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Wulansari N, Sulistio YA, Darsono WHW, Kim CH, Lee SH. LIF maintains mouse embryonic stem cells pluripotency by modulating TET1 and JMJD2 activity in a JAK2-dependent manner. STEM CELLS (DAYTON, OHIO) 2021; 39:750-760. [PMID: 33529470 DOI: 10.1002/stem.3345] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 01/08/2021] [Indexed: 11/09/2022]
Abstract
The LIF-JAK2-STAT3 pathway is the central signal transducer that maintains undifferentiated mouse embryonic stem cells (mESCs), which is achieved by the recruitment of activated STAT3 to the master pluripotency genes and activation of the gene transcriptions. It remains unclear, however, how the epigenetic status required for the master gene transcriptions is built into LIF-treated mESC cultures. In this study, Jak2, but not Stat3, in the LIF canonical pathway, establishes an open epigenetic status in the pluripotency gene promoter regions. Upon LIF activation, cytosolic JAK2 was translocalized into the nucleus of mESCs, and reduced DNA methylation (5mC levels) along with increasing DNA hydroxymethylation (5hmC) in the pluripotent gene (Nanog/Pou5f1) promoter regions. In addition, the repressive histone codes H3K9m3/H3K27m3 were reduced by JAK2. Activated JAK2 directly interacted with the core epigenetic enzymes TET1 and JMJD2, modulating its activity and promotes the DNA and histone demethylation, respectively. The JAK2 effects were attained by tyrosine phosphorylation on the epigenetic enzymes. The effects of JAK2 phosphorylation on the enzymes were diverse, but all were merged to the epigenetic signatures associated with open DNA/chromatin structures. Taken together, these results reveal a previously unrecognized epigenetic regulatory role of JAK2 as an important mediator of mESC maintenance.
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Affiliation(s)
- Noviana Wulansari
- Department of Biochemistry and Molecular Biology, College of Medicine, Hanyang University, Seoul, South Korea.,Hanyang Biomedical Research Institute, Hanyang University, Seoul, South Korea
| | - Yanuar Alan Sulistio
- Department of Biochemistry and Molecular Biology, College of Medicine, Hanyang University, Seoul, South Korea.,Hanyang Biomedical Research Institute, Hanyang University, Seoul, South Korea
| | - Wahyu Handoko Wibowo Darsono
- Department of Biochemistry and Molecular Biology, College of Medicine, Hanyang University, Seoul, South Korea.,Hanyang Biomedical Research Institute, Hanyang University, Seoul, South Korea.,Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul, South Korea
| | - Chang-Hoon Kim
- Hanyang Biomedical Research Institute, Hanyang University, Seoul, South Korea
| | - Sang-Hun Lee
- Department of Biochemistry and Molecular Biology, College of Medicine, Hanyang University, Seoul, South Korea.,Hanyang Biomedical Research Institute, Hanyang University, Seoul, South Korea.,Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul, South Korea
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Zhou B, Jin X, Jin W, Huang X, Wu Y, Li H, Zhu W, Qin X, Ye H, Gao S. WT1 facilitates the self-renewal of leukemia-initiating cells through the upregulation of BCL2L2: WT1-BCL2L2 axis as a new acute myeloid leukemia therapy target. J Transl Med 2020; 18:254. [PMID: 32580769 PMCID: PMC7313134 DOI: 10.1186/s12967-020-02384-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Accepted: 05/21/2020] [Indexed: 12/24/2022] Open
Abstract
Background Overexpression of Wilms’ tumor-1 (WT1) transcription factor facilitates proliferation in acute myeloid leukemia (AML). However, whether WT1 is enriched in the leukemia-initiating cells (LICs) and leukemia stem cells (LSCs) and facilitates the self-renewal of LSCs remains poorly understood. Methods MLL-AF9-induced murine leukemia model was used to evaluate the effect of knockdown of wt1 on the self-renewal ability of LSC. RNA sequencing was performed on WT1-overexpressing cells to select WT1 targets. Apoptosis and colony formation assays were used to assess the anti-leukemic potential of a deubiquitinase inhibitor WP1130. Furthermore, NOD/SCID-IL2Rγ (NSG) AML xenotransplantation and MLL-AF9-induced murine leukemia models were used to evaluate the anti-leukemogenic potential of WP1130 in vivo. Results We found that wt1 is highly expressed in LICs and LSCs and facilitates the maintenance of leukemia in a murine MLL-AF9-induced model of AML. WT1 enhanced the self-renewal of LSC by increasing the expression of BCL2L2, a member of B cell lymphoma 2 (BCL2) family, by direct binding to its promoter region. Loss of WT1 impaired self-renewal ability in LSC and delayed the progression of leukemia. WP1130 was found to modify the WT1-BCL2L2 axis, and WP1130-induced anti-leukemic activity was mediated by ubiquitin proteasome-mediated destruction of WT1 protein. WP1130 induced apoptosis and decreased colony formation abilities of leukemia cells and prolonged the overall survival in the THP1-based xenograft NSG mouse model. WP1130 also decreased the frequency of LSC and prolonged the overall survival in MLL-AF9-induced murine leukemia model. Mechanistically, WP1130 induced the degradation of WT1 by positively affecting the ubiquitination of WT1 protein. Conclusions Our results indicate that WT1 is required for the development of AML. WP1130 exhibits anti-leukemic activity by inhibiting the WT1-BCL2L2 axis, which may represent a new acute myeloid leukemia therapy target.
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Affiliation(s)
- Bin Zhou
- Laboratory of Internal Medicine, The First Affiliated Hospital of Wenzhou Medical University, 1 Xuefubei Street, Ouhai District, Wenzhou, 325000, Zhejiang, China
| | - Xianghong Jin
- Department of Hematology, The First Affiliated Hospital of Wenzhou Medical University, 1 Xuefubei Street, Ouhai District, Wenzhou, 325000, Zhejiang, China
| | - Weiwei Jin
- Department of Obstetrics and Gynecology, Wenzhou Hospital of Integrated Traditional Chinese and Western Medicine, Wenzhou, 325000, Zhejiang, China
| | - Xingzhou Huang
- Laboratory of Internal Medicine, The First Affiliated Hospital of Wenzhou Medical University, 1 Xuefubei Street, Ouhai District, Wenzhou, 325000, Zhejiang, China
| | - Yanfei Wu
- Laboratory of Internal Medicine, The First Affiliated Hospital of Wenzhou Medical University, 1 Xuefubei Street, Ouhai District, Wenzhou, 325000, Zhejiang, China
| | - Haiying Li
- Laboratory of Internal Medicine, The First Affiliated Hospital of Wenzhou Medical University, 1 Xuefubei Street, Ouhai District, Wenzhou, 325000, Zhejiang, China
| | - Weijian Zhu
- Laboratory of Internal Medicine, The First Affiliated Hospital of Wenzhou Medical University, 1 Xuefubei Street, Ouhai District, Wenzhou, 325000, Zhejiang, China
| | - Xiaoyi Qin
- Department of Hematology, The First Affiliated Hospital of Wenzhou Medical University, 1 Xuefubei Street, Ouhai District, Wenzhou, 325000, Zhejiang, China
| | - Haige Ye
- Department of Hematology, The First Affiliated Hospital of Wenzhou Medical University, 1 Xuefubei Street, Ouhai District, Wenzhou, 325000, Zhejiang, China.
| | - Shenmeng Gao
- Laboratory of Internal Medicine, The First Affiliated Hospital of Wenzhou Medical University, 1 Xuefubei Street, Ouhai District, Wenzhou, 325000, Zhejiang, China.
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Pace J, Paladugu P, Das B, He JC, Mallipattu SK. Targeting STAT3 signaling in kidney disease. Am J Physiol Renal Physiol 2019; 316:F1151-F1161. [PMID: 30943069 DOI: 10.1152/ajprenal.00034.2019] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The Janus kinase/signal transducer and activator of transcription (JAK/STAT) signaling pathway is a multifaceted transduction system that regulates cellular responses to incoming signaling ligands. STAT3 is a central member of the JAK/STAT signaling cascade and has long been recognized for its increased transcriptional activity in cancers and autoimmune disorders but has only recently been in the spotlight for its role in the progression of kidney disease. Although genetic knockout and manipulation studies have demonstrated the salutary benefits of inhibiting STAT3 activity in several kidney disease models, pharmacological inhibition has yet to make it to the clinical forefront. In recent years, significant effort has been aimed at suppressing STAT3 activation for treatment of cancers, which has led to the development of a wide variety of STAT3 inhibitors, but only a handful have been tested in kidney disease models. Here, we review the detrimental role of dysregulated STAT3 activation in a variety of kidney diseases and the current progress in the treatment of kidney diseases with pharmacological inhibition of STAT3 activity.
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Affiliation(s)
- Jesse Pace
- Division of Nephrology, Department of Medicine, Stony Brook University , Stony Brook, New York
| | - Praharshasai Paladugu
- Division of Nephrology, Department of Medicine, Stony Brook University , Stony Brook, New York
| | - Bhaskar Das
- Division of Nephrology, Department of Medicine, Icahn School of Medicine at Mount Sinai , New York, New York
| | - John C He
- Division of Nephrology, Department of Medicine, Icahn School of Medicine at Mount Sinai , New York, New York
| | - Sandeep K Mallipattu
- Division of Nephrology, Department of Medicine, Stony Brook University , Stony Brook, New York.,Renal Section, Northport Veterans Affairs Medical Center, Northport, New York
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Malouf C, Ottersbach K. Molecular processes involved in B cell acute lymphoblastic leukaemia. Cell Mol Life Sci 2018; 75:417-446. [PMID: 28819864 PMCID: PMC5765206 DOI: 10.1007/s00018-017-2620-z] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Revised: 08/01/2017] [Accepted: 08/04/2017] [Indexed: 12/19/2022]
Abstract
B cell leukaemia is one of the most frequent malignancies in the paediatric population, but also affects a significant proportion of adults in developed countries. The majority of infant and paediatric cases initiate the process of leukaemogenesis during foetal development (in utero) through the formation of a chromosomal translocation or the acquisition/deletion of genetic material (hyperdiploidy or hypodiploidy, respectively). This first genetic insult is the major determinant for the prognosis and therapeutic outcome of patients. B cell leukaemia in adults displays similar molecular features as its paediatric counterpart. However, since this disease is highly represented in the infant and paediatric population, this review will focus on this demographic group and summarise the biological, clinical and epidemiological knowledge on B cell acute lymphoblastic leukaemia of four well characterised subtypes: t(4;11) MLL-AF4, t(12;21) ETV6-RUNX1, t(1;19) E2A-PBX1 and t(9;22) BCR-ABL1.
