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Kearney M, Franks L, Lee S, Tiersten A, Makower DF, Cigler T, Mundi P, Chi DC, Goel A, Klein P, Andreopoulou E, Sparano J, Trivedi M, Accordino M, Califano A, Hershman DL, Silva J, Kalinsky K. Phase I/II trial of ruxolitinib in combination with trastuzumab in metastatic HER2 positive breast cancer. Breast Cancer Res Treat 2021; 189:177-185. [PMID: 34169393 PMCID: PMC8487317 DOI: 10.1007/s10549-021-06306-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Accepted: 06/18/2021] [Indexed: 01/07/2023]
Abstract
Purpose: Preclinical data demonstrate STAT3 as an important regular in HER2+ tumors, and disruption of the IL6-JAK2-STAT-S100A8/S100A9 signaling cascade reduces HER2+ cell viability. Ruxolitinib is an FDA approved inhibitor of JAK1 and JAK2. We performed a phase I/II trial investigating the safety and efficacy of the combination of trastuzumab and ruxolitinib in patients with trastuzumab-resistant metastatic HER2+ breast cancer. Methods: Patients with metastatic HER2+ breast cancer progressing on at least 2 lines of HER2-directed therapy were eligible. The phase I portion determined the tolerable dose of ruxolitinib in combination with trastuzumab. The primary objective of the phase II was to assess the progression free survival (PFS) of the combination of ruxolitinib plus trastuzumab compared to historical control. Results: Twenty-eight patients were enrolled, with a median number of prior therapies of 4.5. Ruxolitinib 25mg twice daily was the recommended phase II dose with no DLTs. Of 26 evaluable patients in phase II, the median PFS was 8.3 weeks (95% CI: 7.1, 13.9). Among the 14 patients with measurable disease, 1 patient had a partial response and 4 patients had stable disease. Most of the adverse events were hematologic. Conclusion: While well-tolerated with a strong preclinical rationale, the combination of ruxolitinib and trastuzumab did not lead to an improvement in PFS compared to historical control in patients with trastuzumab-resistant metastatic HER2+ breast cancer.
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Affiliation(s)
- Matthew Kearney
- Columbia University Irving Medical Center, 630 W 168th St, New York, NY, 10032, USA
| | - Lauren Franks
- Mailman School of Public Health, Columbia University, 722 W 168th St, New York, NY, 10032, USA
| | - Shing Lee
- Mailman School of Public Health, Columbia University, 722 W 168th St, New York, NY, 10032, USA.,Herbert Irving Comprehensive Cancer Center, Columbia University, 1130 St Nicholas Ave, New York, NY, 10032, USA
| | - Amy Tiersten
- Icahn School of Medicine at Mount Sinai, 1 Gustave L. Levy Pl, New York, NY, 10029, USA
| | - Della F Makower
- Montefiore Medical Center, 111 E 210th St, Bronx, NY, 10467, USA
| | - Tessa Cigler
- Weill Cornell Medical, 1300 York Avenue, New York, NY, 10065, USA
| | - Prabhjot Mundi
- Columbia University Irving Medical Center, 630 W 168th St, New York, NY, 10032, USA.,Mailman School of Public Health, Columbia University, 722 W 168th St, New York, NY, 10032, USA
| | - Dow-Chung Chi
- Columbia University Irving Medical Center, 630 W 168th St, New York, NY, 10032, USA
| | - Anupama Goel
- Icahn School of Medicine at Mount Sinai, 1 Gustave L. Levy Pl, New York, NY, 10029, USA
| | - Pam Klein
- Herbert Irving Comprehensive Cancer Center, Columbia University, 1130 St Nicholas Ave, New York, NY, 10032, USA
| | | | - Joseph Sparano
- Montefiore Medical Center, 111 E 210th St, Bronx, NY, 10467, USA
| | - Meghna Trivedi
- Columbia University Irving Medical Center, 630 W 168th St, New York, NY, 10032, USA.,Herbert Irving Comprehensive Cancer Center, Columbia University, 1130 St Nicholas Ave, New York, NY, 10032, USA
| | - Melissa Accordino
- Columbia University Irving Medical Center, 630 W 168th St, New York, NY, 10032, USA.,Herbert Irving Comprehensive Cancer Center, Columbia University, 1130 St Nicholas Ave, New York, NY, 10032, USA
| | - Andrea Califano
- Herbert Irving Comprehensive Cancer Center, Columbia University, 1130 St Nicholas Ave, New York, NY, 10032, USA
| | - Dawn L Hershman
- Columbia University Irving Medical Center, 630 W 168th St, New York, NY, 10032, USA.,Mailman School of Public Health, Columbia University, 722 W 168th St, New York, NY, 10032, USA.,Herbert Irving Comprehensive Cancer Center, Columbia University, 1130 St Nicholas Ave, New York, NY, 10032, USA
| | - Jose Silva
- Herbert Irving Comprehensive Cancer Center, Columbia University, 1130 St Nicholas Ave, New York, NY, 10032, USA
| | - Kevin Kalinsky
- Winship Cancer Institute at Emory University, 1365 Clifton Road, Suite B4112, Atlanta, GA, 30322, USA.
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Abstract
BACKGROUND Signal transducers and activators of transcription 3 (STAT3) is a transcription factor that plays a key role in many cellular processes such as cell growth and cancer. However, the functions and mechanisms by which STAT3 regulates cellular processes are not fully understood. RESULTS Here we describe a novel function of STAT3. We demonstrated that STAT3 plays an important role in DNA replication. Specifically, knockdown of STAT3 reduced DNA replication while activation and ectopic expression of STAT3 promoted DNA replication. We further identified the WD repeat and HMG-box DNA-binding protein 1 (WDHD1), which plays an important role in DNA replication initiation, as a novel STAT3 target gene that mediated the DNA replication function of STAT3. We showed that STAT3 bind the promoter/up regulatory region of WDHD1 gene. CONCLUSIONS These studies identified a novel function of STAT3 that is mediated by its newly identified target gene WDHD1 and have important implications.
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Affiliation(s)
- Yunying Zhou
- Medical Research & Laboratory Diagnostic Center, Jinan Central Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China.,Medical Research & Laboratory Diagnostic Center, Central Hospital Affiliated To Shandong First Medical University, Jinan, China.,The Cancer Research Center, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China
| | - Jason J Chen
- Department of Microbiology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China. .,The Cancer Research Center, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China.
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Pan L, Chen X, Fu S, Yu W, Li C, Wang T, Lo HW, Lin J. LLY17, a novel small molecule STAT3 inhibitor induces apoptosis and suppresses cell migration and tumor growth in triple-negative breast cancer. Breast Cancer Res Treat 2020; 181:31-41. [PMID: 32240456 DOI: 10.1007/s10549-020-05613-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Accepted: 03/23/2020] [Indexed: 01/29/2023]
Abstract
PURPOSE Persistent STAT3 signaling is frequently detected in many cancer types including triple-negative breast cancer, and thus could potentially serve as a viable therapeutic target. We have designed a novel non-peptide compound LLY17 targeting STAT3 using Advanced Multiple Ligand Simultaneous Docking (AMLSD) methods. However, the efficacy of LLY17 has not been evaluated extensively in human and murine triple-negative breast cancer cells. In this study, we tested LLY17 in multiple human and murine triple-negative breast cancer cell lines. METHODS Human triple-negative breast cancer MDA-MB-468, MDA-MB-231, SUM159, and BT-549 cells, and murine triple-negative breast cancer 4T1 cells were used to study the inhibition effects of LLY17. The inhibition of STAT3 activation of LLY17 was investigated using western blot analysis. Cell viability, apoptosis and migration assays were carried out by MTT assay, Caspase-3/7 assay and wound healing assay, respectively. A mammary fat pad syngeneic mouse model was used to evaluate the antitumor effect of LLY17 in vivo. RESULTS LLY17 inhibited IL-6-mediated induction of STAT3 phosphorylation but had no effect on IFN-γ-induced STAT1 phosphorylation or EGF-induced ERK phosphorylation. LLY17 inhibited STAT3 phosphorylation and induced apoptosis in human and murine triple-negative breast cancer cells but exhibited minimal toxicity toward Luminal A subtype breast cancer MCF-7 cells. RNAi attenuation experiments supported the requirement of STAT3 for LLY17-mediated inhibition of cell viability in triple-negative breast cancer cells. In addition, LLY17 inhibited cell migration of human and murine triple-negative breast cancer cells. Furthermore, LLY17 suppressed tumor growth and STAT3 phosphorylation of triple-negative breast cancer cells in a mammary fat pad syngeneic mouse model in vivo. CONCLUSIONS Together, our findings suggest that targeting persistent STAT3 signaling by novel small molecule LLY17 may be a potential approach for the therapy of triple-negative breast cancer.
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Feng T, Cao W, Shen W, Zhang L, Gu X, Guo Y, Tsai HI, Liu X, Li J, Zhang J, Li S, Wu F, Liu Y. Arctigenin inhibits STAT3 and exhibits anticancer potential in human triple-negative breast cancer therapy. Oncotarget 2017; 8:329-44. [PMID: 27861147 DOI: 10.18632/oncotarget.13393] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Accepted: 11/11/2016] [Indexed: 12/31/2022] Open
Abstract
Triple-negative breast cancers (TNBCs) are the most aggressive and hard-to-treat breast tumors with poor prognosis, and exploration for novel therapeutic drugs is impending. Arctigenin (Atn), a bioactive lignan isolated from seeds of Arctium lappa L, has been reported to inhibit many cancer types; however, the effect of Atn on TNBC remains unclear. In this study, we demonstrated that Atn decreased proliferation, and induced apoptosis in TNBC cells. Furthermore, we explored the underlying mechanism of Atn inhibition on TNBC cells. Computational docking and affinity assay showed that Atn bound to the SH2 domain of STAT3. Atn inhibited STAT3 binding to genomic DNA by disrupting hydrogen bond linking between DNA and STAT3. In addition, Atn augmented Taxotere®-induced TNBC cell cytotoxicity. TNBC xenograft tests also confirmed the antitumor effect of Atn in vivo. These characteristics render Atn as a promising candidate drug for further development and for designing new effective STAT3 inhibitors.
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Lee HL, Park MH, Song JK, Jung YY, Kim Y, Kim KB, Hwang DY, Yoon do Y, Song MJ, Han SB, Hong JT. Tumor growth suppressive effect of IL-4 through p21-mediated activation of STAT6 in IL-4Rα overexpressed melanoma models. Oncotarget 2016; 7:23425-38. [PMID: 26993600 DOI: 10.18632/oncotarget.8111] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2015] [Accepted: 02/28/2016] [Indexed: 01/16/2023] Open
Abstract
To evaluate the significance of interleukin 4 (IL-4) in tumor development, we compared B16F10 melanoma growth in IL-4-overespressing transgenic mice (IL-4 mice) and non-transgenic mice. In IL-4 mice, reduced tumor volume and weight were observed when compared with those of non-transgenic mice. Significant activation of DNA binding activity of STAT6, phosphorylation of STAT6 as well as IL-4, IL-4Rα and p21 expression were found in the tumor tissues of IL-4 mice compared to non-transgenic mice. Higher expression of IL-4, STAT6 and p21 in human melanoma tissue compared to normal human skin tissue was also found. Higher expression of apoptotic protein such as cleaved caspase-3, cleaved caspase-8, cleaved caspase-9, Bax, p53 and p21, but lower expression levels of survival protein such as Bcl-2 were found in the tumor of IL-4 mice. In vitro study, we found that overexpression of IL-4 significantly inhibited SK-MEL-28 human melanoma cell and B16F10 murine melanoma cell growth via p21-mediated activation of STAT6 pathway as well as increased expression of apoptotic cell death proteins. Moreover, p21 knockdown with siRNA abolished IL-4 induced activation of STAT6 and expression of p53 and p21 accompanied with reduced IL-4 expression as well as melanoma cell growth inhibition. Therefore, these results showed that IL-4 overexpression suppressed tumor development through p21-mediated activation of STAT6 pathways in melanoma models.
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VanKlompenberg MK, Leyden E, Arnason AH, Zhang JT, Stefanski CD, Prosperi JR. APC loss in breast cancer leads to doxorubicin resistance via STAT3 activation. Oncotarget 2017; 8:102868-79. [PMID: 29262529 DOI: 10.18632/oncotarget.22263] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Accepted: 10/16/2017] [Indexed: 01/12/2023] Open
Abstract
Resistance to chemotherapy is one of the leading causes of death from breast cancer. We recently established that loss of Adenomatous Polyposis Coli (APC) in the Mouse Mammary Tumor Virus – Polyoma middle T (MMTV-PyMT) transgenic mouse model results in resistance to cisplatin or doxorubicin-induced apoptosis. Herein, we aim to establish the mechanism that is responsible for APC-mediated chemotherapeutic resistance. Our data demonstrate that MMTV-PyMT;ApcMin/+ cells have increased signal transducer and activator of transcription 3 (STAT3) activation. STAT3 can be constitutively activated in breast cancer, maintains the tumor initiating cell (TIC) population, and upregulates multidrug resistance protein 1 (MDR1). The activation of STAT3 in the MMTV-PyMT;ApcMin/+ model is independent of interleukin 6 (IL-6); however, enhanced EGFR expression in the MMTV-PyMT;ApcMin/+ cells may be responsible for the increased STAT3 activation. Inhibiting STAT3 with a small molecule inhibitor A69 in combination with doxorubicin, but not cisplatin, restores drug sensitivity. A69 also decreases doxorubicin enhanced MDR1 gene expression and the TIC population enhanced by loss of APC. In summary, these results have revealed the molecular mechanisms of APC loss in breast cancer that can guide future treatment plans to counteract chemotherapeutic resistance.
