California, United States of America
| | - Enrique Rozengurt
- Division of Digestive Diseases, Department of Medicine; CURE: Digestive Diseases Research Center David Geffen School of Medicine and Molecular Biology Institute, University of California at Los Angeles, Los Angeles, California, United States of America
| |
Collapse
|