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Affiliation(s)
- Camille Malouf
- MRC Centre for Regenerative Medicine, The University of Edinburgh, 5 Little France Drive, Edinburgh, EH16 4UU, UK
| | - Katrin Ottersbach
- MRC Centre for Regenerative Medicine, The University of Edinburgh, 5 Little France Drive, Edinburgh, EH16 4UU, UK.
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Liu JF, Deng WW, Chen L, Li YC, Wu L, Ma SR, Zhang WF, Bu LL, Sun ZJ. Inhibition of JAK2/STAT3 reduces tumor-induced angiogenesis and myeloid-derived suppressor cells in head and neck cancer. Mol Carcinog 2017; 57:429-439. [PMID: 29215754 DOI: 10.1002/mc.22767] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Revised: 11/19/2017] [Accepted: 11/20/2017] [Indexed: 12/14/2022]
Abstract
Angiogenesis is an essential event in tumor growth and metastasis, and immune system also contributes to the tumor evasion. Emerging evidences have suggested the bidirectional link between angiogenesis and immunosuppression. Myeloid-derived suppressor cell (MDSC) is a kind of immunosuppressive cells and plays an important role in this process. However, the actual regulatory mechanisms of angiogenesis and MDSCs in head and neck squamous cell carcinoma (HNSCC) were unclear. In this study, through analyzing the immunohistochemistry staining of human HNSCC tissue microarray, we found that the microvascular density (MVD) was significantly increased in HNSCC patients. We also characterized angiogenic factors p-STAT3, VEGFA, CK2, and MDSCs marker CD11b in HNSCC tissue array, and found the close expression correlation among these markers. To determine the role of JAK2/STAT3 pathway in tumor microenvironment of HNSCC, we utilized AG490 (an inhibitor of JAK2/STAT3) for further research. Results showed that inhibition of JAK2/STAT3 suppressed angiogenesis by decreasing VEGFA and HIF1-α both in vitro and vivo. Moreover, in HNSCC transgenic mouse model, inhibiting JAK2/STAT3 not only suppressed angiogenesis but also reduced MDSCs in the tumor microenvironment through suppressing VEGFA and CK2. Our findings demonstrated the close relationship between angiogenesis and MDSCs in HNSCC, and inhibition of JAK2/STAT3 could reduce tumor-induced angiogenesis and decrease MDSCs.
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Affiliation(s)
- Jian-Feng Liu
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory of Oral Biomedicine Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, China
| | - Wei-Wei Deng
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory of Oral Biomedicine Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, China
| | - Lei Chen
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory of Oral Biomedicine Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, China
| | - Yi-Cun Li
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory of Oral Biomedicine Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, China
| | - Lei Wu
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory of Oral Biomedicine Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, China
| | - Si-Rui Ma
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory of Oral Biomedicine Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, China
| | - Wen-Feng Zhang
- Department of Oral Maxillofacial-Head Neck Oncology, School and Hospital of Stomatology, Wuhan University, Wuhan, China
| | - Lin-Lin Bu
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory of Oral Biomedicine Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, China.,Department of Oral Maxillofacial-Head Neck Oncology, School and Hospital of Stomatology, Wuhan University, Wuhan, China
| | - Zhi-Jun Sun
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory of Oral Biomedicine Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, China.,Department of Oral Maxillofacial-Head Neck Oncology, School and Hospital of Stomatology, Wuhan University, Wuhan, China
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6
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Chang CH, Liu WT, Hung HC, Gean CY, Tsai HM, Su CL, Gean PW. Synergistic inhibition of tumor growth by combination treatment with drugs against different subpopulations of glioblastoma cells. BMC Cancer 2017; 17:905. [PMID: 29284440 PMCID: PMC5747127 DOI: 10.1186/s12885-017-3924-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Accepted: 12/14/2017] [Indexed: 12/28/2022] Open
Abstract
Background Glioma stem cells (GSCs) contribute to tumor recurrence and drug resistance. This study characterizes the tumorigenesis of CD133+ cells and their sensitivity to pharmacological inhibition. Methods GSCs from human U87 and rat C6 glioblastoma cell lines were isolated via magnetic cell sorting using CD133 as a cancer stem cell marker. Cell proliferation was determined using the WST-1 assay. An intracranial mouse model and bioluminescence imaging were used to assess the effects of drugs on tumor growth in vivo. Results CD133+ cells expressed stem cell markers and exhibited self-renewal and enhanced tumor formation. Minocycline (Mino) was more effective in reducing the survival rate of CD133+ cells, whereas CD133− cells were more sensitive to inhibition by the signal transducer and activator of transcription 3 (STAT3) inhibitor. Inhibition of STAT3 decreased the expression of CD133+ stem cell markers. The combination of Mino and STAT3 inhibitor synergistically reduced the cell viability of glioma cells. Furthermore, this combination synergistically suppressed tumor growth in nude mice. Conclusion The results suggest that concurrent targeting of different subpopulations of glioblastoma cells may be an effective therapeutic strategy for patients with malignant glioma.
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Affiliation(s)
- Chia-Hsin Chang
- Department of Pharmacology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Wei-Ting Liu
- Department of Pharmacology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Hui-Chi Hung
- Department of Pharmacology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Chia-Yu Gean
- Department of Diagnostic Radiology, National Cheng Kung University Hospital, Tainan, Taiwan
| | - Hong-Ming Tsai
- Department of Diagnostic Radiology, National Cheng Kung University Hospital, Tainan, Taiwan
| | - Chun-Lin Su
- Department of Pharmacology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Po-Wu Gean
- Department of Pharmacology, College of Medicine, National Cheng Kung University, Tainan, Taiwan. .,Department of Biotechnology and Bioindustry Sciences, College of Bioscience and Biotechnology, National Cheng Kung University, Tainan, Taiwan.
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Role of ZNF224 in c-Myc repression and imatinib responsiveness in chronic myeloid leukemia. Oncotarget 2017; 9:3417-3431. [PMID: 29423056 PMCID: PMC5790473 DOI: 10.18632/oncotarget.23283] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Accepted: 11/17/2017] [Indexed: 12/22/2022] Open
Abstract
The transcription factor ZNF224 plays a key proapoptotic role in chronic myelogenous leukemia (CML), by modulating Wilms Tumor protein 1 (WT1) dependent apoptotic genes transcription. Recently, we demonstrated that Bcr-Abl signaling represses ZNF224 expression in Bcr-Abl positive CML cell lines and in CML patients. Interestingly, Imatinib and second-generation tyrosine kinase inhibitors specifically increase ZNF224 expression. On the other hand, Bcr-Abl positively modulates, via JAK2 activation, the expression of the c-Myc oncogene, which is required for Bcr-Abl oncogenic transformation in CML. Consequently, JAK2 inhibitors represent promising molecular therapeutic tools in CML. In this work, we demonstrate that ZNF224 is a novel transcriptional repressor of c-Myc in CML. We also show that ZNF224 induction by Imatinib and AG490, a specific JAK2 inhibitor, is responsible for the transcriptional repression of c-MYC, thus highlighting the crucial role of the ZNF224/c-Myc axis in Imatinib responsiveness. Interestingly, we also report that ZNF224 is induced by AG490 in Imatinib-resistant CML cells, leading to c-Myc repression and apoptosis induction. These findings suggest that the development of molecular tools able to induce ZNF224 expression could provide promising means to bypass Imatinib resistance in CML.
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Kalkat M, De Melo J, Hickman KA, Lourenco C, Redel C, Resetca D, Tamachi A, Tu WB, Penn LZ. MYC Deregulation in Primary Human Cancers. Genes (Basel) 2017; 8:genes8060151. [PMID: 28587062 PMCID: PMC5485515 DOI: 10.3390/genes8060151] [Citation(s) in RCA: 227] [Impact Index Per Article: 32.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Revised: 05/19/2017] [Accepted: 05/19/2017] [Indexed: 12/12/2022] Open
Abstract
MYC regulates a complex biological program by transcriptionally activating and repressing its numerous target genes. As such, MYC is a master regulator of many processes, including cell cycle entry, ribosome biogenesis, and metabolism. In cancer, the activity of the MYC transcriptional network is frequently deregulated, contributing to the initiation and maintenance of disease. Deregulation often leads to constitutive overexpression of MYC, which can be achieved through gross genetic abnormalities, including copy number alterations, chromosomal translocations, increased enhancer activity, or through aberrant signal transduction leading to increased MYC transcription or increased MYC mRNA and protein stability. Herein, we summarize the frequency and modes of MYC deregulation and describe both well-established and more recent findings in a variety of cancer types. Notably, these studies have highlighted that with an increased appreciation for the basic mechanisms deregulating MYC in cancer, new therapeutic vulnerabilities can be discovered and potentially exploited for the inhibition of this potent oncogene in cancer.
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Affiliation(s)
- Manpreet Kalkat
- Department of Medical Biophysics, University of Toronto, Toronto, ON M5G 1L7, Canada.
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2M9, Canada.
| | - Jason De Melo
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2M9, Canada.
| | - Katherine Ashley Hickman
- Department of Medical Biophysics, University of Toronto, Toronto, ON M5G 1L7, Canada.
- Sunnybrook Research Institute, Toronto, ON M4N 3M5, Canada.
| | - Corey Lourenco
- Department of Medical Biophysics, University of Toronto, Toronto, ON M5G 1L7, Canada.
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2M9, Canada.
| | - Cornelia Redel
- Department of Medical Biophysics, University of Toronto, Toronto, ON M5G 1L7, Canada.
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2M9, Canada.
| | - Diana Resetca
- Department of Medical Biophysics, University of Toronto, Toronto, ON M5G 1L7, Canada.
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2M9, Canada.
| | - Aaliya Tamachi
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2M9, Canada.
| | - William B Tu
- Department of Medical Biophysics, University of Toronto, Toronto, ON M5G 1L7, Canada.
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2M9, Canada.
| | - Linda Z Penn
- Department of Medical Biophysics, University of Toronto, Toronto, ON M5G 1L7, Canada.
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2M9, Canada.
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9
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Rethinking JAK2 inhibition: towards novel strategies of more specific and versatile janus kinase inhibition. Leukemia 2017; 31:1023-1038. [DOI: 10.1038/leu.2017.43] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Revised: 12/16/2016] [Accepted: 01/10/2017] [Indexed: 12/19/2022]
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10
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Yang R, Rincon M. Mitochondrial Stat3, the Need for Design Thinking. Int J Biol Sci 2016; 12:532-44. [PMID: 27019635 PMCID: PMC4807418 DOI: 10.7150/ijbs.15153] [Citation(s) in RCA: 91] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2016] [Accepted: 02/12/2016] [Indexed: 12/20/2022] Open
Abstract
Stat3 has been studied extensively as a transcription factor, however the finding that Stat3 also localizes to mitochondria has opened a new area to discover non-classical functions. Here we review the current knowledge of mitochondrial Stat3 as a regulator of the electron transport chain (ETC) and its impact on mitochondrial production of ATP and ROS. We also describe recent findings identifying Stat3 as a regulator of mitochondrial Ca(2+) homeostasis through its effect on the ETC. It is becoming evident that these non-classical functions of Stat3 can have a major impact on cancer progression, cardiovascular diseases, and inflammatory diseases. Therefore, mitochondrial Stat3 functions challenge the current design of therapies that solely target Stat3 as a transcription factor and suggest the need for "design thinking," which leads to the development of novel strategies, to intervene the Stat3 pathway.