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Chen YD, Zhang Y, Dong TX, Xu YT, Zhang W, An TT, Liu PF, Yang XH. Hyperthermia with different temperatures inhibits proliferation and promotes apoptosis through the EGFR/STAT3 pathway in C6 rat glioma cells. Mol Med Rep 2017; 16:9401-9408. [PMID: 29039593 PMCID: PMC5779992 DOI: 10.3892/mmr.2017.7769] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2016] [Accepted: 08/31/2017] [Indexed: 02/07/2023] Open
Abstract
Malignant gliomas are a group of aggressive neoplasms among human cancers. The curative effects of current treatments are finite for improving the prognosis of patients. Hyperthermia (HT) is an effective treatment for cancers; however, the effects of HT with different temperatures in treatment of MG and relevant mechanisms remain unclear. MTT assay and Annexin V-fluorescein isothiocyanate/propidium iodide staining were used for investigating the proliferation and apoptosis of C6 cells, respectively. Western blotting was applied to detect the expression of proteins. Ultrasonography was employed to evaluate the tumor formation rate, growth rate, angiogenesis rate and degree of hardness of tumors in vivo. The authors certified that HT with 42–46°C × 1 h, 1 t could inhibit proliferation, promote apoptosis, reduce tumor formation rate, growth rate, angiogenesis rate, degree of hardness of tumors, ischemic tolerance and anoxic tolerance, and have synergy with temozolomide in C6 cells. Long-term HT (43°C × 1 h, 1 t/5 d, 90 d) did not cut down the sensitivity of C6 cells to HT, and sustainably inhibited the proliferation of C6 cells. Furthermore, the authors proved HT produced these effects primarily through inhibition of the EGFR/STAT3/HIF-1A/VEGF-A pathway.
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Affiliation(s)
- Yao-Dong Chen
- Department of Abdominal Ultrasonography, The First Clinical Hospital of Harbin Medical University, Harbin, Heilongjiang 150001, P.R. China
| | - Yu Zhang
- Department of Abdominal Ultrasonography, The First Clinical Hospital of Harbin Medical University, Harbin, Heilongjiang 150001, P.R. China
| | - Tian-Xiu Dong
- Department of Abdominal Ultrasonography, The First Clinical Hospital of Harbin Medical University, Harbin, Heilongjiang 150001, P.R. China
| | - Yu-Tong Xu
- Department of Abdominal Ultrasonography, The First Clinical Hospital of Harbin Medical University, Harbin, Heilongjiang 150001, P.R. China
| | - Wei Zhang
- Department of Abdominal Ultrasonography, The First Clinical Hospital of Harbin Medical University, Harbin, Heilongjiang 150001, P.R. China
| | - Ting-Ting An
- Department of Abdominal Ultrasonography, The First Clinical Hospital of Harbin Medical University, Harbin, Heilongjiang 150001, P.R. China
| | - Peng-Fei Liu
- Department of Magnetic Resonance, The First Clinical Hospital of Harbin Medical University, Harbin, Heilongjiang 150001, P.R. China
| | - Xiu-Hua Yang
- Department of Abdominal Ultrasonography, The First Clinical Hospital of Harbin Medical University, Harbin, Heilongjiang 150001, P.R. China
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Speth Z, Islam T, Banerjee K, Resat H. EGFR signaling pathways are wired differently in normal 184A1L5 human mammary epithelial and MDA-MB-231 breast cancer cells. J Cell Commun Signal 2017; 11:341-56. [PMID: 28357710 DOI: 10.1007/s12079-017-0389-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Accepted: 03/22/2017] [Indexed: 01/10/2023] Open
Abstract
Because of differences in the downstream signaling patterns of its pathways, the role of the human epidermal growth factor family of receptors (HER) in promoting cell growth and survival is cell line and context dependent. Using two model cell lines, we have studied how the regulatory interaction network among the key proteins of HER signaling pathways may be rewired upon normal to cancerous transformation. We in particular investigated how the transcription factor STAT3 and several key kinases' involvement in cancer-related signaling processes differ between normal 184A1L5 human mammary epithelial (HME) and MDA-MB-231 breast cancer epithelial cells. Comparison of the responses in these cells showed that normal-to-cancerous cellular transformation causes a major re-wiring of the growth factor initiated signaling. In particular, we found that: i) regulatory interactions between Erk, p38, JNK and STAT3 are triangulated and tightly coupled in 184A1L5 HME cells, and ii) STAT3 is only weakly associated with the Erk-p38-JNK pathway in MDA-MB-231 cells. Utilizing the concept of pathway substitution, we predicted how the observed differences in the regulatory interactions may affect the proliferation/survival and motility responses of the 184A1L5 and MDA-MB-231 cells when exposed to various inhibitors. We then validated our predictions experimentally to complete the experiment-computation-experiment iteration loop. Validated differences in the regulatory interactions of the 184A1L5 and MDA-MB-231 cells indicated that instead of inhibiting STAT3, which has severe toxic side effects, simultaneous inhibition of JNK together with Erk or p38 could be a more effective strategy to impose cell death selectively to MDA-MB-231 cancer cells while considerably lowering the side effects to normal epithelial cells. Presented analysis establishes a framework with examples that would enable cell signaling researchers to identify the signaling network structures which can be used to predict the phenotypic responses in particular cell lines of interest.
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Choi YK, Kim J, Lee KM, Choi YJ, Ye BR, Kim MS, Ko SG, Lee SH, Kang DH, Heo SJ. Tuberatolide B Suppresses Cancer Progression by Promoting ROS-Mediated Inhibition of STAT3 Signaling. Mar Drugs 2017; 15:E55. [PMID: 28245605 DOI: 10.3390/md15030055] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2016] [Revised: 02/06/2017] [Accepted: 02/17/2017] [Indexed: 02/06/2023] Open
Abstract
Tuberatolide B (TTB, C27H34O4) is a diastereomeric meroterpenoid isolated from the Korean marine algae Sargassum macrocarpum. However, the anticancer effects of TTB remain unknown. In this study, we demonstrate that TTB inhibits tumor growth in breast, lung, colon, prostate, and cervical cancer cells. To examine the mechanism by which TTB suppresses cell growth, we determined the effect of TTB on apoptosis, ROS generation, DNA damage, and signal transduction. TTB induced ROS production in MDA-MB-231, A549, and HCT116 cells. Moreover, TTB enhanced DNA damage by inducing γH2AX foci formation and the phosphorylation of DNA damage-related proteins such as Chk2 and H2AX. Furthermore, TTB selectively inhibited STAT3 activation, which resulted in a reduction in cyclin D1, MMP-9, survivin, VEGF, and IL-6. In addition, TTB-induced ROS generation caused STAT3 inhibition, DNA damage, and apoptotic cell death. Therefore, TTB suppresses cancer progression by promoting ROS-mediated inhibition of STAT3 signaling, suggesting that TTB is useful for the treatment of cancer.
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Jiang R, Wang X, Jin Z, Li K. Association of Nuclear PIM1 Expression with Lymph Node Metastasis and Poor Prognosis in Patients with Lung Adenocarcinoma and Squamous Cell Carcinoma. J Cancer 2016; 7:324-34. [PMID: 26918046 PMCID: PMC4747887 DOI: 10.7150/jca.13422] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2015] [Accepted: 10/17/2015] [Indexed: 12/20/2022] Open
Abstract
Increasing evidence indicates that aberrant expression of PIM1, p-STAT3 and c-MYC is involved in the pathogenesis of various solid tumors, but its prognostic value is still unclear in non-small cell lung cancer (NSCLC). Here, we sought to evaluate the expression and prognostic role of these markers in patients with lung adenocarcinoma (AD) and squamous cell carcinoma (SCC). Real time RT-PCR and Western blotting was used to analyze the mRNA and protein expression of PIM1 in NSCLC cell lines, respectively. The expression of PIM1, p-STAT3, and c-MYC was immunohistochemically tested in archival tumor samples from 194 lung AD and SCC patients. High nuclear PIM1 expression was detected in 43.3% of ADs and SCCs, and was significantly correlated with lymph node (LN) metastasis (P = 0.028) and histology (P = 0.003). High nuclear PIM1 expression (P = 0.034), locally advanced stage (P < 0.001), AD (P = 0.007) and poor pathologic differentiation (P = 0.002) were correlated with worse disease-free survival (DFS). High nuclear PIM1 expression (P = 0.009), advanced clinical stage (P < 0.001) and poor pathologic differentiation (P = 0.004) were independent unfavorable prognostic factors for overall survival (OS). High p-STAT3 expression was not associated with OS but significantly correlated with LN metastasis, while c-MYC was not significantly correlated with any clinicopathological parameter or survival. Therefore, in AD and SCC patients, nuclear PIM1 expression level is an independent factor for DFS and OS and it might serve as a predictive biomarker for outcome.
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Affiliation(s)
- Richeng Jiang
- 1. Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer;; 2. Key Laboratory of Cancer Prevention and Therapy, Tianjin;; 3. Department of Thoracic Oncology, Tianjin Lung Cancer Center, Tianjin Cancer Institute & Hospital, Tianjin Medical University, Tianjin 300060, PR China
| | - Xinyue Wang
- 1. Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer;; 2. Key Laboratory of Cancer Prevention and Therapy, Tianjin;; 3. Department of Thoracic Oncology, Tianjin Lung Cancer Center, Tianjin Cancer Institute & Hospital, Tianjin Medical University, Tianjin 300060, PR China
| | - Ziliang Jin
- 4. Department of Radiotherapy, the Second Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, PR China
| | - Kai Li
- 1. Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer;; 2. Key Laboratory of Cancer Prevention and Therapy, Tianjin;; 3. Department of Thoracic Oncology, Tianjin Lung Cancer Center, Tianjin Cancer Institute & Hospital, Tianjin Medical University, Tianjin 300060, PR China
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Jhaveri K, Teplinsky E, Silvera D, Valeta-Magara A, Arju R, Giashuddin S, Sarfraz Y, Alexander M, Darvishian F, Levine PH, Hashmi S, Zolfaghari L, Hoffman HJ, Singh B, Goldberg JD, Hochman T, Formenti S, Esteva FJ, Moran MS, Schneider RJ. Hyperactivated mTOR and JAK2/STAT3 Pathways: Molecular Drivers and Potential Therapeutic Targets of Inflammatory and Invasive Ductal Breast Cancers After Neoadjuvant Chemotherapy. Clin Breast Cancer 2015; 16:113-22.e1. [PMID: 26774497 DOI: 10.1016/j.clbc.2015.11.006] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Revised: 11/09/2015] [Accepted: 11/12/2015] [Indexed: 01/02/2023]
Abstract
INTRODUCTION Inflammatory breast cancer (IBC) is an aggressive and rare cancer with a poor prognosis and a need for novel targeted therapeutic strategies. Preclinical IBC data showed strong activation of the phosphatidylinositide-3-kinase/mammalian target of rapamycin (mTOR) and Janus kinase (JAK)/signal transducer and activator of transcription (STAT) pathways, and expression of inflammatory cytokines and tumor-associated macrophages (TAMs). PATIENTS AND METHODS Archival tumor tissue from 3 disease types (IBC treated with neoadjuvant chemotherapy [NAC], n = 45; invasive ductal carcinoma [IDC] treated with NAC [n = 24; 'treated IDC'; and untreated IDC [n = 27; 'untreated IDC']) was analyzed for the expression of biomarkers phospho-S6 (pS6) (mTOR), phospho-JAK2 (pJAK2), pSTAT3, interleukin (IL)-6, CD68 (monocytes, macrophages), and CD163 (TAMs). Surrounding nontumor tissue was also analyzed. RESULTS Biomarker levels and surrogate activity according to site-specific phosphorylation were shown in the tumor tissue of all 3 disease types but were greatest in IBC and treated IDC and least in untreated IDC for pS6, pJAK2, pSTAT3, and IL-6. Of 37 IBC patients with complete biomarker data available, 100% were pS6-positive and 95% were pJAK2-positive. In nontumor tissue, biomarker levels were observed in all groups but were generally greatest in untreated IDC and least in IBC, except for JAK2. CONCLUSION IBC and treated IDC display similar levels of mTOR and JAK2 biomarker activation, which suggests a potential mechanism of resistance after NAC. Biomarker levels in surrounding nontumor tissue suggested that the stroma might be activated by chemotherapy and resembles the oncogenic tumor-promoting environment. Activation of pS6 and pJAK2 in IBC might support dual targeting of the mTOR and JAK/STAT pathways, and the need for prospective studies to investigate combined targeted therapies in IBC.
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Affiliation(s)
- Komal Jhaveri
- Laura and Isaac Perlmutter Cancer Center, New York University Langone Medical Center, New York, NY.
| | - Eleonora Teplinsky
- Division of Hematology & Medical Oncology, Department of Medicine, New York University School of Medicine, New York, NY
| | - Deborah Silvera
- Department of Microbiology, New York University School of Medicine, New York, NY
| | - Amanda Valeta-Magara
- Department of Microbiology, New York University School of Medicine, New York, NY
| | - Rezina Arju
- Department of Microbiology, New York University School of Medicine, New York, NY
| | - Shah Giashuddin
- Department of Pathology, The Brooklyn Hospital Center, Brooklyn, NY
| | - Yasmeen Sarfraz
- Department of Microbiology, New York University School of Medicine, New York, NY
| | | | | | - Paul H Levine
- Department of Epidemiology and Biostatistics, George Washington University, Washington, DC
| | - Salman Hashmi
- Division of Biostatistics, New York University School of Medicine, New York, NY
| | - Ladan Zolfaghari
- Division of Biostatistics, New York University School of Medicine, New York, NY
| | - Heather J Hoffman
- Division of Biostatistics, New York University School of Medicine, New York, NY
| | - Baljit Singh
- Department of Epidemiology and Biostatistics, George Washington University, Washington, DC
| | - Judith D Goldberg
- Division of Biostatistics, New York University School of Medicine, New York, NY
| | - Tsivia Hochman
- Division of Biostatistics, New York University School of Medicine, New York, NY
| | - Silvia Formenti
- Department of Radiation Oncology, Weill Cornell Medical College, New York, NY
| | - Francisco J Esteva
- Laura and Isaac Perlmutter Cancer Center, New York University Langone Medical Center, New York, NY
| | - Meena S Moran
- Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, CT
| | - Robert J Schneider
- Laura and Isaac Perlmutter Cancer Center, New York University Langone Medical Center, New York, NY; Department of Microbiology, New York University School of Medicine, New York, NY
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Banerjee K, Resat H. Constitutive activation of STAT3 in breast cancer cells: A review. Int J Cancer 2015; 138:2570-8. [PMID: 26559373 DOI: 10.1002/ijc.29923] [Citation(s) in RCA: 428] [Impact Index Per Article: 47.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Accepted: 10/29/2015] [Indexed: 12/19/2022]
Abstract
Signal transducer and activator of transcription 3 (STAT3) is constitutively activated in numerous cancer types, including more than 40% of breast cancers. In contrast to tight regulation of STAT3 as a latent transcription factor in normal cells, its signaling in breast cancer oncogenesis is multifaceted. Signaling through the IL-6/JAK/STAT3 pathway initiated by the binding of IL-6 family of cytokines (i.e., IL-6 and IL-11) to their receptors have been implicated in breast cancer development. Receptors with intrinsic kinase activity such as EGFR and VEGFR directly or indirectly induce STAT3 activation in various breast cancer types. Aberrant STAT3 signaling promotes breast tumor progression through deregulation of the expression of downstream target genes which control proliferation (Bcl-2, Bcl-xL, Survivin, Cyclin D1, c-Myc and Mcl-1), angiogenesis (Hif1α and VEGF) and epithelial-mesenchymal transition (Vimentin, TWIST, MMP-9 and MMP-7). These multiple modes of STAT3 regulation therefore make it a central linking point for a multitude of signaling processes. Extensive efforts to target STAT3 activation in breast cancer had no remarkable success in the past because the highly interconnected nature of STAT3 signaling introduces lack of selectivity in pathway identification for STAT3 targeted molecular therapies or because its role in tumorigenesis may not be as critical as it was thought. This review provides a full spectrum of STAT3's involvement in breast cancer by consolidating the knowledge about its role in breast cancer development at multiple levels: its differential regulation by different receptor signaling pathways, its downstream target genes, and modification of its transcriptional activity by its coregulatory transcription factors.
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Affiliation(s)
- Kasturi Banerjee
- The Gene and Linda Voiland School of Chemical Engineering and Bioengineering, Washington State University, Pullman, WA
| | - Haluk Resat
- The Gene and Linda Voiland School of Chemical Engineering and Bioengineering, Washington State University, Pullman, WA
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Abroun S, Saki N, Ahmadvand M, Asghari F, Salari F, Rahim F. STATs: An Old Story, Yet Mesmerizing. Cell J 2015; 17:395-411. [PMID: 26464811 PMCID: PMC4601860 DOI: 10.22074/cellj.2015.1] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/02/2013] [Accepted: 08/07/2014] [Indexed: 01/01/2023]
Abstract
Signal transducers and activators of transcription (STATs) are cytoplasmic transcription factors that have a key role in cell fate. STATs, a protein family comprised of
seven members, are proteins which are latent cytoplasmic transcription factors that
convey signals from the cell surface to the nucleus through activation by cytokines
and growth factors. The signaling pathways have diverse biological functions that
include roles in cell differentiation, proliferation, development, apoptosis, and inflammation which place them at the center of a very active area of research. In this review we explain Janus kinase (JAK)/STAT signaling and focus on STAT3, which is
transient from cytoplasm to nucleus after phosphorylation. This procedure controls
fundamental biological processes by regulating nuclear genes controlling cell proliferation, survival, and development. In some hematopoietic disorders and cancers,
overexpression and activation of STAT3 result in high proliferation, suppression of
cell differentiation and inhibition of cell maturation. This article focuses on STAT3
and its role in malignancy, in addition to the role of microRNAs (miRNAs) on STAT3
activation in certain cancers.
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Affiliation(s)
- Saeid Abroun
- Department of Hematology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Najmaldin Saki
- Health Research Institute, Research Center of Thalassemia and Hemoglobinopathy, Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Mohammad Ahmadvand
- Department of Hematology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Farahnaz Asghari
- Department of Medicine II, Division of Gastroenterology, University of Rostock, E.Heydemann-Strasse 6, Rostock, Germany
| | - Fatemeh Salari
- Health Research Institute, Research Center of Thalassemia and Hemoglobinopathy, Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Fakher Rahim
- Health Research Institute, Hearing Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
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Kim JY, Lim SC, Kim G, Yun HJ, Ahn SG, Choi HS. Interleukin-33/ST2 axis promotes epithelial cell transformation and breast tumorigenesis via upregulation of COT activity. Oncogene 2015. [PMID: 25531326 DOI: 10.1038/onc.2014.418.] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Cytokines of the interleukin-1 (IL-1) family, such as IL-1α/β and IL-18, have pleiotropic activities in innate and adaptive immune responses in host defense and diseases. Insight into their biological functions helped develop novel therapeutic approaches to treat human inflammatory diseases. IL-33 is an important member of the IL-1 family of cytokines and is a ligand of the ST2 receptor, a member of the IL-1 receptor family. However, the role of the IL-33/ST2 axis in tumor growth and metastasis of breast cancer remains unclear. Here, we demonstrate that IL-33 is a critical tumor promoter during epithelial cell proliferation and tumorigenesis in the breast. IL-33 dose- and time-dependently increased Cancer Osaka Thyroid (COT) phosphorylation via ST2-COT interaction in normal epithelial and breast cancer cells. The IL-33/ST2/COT cascade induced the activation of the MEK-ERK (MEK-extracellular signal-regulated kinase), JNK-cJun (cJun N-terminal kinase-cJun) and STAT3 (signal transducer and activator of transcription 3) signaling pathways, followed by increased AP-1 and stat3 transcriptional activity. When small interfering RNAs of ST2 and COT were introduced into cells, IL-33-induced AP-1 and stat3 activity were significantly decreased, unlike that in the control cells. The inhibition of COT activity resulted in decreased IL-33-induced epithelial cell transformation, and knockdown of IL-33, ST2 and COT in breast cancer cells attenuated tumorigenicity of breast cancer cells. Consistent with these observations, ST2 levels were positively correlated with COT expression in human breast cancer. These findings provide a novel perspective on the role of the IL-33/ST2/COT signaling pathway in supporting cancer-associated inflammation in the tumor microenvironment. Therapeutic approaches that target this pathway may, therefore, effectively inhibit carcinogenesis in the breast.
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Affiliation(s)
- J Y Kim
- College of Pharmacy, Chosun University, Gwangju, South Korea
| | - S-C Lim
- Department of Pathology, School of Medicine, Chosun University, Gwangju, South Korea
| | - G Kim
- College of Pharmacy, Chosun University, Gwangju, South Korea
| | - H J Yun
- College of Pharmacy, Chosun University, Gwangju, South Korea
| | - S-G Ahn
- Department of Pathology, School of Dentistry, Chosun University, Gwangju, South Korea
| | - H S Choi
- College of Pharmacy, Chosun University, Gwangju, South Korea
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Kim JY, Lim SC, Kim G, Yun HJ, Ahn SG, Choi HS. Interleukin-33/ST2 axis promotes epithelial cell transformation and breast tumorigenesis via upregulation of COT activity. Oncogene 2015; 34:4928-38. [PMID: 25531326 DOI: 10.1038/onc.2014.418] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [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: 05/07/2014] [Revised: 10/08/2014] [Accepted: 10/31/2014] [Indexed: 02/07/2023]
Abstract
Cytokines of the interleukin-1 (IL-1) family, such as IL-1α/β and IL-18, have pleiotropic activities in innate and adaptive immune responses in host defense and diseases. Insight into their biological functions helped develop novel therapeutic approaches to treat human inflammatory diseases. IL-33 is an important member of the IL-1 family of cytokines and is a ligand of the ST2 receptor, a member of the IL-1 receptor family. However, the role of the IL-33/ST2 axis in tumor growth and metastasis of breast cancer remains unclear. Here, we demonstrate that IL-33 is a critical tumor promoter during epithelial cell proliferation and tumorigenesis in the breast. IL-33 dose- and time-dependently increased Cancer Osaka Thyroid (COT) phosphorylation via ST2-COT interaction in normal epithelial and breast cancer cells. The IL-33/ST2/COT cascade induced the activation of the MEK-ERK (MEK-extracellular signal-regulated kinase), JNK-cJun (cJun N-terminal kinase-cJun) and STAT3 (signal transducer and activator of transcription 3) signaling pathways, followed by increased AP-1 and stat3 transcriptional activity. When small interfering RNAs of ST2 and COT were introduced into cells, IL-33-induced AP-1 and stat3 activity were significantly decreased, unlike that in the control cells. The inhibition of COT activity resulted in decreased IL-33-induced epithelial cell transformation, and knockdown of IL-33, ST2 and COT in breast cancer cells attenuated tumorigenicity of breast cancer cells. Consistent with these observations, ST2 levels were positively correlated with COT expression in human breast cancer. These findings provide a novel perspective on the role of the IL-33/ST2/COT signaling pathway in supporting cancer-associated inflammation in the tumor microenvironment. Therapeutic approaches that target this pathway may, therefore, effectively inhibit carcinogenesis in the breast.
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Affiliation(s)
- J Y Kim
- College of Pharmacy, Chosun University, Gwangju, South Korea
| | - S-C Lim
- Department of Pathology, School of Medicine, Chosun University, Gwangju, South Korea
| | - G Kim
- College of Pharmacy, Chosun University, Gwangju, South Korea
| | - H J Yun
- College of Pharmacy, Chosun University, Gwangju, South Korea
| | - S-G Ahn
- Department of Pathology, School of Dentistry, Chosun University, Gwangju, South Korea
| | - H S Choi
- College of Pharmacy, Chosun University, Gwangju, South Korea
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Castillo-Lluva S, Hontecillas-Prieto L, Blanco-Gómez A, Del Mar Sáez-Freire M, García-Cenador B, García-Criado J, Pérez-Andrés M, Orfao A, Cañamero M, Mao JH, Gridley T, Castellanos-Martín A, Pérez-Losada J. A new role of SNAI2 in postlactational involution of the mammary gland links it to luminal breast cancer development. Oncogene 2015; 34:4777-90. [PMID: 26096931 PMCID: PMC4560637 DOI: 10.1038/onc.2015.224] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2014] [Revised: 04/25/2015] [Accepted: 05/16/2015] [Indexed: 12/30/2022]
Abstract
Breast cancer is a major cause of mortality in women. The transcription factor SNAI2 has been implicated in the pathogenesis of several types of cancer, including breast cancer of basal origin. Here we show that SNAI2 is also important in the development of breast cancer of luminal origin in MMTV-ErbB2 mice. SNAI2 deficiency leads to longer latency and fewer luminal tumors, both of these being characteristics of pretumoral origin. These effects were associated with reduced proliferation and a decreased ability to generate mammospheres in normal mammary glands. However, the capacity to metastasize was not modified. Under conditions of increased ERBB2 oncogenic activity after pregnancy plus SNAI2 deficiency, both pretumoral defects-latency and tumor load-were compensated. However, the incidence of lung metastases was dramatically reduced. Furthermore, SNAI2 was required for proper postlactational involution of the breast. At 3 days post lactational involution, the mammary glands of Snai2-deficient mice exhibited lower levels of pSTAT3 and higher levels of pAKT1, resulting in decreased apoptosis. Abundant noninvoluted ducts were still present at 30 days post lactation, with a greater number of residual ERBB2+ cells. These results suggest that this defect in involution leads to an increase in the number of susceptible target cells for transformation, to the recovery of the capacity to generate mammospheres and to an increase in the number of tumors. Our work demonstrates the participation of SNAI2 in the pathogenesis of luminal breast cancer, and reveals an unexpected connection between the processes of postlactational involution and breast tumorigenesis in Snai2-null mutant mice.