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11
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Inhibition of JAK2 Reverses Paclitaxel Resistance in Human Ovarian Cancer Cells. Int J Gynecol Cancer 2015; 25:1557-64. [DOI: 10.1097/igc.0000000000000550] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
ObjectiveResistance to chemotherapy is a major factor that limits the postsurgical survival of ovarian cancer patients. Janus-activated kinase 2 (JAK2) has been implicated in cancer cell survival and the development of drug resistance in ovarian cancers. In the present study, we sought to determine whether inhibition of JAK2 reverses drug resistance in OC3/TAX300 cells, a paclitaxel-resistant human ovarian cancer cell line previously established in our laboratory.MethodsOC3/TAX300 cells were transduced with lentivirus expressing small interference RNA (siRNA) against JAK2 and treated with JAK2 kinase inhibitor AG490.ResultsTreatment with JAK2-siRNA markedly decreased the messenger RNA and protein of JAK2 as determined by real-time polymerase chain reaction and Western blot analysis. OC3/TAX300 cells treated with JAK2-siRNA exhibited stalled growth, increased cell cycle arrest in G2/M phase, and enhanced apoptosis in response to paclitaxel. In keeping with this, JAK2-siRNA also inhibited the expression of multidrug resistance protein 1. To determine whether JAK2 promotes paclitaxel resistance via phosphorylation of signal transducer and activator of transcription 3 (STAT3), a transcription factor known to be involved in resistance to chemotherapy, we treated OC3/TAX300 cells with JAK2 kinase inhibitor AG490. Of note, AG490 reduced the level of p-STAT3 and inhibited the expression of multidrug resistance protein 1 in a dose-dependent manner.ConclusionsCollectively, we conclude that the JAK2-STAT3 pathway promotes the development of paclitaxel resistance via upregulating the expression of prosurvival and antiapoptotic genes. Targeting this pathway may be effective in reversing resistance to chemotherapy in ovarian cancers.
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12
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Pilati C, Zucman-Rossi J. Mutations leading to constitutive active gp130/JAK1/STAT3 pathway. Cytokine Growth Factor Rev 2015; 26:499-506. [DOI: 10.1016/j.cytogfr.2015.07.010] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2015] [Accepted: 07/01/2015] [Indexed: 12/21/2022]
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13
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Tortorella SM, Hung A, Karagiannis TC. The implication of cancer progenitor cells and the role of epigenetics in the development of novel therapeutic strategies for chronic myeloid leukemia. Antioxid Redox Signal 2015; 22:1425-62. [PMID: 25366930 DOI: 10.1089/ars.2014.6096] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
SIGNIFICANCE Chronic myeloid leukemia (CML) involves the malignant transformation of hematopoietic stem cells, defined largely by the Philadelphia chromosome and expression of the breakpoint cluster region-Abelson (BCR-ABL) oncoprotein. Pharmacological tyrosine kinase inhibitors (TKIs), including imatinib mesylate, have overcome limitations in conventional treatment for the improved clinical management of CML. RECENT ADVANCES Accumulated evidence has led to the identification of a subpopulation of quiescent leukemia progenitor cells with stem-like self renewal properties that may initiate leukemogenesis, which are also shown to be present in residual disease due to their insensitivity to tyrosine kinase inhibition. CRITICAL ISSUES The characterization of quiescent leukemia progenitor cells as a unique cell population in CML pathogenesis has become critical with the complete elucidation of mechanisms involved in their survival independent of BCR-ABL that is important in the development of novel anticancer strategies. Understanding of these functional pathways in CML progenitor cells will allow for their selective therapeutic targeting. In addition, disease pathogenesis and drug responsiveness is also thought to be modulated by epigenetic regulatory mechanisms such as DNA methylation, histone acetylation, and microRNA expression, with a capacity to control CML-associated gene transcription. FUTURE DIRECTIONS A number of compounds in combination with TKIs are under preclinical and clinical investigation to assess their synergistic potential in targeting leukemic progenitor cells and/or the epigenome in CML. Despite the collective promise, further research is required in order to refine understanding, and, ultimately, advance antileukemic therapeutic strategies.
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Affiliation(s)
- Stephanie M Tortorella
- 1 Epigenomic Medicine, Baker IDI Heart and Diabetes Institute, The Alfred Medical Research and Education Precinct , Melbourne, Australia
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Drenckhahn JD, Strasen J, Heinecke K, Langner P, Yin KV, Skole F, Hennig M, Spallek B, Fischer R, Blaschke F, Heuser A, Cox TC, Black MJ, Thierfelder L. Impaired myocardial development resulting in neonatal cardiac hypoplasia alters postnatal growth and stress response in the heart. Cardiovasc Res 2015; 106:43-54. [PMID: 25661081 DOI: 10.1093/cvr/cvv028] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
AIMS Foetal growth has been proposed to influence cardiovascular health in adulthood, a process referred to as foetal programming. Indeed, intrauterine growth restriction in animal models alters heart size and cardiomyocyte number in the perinatal period, yet the consequences for the adult or challenged heart are largely unknown. The aim of this study was to elucidate postnatal myocardial growth pattern, left ventricular function, and stress response in the adult heart after neonatal cardiac hypoplasia in mice. METHODS AND RESULTS Utilizing a new mouse model of impaired cardiac development leading to fully functional but hypoplastic hearts at birth, we show that myocardial mass is normalized until early adulthood by accelerated physiological cardiomyocyte hypertrophy. Compensatory hypertrophy, however, cannot be maintained upon ageing, resulting in reduced organ size without maladaptive myocardial remodelling. Angiotensin II stress revealed aberrant cardiomyocyte growth kinetics in adult hearts after neonatal hypoplasia compared with normally developed controls, characterized by reversible overshooting hypertrophy. This exaggerated growth mainly depends on STAT3, whose inhibition during angiotensin II treatment reduces left ventricular mass in both groups but causes contractile dysfunction in developmentally impaired hearts only. Whereas JAK/STAT3 inhibition reduces cardiomyocyte cross-sectional area in the latter, it prevents fibrosis in control hearts, indicating fundamentally different mechanisms of action. CONCLUSION Impaired prenatal development leading to neonatal cardiac hypoplasia alters postnatal cardiac growth and stress response in vivo, thereby linking foetal programming to organ size control in the heart.
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Affiliation(s)
- Jörg-Detlef Drenckhahn
- Max-Delbrück-Center for Molecular Medicine, Robert-Rössle-Straße 10, Berlin 13125, Germany
| | - Jette Strasen
- Max-Delbrück-Center for Molecular Medicine, Robert-Rössle-Straße 10, Berlin 13125, Germany
| | - Kirsten Heinecke
- Max-Delbrück-Center for Molecular Medicine, Robert-Rössle-Straße 10, Berlin 13125, Germany
| | - Patrick Langner
- Max-Delbrück-Center for Molecular Medicine, Robert-Rössle-Straße 10, Berlin 13125, Germany
| | - Kom Voy Yin
- Department of Anatomy and Developmental Biology, Monash University, Melbourne, Australia
| | - Friederike Skole
- Max-Delbrück-Center for Molecular Medicine, Robert-Rössle-Straße 10, Berlin 13125, Germany
| | - Maria Hennig
- Max-Delbrück-Center for Molecular Medicine, Robert-Rössle-Straße 10, Berlin 13125, Germany
| | - Bastian Spallek
- Experimental and Clinical Research Center, Charité Medical Faculty, Max-Delbrück-Center for Molecular Medicine, Berlin, Germany
| | - Robert Fischer
- Experimental and Clinical Research Center, Charité Medical Faculty, Max-Delbrück-Center for Molecular Medicine, Berlin, Germany
| | - Florian Blaschke
- Max-Delbrück-Center for Molecular Medicine, Robert-Rössle-Straße 10, Berlin 13125, Germany Charité Universitätsmedizin Berlin, Medizinische Klinik mit Schwerpunkt Kardiologie, Berlin, Germany
| | - Arnd Heuser
- Max-Delbrück-Center for Molecular Medicine, Robert-Rössle-Straße 10, Berlin 13125, Germany
| | - Timothy C Cox
- Department of Anatomy and Developmental Biology, Monash University, Melbourne, Australia Department of Pediatrics, University of Washington, Seattle, USA Center of Developmental Biology and Regenerative Medicine, Seattle Children's Research Institute, Seattle, USA
| | - Mary Jane Black
- Department of Anatomy and Developmental Biology, Monash University, Melbourne, Australia
| | - Ludwig Thierfelder
- Max-Delbrück-Center for Molecular Medicine, Robert-Rössle-Straße 10, Berlin 13125, Germany
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Hosseinzadeh Z, Almilaji A, Honisch S, Pakladok T, Liu G, Bhavsar SK, Ruth P, Shumilina E, Lang F. Upregulation of the large conductance voltage- and Ca2+-activated K+ channels by Janus kinase 2. Am J Physiol Cell Physiol 2014; 306:C1041-9. [PMID: 24696148 DOI: 10.1152/ajpcell.00209.2013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The iberiotoxin-sensitive large conductance voltage- and Ca(2+)-activated potassium (BK) channels (maxi-K(+)-channels) hyperpolarize the cell membrane thus supporting Ca(2+) entry through Ca(2+)-release activated Ca(2+) channels. Janus kinase-2 (JAK2) has been identified as novel regulator of ion transport. To explore whether JAK2 participates in the regulation of BK channels, cRNA encoding Ca(2+)-insensitive BK channels (BK(M513I+Δ899-903)) was injected into Xenopus oocytes with or without cRNA encoding wild-type JAK2, gain-of-function (V617F)JAK2, or inactive (K882E)JAK2. K(+) conductance was determined by dual electrode voltage clamp and BK-channel protein abundance by confocal microscopy. In A204 alveolar rhabdomyosarcoma cells, iberiotoxin-sensitive K(+) current was determined utilizing whole cell patch clamp. A204 cells were further transfected with JAK2 and BK-channel transcript, and protein abundance was quantified by RT-PCR and Western blotting, respectively. As a result, the K(+) current in BK(M513I+Δ899-903)-expressing oocytes was significantly increased following coexpression of JAK2 or (V617F)JAK2 but not (K882E)JAK2. Coexpression of the BK channel with (V617F)JAK2 but not (K882E)JAK2 enhanced BK-channel protein abundance in the oocyte cell membrane. Exposure of BK-channel and (V617F)JAK2-expressing oocytes to the JAK2 inhibitor AG490 (40 μM) significantly decreased K(+) current. Inhibition of channel insertion by brefeldin A (5 μM) decreased the K(+) current to a similar extent in oocytes expressing the BK channel alone and in oocytes expressing the BK channel and (V617F)JAK2. The iberiotoxin (50 nM)-sensitive K(+) current in rhabdomyosarcoma cells was significantly decreased by AG490 pretreatment (40 μM, 12 h). Moreover, overexpression of JAK2 in A204 cells significantly enhanced BK channel mRNA and protein abundance. In conclusion, JAK2 upregulates BK channels by increasing channel protein abundance in the cell membrane.