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Affiliation(s)
- S Castillo-Lluva
- Instituto de Biología Molecular y Celular del Cáncer (IBMCC), Universidad de Salamanca/CSIC, Salamanca, Spain
- Instituto de Investigación Biomédica de Salamanca (IBSAL), Hospital Universitario de Salamanca, Salamanca, Spain
| | - L Hontecillas-Prieto
- Instituto de Biología Molecular y Celular del Cáncer (IBMCC), Universidad de Salamanca/CSIC, Salamanca, Spain
- Instituto de Investigación Biomédica de Salamanca (IBSAL), Hospital Universitario de Salamanca, Salamanca, Spain
| | - A Blanco-Gómez
- Instituto de Biología Molecular y Celular del Cáncer (IBMCC), Universidad de Salamanca/CSIC, Salamanca, Spain
- Instituto de Investigación Biomédica de Salamanca (IBSAL), Hospital Universitario de Salamanca, Salamanca, Spain
| | - M Del Mar Sáez-Freire
- Instituto de Biología Molecular y Celular del Cáncer (IBMCC), Universidad de Salamanca/CSIC, Salamanca, Spain
- Instituto de Investigación Biomédica de Salamanca (IBSAL), Hospital Universitario de Salamanca, Salamanca, Spain
| | - B García-Cenador
- Instituto de Investigación Biomédica de Salamanca (IBSAL), Hospital Universitario de Salamanca, Salamanca, Spain
- Departamento de Cirugía, Universidad de Salamanca, Salamanca, Spain
| | - J García-Criado
- Instituto de Investigación Biomédica de Salamanca (IBSAL), Hospital Universitario de Salamanca, Salamanca, Spain
- Departamento de Cirugía, Universidad de Salamanca, Salamanca, Spain
| | - M Pérez-Andrés
- Instituto de Biología Molecular y Celular del Cáncer (IBMCC), Universidad de Salamanca/CSIC, Salamanca, Spain
- Instituto de Investigación Biomédica de Salamanca (IBSAL), Hospital Universitario de Salamanca, Salamanca, Spain
- Unidad de Citometría de flujo, Universidad de Salamanca, IBSAL, Salamanca, Spain
| | - A Orfao
- Instituto de Biología Molecular y Celular del Cáncer (IBMCC), Universidad de Salamanca/CSIC, Salamanca, Spain
- Instituto de Investigación Biomédica de Salamanca (IBSAL), Hospital Universitario de Salamanca, Salamanca, Spain
- Unidad de Citometría de flujo, Universidad de Salamanca, IBSAL, Salamanca, Spain
| | - M Cañamero
- Centro Nacional de Investigaciones Oncológicas (CNIO), Madrid, Spain
| | - J H Mao
- Life Sciences Division, Lawrence Berkeley National Laboratory (LBNL), University of California, Berkeley, Berkeley, CA, USA
| | - T Gridley
- Center for Molecular Medicine, Maine Medical Center Research Institute, Scarborough, ME, USA
| | - A Castellanos-Martín
- Instituto de Biología Molecular y Celular del Cáncer (IBMCC), Universidad de Salamanca/CSIC, Salamanca, Spain
- Instituto de Investigación Biomédica de Salamanca (IBSAL), Hospital Universitario de Salamanca, Salamanca, Spain
| | - J Pérez-Losada
- Instituto de Biología Molecular y Celular del Cáncer (IBMCC), Universidad de Salamanca/CSIC, Salamanca, Spain
- Instituto de Investigación Biomédica de Salamanca (IBSAL), Hospital Universitario de Salamanca, Salamanca, Spain
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Rodriguez-Barrueco R, Yu J, Saucedo-Cuevas LP, Olivan M, Llobet-Navas D, Putcha P, Castro V, Murga-Penas EM, Collazo-Lorduy A, Castillo-Martin M, Alvarez M, Cordon-Cardo C, Kalinsky K, Maurer M, Califano A, Silva JM. Inhibition of the autocrine IL-6-JAK2-STAT3-calprotectin axis as targeted therapy for HR-/HER2+ breast cancers. Genes Dev 2015; 29:1631-48. [PMID: 26227964 PMCID: PMC4536311 DOI: 10.1101/gad.262642.115] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2015] [Accepted: 07/14/2015] [Indexed: 12/22/2022]
Abstract
Rodriguez-Barrueco et al. found that HR−/HER2+ cells secrete high levels of IL-6, inducing the activation of STAT3, which in turn promotes a second autocrine stimulus to increase S100A8/9 complex (calprotectin) production and secretion. Inhibition of the IL-6–JAK2–STAT3–calprotectin axis with FDA-approved drugs, alone and in combination with HER2 inhibitors, reduced the tumorigenicity of HR−/HER2+ breast cancers. HER2-positive (HER2+) breast adenocarcinomas are a heterogeneous group in which hormone receptor (HR) status influences therapeutic decisions and patient outcome. By combining genome-wide RNAi screens with regulatory network analysis, we identified STAT3 as a critically activated master regulator of HR−/HER2+ tumors, eliciting tumor dependency in these cells. Mechanistically, HR−/HER2+ cells secrete high levels of the interleukin-6 (IL-6) cytokine, inducing the activation of STAT3, which in turn promotes a second autocrine stimulus to increase S100A8/9 complex (calprotectin) production and secretion. Increased calprotectin levels activate signaling pathways involved in proliferation and resistance. Importantly, we demonstrated that inhibition of the IL-6–Janus kinase 2 (JAK2)–STAT3–calprotectin axis with FDA-approved drugs, alone and in combination with HER2 inhibitors, reduced the tumorigenicity of HR−/HER2+ breast cancers, opening novel targeted therapeutic opportunities.
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Affiliation(s)
- Ruth Rodriguez-Barrueco
- Department of Pathology, Icahn School of Medicine at Mount Sinai, New York, New York 10029, USA
| | - Jiyang Yu
- Department of Systems Biology, Center for Computational Biology and Bioinformatics, Columbia University, New York, New York 10032, USA; Herbert Irving Comprehensive Cancer Center, Columbia University, New York, New York 10032, USA
| | - Laura P Saucedo-Cuevas
- Department of Pathology, Icahn School of Medicine at Mount Sinai, New York, New York 10029, USA
| | - Mireia Olivan
- Department of Pathology, Icahn School of Medicine at Mount Sinai, New York, New York 10029, USA
| | - David Llobet-Navas
- Department of Pathology, Icahn School of Medicine at Mount Sinai, New York, New York 10029, USA
| | - Preeti Putcha
- Institute for Cancer Genetics, Department of Pathology, Irving Cancer Research Center, Columbia University, New York, New York 10032, USA
| | - Veronica Castro
- Institute for Cancer Genetics, Department of Pathology, Irving Cancer Research Center, Columbia University, New York, New York 10032, USA
| | - Eva M Murga-Penas
- Institute for Cancer Genetics, Department of Pathology, Irving Cancer Research Center, Columbia University, New York, New York 10032, USA
| | - Ana Collazo-Lorduy
- Department of Pathology, Icahn School of Medicine at Mount Sinai, New York, New York 10029, USA
| | - Mireia Castillo-Martin
- Department of Pathology, Icahn School of Medicine at Mount Sinai, New York, New York 10029, USA
| | - Mariano Alvarez
- Department of Systems Biology, Center for Computational Biology and Bioinformatics, Columbia University, New York, New York 10032, USA; Herbert Irving Comprehensive Cancer Center, Columbia University, New York, New York 10032, USA
| | - Carlos Cordon-Cardo
- Department of Pathology, Icahn School of Medicine at Mount Sinai, New York, New York 10029, USA
| | - Kevin Kalinsky
- Department of Medicine, Columbia University Medical Center, New York, New York 10032, USA
| | - Matthew Maurer
- Institute for Cancer Genetics, Department of Pathology, Irving Cancer Research Center, Columbia University, New York, New York 10032, USA; Department of Medicine, Columbia University Medical Center, New York, New York 10032, USA
| | - Andrea Califano
- Department of Systems Biology, Center for Computational Biology and Bioinformatics, Columbia University, New York, New York 10032, USA; Herbert Irving Comprehensive Cancer Center, Columbia University, New York, New York 10032, USA; Department of Biomedical Informatics, Institute for Cancer Genetics, Columbia University, New York, New York 10032; Department of Biochemistry and Molecular Biophysics, Institute for Cancer Genetics, Columbia University, New York, New York 10032
| | - Jose M Silva
- Department of Pathology, Icahn School of Medicine at Mount Sinai, New York, New York 10029, USA
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Zhang H, Tang Y, Zhang Y, Zhang S, Qu J, Wang X, Kong R, Han C, Liu Z. Fucoxanthin: A Promising Medicinal and Nutritional Ingredient. Evid Based Complement Alternat Med 2015; 2015:723515. [PMID: 26106437 DOI: 10.1155/2015/723515] [Citation(s) in RCA: 81] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/04/2015] [Accepted: 05/04/2015] [Indexed: 12/30/2022]
Abstract
Fucoxanthin, an allenic carotenoid, can be isolated from edible brown seaweeds. Recent studies have reported that fucoxanthin has many physiological functions and biological properties, such as antiobesity, antitumor, antidiabetes, antioxidant, anti-inflammatory, and hepatoprotective activities, as well as cardiovascular and cerebrovascular protective effects. Therefore, fucoxanthin can be used as both medicinal and nutritional ingredient to prevent and treat chronic diseases. Although fucoxanthin possesses many medicinal ingredient and nutritional qualities, studies indicated that its structure was unstable. In this paper, we consulted the current documents and reviewed structural properties and factors affecting the stability of fucoxanthin. We also reported the metabolism, safety, pharmacological activities, and the methods of improving the bioavailability of fucoxanthin. Based on these studies providing essential background knowledge, fucoxanthin can be developed into marine drugs and nutritional products.
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Choi YK, Cho SG, Woo SM, Yun YJ, Park S, Shin YC, Ko SG. Herbal extract SH003 suppresses tumor growth and metastasis of MDA-MB-231 breast cancer cells by inhibiting STAT3-IL-6 signaling. Mediators Inflamm 2014; 2014:492173. [PMID: 24976685 DOI: 10.1155/2014/492173] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2014] [Revised: 05/08/2014] [Accepted: 05/09/2014] [Indexed: 12/31/2022] Open
Abstract
Cancer inflammation promotes cancer progression, resulting in a high risk of cancer. Here, we demonstrate that our new herbal extract, SH003, suppresses both tumor growth and metastasis of MDA-MB-231 breast cancer cells via inhibiting STAT3-IL-6 signaling path. Our new herbal formula, SH003, mixed extract from Astragalus membranaceus, Angelica gigas, and Trichosanthes kirilowii Maximowicz, suppressed MDA-MB-231 tumor growth and lung metastasis in vivo and reduced the viability and metastatic abilities of MDA-MB-231 cells in vitro. Furthermore, SH003 inhibited STAT3 activation, which resulted in a reduction of IL-6 production. Therefore, we conclude that SH003 suppresses highly metastatic breast cancer growth and metastasis by inhibiting STAT3-IL-6 signaling path.
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Avtanski DB, Nagalingam A, Bonner MY, Arbiser JL, Saxena NK, Sharma D. Honokiol inhibits epithelial-mesenchymal transition in breast cancer cells by targeting signal transducer and activator of transcription 3/Zeb1/E-cadherin axis. Mol Oncol 2014; 8:565-80. [PMID: 24508063 DOI: 10.1016/j.molonc.2014.01.004] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2013] [Revised: 01/06/2014] [Accepted: 01/07/2014] [Indexed: 12/22/2022] Open
Abstract
Epithelial-mesenchymal transition (EMT), a critical step in the acquisition of metastatic state, is an attractive target for therapeutic interventions directed against tumor metastasis. Honokiol (HNK) is a natural phenolic compound isolated from an extract of seed cones from Magnolia grandiflora. Recent studies from our lab show that HNK impedes breast carcinogenesis. Here, we provide molecular evidence that HNK inhibits EMT in breast cancer cells resulting in significant downregulation of mesenchymal marker proteins and concurrent upregulation of epithelial markers. Experimental EMT induced by exposure to TGFβ and TNFα in spontaneously immortalized nontumorigenic human mammary epithelial cells is also completely reversed by HNK as evidenced by morphological as well as molecular changes. Investigating the downstream mediator(s) that may direct EMT inhibition by HNK, we found functional interactions between HNK, Stat3, and EMT-signaling components. In vitro and in vivo analyses show that HNK inhibits Stat3 activation in breast cancer cells and tumors. Constitutive activation of Stat3 abrogates HNK-mediated activation of epithelial markers whereas inhibition of Stat3 using small molecule inhibitor, Stattic, potentiates HNK-mediated inhibition of EMT markers, invasion and migration of breast cancer cells. Mechanistically, HNK inhibits recruitment of Stat3 on mesenchymal transcription factor Zeb1 promoter resulting in decreased Zeb1 expression and nuclear translocation. We also discover that HNK increases E-cadherin expression via Stat3-mediated release of Zeb1 from E-cadherin promoter. Collectively, this study reports that HNK effectively inhibits EMT in breast cancer cells and provide evidence for a previously unrecognized cross-talk between HNK and Stat3/Zeb1/E-cadherin axis.
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Affiliation(s)
- Dimiter B Avtanski
- Department of Oncology, Johns Hopkins University School of Medicine, The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore, MD 21231, USA
| | - Arumugam Nagalingam
- Department of Oncology, Johns Hopkins University School of Medicine, The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore, MD 21231, USA
| | - Michael Y Bonner
- Department of Dermatology, Emory University School of Medicine, Winship Cancer Institute, Atlanta, GA 30322, USA
| | - Jack L Arbiser
- Department of Dermatology, Emory University School of Medicine, Winship Cancer Institute, Atlanta, GA 30322, USA; Atlanta Veterans Administration Medical Center, Atlanta, GA 30322, USA
| | - Neeraj K Saxena
- Department of Medicine, University of Maryland School of Medicine, 660 W Redwood St., Howard Hall, Rm 301, Baltimore, MD 21201, USA.
| | - Dipali Sharma
- Department of Oncology, Johns Hopkins University School of Medicine, The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore, MD 21231, USA.
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21
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Hogstrand C, Kille P, Ackland ML, Hiscox S, Taylor KM. A mechanism for epithelial-mesenchymal transition and anoikis resistance in breast cancer triggered by zinc channel ZIP6 and STAT3 (signal transducer and activator of transcription 3). Biochem J 2013; 455:229-37. [PMID: 23919497 DOI: 10.1042/BJ20130483] [Citation(s) in RCA: 80] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Genes involved in normal developmental processes attract attention as mediators of tumour progression as they facilitate migration of tumour cells. EMT (epithelial–mesenchymal transition), an essential part of embryonic development, tissue remodelling and wound repair, is crucial for tumour metastasis. Previously, zinc transporter ZIP6 [SLC39A6; solute carrier family 39 (zinc transporter), member 6; also known as LIV-1) was linked to EMT in zebrafish gastrulation through a STAT3 (signal transducer and activator of transcription 3) mechanism, resulting in nuclear localization of transcription factor Snail. In the present study, we show that zinc transporter ZIP6 is transcriptionally induced by STAT3 and unprecedented among zinc transporters, and is activated by N-terminal cleavage which triggers ZIP6 plasma membrane location and zinc influx. This zinc influx inactivates GSK-3β (glycogen synthase kinase 3β), either indirectly or directly via Akt or GSK-3β respectively, resulting in activation of Snail, which remains in the nucleus and acts as a transcriptional repressor of E-cadherin (epithelial cadherin), CDH1, causing cell rounding and detachment. This was mirrored by ZIP6-transfected cells which underwent EMT, detached from monolayers and exhibited resistance to anoikis by their ability to continue proliferating even after detachment. Our results indicate a causative role for ZIP6 in cell motility and migration, providing ZIP6 as a new target for prediction of clinical cancer spread and also suggesting a ZIP6-dependent mechanism of tumour metastasis. We demonstrate a novel mechanism for the ability of cellular zinc to drive cell detachment and migration with implications for breast cancer spread. This mechanism involves a zinc uptake channel ZIP6 (also known as SLC39A6) and a transcription factor, STAT3.
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Abstract
During the last decades a large number of cucurbitacins have been isolated from various plant species belonging to other plant families than Cucurbitaceae. Although the roots and the fruits of plant belong to these Cucurbitaceae species are very bitter, they have been used as folk medicines in some countries because of their wide spectrum of pharmacological activities such as anti-inflammation and anticancer effects. In the last ten years, cucurbitacins had been shown to inhibit proliferation and induced apoptosis utilizing a long array of in vitro and in vivo cancer cell models. Several molecular targets for cucurbitacins have been discovered, such as fibrous-actin, signal transducer and activator of transcription (STAT), cyclooxygenase-2, etc. This review aimed at elucidating the natural sources of some cucurbitacin compounds, their chemical structure and derivatives, physical properties, biological activities and mechanism by which they reduce the proliferation human cancer cells. This widens our armaments against a devastating disease that we are failing to face.
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Abstract
MUC1 is a transmembrane mucin that is often overexpressed in metastatic cancers and often used as a diagnostic marker for metastatic progression. The extracellular domain of MUC1 can serve as a ligand for stromal and endothelial cell adhesion receptors, and the cytoplasmic domain engages in several interactions that can result in increased migration and invasion, as well as survival. In this review, we address the role of MUC1 in metastatic progression by assessing clinical studies reporting MUC1 levels at various disease stages, reviewing mouse models utilized to study the role of MUC1 in metastatic progression, discuss mechanisms of MUC1 upregulation, and detail MUC1 protein interactions and signaling events. We review interactions between MUC1 and the extracellular environment, with proteins colocalized in the plasma membrane and/or cytoplasmic proteins, and summarize the role of MUC1 in the nucleus as a transcriptional cofactor. Finally, we review recent publications describing current therapies targeting MUC1 in patients with advanced disease and the stage of these therapies in preclinical development or clinical trials.
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Affiliation(s)
- Teresa M Horm
- Department of Molecular and Cellular Biology, Arizona Cancer Center and BIO5 Institute, University of Arizona, Tucson, AZ, USA
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Wang J, Chen S, Xu S, Yu X, Ma D, Hu X, Cao X. In vivo induction of apoptosis by fucoxanthin, a marine carotenoid, associated with down-regulating STAT3/EGFR signaling in sarcoma 180 (S180) xenografts-bearing mice. Mar Drugs 2012; 10:2055-2068. [PMID: 23118721 PMCID: PMC3475273 DOI: 10.3390/md10092055] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2012] [Revised: 08/17/2012] [Accepted: 09/10/2012] [Indexed: 12/11/2022] Open
Abstract
Previous in vitro researches have showed that fucoxanthin, a natural carotenoid isolated from sargassum, can inhibit proliferation or induce apoptosis in human neuroblastoma, hepatoma, leukemia, colon carcinoma, prostate cancer or urinary bladder cancer cells. But the precise mechanism by which fucoxanthin exerts anticarcinogenic effects is not yet fully understood. In this study, we performed an in vivo study to investigate the anti-tumor effect and mechanisms of fucoxanthin on xenografted sarcoma 180 (S180) in mice. Results revealed that fucoxanthin significantly inhibited the growth of sarcoma at the dose of 50 or 100 mg/kg. TUNEL analysis showed that the number of positive cells in the fucoxanthin-treated group was higher than that in the control group. Western blotting analysis also revealed the suppressed expression of bcl-2 and enhanced expression of cleaved caspase-3 by fucoxanthin. In addition, immunohistochemistry analysis and Western blotting analysis showed that fucoxanthin significantly decreased the expressions of survivin and vascular endothelial growth factor (VEGF). Most importantly, fucoxanthin inhibited the expressions of the epidermal growth factor receptor (EGFR) and STAT3 and phosphorylated STAT3 proteins. These results indicated that in vivo induction of apoptosis by fucoxanthin is associated with down-regulating STAT3/EGFR signaling in S180 xenografts-bearing mice.
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Affiliation(s)
| | | | | | | | | | - Xiamin Hu
- Author to whom correspondence should be addressed; ; Tel.: +86-27-68893640; Fax: +86-27-68893590
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Sonnenblick A, Shriki A, Galun E, Axelrod JH, Daum H, Rottenberg Y, Hamburger T, Mali B, Peretz T. Tissue microarray-based study of patients with lymph node-positive breast cancer shows tyrosine phosphorylation of signal transducer and activator of transcription 3 (tyrosine705-STAT3) is a marker of good prognosis. Clin Transl Oncol 2012; 14:232-6. [PMID: 22374428 DOI: 10.1007/s12094-012-0789-z] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
BACKGROUND Although lymph node-positive breast cancers are associated with poorer prognosis, individual patients may have different clinical outcomes. Signal transducer and activator of transcription 3 (STAT3) is a point of convergence for numerous oncogenic signalling pathways. The goal of this study was to determine the prognostic value of phosphorylated (tyrosine705)-STAT3 in node-positive breast cancer patients. METHODS Immunohistochemical analysis of Phospho- STAT3 was performed on a tissue microarray of breast cancer specimens. The expression pattern of Phospho-STAT3 was correlated with survival outcome, and clinical and pathological parameters. RESULTS Out of 125 interpretable tumours, positive Phospho- STAT3 nuclear expression was seen in 35 (28%) of tumours. There was no significant relationship between Phospho-STAT3 expression and clinical-pathological parameters including age, hormonal receptor status, grade and tumour size. Interestingly positive tumours had a significantly improved disease-free survival at 5 years (p=0.035). Additionally, positive Phospho-STAT3 nuclear expression was correlated with significantly improved survival at both 5 years (p=0.023) and 10 years (p=0.026). Finally, in multivariate analyses Phospho-STAT3 was found to be an independent prognostic marker of overall survival in node-positive breast cancer patients. CONCLUSION These findings support the role of Phospho- STAT3 as an important independent prognostic marker in node-positive breast cancer patients.
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Affiliation(s)
- Amir Sonnenblick
- Sharett Institute of Oncology, Hadassah-Hebrew University Medical Center, Ein Kerem, POB 12000, Jerusalem 91120, Israel.
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You Z, Xu D, Ji J, Guo W, Zhu W, He J. JAK/STAT signal pathway activation promotes progression and survival of human oesophageal squamous cell carcinoma. Clin Transl Oncol 2012; 14:143-9. [PMID: 22301404 DOI: 10.1007/s12094-012-0774-6] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVE Inappropriate activation of JAK/STAT pathway occurs with high frequency in human cancers and is associated with cancer cell survival and proliferation. However, its role in oesophageal squamous cell carcinoma (ESCC) is unknown. METHODS By immunohistochemistry, we analysed the expression of two components of this pathway, phosphorylated JAK-1 (pJAK-1) and phosphorylated STAT-3 (pSTAT-3), in 100 ESCC tumours and paired non-neoplastic oesophageal epithelia. Kaplan-Meier survival and Cox regression analyses were performed to evaluate the prognosis of patients. RESULTS We found that pJAK-1 and pSTAT-3 expression was not detectable in normal oesophageal squamous cells. Primary ESCC with pJAK-1-positive and pSTAT-3-positive expression was detected in the cancer cell nests of 78 and 72 cases, respectively. In addition, the Pearson's correlation coefficient between pJAK-1 and pSTAT-3 expression was 0.806 (p<0.001). Moreover, pJAK-1 and pSTAT-3 expression was correlated with N stage (lymph node metastasis, both p=0.01), pTNM stage (p=0.008 and 0.009, respectively) and metastatic status (both p=0.01). Furthermore, pJAK-1 and pSTAT-3 expression was associated with shorter overall survival (both p<0.001) and shorter disease-free survival (p=0.005 and 0.006, respectively). By multivariate analysis, TNM clinical classification (T, p<0.001; N, p=0.002; M, p=0.02), pJAK-1 (p=0.002) and pSTAT-3 (p=0.003) were independent prognosis predictors of ESCC. CONCLUSION These results provide convincing evidence for the first time that the JAK/STAT pathway may participate in the progress of ESCC.
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Affiliation(s)
- Zhenbing You
- Department of Chest Surgery, First Hospital of Huaian, Nanjing Medical University, Huaian 223300, China
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Wang X, Wang G, Zhao Y, Liu X, Ding Q, Shi J, Ding Y, Wang S. STAT3 mediates resistance of CD44(+)CD24(-/low) breast cancer stem cells to tamoxifen in vitro. J Biomed Res 2012; 26:325-35. [PMID: 23554768 PMCID: PMC3597778 DOI: 10.7555/jbr.26.20110050] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2011] [Revised: 07/31/2011] [Accepted: 11/07/2011] [Indexed: 01/17/2023] Open
Abstract
We sought to determine whether STAT3 mediated tamoxifen resistance of breast cancer stem cells in vitro. The capacities for mammosphere formation and STAT3 expression of CD44+CD24−/low MCF-7 and MCF-7 were observed. The CD44+CD24−/low subpopulation ratio and its sensitivity to adriamycin were analyzed in MCF-7 and TAM resistant (TAM-R) cells. Cell cycle, apoptosis, STAT3 and phospho-STAT3 changes were observed after treatment with tamoxifen. Small interference RNA-mediated knockdown of STAT3 in TAM-R cells was also performed. CD44+CD24−/low MCF-7 showed higher capacities for mammosphere formation and STAT3 expression than total MCF-7. The CD44+CD24−/low subpopulation was also upregulated in TAM-R cells with less sensitivity to adriamycin than MCF-7. Cell cycle changes, anti-apoptotic effects and STAT3 changes were also found. Meanwhile, the knock-down of STAT3 in TAM-R resulted in an increase in sensitivity to tamoxifen. It is concluded that STAT3 plays an essential role in breast cancer stem cells, which correlated with tamoxifen resistance.
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Affiliation(s)
- Xiaoyan Wang
- Department of Breast Surgery, the First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, China
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Prasad S, Pandey MK, Yadav VR, Aggarwal BB. Gambogic acid inhibits STAT3 phosphorylation through activation of protein tyrosine phosphatase SHP-1: potential role in proliferation and apoptosis. Cancer Prev Res (Phila) 2011; 4:1084-94. [PMID: 21490133 DOI: 10.1158/1940-6207.capr-10-0340] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The transcription factor, STAT3, is associated with proliferation, survival, and metastasis of cancer cells. We investigated whether gambogic acid (GA), a xanthone derived from the resin of traditional Chinese medicine, Garcinia hanburyi (mangosteen), can regulate the STAT3 pathway, leading to suppression of growth and sensitization of cancer cells. We found that GA induced apoptosis in human multiple myeloma cells that correlated with the inhibition of both constitutive and inducible STAT3 activation. STAT3 phosphorylation at both tyrosine residue 705 and serine residue 727 was inhibited by GA. STAT3 suppression was mediated through the inhibition of activation of the protein tyrosine kinases Janus-activated kinase 1 (JAK1) and JAK2. Treatment with the protein tyrosine phosphatase (PTP) inhibitor pervanadate reversed the GA-induced downregulation of STAT3, suggesting the involvement of a PTP. We also found that GA induced the expression of the PTP SHP-1. Deletion of the SHP-1 gene by siRNA suppressed the ability of GA to inhibit STAT3 activation and to induce apoptosis, suggesting the critical role of SHP-1 in its action. Moreover, GA downregulated the expression of STAT3-regulated antiapoptotic (Bcl-2, Bcl-xL, and Mcl-1), proliferative (cyclin D1), and angiogenic (VEGF) proteins, and this correlated with suppression of proliferation and induction of apoptosis. Overall, these results suggest that GA blocks STAT3 activation, leading to suppression of tumor cell proliferation and induction of apoptosis.
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Affiliation(s)
- Sahdeo Prasad
- Cytokine Research Laboratory, Department of Experimental Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
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Bito T, Sumita N, Ashida M, Budiyanto A, Ueda M, Ichihashi M, Tokura Y, Nishigori C. Inhibition of Epidermal Growth Factor Receptor and PI3K/Akt Signaling Suppresses Cell Proliferation and Survival through Regulation of Stat3 Activation in Human Cutaneous Squamous Cell Carcinoma. J Skin Cancer 2011; 2011:874571. [PMID: 21197106 DOI: 10.1155/2011/874571] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2010] [Accepted: 10/11/2010] [Indexed: 01/10/2023] Open
Abstract
Recent studies have emphasized the important role of Stat3 activation in a number of human tumors from the viewpoint of its oncogenic and antiapoptotic activity. In this study, we examined the role and related signaling molecules of Stat3 in the carcinogenesis of human cutaneous squamous cell carcinoma (SCC). In 35 human cutaneous SCC samples, 86% showed overexpression of phosphorylated (p)-Stat3, and most of those simultaneously overexpressed p-EGFR or p-Akt. Constitutive activation of EGFR and Stat3 was observed in three SCC cell lines and four of five SCC tissues. AG1478, an inhibitor of the EGFR, downregulated Stat3 activation in HSC-1 human SCC cells. AG1478 inhibited cell proliferation and induced apoptosis of HSC-1 cells but did not inhibit the growth of normal human epidermal keratinocytes that did not show Stat3 activation. Furthermore, a PI3K inhibitor also suppressed Stat3 activation in HSC-1 cells to some degree. Combined treatment with the PI3K inhibitor and AG1478 strongly suppressed Stat3 activity and dramatically induced apoptosis of HSC-1 cells. These data suggest that Stat3 activation through EGFR and/or PI3K/Akt activation plays a critical role in the proliferation and survival of human cutaneous SCC.