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Affiliation(s)
| | - Ahmad Almilaji
- Department of Physiology, University of Tübingen, Tübingen, Germany; and
| | - Sabina Honisch
- Department of Physiology, University of Tübingen, Tübingen, Germany; and
| | - Tatsiana Pakladok
- Department of Physiology, University of Tübingen, Tübingen, Germany; and
| | - GuoXing Liu
- Department of Physiology, University of Tübingen, Tübingen, Germany; and
| | - Shefalee K Bhavsar
- Department of Physiology, University of Tübingen, Tübingen, Germany; and
| | - Peter Ruth
- Institute of Pharmacy, Department of Pharmacology and Toxicology, University of Tübingen, Tübingen, Germany
| | | | - Florian Lang
- Department of Physiology, University of Tübingen, Tübingen, Germany; and
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JOUNG YOUNHEE, NA YOONMI, YOO YOUNGBUM, DARVIN PRAMOD, SP NIPIN, KANG DONGYOUNG, KIM SANGYOON, KIM HONGSUP, CHOI YOONHEE, LEE HAKKYO, PARK KYUNGDO, CHO BYUNGWOOK, KIM HEUISOO, PARK JONGHWAN, YANG YOUNGMOK. Combination of AG490, a Jak2 inhibitor, and methylsulfonylmethane synergistically suppresses bladder tumor growth via the Jak2/STAT3 pathway. Int J Oncol 2014; 44:883-95. [DOI: 10.3892/ijo.2014.2250] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Accepted: 12/11/2013] [Indexed: 11/06/2022] Open
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17
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Poussin K, Pilati C, Couchy G, Calderaro J, Bioulac-Sage P, Bacq Y, Paradis V, Leteurtre E, Sturm N, Ramos J, Guettier C, Bardier-Dupas A, Boulai A, Wendum D, Selves J, Izard T, Nault JC, Zucman-Rossi J. Biochemical and functional analyses of gp130 mutants unveil JAK1 as a novel therapeutic target in human inflammatory hepatocellular adenoma. Oncoimmunology 2014; 2:e27090. [PMID: 24501689 PMCID: PMC3913689 DOI: 10.4161/onci.27090] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2013] [Accepted: 11/04/2013] [Indexed: 01/05/2023] Open
Abstract
Inflammatory hepatocellular adenomas (IHCAs) are benign liver lesions that can be characterized histologically by the presence of an inflammatory infiltrate and at the molecular level by the overexpression of acute phase inflammatory response genes. Recurrent somatic mutations of the interleukin-6 (IL-6) signal transducer (IL6ST) locus, encoding the critical component of the IL-6 signal transduction machinery gp130, are present in 60% of IHCAs and in a subset (2%) of hepatocellular carcinoma (HCCs). By screening of 256 human hepatic adenoma specimens (the largest genetic analysis of IL6ST performed to date in this setting), we identified 24 distinct somatic IL6ST mutations among 66 mutant adenomas. The functional analysis of nine different gp130 mutants expressed in hepatic cancer cell lines consistently revealed the constitutive and IL-6-independent activation of the JAK/STAT signaling pathway. We further demonstrated that the signaling activity of mutant gp130 in IHCA remains responsive to suppressor of cytokine signaling 3 (SOCS3), a physiological gp130 inhibitor. Specifically, cells expressing a double mutant variant of gp130 with a disrupted SOCS3-binding site at residue 759 (Y186/Y759F) displayed a hyperactivation of signal transducer and activator of transcription 3 (STAT3) as compared with cells expressing the endogenous IHCA-associated Y186 gp130 mutant. Notably, we identified that constitutive signaling via gp130 in IHCA requires the Janus kinase family member JAK1, but not JAK2 or tyrosine kinase 2. In support of this notion, AG490, a tyrosine kinase inhibitor that selectively blocks JAK2, had no effect on gp130 activity. In stark contrast, we showed that ruxolitinib, a JAK1/JAK2-selective tyrosine kinase inhibitor used to treat patients with myelofibrosis, dramatically impaired JAK1-STAT signaling downstream of all IHCA-associated gp130 mutants. In conclusion, our findings provide a rationale for the use of JAK1 inhibitors for the treatment of HCAs expressing mutant gp130 as well as a subset of HCCs that bear similar mutations.
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Affiliation(s)
- Karine Poussin
- INSERM, UMR-674; Génomique fonctionnelle des tumeurs solides; IUH; Paris, France ; Université Paris Descartes; Labex Immuno-oncology; Sorbonne Paris Cité; Faculté de Médecine; Paris, France
| | - Camilla Pilati
- INSERM, UMR-674; Génomique fonctionnelle des tumeurs solides; IUH; Paris, France ; Université Paris Descartes; Labex Immuno-oncology; Sorbonne Paris Cité; Faculté de Médecine; Paris, France
| | - Gabrielle Couchy
- INSERM, UMR-674; Génomique fonctionnelle des tumeurs solides; IUH; Paris, France ; Université Paris Descartes; Labex Immuno-oncology; Sorbonne Paris Cité; Faculté de Médecine; Paris, France
| | - Julien Calderaro
- INSERM, UMR-674; Génomique fonctionnelle des tumeurs solides; IUH; Paris, France ; Université Paris Descartes; Labex Immuno-oncology; Sorbonne Paris Cité; Faculté de Médecine; Paris, France ; Assistance Publique-Hôpitaux de Paris; Department of Pathology; CHU Henri Mondor; Créteil, France
| | - Paulette Bioulac-Sage
- Inserm, UMR-1053; Université Victor Segalen Bordeaux 2; Bordeaux, France ; CHU de Bordeaux; Pellegrin Hospital; Department of Pathology; Bordeaux, France
| | - Yannick Bacq
- Service d'Hépatogastroentérologie; Hôpital Trousseau; CHRU de Tours; Tours, France
| | - Valérie Paradis
- Assistance Publique-Hôpitaux de Paris; Department of Pathology; Beaujon Hospital; Université Paris Diderot; Clichy, France
| | - Emmanuelle Leteurtre
- Université de Lille 2; Lille, France ; Institut de Pathologie; CHRU de Lille; Lille, France ; INSERM U837; Lille, France
| | - Nathalie Sturm
- Depatment of Pathology; CHU Grenoble; Hôpital Albert Michallon; La Tronche, France
| | - Jeanne Ramos
- Department of Pathology; Gui de Chauliac Hospital; Université Montpellier-Nîmes; Montpellier, France
| | - Catherine Guettier
- Department of Pathology; Assistance Publique-Hôpitaux de Paris; Hôpital Paul Brousse; Villejuif, France
| | - Armelle Bardier-Dupas
- Assistance Publique-Hôpitaux de Paris; Department of Pathology; Groupe Hospitalier Pitié-Salpêtrière; Université Pierre et Marie Curie; Paris, France
| | - Anais Boulai
- INSERM, UMR-674; Génomique fonctionnelle des tumeurs solides; IUH; Paris, France ; Université Paris Descartes; Labex Immuno-oncology; Sorbonne Paris Cité; Faculté de Médecine; Paris, France
| | - Dominique Wendum
- UPMC Univ Paris 06; UMRS 938; CdR Saint-Antoine; Paris, France ; INSERM, UMRS 938; CdR Saint-Antoine; Paris, France ; AP-HP, Hôpital St Antoine; Service d'Anatomie Pathologique; Paris, France
| | - Janick Selves
- Purpan Hospital; Pathology and Cancer Research Centre of Toulouse; Inserm UMR 1037/CNRS-ERL 5294/Toulouse 3 University; Markers & Targets for Digestive Cancer Biotherapy; Toulouse, France
| | - Tina Izard
- Department of Cancer Biology; The Scripps Research Institute; Scripps Florida; Jupiter, Florida USA
| | - Jean-Charles Nault
- INSERM, UMR-674; Génomique fonctionnelle des tumeurs solides; IUH; Paris, France ; Université Paris Descartes; Labex Immuno-oncology; Sorbonne Paris Cité; Faculté de Médecine; Paris, France
| | - Jessica Zucman-Rossi
- INSERM, UMR-674; Génomique fonctionnelle des tumeurs solides; IUH; Paris, France ; Université Paris Descartes; Labex Immuno-oncology; Sorbonne Paris Cité; Faculté de Médecine; Paris, France
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18
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Wang G, Wang JJ, Chen XL, Du SM, Li DS, Pei ZJ, Lan H, Wu LB. The JAK2/STAT3 and mitochondrial pathways are essential for quercetin nanoliposome-induced C6 glioma cell death. Cell Death Dis 2013; 4:e746. [PMID: 23907460 PMCID: PMC3763427 DOI: 10.1038/cddis.2013.242] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2013] [Revised: 06/02/2013] [Accepted: 06/03/2013] [Indexed: 01/12/2023]
Abstract
The formulation of quercetin nanoliposomes (QUE-NLs) has been shown to enhance QUE antitumor activity in C6 glioma cells. At high concentrations, QUE-NLs induce necrotic cell death. In this study, we probed the molecular mechanisms of QUE-NL-induced C6 glioma cell death and examined whether QUE-NL-induced programmed cell death involved Bcl-2 family and mitochondrial pathway through STAT3 signal transduction pathway. Downregulation of Bcl-2 and the overexpression of Bax by QUE-NL supported the involvement of Bcl-2 family proteins upstream of C6 glioma cell death. In addition, the activation of JAK2 and STAT3 were altered following exposure to QUE-NLs in C6 glioma cells, suggesting that QUE-NLs downregulated Bcl-2 mRNAs expression and enhanced the expression of mitochondrial mRNAs through STAT3-mediated signaling pathways either via direct or indirect mechanisms. There are several components such as ROS, mitochondrial, and Bcl-2 family shared by the necrotic and apoptotic pathways. Our studies indicate that the signaling cross point of the mitochondrial pathway and the JAK2/STAT3 signaling pathway in C6 glioma cell death is modulated by QUE-NLs. In conclusion, regulation of JAK2/STAT3 and ROS-mediated mitochondrial pathway agonists alone or in combination with treatment by QUE-NLs could be a more effective method of treating chemical-resistant glioma.