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Rho O, Kim DJ, Kiguchi K, Digiovanni J. Growth factor signaling pathways as targets for prevention of epithelial carcinogenesis. Mol Carcinog 2010; 50:264-79. [PMID: 20648549 DOI: 10.1002/mc.20665] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2010] [Revised: 06/09/2010] [Accepted: 06/10/2010] [Indexed: 10/24/2022]
Abstract
Growth factor receptor (GFR) signaling controls epithelial cell growth by responding to various endogenous or exogenous stimuli and subsequently activating downstream signaling pathways including Stat3, PI3K/Akt/mTOR, MAPK, and c-Src. Environmental chemical toxicants and UVB irradiation cause enhanced and prolonged activation of GFR signaling and downstream pathways that contributes to epithelial cancer development including skin cancer. Recent studies, especially those with tissue-specific transgenic mouse models, have demonstrated that GFRs and their downstream signaling pathways contribute to all three stages of epithelial carcinogenesis by regulating a wide variety of biological functions including proliferation, apoptosis, angiogenesis, cell adhesion, and migration. Inhibiting these signaling pathways early in the carcinogenic process results in reduced cell proliferation and survival, leading to decreased tumor formation. Collectively, these studies suggest that GFR signaling and subsequent downstream signaling pathways are potential targets for the prevention of epithelial cancers including skin cancer.
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Affiliation(s)
- Okkyung Rho
- Division of Pharmacology & Toxicology, College of Pharmacy, The University of Texas at Austin, Austin, Texas 78723-3092, USA
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Sobti RC, Singh N, Hussain S, Suri V, Bharti AC, Das BC. Overexpression of STAT3 in HPV-mediated cervical cancer in a north Indian population. Mol Cell Biochem 2009; 330:193-9. [PMID: 19421717 DOI: 10.1007/s11010-009-0133-2] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2009] [Accepted: 04/16/2009] [Indexed: 12/31/2022]
Abstract
The constitutively activated STAT family members, particularly STAT3, have been shown to possess transforming properties, and are strongly correlated with tumor development and progression. STAT3 transmits signals from many cytokines and growth factors to target genes in the nucleus through the Jak/Stat signaling pathway. HPV is the main etiological factor in the development of cervical cancer. In the current study, the expression of STAT3 was analyzed in various stages of HPV-mediated cervical carcinogenesis. Tissue biopsies from 100 patients with cervical cancer of different stages and normal tissues from patients undergoing hysterectomy were selected for studying the HPV status and STAT3 expression. HPV status of each corresponding biopsy was analyzed by PCR and typing. The mRNA expression was analyzed by reverse-transcriptase polymerase chain reaction (RT-PCR). HPV infection was detected in majority of cases: 75% (9/12) in precancer, 85% (34/40) stage I & II, and 95% (36/38) in stage III & IV of cervical cancer cases by L1 PCR. Further sub typing revealed HPV16 in 100% (9/9) of L1 positives in precancerous & 90% (63/70) in different stages of cancer. Significant level of STAT3 mRNA expression was predominantly found in cervical cancer cases as compared to normal controls (P = 0.001). We also found a significant correlation of STAT3 expression in cases infected with HPV (P = 0.001). Our results indicate a potentially interactive effect between HPV 16/18 and transcriptional activation of STAT3 gene in cervical carcinogenesis. To our knowledge, this is the first such study to be reported from India. Further investigations are needed to determine the influence of STAT3 expression on cervical carcinogenesis and its possible interaction with HPV infection status.
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Affiliation(s)
- R C Sobti
- Department of Biotechnology, Panjab University, Chandigarh, 160014, India.
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Cai D, Cao J, Li Z, Zheng X, Yao Y, Li W, Yuan Z. Up-regulation of bone marrow stromal protein 2 (BST2) in breast cancer with bone metastasis. BMC Cancer 2009; 9:102. [PMID: 19338666 PMCID: PMC2674058 DOI: 10.1186/1471-2407-9-102] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2008] [Accepted: 04/01/2009] [Indexed: 11/15/2022] Open
Abstract
Background Bone metastases are frequent complications of breast cancer. Recent literature implicates multiple chemokines in the formation of bone metastases in breast cancer. However, the molecular mechanism of metastatic bone disease in breast cancer remains unknown. We have recently made the novel observation of the BST2 protein expression in human breast cancer cell lines. The purpose of our present study is to investigate the expression and the role of BST2 in bone metastatic breast cancer. Methods cDNA microarray analysis was used to compare the BST2 gene expression between a metastatic to bone human breast cancer cell line (MDA-231BO) and a primary human breast cancer cell line (MDA-231). The BST2 expression in one bone metastatic breast cancer and seven non-bone metastatic breast cancer cell lines were also determined using real-time RT-PCR and Western blot assays. We then employed tissue array to further study the BST2 expression in human breast cancer using array slides containing 20 independent breast cancer tumors that formed metastatic bone lesions, 30 non-metastasis-forming breast cancer tumors, and 8 normal breast tissues. In order to test the feasibility of utilizing BST2 as a serum marker for the presence of bone metastasis in breast cancer, we had measured the BST2 expression levels in human serums by using ELISA on 43 breast cancer patients with bone metastasis, 43 breast cancer patients without bone metastasis, and 14 normal healthy controls. The relationship between cell migration and proliferation and BST2 expression was also studied in a human breast recombinant model system using migration and FACS analysis. Results The microarray demonstrated over expression of the BST2 gene in the bone metastatic breast cancer cell line (MDA-231BO) compared to the primary human breast cancer cell line (MDA-231). The expression of the BST2 gene was significantly increased in the bone metastatic breast cancer cell lines and tumor tissues compared to non-bone metastatic breast cancer cell lines and tumor tissues by real time RT-PCR, Western blot and TMA. Furthermore, serum levels of BST2 measured by ELISA were also significantly higher among patients with breast cancer metastatic to bone compared to breast cancer patients without metastatic to bone (P < .0001). Most importantly, the breast cancer cell line that transfected with BST2 demonstrated increased BST2 expressions, which was associated with increased cancer cell migration and cell proliferation. Conclusion These results provide novel data indicating the BST2 protein expression is associated with the formation of bone metastases in human breast cancer. We believe that BST2 may be a potential biomarker in breast cancer with bone metastasis.
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Affiliation(s)
- Dongqing Cai
- Key Laboratory for Regenerative Medicine of Ministry of Education, Ji Nan University, Guangzhou, PR China.
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Kim BH, Yin CH, Guo Q, Bach EA, Lee H, Sandoval C, Jayabose S, Ulaczyk-Lesanko A, Hall DG, Baeg GH. A small-molecule compound identified through a cell-based screening inhibits JAK/STAT pathway signaling in human cancer cells. Mol Cancer Ther 2008; 7:2672-80. [PMID: 18790749 DOI: 10.1158/1535-7163.mct-08-0309] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Inappropriate activation of JAK/STAT signaling occurs with high frequency in human cancers and is associated with cancer cell survival and proliferation. Therefore, the development of pharmacologic STAT signaling inhibitors has therapeutic potential in the treatment of human cancers. Here, we report 2-[(3,5-bis-trifluoromethyl-phenyl)-hydroxy-methyl]-1-(4-nitro-phenylamino)-6-phenyl-1,2,4a,7a-tetrahydro-pyrrolo[3,4-b]-pyridine-5,7-dione (AUH-6-96) as a novel small-molecule inhibitor of JAK/STAT signaling that we initially identified through a cell-based high-throughput screening using cultured Drosophila cells. Treatment of Drosophila cells with AUH-6-96 resulted in a reduction of Unpaired-induced transcriptional activity and tyrosine phosphorylation of STAT92E, the sole Drosophila STAT homologue. In human cancer cell lines, AUH-6-96 inhibited both constitutive and interleukin-6-induced STAT3 phosphorylation. Specifically, in Hodgkin lymphoma L540 cells, treatment with AUH-6-96 resulted in reduced levels of tyrosine phosphorylated STAT3 and of the STAT3 downstream target gene SOCS3 in a dose- and time-dependent manner. In addition, AUH-6-96-treated L540 cells showed decreased expression of persistently activated JAK3, suggesting that AUH-6-96 inhibits the JAK/STAT pathway signaling in L540 cells by affecting JAK3 activity and subsequently blocking STAT3 signaling. Importantly, AUH-6-96 selectively affected cell viability only of cancer cells harboring aberrant JAK/STAT signaling. In support of the specificity of AUH-6-96 for inhibition of JAK/STAT signaling, treatment with AUH-6-96 decreased cancer cell survival by inducing programmed cell death by down-regulating the expression of STAT3 downstream target antiapoptotic genes, such as Bcl-xL. In summary, this study shows that AUH-6-96 is a novel small-molecule inhibitor of JAK/STAT signaling and may have therapeutic potential in the treatment of human cancers harboring aberrant JAK/STAT signaling.
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Affiliation(s)
- Byung Hak Kim
- Department of Pediatrics, Division of Hematology/Oncology, New York Medical College, Valhalla, NY 10595, USA
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Chau MN, Banerjee PP. Development of a STAT3 reporter prostate cancer cell line for high throughput screening of STAT3 activators and inhibitors. Biochem Biophys Res Commun 2008; 377:627-631. [PMID: 18930029 DOI: 10.1016/j.bbrc.2008.10.025] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2008] [Accepted: 10/07/2008] [Indexed: 01/30/2023]
Abstract
STAT3 is constitutively activated in several cancers, including prostate cancer, and is therefore, a potential target for cancer therapy. DU-145 prostate cancer cells were stably co-transfected with STAT3 reporter and puromycin resistant plasmids to create a stable STAT3 reporter cell line that can be used for high throughput screening of STAT3 modulators. The applicability of this cell line was tested with two known activators and inhibitors of STAT3. As expected, EGF and IL-6 increased STAT3 reporter activity and enhanced the nuclear localization of phosphorylated STAT3 (pSTAT3); whereas Cucurbitacin I and AG490 decreased STAT3 reporter activity dose and time-dependently and reduced the localization of pSTAT3 in the nuclei of prostate cancer cells. Given the importance of STAT3 in cancer initiation and progression, the development of a stable STAT3 reporter cell line in prostate cancer cells provides a rapid, sensitive, and cost effective method for the screening of potential STAT3 modulators.
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Affiliation(s)
- My N Chau
- Department of Biochemistry, Molecular and Cellular Biology, Georgetown University Medical Center, Medical-Dental Building, Room C406B, 3900 Reservoir Road, Northwest, Washington, DC 20057, USA
| | - Partha P Banerjee
- Department of Biochemistry, Molecular and Cellular Biology, Georgetown University Medical Center, Medical-Dental Building, Room C406B, 3900 Reservoir Road, Northwest, Washington, DC 20057, USA.
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Berishaj M, Gao SP, Ahmed S, Leslie K, Al-Ahmadie H, Gerald WL, Bornmann W, Bromberg JF. Stat3 is tyrosine-phosphorylated through the interleukin-6/glycoprotein 130/Janus kinase pathway in breast cancer. Breast Cancer Res 2007; 9:R32. [PMID: 17531096 PMCID: PMC1929096 DOI: 10.1186/bcr1680] [Citation(s) in RCA: 195] [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: 03/29/2007] [Revised: 04/21/2007] [Accepted: 05/25/2007] [Indexed: 01/02/2023] Open
Abstract
Introduction Signal transducer and activator of transcription 3 (Stat3) is constitutively tyrosine-phosphorylated in approximately 50% of primary breast carcinomas. A number of different mechanisms responsible for Stat3 activation, including abnormal activation of receptor tyrosine kinases, Src, and Janus kinases (Jaks), have been implicated in breast cancer. Methods We examined six breast cancer-derived cell lines expressing high or low levels of tyrosine-phosphorylated Stat3 (pStat3) as well as primary breast cancer specimens. Results Inhibition of Src or EGFR (epidermal growth factor receptor) tyrosine kinases had no effect on pStat3 levels, whereas pan-Jak inhibitor P6 resulted in complete abrogation of Stat3 phosphorylation and inhibition of growth. Jaks are required for cytokine signaling, and the glycoprotein 130 (gp130) receptor-associated Jaks are known mediators of Stat3 phosphorylation. Blockade of the gp130 receptor or sequestration of the interleukin-6 (IL-6) ligand led to a decrease of pStat3 levels. Conditioned media from those cell lines expressing high levels of pStat3 contained IL-6 and were capable of stimulating Stat3 phosphorylation. We examined IL-6 levels in primary breast tumors and found a positive correlation between pStat3 and IL-6 expression. Conclusion In summary, a principal mechanism of Stat3 activation in breast cancer is through the IL-6/gp130/Jak pathway.
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Affiliation(s)
- Marjan Berishaj
- Department of Medicine, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10021 USA
| | - Sizhi Paul Gao
- Department of Medicine, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10021 USA
| | - Simi Ahmed
- Laboratory of Molecular Cell Biology, 1230 York Avenue, Rockefeller University, New York, NY, 10021 USA
| | - Kenneth Leslie
- Department of Medicine, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10021 USA
| | - Hikmat Al-Ahmadie
- Department of Pathology, 1275 York Avenue, Memorial Sloan-Kettering Cancer Center, New York, NY 10021 USA
| | - William L Gerald
- Department of Pathology, 1275 York Avenue, Memorial Sloan-Kettering Cancer Center, New York, NY 10021 USA
| | - William Bornmann
- Division of Experimental Diagnostic Imaging, 1515 Holcombe Blvd., University of Texas M. D. Anderson Cancer Center, Houston, TX 77030 USA
| | - Jacqueline F Bromberg
- Department of Medicine, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10021 USA
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Petterino C, Podestà G, Ratto A, Drigo M, Pellegrino C. Immunohistochemical study of phospho-Stat3-ser727 expression in feline mammary gland tumours. Vet Res Commun 2006; 31:173-84. [PMID: 17186410 DOI: 10.1007/s11259-006-3330-4] [Citation(s) in RCA: 6] [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] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/14/2005] [Indexed: 11/28/2022]
Abstract
We describe the expression of pStat3-ser727 (signal transducer and activator of transcription 3 phosphorylated on serine 727) in normal, hyperplastic and neoplastic feline mammary gland tissue assessed by immunohistochemistry in 56 cats. The samples included 4 normal mammary non-lactating tissues, 13 hyperplastic lesions (9 lobular and 4 fibroepithelial) and 39 tumours (6 benign and 33 carcinomas). For immunohistochemistry, tissue sections were incubated with anti-pStat3-ser727 monoclonal antibodies and visualized with EnVision-DAB polymer. pStat3-ser727 positivity was quantified in a semi-quantitative manner, differentiating cytoplasmic and nuclear localization. Intense anti-pStat3-ser727 immunoreactivity was detected in epithelial neoplastic cells and in the fibro-component in two fibroepithelial hyperplastic lesions. The immunostaining was dot-like in the cytoplasm and homogeneous in the nuclei in both benign and malignant lesions. Statistically significant relations were observed between nuclear expression of pStat3-ser727 and the pleomorphism score (p = 0.006), mitotic activity (p < 0.0001), and histological grade (p < 0.0001). In contrast, no significant correlations were observed for cytoplasmic pStat3-ser727. These findings add new and interesting information on the potential role of the phosphorylated form of Stat3 in malignant lesions.
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Affiliation(s)
- C Petterino
- Department of Public Health, Comparative Pathology and Veterinary Hygiene School of Veterinary Medicine, University of Padua, Agripolis, Legnaro.
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Buettner M, Heussinger N, Niedobitek G. Expression of Epstein-Barr virus (EBV)-encoded latent membrane proteins and STAT3 activation in nasopharyngeal carcinoma. Virchows Arch 2006; 449:513-9. [PMID: 17033798 DOI: 10.1007/s00428-006-0294-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [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: 07/03/2006] [Accepted: 08/07/2006] [Indexed: 10/24/2022]
Abstract
The Epstein-Barr virus (EBV) is associated with virtually all cases of undifferentiated nasopharyngeal carcinoma (NPC), and it was proposed that the EBV-encoded transforming protein, latent membrane protein (LMP) 1, may play a role in the neoplastic process. It was proposed recently that LMP1 expression in epithelial cells may be regulated through a loop involving activated signal transducer and activator of transcription 3 (STAT3), LMP1, LMP1-mediated induction of interleukin (IL)-6 expression and STAT3 activation through the IL-6 receptor. This autoregulatory loop may be suppressed by another viral protein, LMP2A, an effect which in turn can be overcome by exogenous IL-6. Here we show that, as expected, expression of LMP1 and LMP2A tend to be exclusive in NPC tumours. Rare cases showing a co-expression of both proteins can be explained by STAT3 activation via the receptors for IL-6 or epidermal growth factor. STAT3 activation was a consistent feature of NPC tumour cells. However, in most cases, this was not accompanied by detectable expression of LMP1, suggesting either that LMP2A expression may suffice to suppress LMP1 expression or that additional factors may be operational. This study emphasises the need to correlate in vitro results with observational studies of ex vivo tumour tissues.
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Affiliation(s)
- Maike Buettner
- Pathologisches Institut, Friedrich-Alexander-Universität, Krankenhausstr. 8-10, 91054 Erlangen, Germany.
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Dien J, Amin HM, Chiu N, Wong W, Frantz C, Chiu B, Mackey JR, Lai R. Signal transducers and activators of transcription-3 up-regulates tissue inhibitor of metalloproteinase-1 expression and decreases invasiveness of breast cancer. Am J Pathol 2006; 169:633-42. [PMID: 16877361 PMCID: PMC1698804 DOI: 10.2353/ajpath.2006.051109] [Citation(s) in RCA: 36] [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] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Signal transducers and activators of transcription (STAT)-3 is an oncogenic protein that is constitutively activated in many human cancers, including 30 to 60% of primary breast cancer. The biological significance of STAT3 activation in breast cancer is not fully understood. We have previously shown that STAT3 up-regulates tissue inhibitors of metalloproteinase (TIMP)-1, a cytokine known to block metalloproteinases and decrease invasiveness in certain cancer cell types. We hypothesize that STAT3 activation may modulate tumor invasiveness of breast cancer by regulating TIMP1 expression. Using MCF-7 cells transfected with tetracycline-off STAT3C (constitutively active STAT3), we generated an in vitro system in which STAT3C levels can be tightly controlled in breast cancer cells. Increasing tetracycline levels gradually decreased STAT3C and TIMP1 in a dose-dependent manner, and down-regulation of these proteins led to a reciprocal decrease in invasiveness of these cells in Matrigel. Addition of a neutralizing anti-TIMP1 antibody increased invasiveness in the same experimental system. Using immunohistochemistry and 142 primary breast tumors, we found a significant association between the expression of the phosphorylated/active form of STAT3 (pSTAT3) and that of TIMP1. Importantly, STAT3 activation correlated significantly with a lower frequency of vascular and lymphatic invasion (P = 0.015 and P = 0.0002, respectively). Our data support the concept that STAT3 activation significantly modulates the biological and clinical behavior of breast cancer.
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Affiliation(s)
- Jennifer Dien
- Department of Laboratory Medicine and Pathology, University of Alberta, 4B1, 8440 112 St., Edmonton, Alberta, Canada
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Yang SF, Wang SN, Wu CF, Yeh YT, Chai CY, Chunag SC, Sheen MC, Lee KT. Altered p-STAT3 (tyr705) expression is associated with histological grading and intratumour microvessel density in hepatocellular carcinoma. J Clin Pathol 2006; 60:642-8. [PMID: 16901975 PMCID: PMC1955084 DOI: 10.1136/jcp.2006.036970] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
BACKGROUND Constitutive activation of signal transducer and activator of transcription 3 at tyrosine residue 705 (p-STAT3 (tyr705)) has been associated with many types of human cancers. However, its potential roles and biological effects in hepatocellular carcinoma (HCC) are not well established. AIM To explore whether an altered p-STAT3 (tyr705) expression is associated with angiogenesis or proliferation and thereby plays a part in HCC development. METHODS Paraffin-wax-embedded sections from 69 patients with HCC were collected in this study. Using a semiquantitative immunohistochemical staining method, the expression patterns of p-STAT3 (tyr705) in both HCC lesions and the adjacent non-tumorous liver parenchyma were analysed. The results obtained were further correlated with intratumour microvessel density (MVD), Ki-67 expression, clinicopathological parameters and overall survival. RESULTS A strong p-STAT3 (tyr705) nuclear staining was observed in 49.3% of HCC lesions, but was reported only in 5.8% of the adjacent non-tumorous liver parenchyma (p<0.001). The expression of p-STAT3 (tyr705) in HCC lesions was significantly and positively correlated with the intratumour MVD (p = 0.002), but not with Ki-67 expression. No significant correlation of p-STAT3 (tyr705) was found in addition to histological grading (p = 0.019). Multivariate Cox regression analysis showed that p-STAT3 (tyr705) expression was a significant predictor of overall survival for HCC (p = 0.036), although the Kaplan-Meier survival curves showed no significant difference between the high and low p-STAT3 (tyr705) expression subgroups. CONCLUSIONS The results showed that p-STAT3 (tyr705) expression was closely correlated with histological grading and intratumour MVD in HCC. Thus, the potential role of p-STAT3 (tyr705) in HCC development may be through these correlations.
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Affiliation(s)
- Sheau-Fang Yang
- Department of Pathology, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
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Yang SF, Wang SN, Wu CF, Yeh YT, Chai CY, Chunag SC, Sheen MC, Lee KT. Altered p-STAT3 (tyr705) expression is associated with histological grading and intratumour microvessel density in hepatocellular carcinoma. J Clin Pathol. 2007;60:642-648. [PMID: 16901975 DOI: 10.1136/jcp.2006.036970.] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
BACKGROUND Constitutive activation of signal transducer and activator of transcription 3 at tyrosine residue 705 (p-STAT3 (tyr705)) has been associated with many types of human cancers. However, its potential roles and biological effects in hepatocellular carcinoma (HCC) are not well established. AIM To explore whether an altered p-STAT3 (tyr705) expression is associated with angiogenesis or proliferation and thereby plays a part in HCC development. METHODS Paraffin-wax-embedded sections from 69 patients with HCC were collected in this study. Using a semiquantitative immunohistochemical staining method, the expression patterns of p-STAT3 (tyr705) in both HCC lesions and the adjacent non-tumorous liver parenchyma were analysed. The results obtained were further correlated with intratumour microvessel density (MVD), Ki-67 expression, clinicopathological parameters and overall survival. RESULTS A strong p-STAT3 (tyr705) nuclear staining was observed in 49.3% of HCC lesions, but was reported only in 5.8% of the adjacent non-tumorous liver parenchyma (p<0.001). The expression of p-STAT3 (tyr705) in HCC lesions was significantly and positively correlated with the intratumour MVD (p = 0.002), but not with Ki-67 expression. No significant correlation of p-STAT3 (tyr705) was found in addition to histological grading (p = 0.019). Multivariate Cox regression analysis showed that p-STAT3 (tyr705) expression was a significant predictor of overall survival for HCC (p = 0.036), although the Kaplan-Meier survival curves showed no significant difference between the high and low p-STAT3 (tyr705) expression subgroups. CONCLUSIONS The results showed that p-STAT3 (tyr705) expression was closely correlated with histological grading and intratumour MVD in HCC. Thus, the potential role of p-STAT3 (tyr705) in HCC development may be through these correlations.
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Abstract
Growth factor-induced migration is a rate-limiting step in tumour invasiveness. The molecules that regulate this cellular behaviour would represent novel targets for limiting tumour cell progression. Epidermal growth factor (EGF) receptor (EGFR)-mediated motility, present in both autocrine and paracrine modes in prostate carcinomas, requires de novo transcription to persist over times greater than a few hours. Therefore, we sought to define specific signalling pathways that directly alter cellular transcription. Signal transducer and activator of transcription 3 (STAT3) is activated, as determined by electrophoretic motility shift assays, by EGFR in DU145 and PC3 human prostate carcinoma cells in addition to the motility model NR6 fibroblast cell line. Inhibition of STAT3 activity by antisense or siRNA downregulation or expression of a dominant-negative construct limited cell motility as determined by an in vitro wound healing assay and invasiveness through a extracellular matrix barrier. The expression of constitutively activated STAT3 did not increase the migration, which indicates that STAT3 is necessary but not sufficient for EGFR-mediated migration. These findings suggest that STAT3 signalling may be a new target for limiting prostate tumour cell invasion. In a microarray gene analysis of what transcription units are altered by EGF in a STAT3-dependent manner we found that the expression of motility-limiting VASP protein and the apoptosis nexus caspase 3 were both downregulated upon EGF exposure. These findings suggest a molecular basis for the STAT3 dependence of EGFR-mediated prostate tumour progression.
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Affiliation(s)
- W Zhou
- Laboratory and Pathology Service, Pittsburgh VAMC, PA, USA
| | - J R Grandis
- Department of Pathology, University of Pittsburgh, Scaife Hall, S-713, 3550 Terrace St, Pittsburgh, PA 15261, USA
- Department of Otolaryngology, University of Pittsburgh, Pittsburgh, PA 15261 USA
| | - A Wells
- Laboratory and Pathology Service, Pittsburgh VAMC, PA, USA
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Yin W, Cheepala S, Roberts JN, Syson-Chan K, DiGiovanni J, Clifford JL. Active Stat3 is required for survival of human squamous cell carcinoma cells in serum-free conditions. Mol Cancer 2006; 5:15. [PMID: 16603078 PMCID: PMC1502137 DOI: 10.1186/1476-4598-5-15] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.7] [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: 10/24/2005] [Accepted: 04/07/2006] [Indexed: 12/23/2022] Open
Abstract
Background Squamous cell carcinoma (SCC) of the skin is the most aggressive form of non-melanoma skin cancer (NMSC), and is the single most commonly diagnosed cancer in the U.S., with over one million new cases reported each year. Recent studies have revealed an oncogenic role of activated signal transducer and activator of transcription 3 (Stat3) in many human tumors, especially in those of epithelial origin, including skin SCC. Stat3 is a mediator of numerous growth factor and cytokine signaling pathways, all of which activate it through phosphorylation of tyrosine 705. Results To further address the role of Stat3 in skin SCC tumorigenesis, we have analyzed a panel of human skin-derived cell lines ranging from normal human epidermal keratinocytes (NHEK), to non-tumorigenic transformed skin cells (HaCaT), to highly tumorigenic cells (SRB1-m7 and SRB12-p9) and observed a positive correlation between Stat3 phosphorylation and SCC malignancy. We next determined the role of Stat3 activity in cell proliferation and viability under serum-free culture conditions. This was accomplished by suppressing Stat3 activity in the SRB12-p9 cells through stable expression of a dominant negative acting form of Stat3β, which contains a tyrosine 705 to phenylalanine mutation (S3DN). The S3DN cells behaved similar to parental SRB12-p9 cells when cultured in optimal growth conditions, in the presence of 10% fetal calf serum. However, unlike the SRB12-p9 cells, S3DN cells underwent apoptotic cell death when cultured in serum-free medium (SFM). This was evidenced by multiple criteria, including accumulation of sub-G1 particles, induced PARP cleavage, and acquisition of the characteristic morphological changes associated with apoptosis. Conclusion This study provides direct evidence for a role for Stat3 in maintaining cell survival in the conditions of exogenous growth factor deprivation produced by culture in SFM. We also propose that delivery of the S3DN gene or protein to tumor cells could induce apoptosis and/or sensitize those cells to the apoptotic effects of cancer therapeutic agents, raising the possibility of using S3DN as an adjunct for treatment of skin SCC.