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Affiliation(s)
- G Wang
- Department of Pharmacy, Taihe Hospital, Hubei University of Medicine, Shiyan City, Hubei Province, People's Republic of China
| | - J J Wang
- Department of Pharmacy, Taihe Hospital, Hubei University of Medicine, Shiyan City, Hubei Province, People's Republic of China
| | - X L Chen
- Hubei Provincial Key Laboratory of Embryo Stem Cells, Shiyan City, Hubei Province, People's Republic of China
| | - S M Du
- Department of Pharmacy, Taihe Hospital, Hubei University of Medicine, Shiyan City, Hubei Province, People's Republic of China
| | - D S Li
- Hubei Provincial Key Laboratory of Embryo Stem Cells, Shiyan City, Hubei Province, People's Republic of China
| | - Z J Pei
- Hubei Provincial Key Laboratory of Embryo Stem Cells, Shiyan City, Hubei Province, People's Republic of China
| | - H Lan
- Department of Pharmacy, Taihe Hospital, Hubei University of Medicine, Shiyan City, Hubei Province, People's Republic of China
| | - L B Wu
- Hubei Provincial Key Laboratory of Embryo Stem Cells, Shiyan City, Hubei Province, People's Republic of China
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19
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Lee MJ, Lee JK, Choi JW, Lee CS, Sim JH, Cho CH, Lee KH, Cho IH, Chung MH, Kim HR, Ye SK. Interleukin-6 induces S100A9 expression in colonic epithelial cells through STAT3 activation in experimental ulcerative colitis. PLoS One 2012; 7:e38801. [PMID: 22962574 PMCID: PMC3433486 DOI: 10.1371/journal.pone.0038801] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2011] [Accepted: 05/10/2012] [Indexed: 12/27/2022] Open
Abstract
Background Intestinal epithelium is essential for maintaining normal intestinal homeostasis; its breakdown leads to chronic inflammatory pathologies, such as inflammatory bowel diseases (IBDs). Although high concentrations of S100A9 protein and interleukin-6 (IL-6) are found in patients with IBD, the expression mechanism of S100A9 in colonic epithelial cells (CECs) remains elusive. We investigated the role of IL-6 in S100A9 expression in CECs using a colitis model. Methods IL-6 and S100A9 expression, signal transducer and activator of transcription 3 (STAT3) phosphorylation, and infiltration of immune cells were analyzed in mice with dextran sulfate sodium (DSS)-induced colitis. The effects of soluble gp130-Fc protein (sgp130Fc) and S100A9 small interfering (si) RNA (si-S100A9) on DSS-induced colitis were evaluated. The molecular mechanism of S100A9 expression was investigated in an IL-6-treated Caco-2 cell line using chromatin immunoprecipitation assays. Results IL-6 concentrations increased significantly in the colon tissues of DSS-treated mice. sgp130Fc or si-S100A9 administration to DSS-treated mice reduced granulocyte infiltration in CECs and induced the down-regulation of S100A9 and colitis disease activity. Treatment with STAT3 inhibitors upon IL-6 stimulation in the Caco-2 cell line demonstrated that IL-6 mediated S100A9 expression through STAT3 activation. Moreover, we found that phospho-STAT3 binds directly to the S100A9 promoter. S100A9 may recruit immune cells into inflamed colon tissues. Conclusions Elevated S100A9 expression in CECs mediated by an IL-6/STAT3 signaling cascade may play an important role in the development of colitis.
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Affiliation(s)
- Min Jeoung Lee
- Department of Pharmacology, Seoul National University College of Medicine, Seoul, Republic of Korea
- Ischemic/Hypoxic Disease Institute, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Jin-Ku Lee
- Department of Pharmacology, Seoul National University College of Medicine, Seoul, Republic of Korea
- Ischemic/Hypoxic Disease Institute, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Ji Won Choi
- Department of Pharmacology, Seoul National University College of Medicine, Seoul, Republic of Korea
- Ischemic/Hypoxic Disease Institute, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Chang-Seok Lee
- Department of Pharmacology, Seoul National University College of Medicine, Seoul, Republic of Korea
- Ischemic/Hypoxic Disease Institute, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Ji Hyun Sim
- Department of Anatomy, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Chung-Hyun Cho
- Department of Pharmacology, Seoul National University College of Medicine, Seoul, Republic of Korea
- Ischemic/Hypoxic Disease Institute, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Kwang-Ho Lee
- Department of Biotechnology, College of Biomedical & Health Science, Konkuk University, Chungju, Republic of Korea
| | - Ik-Hyun Cho
- Department of Anatomy, College of Oriental Medicine, Kyung Hee University, Seoul, Republic of Korea
- Institute of Oriental Medicine, Kyung Hee University, Seoul, Republic of Korea
| | - Myung-Hee Chung
- Department of Pharmacology, Seoul National University College of Medicine, Seoul, Republic of Korea
- Ischemic/Hypoxic Disease Institute, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Hang-Rae Kim
- Department of Anatomy, Seoul National University College of Medicine, Seoul, Republic of Korea
- * E-mail: (SKY); (HK)
| | - Sang-Kyu Ye
- Department of Pharmacology, Seoul National University College of Medicine, Seoul, Republic of Korea
- Ischemic/Hypoxic Disease Institute, Seoul National University College of Medicine, Seoul, Republic of Korea
- * E-mail: (SKY); (HK)
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Esmailzadeh S, Jiang X. AHI-1: a novel signaling protein and potential therapeutic target in human leukemia and brain disorders. Oncotarget 2012; 2:918-34. [PMID: 22248740 PMCID: PMC3282096 DOI: 10.18632/oncotarget.405] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Progress in the understanding of the molecular and cellular mechanisms of human cancer, including human leukemia and lymphomas, has been spurred by cloning of fusion genes created by chromosomal translocations or by retroviral insertional mutagenesis; a number of oncogenes and tumor suppressors involved in development of a number of malignancies have been identified in this manner. The BCR-ABL fusion gene, originating in a multipotent hematopoietic stem cell, is the molecular signature of chronic myeloid leukemia (CML). Discovery of this fusion gene has led to the development of one of the first successful targeted molecular therapies for cancer (Imatinib). It illustrates the advances that can result from an understanding of the molecular basis of disease. However, there still remain many as yet unidentified mutations that may influence the initiation or progression of human diseases. Thus, identification and characterization of the mechanism of action of genes that contribute to human diseases is an important and opportune area of current research. One promising candidate as a potential therapeutic target is Abelson helper integration site-1(Ahi-1/AHI-1) that was identified by retroviral insertional mutagenesis in murine models of leukemia/lymphomas and is highly elevated in certain human lymphoma and leukemia stem/progenitor cells. It encodes a unique protein with a SH3 domain, multiple SH3 binding sites and a WD40-repeat domain, suggesting that the normal protein has novel signaling activities. A new AHI-1-BCR-ABL-JAK2 interaction complex has recently been identified and this complex regulates transforming activities and drug resistance in CML stem/progenitor cells. Importantly, AHI-1 has recently been identified as a susceptibility gene involved in a number of brain disorders, including Joubert syndrome. Therefore, understanding molecular functions of the AHI-1 gene could lead to important and novel insights into disease processes involved in specific types of diseases. Ultimately, this knowledge will set the stage for translation into new and more effective diagnostic and treatment strategies.
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Affiliation(s)
- Sharmin Esmailzadeh
- Terry Fox Laboratory, British Columbia Cancer Agency and Department of Medical Genetics, University of British Columbia, Vancouver, BC, Canada
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Hantschel O, Warsch W, Eckelhart E, Kaupe I, Grebien F, Wagner KU, Superti-Furga G, Sexl V. BCR-ABL uncouples canonical JAK2-STAT5 signaling in chronic myeloid leukemia. Nat Chem Biol 2012; 8:285-93. [DOI: 10.1038/nchembio.775] [Citation(s) in RCA: 141] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2011] [Accepted: 11/30/2011] [Indexed: 01/06/2023]
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Oh YS, Lee YJ, Park EY, Jun HS. Interleukin-6 treatment induces beta-cell apoptosis via STAT-3-mediated nitric oxide production. Diabetes Metab Res Rev 2011; 27:813-9. [PMID: 22069265 DOI: 10.1002/dmrr.1233] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
BACKGROUND Type 2 diabetes is characterized by progressive beta-cell failure and apoptosis is probably the main form of beta-cell death in this disease. It was reported that circulating levels of interleukin-6 are elevated in type 2 diabetic patients, but whether this is involved in the pathogenesis of type 2 diabetes is still debated. In this study, we examined whether interleukin-6 can induce beta-cell damage in vitro and elucidated its mechanisms. METHODS To examine the effect of interleukin-6 on beta cells, glucose-stimulated insulin secretion (GSIS) by enzyme immunoassay (EIA) method and cell apoptosis by propidium iodide and annexin-V staining were measured in a rat beta-cell line (INS-1 or INS-832/13) after treatment with interleukin-6. The expression of apoptosis-related molecules was measured using western blotting and nitric oxide (NO) production was measured using Griess assay. AG490 and N-monomethyl-L-arginine were used to inhibit Janus kinase-mediated signal transducers and activators of transcription signalling and NO production, respectively. RESULTS Exposure (48 h) of INS-1 cells to 20 ng/mL interleukin-6 significantly decreased GSIS as well as cell viability. We found that sub-G1/G0 population was increased as compared with untreated cells and expression of cleaved caspase-3, cleaved poly(ADP-ribose) polymerase, phosphorylated p38 mitogen-activated protein kinase and phosphorylated nuclear factor-κB was increased in interleukin-6-treated INS-1 cells. Interleukin-6 increased the amount of early apoptotic cells; this increase was blocked by AG490 or N-monomethyl-L-arginine treatment. Moreover, NO production, which is known to induce apoptosis, was increased by interleukin-6 treatment but abrogated in AG490-treated cells. CONCLUSION Our results show that exposure to interleukin-6 for 48 h can induce beta-cell death, in part via signal transducers and activators of transcription-3-mediated NO production.