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Affiliation(s)
- Weihong Yin
- Department of Biochemistry and Molecular Biology, Louisiana State University Health Science Center School of Medicine in Shreveport and Feist-Weiller Cancer Center, Shreveport, LA 71130, USA
| | - Satish Cheepala
- Department of Biochemistry and Molecular Biology, Louisiana State University Health Science Center School of Medicine in Shreveport and Feist-Weiller Cancer Center, Shreveport, LA 71130, USA
| | - Jennifer N Roberts
- Department of Biochemistry and Molecular Biology, Louisiana State University Health Science Center School of Medicine in Shreveport and Feist-Weiller Cancer Center, Shreveport, LA 71130, USA
| | - Keith Syson-Chan
- Department of Carcinogenesis, University of Texas-M.D. Anderson Cancer Center, Science Park Research Division, PO Box 389, Smithville, TX 78957, USA
| | - John DiGiovanni
- Department of Carcinogenesis, University of Texas-M.D. Anderson Cancer Center, Science Park Research Division, PO Box 389, Smithville, TX 78957, USA
| | - John L Clifford
- Department of Biochemistry and Molecular Biology, Louisiana State University Health Science Center School of Medicine in Shreveport and Feist-Weiller Cancer Center, Shreveport, LA 71130, USA
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Tan M, Lan KH, Yao J, Lu CH, Sun M, Neal CL, Lu J, Yu D. Selective Inhibition of ErbB2-Overexpressing Breast Cancer In vivo by a Novel TAT-Based ErbB2-Targeting Signal Transducers and Activators of Transcription 3–Blocking Peptide. Cancer Res 2006; 66:3764-72. [PMID: 16585203 DOI: 10.1158/0008-5472.can-05-2747] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.7] [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] [Indexed: 11/16/2022]
Abstract
ErbB2 is an excellent target for cancer therapies. Unfortunately, the outcome of current therapies for ErbB2-positive breast cancers remains unsatisfying due to resistance and side effects. New therapies for ErbB2-overexpressing breast cancers continue to be in great need. Peptide therapy using cell-penetrating peptides (CPP) as peptide carriers is promising because the internalization is highly efficient, and the cargoes delivered can be bioactive. However, the major obstacle in using these powerful CPPs for therapy is their lack of specificity. Here, we sought to develop a peptide carrier that could introduce therapeutics specifically to ErbB2-overexpressing breast cancer cells. By modifying the HIV TAT-derived CPP and conjugating anti-HER-2/neu peptide mimetic (AHNP), we developed the peptide carrier (P3-AHNP) that specifically targeted ErbB2-overexpressing breast cancer cells in vitro and in vivo. A signal transducers and activators of transcription 3 (STAT3)-inhibiting peptide conjugated to this peptide carrier (P3-AHNP-STAT3BP) was delivered more efficiently into ErbB2-overexpressing than ErbB2 low-expressing cancer cells in vitro and successfully decreased STAT3 binding to STAT3-interacting DNA sequence. P3-AHNP-STAT3BP inhibited cell growth in vitro, with ErbB2-overexpressing 435.eB breast cancer cells being more sensitive to the treatment than the ErbB2 low-expressing MDA-MB-435 cells. Compared with ErbB2 low-expressing MDA-MB-435 xenografts, i.p. injected P3-AHNP-STAT3BP preferentially accumulated in 435.eB xenografts, which led to more reduction of proliferation and increased apoptosis and targeted inhibition of tumor growth. This novel peptide delivery system provided a sound basis for the future development of safe and effective new-generation therapeutics to cancer-specific molecular targets.
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Affiliation(s)
- Ming Tan
- Departments of Surgical Oncology and Molecular and Cellular Oncology, The University of Texas M.D. Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030, USA
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Becker M, Sommer A, Krätzschmar JR, Seidel H, Pohlenz H, Fichtner I. Distinct gene expression patterns in a tamoxifen-sensitive human mammary carcinoma xenograft and its tamoxifen-resistant subline MaCa 3366/TAM. Mol Cancer Ther 2005; 4:151-170. [DOI: 10.1158/1535-7163.151.4.1] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
The reasons why human mammary tumors become resistant to tamoxifen therapy are mainly unknown. Changes in gene expression may occur as cells acquire resistance to antiestrogens. We therefore undertook a comparative gene expression analysis of tamoxifen-sensitive and tamoxifen-resistant human breast cancer in vivo models using Affymetrix oligonucleotide arrays to analyze differential gene expression. Total RNAs from the tamoxifen-sensitive patient-derived mammary carcinoma xenograft MaCa 3366 and the tamoxifen-resistant model MaCa 3366/TAM were hybridized to Affymetrix HuGeneFL and to Hu95Av2 arrays. Pairwise comparisons and clustering algorithms were applied to identify differentially expressed genes and patterns of gene expression. As revealed by cluster analysis, the tamoxifen-sensitive and the tamoxifen-resistant breast carcinomas differed regarding their gene expression pattern. More than 100 transcripts are changed in abundance in MaCa 3366/TAM as compared with MaCa 3366. Among the genes that are differentially expressed in the tamoxifen-resistant tumors, there are several IFN-inducible and estrogen-responsive genes, and genes known to be involved in breast carcinogenesis. The genes neuronatin (NNAT) and bone marrow stem cell antigen 2 (BST2) were sharply up-regulated in MaCa 3366/TAM. The differential expression of four genes (NNAT, BST2, IGFBP5, and BCAS1) was confirmed by Taqman PCR. Our results provide the starting point for deriving markers for tamoxifen resistance by differential gene expression profiling in a human breast cancer model of acquired tamoxifen resistance. Finally, genes whose expression profiles are distinctly changed between the two xenograft lines will be further evaluated as potential targets for diagnostic or therapeutic approaches of tamoxifen-resistant breast cancer.
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Abstract
Stats (for signal transducers and activators of transcription) are a family of transcription factors that regulate cell growth and differentiation. Their activity is latent until phosphorylation by receptor-associated kinases. A sizable body of data from cell lines, mouse models, and human tissues now implicates these transcription factors in the oncogenesis of breast cancer. Because Stat activity is modulated by several posttranslational modifications and protein-protein interactions, these transcription factors are capable of integrating inputs from multiple signaling networks. Given this, the future utilization of Stats as prognostic markers and therapeutic targets in human breast cancer appears likely.
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Affiliation(s)
- Charles V Clevenger
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, 513 SC Labs, 422 Curie Blvd., Philadelphia, PA 19104, USA.
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Andl CD, Mizushima T, Oyama K, Bowser M, Nakagawa H, Rustgi AK. EGFR-induced cell migration is mediated predominantly by the JAK-STAT pathway in primary esophageal keratinocytes. Am J Physiol Gastrointest Liver Physiol 2004; 287:G1227-37. [PMID: 15284024 DOI: 10.1152/ajpgi.00253.2004] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.4] [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: 01/31/2023]
Abstract
The epidermal growth factor receptor (EGFR) activates several signaling cascades in response to epidermal growth factor stimulation. One of these signaling events involves tyrosine phosphorylation of signal transducer and activator of transcription (STAT), whereas another involves activation of the phosphatidylinositol 3-OH kinase pathway. Two possibilities for STAT activation exist: a janus kinase (JAK)-dependent and a JAK-independent mechanism. Herein, we demonstrate that EGFR overexpression in primary esophageal keratinocytes activates STAT in a JAK-dependent fashion with the functional consequence of enhanced cell migration, which can be abolished by use of a JAK-specific inhibitor, AG-490. We determined the mechanisms underlying the signal transduction pathway responsible for increased cell migration. Stimulation of EGFR induces Tyr701 phosphorylation of STAT1 and initiates complex formation of STAT1 and STAT3 with JAK1 and JAK2. Thereafter, the STATs translocate to the nucleus within 15 min. In addition, we found that activation of this signaling pathway results in matrix metalloproteinase-1 (MMP-1) activity. By contrast, Akt activation does not impact the EGFR-STATs-JAKs complex formation and nuclear translocation of the STATs with subsequent MMP-1 activity, although Akt activation may contribute to cell migration through an independent mechanism. Taken together, we find that the recruitment of the STAT-JAK complex by EGFR is responsible for keratinocyte migration that, in turn, might be mediated by MMP-1 activation.
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Affiliation(s)
- Claudia D Andl
- Gastroenterology Division, Department of Medicine, Abramson Cancer Center and Family Cancer Research Institute, University of Pennsylvania, 415 Curie Blvd., Philadelphia, PA 19104, USA
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Chan KS, Carbajal S, Kiguchi K, Clifford J, Sano S, DiGiovanni J. Epidermal Growth Factor Receptor-Mediated Activation of Stat3 during Multistage Skin Carcinogenesis. Cancer Res 2004; 64:2382-9. [PMID: 15059889 DOI: 10.1158/0008-5472.can-03-3197] [Citation(s) in RCA: 140] [Impact Index Per Article: 7.0] [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] [Indexed: 02/02/2023]
Abstract
In the present study, we have investigated the possible role of signal transducers and activators of transcription (STATs), particularly Stat3, in mouse skin tumor promotion and multistage carcinogenesis. Stat1, Stat3, and Stat5 were activated in mouse epidermis after treatment with different classes of tumor promoters, including 12-O-tetradecanoylphorbol-13-acetate (TPA), okadaic acid, and chrysarobin. In addition, Stat1, Stat3, and Stat5 were constitutively activated in skin tumors generated by the two-stage carcinogenesis regimen using 7,12-dimethylbenz(a)anthracene as initiator and TPA as promoter. Several approaches were used to examine the possible role of epidermal growth factor receptor (EGFR) in modulating Stat3 activity during tumor promotion. In primary cultures of mouse keratinocytes, addition of exogenous EGF led to activation of Stat3 as shown by an elevation in tyrosine phosphorylation and nuclear translocation. In epidermis of transgenic mice expressing transforming growth factor alpha under control of the keratin 14 promoter, Stat3 was constitutively activated. Abrogation of EGFR function in mouse epidermis using an EGFR kinase inhibitor or by overexpressing a dominant negative form of EGFR led to a reduction in Stat3 activation in response to TPA treatment. Immunoprecipitation analyses using lysates from TPA-treated epidermis and skin papillomas showed enhanced interaction between the EGFR and Stat3. Finally, Stat3 deficiency in mouse epidermis significantly reduced the proliferative response after TPA treatment. Collectively, the current results suggest that Stat3 activation may be a critical event during mouse skin tumor promotion, possibly through regulation of keratinocyte proliferation. In addition, Stat3 activation in tumor promoter-treated epidermis and in skin papillomas may occur, at least in part, via interaction with and phosphorylation by the EGFR. Finally, constitutive activation of Stat3 in both papillomas and squamous cell carcinomas suggest a role in both the development of autonomous growth and the progression of epithelial tumors in mouse skin.
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Affiliation(s)
- Keith Syson Chan
- Department of Carcinogenesis, The University of Texas, M. D. Anderson Cancer Center, Science Park-Research Division, Smithville, Texas 78957, USA
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Abstract
Transformation of breast cells occurs through loss or mutation of tumor suppressor genes, or activation or amplification of oncogenes, leading to deregulation of signal transduction pathways, abnormal amplification of growth signals, and aberrant expression of genes that ultimately transform the cells into invasive cancer. The goal of cancer preventive therapy, or "chemoprevention," is to eliminate premalignant cells or to block the progression of normal cells into cancer. Multiple alterations in signal pathways and transcription factors are observed in mammary gland tumorigenesis. In particular, estrogen receptor (ER) deregulation plays a critical role in breast cancer development and progress, and targeting ER with selective ER modulators (SERMs) has achieved significant reduction of breast cancer incidence in women at high risk for breast cancer. However, not all breast cancer is prevented by SERMs, because 30-40% of the tumors are ER-negative. Other receptors for retinoids, vitamin D analogs and peroxisome proliferator-activiator, along with transcription factors such as AP-1, NF-kappaB, and STATs (signal transducers and activators of transcription) affect breast tumorigenesis. This is also true for the signal transduction pathways, for example cyclooxygenase 2 (Cox-2), HER2/neu, mitogen-activated protein kinase (MAPK), and PI3K/Akt. Therefore, proteins in pathways that are altered during the process of mammary tumorigenesis may be promising targets of future chemopreventive drugs. Many newly-developed synthetic or natural compounds/agents are now under testing in preclinical studies and clinical trials. Receptor selective retinoids, receptor tyrosine kinase inhibitors (TKIs), SERMs, Cox-2 inhibitors, and others are some of the promising novel agents for the prevention of breast cancer. The chemopreventive activity of these agents and other novel signal transduction inhibitors are discussed in this chapter.
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Affiliation(s)
- Qiang Shen
- Breast Center, Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas, USA
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