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Affiliation(s)
- Yoon Sin Oh
- Lee Gil Ya Cancer and Diabetes Institute, Gachon University of Medicine and Science, Incheon, South Korea
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Kapuria V, Levitzki A, Bornmann WG, Maxwell D, Priebe W, Sorenson RJ, Showalter HD, Talpaz M, Donato NJ. A novel small molecule deubiquitinase inhibitor blocks Jak2 signaling through Jak2 ubiquitination. Cell Signal 2011; 23:2076-85. [PMID: 21855629 DOI: 10.1016/j.cellsig.2011.08.002] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2011] [Revised: 08/02/2011] [Accepted: 08/02/2011] [Indexed: 12/30/2022]
Abstract
AG490 is a tyrosine kinase inhibitor with activity against Jak2 and apoptotic activity in specific leukemias. Due to its weak kinase inhibitory activity and poor pharmacology, we conducted a cell-based screen for derivatives with improved Jak2 inhibition and activity in animals. Two hits emerged from an initial small chemical library screen, and more detailed structure-activity relationship studies led to the development of WP1130 with 50-fold greater activity in suppressing Jak2-dependent cytokine signaling than AG490. However, WP1130 did not directly suppress Jak2 kinase activity, but mediated Jak2 ubiquitination resulting in its trafficking through HDAC6 to perinuclear aggresomes without cytokine stimulation or SOCS-1 induction. Jak2 primarily contained K63-linked ubiquitin polymers, and mutation of this lysine blocked Jak2 ubiquitination and mobilization in WP1130-treated cells. Further analysis demonstrated that WP1130, but not AG490, acts as a deubiquitinating enzyme (DUB) inhibitor, possibly through a Michael addition reaction. We conclude that chemical modification of AG490 resulted in development of a DUB inhibitor with activity against a DUB capable of modulating Jak2 ubiquitination, trafficking and signal transduction.
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Affiliation(s)
- Vaibhav Kapuria
- Department of Internal Medicine, Division of Hematology-Oncology, University of Michigan Comprehensive Cancer Center, Ann Arbor, MI, USA.
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Ball S, Li C, Li PK, Lin J. The small molecule, LLL12, inhibits STAT3 phosphorylation and induces apoptosis in medulloblastoma and glioblastoma cells. PLoS One 2011; 6:e18820. [PMID: 21526200 PMCID: PMC3079737 DOI: 10.1371/journal.pone.0018820] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2010] [Accepted: 03/10/2011] [Indexed: 01/05/2023] Open
Abstract
Tumors of the central nervous system represent a major source of cancer-related deaths, with medulloblastoma and glioblastoma being the most common malignant brain tumors in children and adults respectively. While significant advances in treatment have been made, with the 5-year survival rate for medulloblastoma at 70-80%, treating patients under 3 years of age still poses a problem due to the deleterious effects of radiation on the developing brain, and the median survival for patients with glioblastoma is only 15 months. The transcription factor, STAT3, has been found constitutively activated in a wide variety of cancers and in recent years it has become an attractive therapeutic target. We designed a non-peptide small molecule STAT3 inhibitor, LLL12, using structure-based design. LLL12 was able to inhibit STAT3 phosphorylation, decrease cell viability and induce apoptosis in medulloblastoma and glioblastoma cell lines with elevated levels of p-STAT3 (Y705). IC(50) values for LLL12 were found to be between 1.07 µM and 5.98 µM in the five cell lines expressing phosphorylated STAT3. STAT3 target genes were found to be downregulated and a decrease in STAT3 DNA binding was observed following LLL12 treatment, indicating that LLL12 is an effective STAT3 inhibitor. LLL12 was also able to inhibit colony formation, wound healing and decreased IL-6 and LIF secretion. Our results suggest that LLL12 is a potent STAT3 inhibitor and that it may be a potential therapeutic treatment for medulloblastoma and glioblastoma.
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Affiliation(s)
- Sarah Ball
- Center for Childhood Cancer, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio, United States of America
- Molecular, Cellular, and Developmental Biology Program, The Ohio State University, Columbus, Ohio, United States of America
| | - Chenglong Li
- Division of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, The Ohio State University, Columbus, Ohio, United States of America
| | - Pui-Kai Li
- Division of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, The Ohio State University, Columbus, Ohio, United States of America
| | - Jiayuh Lin
- Center for Childhood Cancer, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio, United States of America
- Molecular, Cellular, and Developmental Biology Program, The Ohio State University, Columbus, Ohio, United States of America
- * E-mail:
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Noor SM, Bell R, Ward AC. Shooting the messenger: Targeting signal transduction pathways in leukemia and related disorders. Crit Rev Oncol Hematol 2011; 78:33-44. [DOI: 10.1016/j.critrevonc.2010.05.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2009] [Revised: 04/04/2010] [Accepted: 05/05/2010] [Indexed: 01/12/2023] Open
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Choi HG, Ren P, Adrian F, Sun F, Lee HS, Wang X, Ding Q, Zhang G, Xie Y, Zhang J, Liu Y, Tuntland T, Warmuth M, Manley PW, Mestan J, Gray NS, Sim T. A type-II kinase inhibitor capable of inhibiting the T315I "gatekeeper" mutant of Bcr-Abl. J Med Chem 2010; 53:5439-48. [PMID: 20604564 DOI: 10.1021/jm901808w] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The second generation of Bcr-Abl inhibitors nilotinib, dasatinib, and bosutinib developed to override imatinib resistance are not active against the T315I "gatekeeper" mutation. Here we describe a type-II T315I inhibitor 2 (GNF-7), based upon a 3,4-dihydropyrimido[4,5-d]pyrimidin-2(1H)-one scaffold which is capable of potently inhibiting wild-type and T315I Bcr-Abl as well as other clinically relevant Bcr-Abl mutants such as G250E, Q252H, Y253H, E255K, E255V, F317L, and M351T in biochemical and cellular assays. In addition, compound 2 displayed significant in vivo efficacy against T315I-Bcr-Abl without appreciable toxicity in a bioluminescent xenograft mouse model using a transformed T315I-Bcr-Abl-Ba/F3 cell line that has a stable luciferase expression. Compound 2 is among the first type-II inhibitors capable of inhibiting T315I to be described and will serve as a valuable lead to design the third generation Bcr-Abl kinase inhibitors.
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Affiliation(s)
- Hwan Geun Choi
- Dana Farber Cancer Institute, Harvard Medical School, Department of Cancer Biology and Department of Biological Chemistry and Molecular Pharmacology, Boston, Massachusetts 02115, USA
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Oh K, Joo KM, Jung YS, Lee J, Kang H, Lee HY, Lee DS. A receptor-independent, cell-based JAK activation assay for screening for JAK3-specific inhibitors. J Immunol Methods 2010; 354:45-52. [PMID: 20138049 DOI: 10.1016/j.jim.2010.01.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2009] [Revised: 01/22/2010] [Accepted: 01/26/2010] [Indexed: 10/19/2022]
Abstract
New immunosuppressive compounds with less systemic toxicity that could replace calcineurin inhibitors are urgently needed. For identification of specific inhibitors of JAK3, a potential new drug target, from large chemical libraries we developed a cell-based screening system. TEL-JAK fusion proteins composed of an oligomerization domain of TEL and kinase and/or pseudokinase domains of JAKs provided constitutive activation of JAKs without receiving a signal from the cytokine receptors. These fusion proteins also induced STAT5b phosphorylation in the absence of cytokine receptors. Both the kinase and pseudokinase domains of JAKs were required for full activation of the JAKs, and four copies of STAT5 response elements provided the greatest luciferase activity. The sensitivity and specificity of the system was evaluated using specific JAK3, JAK2, or MEK inhibitors. Thus, we generated a receptor-independent, cell-based selective screening system for specific JAK3 inhibitors, which is easily convertible to a high-throughput screening platform.
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Affiliation(s)
- Keunhee Oh
- Laboratory of Immunology, Department of Anatomy, Seoul National University College of Medicine, Republic of Korea
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Cooper S, Giles FJ, Savona MR. Overcoming resistance in chronic myelogenous leukemia. Leuk Lymphoma 2009; 50:1785-93. [DOI: 10.3109/10428190903267559] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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Seo IA, Lee HK, Shin YK, Lee SH, Seo SY, Park JW, Park HT. Janus Kinase 2 Inhibitor AG490 Inhibits the STAT3 Signaling Pathway by Suppressing Protein Translation of gp130. THE KOREAN JOURNAL OF PHYSIOLOGY & PHARMACOLOGY : OFFICIAL JOURNAL OF THE KOREAN PHYSIOLOGICAL SOCIETY AND THE KOREAN SOCIETY OF PHARMACOLOGY 2009; 13:131-8. [PMID: 19885008 DOI: 10.4196/kjpp.2009.13.2.131] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The binding of interleukin-6 (IL-6) cytokine family ligands to the gp130 receptor complex activates the Janus kinase (JAK)/ signal transducer and activator of transcription 3 (STAT3) signal transduction pathway, where STAT3 plays an important role in cell survival and tumorigenesis. Constitutive activation of STAT3 has been frequently observed in many cancer tissues, and thus, blocking of the gp130 signaling pathway, at the JAK level, might be a useful therapeutic approach for the suppression of STAT3 activity, as anticancer therapy. AG490 is a tyrphostin tyrosine kinase inhibitor that has been extensively used for inhibiting JAK2 in vitro and in vivo. In this study, we demonstrate a novel mechanism associated with AG490 that inhibits the JAK/STAT3 pathway. AG490 induced downregulation of gp130, a common receptor for the IL-6 cytokine family compounds, but not JAK2 or STAT3, within three hours of exposure. The downregulation of gp130 was not caused by enhanced degradation of gp130 or by inhibition of mRNA transcription. It most likely occurred by translation inhibition of gp130 in association with phosphorylation of the eukaryotic initiation factor-2alpha . The inhibition of protein synthesis of gp130 by AG490 led to immediate loss of mature gp130 in cell membranes, due to its short half-life, thereby resulting in reduction in the STAT3 response to IL-6. Taken together, these results suggest that AG490 blocks the STAT3 activation pathway via a novel pathway.
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Affiliation(s)
- In Ae Seo
- Department of Physiology, Medical Science Research Institute, College of Medicine, Dong-A University, Busan 602-714, Korea
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Jak2 inhibitors: rationale and role as therapeutic agents in hematologic malignancies. Curr Oncol Rep 2009; 11:117-24. [PMID: 19216843 DOI: 10.1007/s11912-009-0018-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Although the Jak2-V617F mutation has generated strong awareness because of its causative role in myeloproliferative disorders, reports of Jak2 gene aberrations linked to hematologic malignancies have preceded those of V617F by nearly a decade. These malignant mutations include Jak2 amino acid substitutions, deletions, insertions, and chromosomal translocations. As a consequence, researchers are increasingly focused on identifying Jak2 inhibitors that suppress aberrant Jak2 kinase activity. Some of these inhibitors may one day become therapeutically beneficial for individuals with Jak2-related hematologic malignancies. This review summarizes various Jak2 mutations associated with hematologic malignancies and assesses some of the Jak2 inhibitors in the preclinical phase or in clinical trials. By reviewing these specific areas, we hope to have a better understanding of Jak2's role in hematologic malignancies and to shed light on the utility of Jak2 inhibitors.
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Abe M, Funakoshi-Tago M, Tago K, Kamishimoto J, Aizu-Yokota E, Sonoda Y, Kasahara T. The polycythemia vera-associated Jak2 V617F mutant induces tumorigenesis in nude mice. Int Immunopharmacol 2009; 9:870-7. [PMID: 19327411 DOI: 10.1016/j.intimp.2009.03.011] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2008] [Revised: 02/23/2009] [Accepted: 03/18/2009] [Indexed: 10/21/2022]
Abstract
The somatic Jak2 mutation (V617F) was identified in most patients with polycythemia vera (PV). Here, we show that the activating Jak2 V617F mutant completely protected Ba/F3 cells from cytokine withdrawal-induced apoptotic cell death. Interestingly, Ba/F3 cells expressing Jak2 V617F mutant induced rapid tumorigenesis in nude mice, leading to rapid death. Whereas an injection of Ba/F3 cells expressing wild-type Jak2 had no effect, an injection of Ba/F3 cells expressing Jak2 V617F mutant promptly invaded and spread into various distinct organs, such as the liver and spleen. Strikingly, Jak2 inhibitor, AG490 potently inhibited cytokine-independent cell growth induced by the Jak2 V617F mutant. Also, treatment with AG490 effectively delayed Jak2 V617F mutant-induced tumorigenesis in nude mice. Thus, our results both in vitro and in vivo suggest that Jak2 harboring V617F mutation is a potent oncogene able to promote cell transformation and tumorigenesis.
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Affiliation(s)
- Miyuki Abe
- Department of Biochemistry, Faculty of Pharmacology, Keio University, 1-5-30 Shibakoen, Minato-ku, Tokyo 105-8512, Japan
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Zhou LL, Zhao Y, Ringrose A, DeGeer D, Kennah E, Lin AEJ, Sheng G, Li XJ, Turhan A, Jiang X. AHI-1 interacts with BCR-ABL and modulates BCR-ABL transforming activity and imatinib response of CML stem/progenitor cells. ACTA ACUST UNITED AC 2008; 205:2657-71. [PMID: 18936234 PMCID: PMC2571939 DOI: 10.1084/jem.20072316] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Chronic myeloid leukemia (CML) represents the first human malignancy successfully treated with a tyrosine kinase inhibitor (TKI; imatinib). However, early relapses and the emergence of imatinib-resistant disease are problematic. Evidence suggests that imatinib and other inhibitors may not effectively eradicate leukemic stem/progenitor cells, and that combination therapy directed to complimentary targets may improve treatment. Abelson helper integration site 1 (Ahi-1)/AHI-1 is a novel oncogene that is highly deregulated in CML stem/progenitor cells where levels of BCR-ABL transcripts are also elevated. Here, we demonstrate that overexpression of Ahi-1/AHI-1 in murine and human hematopoietic cells confer growth advantages in vitro and induce leukemia in vivo, enhancing effects of BCR-ABL. Conversely, RNAi-mediated suppression of AHI-1 in BCR-ABL–transduced lin−CD34+ human cord blood cells and primary CML stem/progenitor cells reduces their growth autonomy in vitro. Interestingly, coexpression of Ahi-1 in BCR-ABL–inducible cells reverses growth deficiencies exhibited by BCR-ABL down-regulation and is associated with sustained phosphorylation of BCR-ABL and enhanced activation of JAK2–STAT5. Moreover, we identified an AHI-1–BCR-ABL–JAK2 interaction complex and found that modulation of AHI-1 expression regulates phosphorylation of BCR-ABL and JAK2–STAT5 in CML cells. Importantly, this complex mediates TKI response/resistance of CML stem/progenitor cells. These studies implicate AHI-1 as a potential therapeutic target downstream of BCR-ABL in CML.
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Affiliation(s)
- Liang L Zhou
- Terry Fox Laboratory, British Columbia Cancer Agency, Vancouver V5Z 1L3, BC, Canada
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Tao WJ, Lin H, Sun T, Samanta AK, Arlinghaus R. BCR-ABL oncogenic transformation of NIH 3T3 fibroblasts requires the IL-3 receptor. Oncogene 2007; 27:3194-200. [PMID: 18071309 DOI: 10.1038/sj.onc.1210979] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Oncogenic transformation of hematopoietic cells by the Bcr-Abl oncoprotein directly involves the activation Jak2 tyrosine kinase and the Stat5 transcription factor. Both proteins are normally linked to the interleukin (IL)-3/granulocyte-macrophage colony-stimulating factor receptors for growth and survival. Since fibroblastic cells are not targets of BCR-ABL-induced oncogenesis, we determined whether forced expression of the IL-3 receptor would allow oncogenic transformation of NIH 3T3 fibroblasts known to be resistant to transformation by BCR-ABL. NIH 3T3 cells transduced with the human IL-3 receptor alpha and beta chains were highly susceptible to oncogenic transformation by expression of BCR-ABL. Forced expression of both receptor chains but not either one alone allowed efficient foci formation of NIH 3T3 cells expressing BCR-ABL (triple positive cells), and these cells formed colonies in soft agar, whereas BCR-ABL+ NIH 3T3 cells lacking IL-3 receptor expression did not. Signaling studies indicate that the BCR-ABL/IL-3 receptor+ NIH 3T3 cells utilize the Gab2/PI-3 kinase pathway activated by Jak2, and the Stat5 pathway activated separately by Bcr-Abl, whereas BCR-ABL+ NIH 3T3 cells lacking the IL-3 receptor do not utilize the Jak2 pathway, but still maintain activation of Stat5. The Bcr-Abl kinase inhibitor imatinib mesylate (1 microM) and two Jak2 kinase inhibitors strongly inhibited agar colony formation and the activation of Gab2 caused by Jak2. All of these findings indicate that Bcr-Abl oncoprotein requires the IL-3 receptor/Jak2/Stat5 pathways for oncogenic transformation of NIH 3T3 fibroblasts.
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Affiliation(s)
- W J Tao
- Department of Molecular Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX 77054, USA
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Rider L, Shatrova A, Feener EP, Webb L, Diakonova M. JAK2 Tyrosine Kinase Phosphorylates PAK1 and Regulates PAK1 Activity and Functions. J Biol Chem 2007; 282:30985-96. [PMID: 17726028 DOI: 10.1074/jbc.m701794200] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The serine-threonine kinase PAK1 is activated by small GTPase-dependent and -independent mechanisms and promotes cell survival. However, the role of tyrosyl phosphorylation in the regulation of PAK1 function is poorly understood. In this study, we have shown that the prolactin-activated tyrosine kinase JAK2 phosphorylates PAK1 in vivo. Wild type, but not kinase-dead, JAK2 directly phosphorylates PAK1 in cells and in an in vitro kinase assay. PAK1 tyrosines 153, 201, and 285 were identified as sites of JAK2 tyrosyl phosphorylation by mass spectrometry and two-dimensional peptide mapping. Mutation of PAK1 tyrosines 153, 201, and 285 to phenylalanines individually or in combination implicated these PAK1 tyrosines in the regulation of PAK1 kinase activity. Tyrosyl phosphorylation by JAK2 significantly increases PAK1 kinase activity, whereas similar phosphorylation of the PAK1 Y153F,Y201F,Y285F mutant has no effect on PAK1 activity. Tyrosyl phosphorylation of wild type PAK1 decreases apoptosis induced by serum deprivation and staurosporine treatment and increases cell motility. In contrast, these parameters are unaltered in the PAK1 Y153F,Y201F,Y285F mutant. Our findings indicate that JAK2 phosphorylates PAK1 at these specific tyrosines and that this phosphorylation plays an important role in cell survival and motility.
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Affiliation(s)
- Leah Rider
- Department of Biological Sciences, University of Toledo, Toledo, Ohio 43606-3390, USA
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Samanta AK, Lin H, Sun T, Kantarjian H, Arlinghaus RB. Janus kinase 2: a critical target in chronic myelogenous leukemia. Cancer Res 2006; 66:6468-72. [PMID: 16818614 DOI: 10.1158/0008-5472.can-06-0025] [Citation(s) in RCA: 122] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The Bcr-Abl tyrosine kinase is the causative factor in most chronic myelogenous leukemia (CML) patients. We have shown that Bcr-Abl is associated with a cluster of signaling proteins, including Janus kinase (Jak) 2, growth factor receptor binding protein 2-associated binder (Gab) 2, Akt, and glycogen synthase kinase (GSK)-3beta. Treatment of CML cell lines and mouse Bcr-Abl+ 32D cells with either Jak2 short interfering RNA or Jak2 kinase inhibitor AG490 inhibited pTyr Gab2 and pSer Akt formation, inhibited the activation of nuclear factor-kappaB, and caused the activation of GSK-3beta, leading to the reduction of c-Myc. Importantly, BaF3 cells expressing T315I and E255K imatinib-resistant mutants of Bcr-Abl underwent apoptosis on exposure to AG490 yet were resistant to imatinib. Similar to wild-type Bcr-Abl+ cells, inhibition of Jak2 by Ag490 treatment resulted in decrease of pSer Akt and c-Myc in imatinib-resistant cells. These results identify Jak2 as a potentially important therapeutic target for CML.
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MESH Headings
- Animals
- Antineoplastic Agents/pharmacology
- Apoptosis/drug effects
- Benzamides
- Cell Line, Tumor
- Enzyme Activation/drug effects
- Enzyme Inhibitors/pharmacology
- Fusion Proteins, bcr-abl/biosynthesis
- Fusion Proteins, bcr-abl/metabolism
- Glycogen Synthase Kinase 3/metabolism
- Glycogen Synthase Kinase 3 beta
- Humans
- Imatinib Mesylate
- Janus Kinase 2
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/enzymology
- Mice
- NF-kappa B/antagonists & inhibitors
- NF-kappa B/metabolism
- Phosphorylation
- Piperazines/pharmacology
- Protein-Tyrosine Kinases/antagonists & inhibitors
- Protein-Tyrosine Kinases/genetics
- Protein-Tyrosine Kinases/metabolism
- Proto-Oncogene Proteins/antagonists & inhibitors
- Proto-Oncogene Proteins/genetics
- Proto-Oncogene Proteins/metabolism
- Proto-Oncogene Proteins c-akt/antagonists & inhibitors
- Proto-Oncogene Proteins c-akt/metabolism
- Proto-Oncogene Proteins c-myc/biosynthesis
- Pyrimidines/pharmacology
- RNA, Small Interfering/genetics
- Signal Transduction
- Transfection
- Tyrphostins/pharmacology
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Affiliation(s)
- Ajoy K Samanta
- Department of Molecular Pathology, The University of Texas M.D. Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030, USA
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Gu L, Zhuang H, Safina B, Xiao XY, Bradford WW, Rich BE. Combinatorial approach to identification of tyrphostin inhibitors of cytokine signaling. Bioorg Med Chem 2005; 13:4269-78. [PMID: 15869881 DOI: 10.1016/j.bmc.2005.04.022] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2004] [Revised: 04/10/2005] [Accepted: 04/11/2005] [Indexed: 11/28/2022]
Abstract
Aberrant or deregulated activity of certain cellular kinases has been shown to cause certain malignancies and other disorders. The tyrphostin molecule AG490 inhibits the action of the janus kinases JAK2 and JAK3. JAK2 is an indispensable molecule for transducing the signals conveyed by a large number of cytokines including IL-3 while JAK3 is essential for signaling by a smaller number of cytokines including IL-7. A synthetic combinatorial chemical library containing 599 compounds was created and screened for the ability to inhibit proliferation of IL3- and IL7-dependent cell lines to focus on molecules that interrupt those signaling pathways. This screen identified a meta-trifluoromethyl derivative of AG490, 5H4, that is approximately twice as potent as AG490 in cell-based assays. 5H4 blocked the factor-dependent proliferation of both of these cell lines, actively promoted cell death, and diminished the JAK kinase activity. Administration of 5H4 to lymphoma-prone IL-7 transgenic mice reduced their spontaneous lymphadenopathy. The improved characteristics of this novel compound bring this class of molecules closer to therapeutic utility.
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Affiliation(s)
- Ling Gu
- Harvard Skin Disease Research Center, Department of Dermatology, Brigham and Women's Hospital, Boston, MA 02115, USA
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Ahmed-Choudhury J, Williams KT, Young LS, Adams DH, Afford SC. CD40 mediated human cholangiocyte apoptosis requires JAK2 dependent activation of STAT3 in addition to activation of JNK1/2 and ERK1/2. Cell Signal 2005; 18:456-68. [PMID: 15970430 DOI: 10.1016/j.cellsig.2005.05.015] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2004] [Revised: 05/10/2005] [Accepted: 05/17/2005] [Indexed: 12/13/2022]
Abstract
CD40 is critically involved in Fas-mediated cholangiocyte apoptosis during liver inflammation, but the underlying signalling events are poorly understood. Our recent work implicated AP-1 in CD40-induced cholangiocyte apoptosis, but suggested involvement of other signalling pathways. Because STAT3 has been implicated in liver regeneration we investigated this signalling pathway during CD40 mediated cholangiocyte apoptosis. Western immunoblotting, electrophoretic mobility gel shift assays, In situ DNA end labelling and caspase-3 activity were used to investigate intracellular signalling and apoptosis in primary human cholangiocytes following CD40 activation. CD40-activation induced caspase-3 dependent cholangiocyte apoptosis and 3-fold increases in JNK/ERK phosphorylation (concomitant with increased AP-1 binding activity) and 4-fold increases in pSTAT3, which were sustained for up to 24 h. Protein levels of c-Jun, c-Fos and pSTAT3 confirmed the upregulation. Phosphorylation of p38 remained unchanged suggesting that this MAP kinase was not involved in CD40 mediated apoptosis. Increased JAK2 phosphorylation accompanied increased STAT3 phosphorylation after CD40 ligation. Cholangiocytes were also shown to express JAK1 and 3 which was phosphorylated following control stimulation with TNFalpha or IL2 respectively but not after CD40 ligation. JNK, ERK and JAK2 inhibitors partially abrogated apoptosis and when used in combination reduced it to basal levels. In conclusion, induction of CD40-mediated cholangiocyte apoptosis requires JAK2-mediated phosphorylation of STAT3 as well as sustained JNK1/2, ERK1/2 activation. This study demonstrates that STAT3 can function as a proapoptotic factor in primary human liver epithelial cells.
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Affiliation(s)
- Jalal Ahmed-Choudhury
- Liver Research Group, MRC Centre for Immune Regulation, Institute of Biomedical Research, The University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom
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Cousens LP, Goulette FA, Darnowski JW. JAK-mediated signaling inhibits Fas ligand-induced apoptosis independent of de novo protein synthesis. THE JOURNAL OF IMMUNOLOGY 2005; 174:320-7. [PMID: 15611255 DOI: 10.4049/jimmunol.174.1.320] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
There is a growing appreciation for how cells integrate and appropriately respond to competing signals for proliferation and apoptosis. The studies described in this report examined the effects of exposure to the cytokine IFN-alpha (IFN-alpha-2a) on sensitivity of the human cell lines H9 and SKW6.4 to Fas ligand (FasL)-induced apoptosis. In a concentration-dependent manner, FasL induced apoptosis, as shown by Western blot analysis of procaspase 8 and poly(ADP-ribose) polymerase cleavage after 3-h exposure and by cytofluorometric analysis of sub-G(0)-G(1) cellular DNA content after 24-h exposure. H9 and SKW6.4 cell lines responded to 10,000 IU/ml IFN-alpha-2a, as evidenced by decreased cell proliferation and tyrosine phosphorylation of Stat1 and Stat3 proteins without significant cytotoxicity. The effects of cytokine exposure on apoptosis were examined; incubation in medium containing 10,000 IU/ml IFN-alpha-2a for 1 h before FasL treatment significantly reduced all above-mentioned hallmarks of apoptosis. Surprisingly, these antiapoptotic effects of IFN-alpha-2a were independent of de novo protein synthesis, because they occurred in both the absence and the presence of cycloheximide. However, chemical inhibitors of JAK completely abrogated the effects of IFN-alpha-2a on FasL-induced apoptosis, indicating a direct role for JAK-mediated protein phosphorylation in modulating sensitivity to apoptosis. Together, these data suggest a novel mechanism, independent of protein synthesis, by which cytokine signals through JAKs can interact with and attenuate this receptor-mediated apoptotic process.
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Affiliation(s)
- Leslie P Cousens
- Department of Medicine, Division of Medical Oncology, Brown University and Rhode Island Hospital, 593 Eddy Street, Providence, RI 02903, USA.
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40
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Demin P, Rounova O, Grunberger T, Cimpean L, Sharfe N, Roifman CM. Tyrenes: synthesis of new antiproliferative compounds with an extended conjugation. Bioorg Med Chem 2005; 12:3019-26. [PMID: 15142560 DOI: 10.1016/j.bmc.2004.03.043] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2003] [Accepted: 03/12/2004] [Indexed: 11/18/2022]
Abstract
A series of substituted styryl-acrylonitriles was designed and synthesized. The new compounds, called tyrenes, were tested for the ability to inhibit acute lymphocytic leukemia (ALL) cancer cell growth, as well as on their toxicity to normal bone marrow (NBM) cells. The results showed that 3,4-dihydroxystyryl-acrylonitriles, in particular CR-4, revealed great potency as antitumor agents, and also exhibited low toxicity to normal cells. The effectiveness of these compounds with extended conjugation may be due to their possible functioning as reactive Michael acceptors.
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Affiliation(s)
- Peter Demin
- Division of Immunology and Allergy, Infection, Immunity, Injury and Repair Program, Research Institute, and The Hospital for Sick Children and University of Toronto, Toronto, Canada M5G 1X8
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Sternberg DW, Gilliland DG. The Role of Signal Transducer and Activator of Transcription Factors in Leukemogenesis. J Clin Oncol 2004; 22:361-71. [PMID: 14722044 DOI: 10.1200/jco.2004.10.124] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Human leukemias are frequently associated with the aberrant expression of activated fusion tyrosine kinases or activated protein tyrosine kinases carrying insertional or point mutations. The activated kinase enzymes typically phosphorylate one or more signal transducer and activator of transcription (STAT) factors, which translocate to the cell nucleus and regulate the expression of genes associated with survival and proliferation. The phosphorylation and activation of STAT family members has been described in a wide range of human leukemias. Furthermore, animal models of leukemia have demonstrated the pivotal contribution of STAT activation to leukemic pathogenesis. This review discusses evidence for the functional importance of STAT activation in the biology of leukemia and current opportunities for modulating STAT proteins in the therapy of this group of diseases.
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Affiliation(s)
- David W Sternberg
- Hematology Division, Brigham and Women's Hospital, Boston, MA 02115, USA.
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Xie S, Lin H, Sun T, Arlinghaus RB. Jak2 is involved in c-Myc induction by Bcr-Abl. Oncogene 2002; 21:7137-46. [PMID: 12370803 DOI: 10.1038/sj.onc.1205942] [Citation(s) in RCA: 115] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2002] [Revised: 07/31/2002] [Accepted: 08/07/2002] [Indexed: 11/09/2022]
Abstract
We have previously shown that the Jak2 tyrosine kinase is activated in Bcr-Abl positive cell lines and blood cells from CML blast crisis patients by tyrosine phosphorylation. We are searching for downstream targets of Jak2 in Bcr-Abl positive cells. It is known that c-Myc expression is required for the oncogenic effects of Bcr-Abl, and that over-expression of c-Myc complements the transformation defect of the Bcr-Abl SH2 deletion mutant. Moreover, the Bcr-Abl SH2 deletion mutant and an Abl C-terminal deletion mutant are deficient in activating c-Myc expression. Since the Jak2 binds to the C-terminal domain of Bcr-Abl and optimal Jak2 activation requires the SH2 domain, we tested whether Jak2 was involved in c-Myc protein induction by Bcr-Abl. We treated the 32Dp210 Bcr-Abl cells with the Jak2 specific tyrosine kinase inhibitor, AG490, and found that this drug, like the Abl tyrosine kinase inhibitor STI-571, inhibited c-Myc protein induction by Bcr-Abl. Treatment of 32Dp210 Bcr-Abl cells with AG490 also inhibited c-MYC RNA expression. It is also known that c-Myc protein is a labile protein that is increased in amounts in response to various growth factors by a mechanism not involving new Myc protein formation. Treatment of 32Dp210 Bcr-Abl cells with both the proteasome inhibitor MG132 and AG490 blocked the reduction of the c-Myc protein observed by AG490 alone. An adaptor protein SH2-Bbeta is involved in the enhancement of the tyrosine kinase activity of Jak2 following ligand/receptor interaction. In this regard we showed that the Jak2/Bcr-Abl complex contains SH2-Bbeta. Expression of the SH2-Bbeta R555E mutant in 32Dp210 Bcr-Abl cells reduced c-Myc expression about 40% compared to a vector control. Interestingly, we found the reduction of the c-Myc protein in several clones of dominant-negative (DN) Jak2 expressing K562 cells correlated very well with the reduction of tumor growth of these cells in nude mice as compared to vector transfected K562 cells. Both STI-571 and AG490 also induced apoptosis in 32Dp210 cells. Of interest, IL-3 containing medium reversed the STI-571 induced apoptosis of 32Dp210 cells but did not reverse the induction of apoptosis by AG490, which strongly supports the specificity of the inhibitory effects of AG490 on the Jak2 tyrosine kinase. In summary, our findings indicate that Jak2 mediates the increase in c-Myc expression that is induced by Bcr-Abl. Our results indicate that activated Jak2 not only mediates an increase of c-MYC RNA expression but also interferes with proteasome-dependent degradation of c-Myc protein.
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Affiliation(s)
- Shanhai Xie
- Department of Molecular Pathology, The University of Texas M.D. Anderson Cancer Center, 1515 Holcombe Blvd, Houston, Texas, TX 77030, USA
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