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Lu Z, Wang J, Zheng T, Liang Y, Yin D, Song R, Pei T, Pan S, Jiang H, Liu L. FTY720 inhibits proliferation and epithelial-mesenchymal transition in cholangiocarcinoma by inactivating STAT3 signaling. BMC Cancer 2014; 14:783. [PMID: 25344679 PMCID: PMC4221672 DOI: 10.1186/1471-2407-14-783] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2014] [Accepted: 10/17/2014] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND Interleukin 6 (IL-6)-mediated signal transducers and activators of transcription 3 (STAT-3) phosphorylation (activation) is aberrantly sustained in cholangiocarcinoma cells resulting in enhanced myeloid cell leukemia 1 (Mcl-1) expression and resistance to apoptosis. FTY720, a new immunosuppressant, derived from ISP-1, has been studied for its putative anti-cancer properties. This study aimed to elucidate the mechanism by which FTY720 mediates antitumor effects in cholangiocarcinoma (CC) cells. METHODS Three CC cell lines were examined, QBC939, TFK-1, and HuCCT1. The therapeutic effects of FTY720 were evaluated in vitro and in vivo. Cell proliferation, apoptosis, cell cycle, invasive potential, and epithelial- mesenchy-mal transition (EMT) were examined. RESULTS FTY720 greatly inhibited CC cells proliferation and EMT in vitro and in vivo, and this effect was associated with dephosphorylation of STAT3tyr705. FTY720 induced apoptosis and G1 phase arrest in CC cells, and inhibited invasion of CC cells. Western blot analysis showed that FTY720 induced cleavage of caspases 3, 8 and 9, and of PARP, in a dose-dependent manner, consistent with a substantial decrease in p-STAT3, Bcl-xL, Bcl-2, survivin, cyclin D1, cyclin E, N-cadherin, vimentin, VEGF and TWIST1. In vivo studies showed that tumor growth and metastasis were significantly suppressed after FTY720 treatment. CONCLUSIONS These results suggest that FTY720 induces a significant decrease in p-STAT3, which inhibits proliferation and EMT of CC cells, and then induces G1 phase arrest and apoptosis. We have characterized a novel immunosuppressant, which shows potential anti-tumor effects on CC via p-STAT3 inhibition. FTY720 merits further investigation and warrants clinical evaluation.
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Affiliation(s)
- Zhaoyang Lu
- />Department of Hepatic Surgery, The First Affiliated Hospital of Harbin Medical University, Key Laboratory of Hepatosplenic Surgery, Ministry of Education, No. 23 Youzheng Street, Harbin, Heilongjiang Province 150001 China
| | - Jiabei Wang
- />Department of Hepatic Surgery, The First Affiliated Hospital of Harbin Medical University, Key Laboratory of Hepatosplenic Surgery, Ministry of Education, No. 23 Youzheng Street, Harbin, Heilongjiang Province 150001 China
| | - Tongsen Zheng
- />Department of Hepatic Surgery, The First Affiliated Hospital of Harbin Medical University, Key Laboratory of Hepatosplenic Surgery, Ministry of Education, No. 23 Youzheng Street, Harbin, Heilongjiang Province 150001 China
| | - Yingjian Liang
- />Department of Hepatic Surgery, The First Affiliated Hospital of Harbin Medical University, Key Laboratory of Hepatosplenic Surgery, Ministry of Education, No. 23 Youzheng Street, Harbin, Heilongjiang Province 150001 China
| | - Dalong Yin
- />Department of Hepatic Surgery, The First Affiliated Hospital of Harbin Medical University, Key Laboratory of Hepatosplenic Surgery, Ministry of Education, No. 23 Youzheng Street, Harbin, Heilongjiang Province 150001 China
| | - Ruipeng Song
- />Department of Hepatic Surgery, The First Affiliated Hospital of Harbin Medical University, Key Laboratory of Hepatosplenic Surgery, Ministry of Education, No. 23 Youzheng Street, Harbin, Heilongjiang Province 150001 China
| | - Tiemin Pei
- />Department of Hepatic Surgery, The First Affiliated Hospital of Harbin Medical University, Key Laboratory of Hepatosplenic Surgery, Ministry of Education, No. 23 Youzheng Street, Harbin, Heilongjiang Province 150001 China
| | - Shangha Pan
- />Department of Hepatic Surgery, The First Affiliated Hospital of Harbin Medical University, Key Laboratory of Hepatosplenic Surgery, Ministry of Education, No. 23 Youzheng Street, Harbin, Heilongjiang Province 150001 China
| | - Hongchi Jiang
- />Department of Hepatic Surgery, The First Affiliated Hospital of Harbin Medical University, Key Laboratory of Hepatosplenic Surgery, Ministry of Education, No. 23 Youzheng Street, Harbin, Heilongjiang Province 150001 China
| | - Lianxin Liu
- />Department of Hepatic Surgery, The First Affiliated Hospital of Harbin Medical University, Key Laboratory of Hepatosplenic Surgery, Ministry of Education, No. 23 Youzheng Street, Harbin, Heilongjiang Province 150001 China
- />Department of Pharmacology (the State-Province Key Laboratories of Biomedicine-Pharmaceutics of China, Key Laboratory of Cardiovascular Research, Ministry of Education), Harbin Medical University, Harbin, China
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102
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Overexpression of nucleostemin contributes to an advanced malignant phenotype and a poor prognosis in oral squamous cell carcinoma. Br J Cancer 2014; 111:2308-15. [PMID: 25314067 PMCID: PMC4264447 DOI: 10.1038/bjc.2014.539] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Revised: 08/12/2014] [Accepted: 09/16/2014] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND Nucleostemin (NS) is essential for the maintenance of stem cell properties, the functions of which remain poorly understood in cancer cells. The purpose of this study was to explore the impact of NS on malignancy and its clinical significance in oral squamous cell carcinoma (OSCC) patients. METHODS We investigated the effects of NS on the proliferation and invasion of OSCC using NS-overexpressing or -knockdown OSCC cells. We assessed the activation of the STAT3 (signal transducer and activator of transcription 3) signalling pathway and the downstream targets in the cells with different expression levels of NS. An immunohistochemical analysis of NS was also performed in 54 OSCC patients who were treated with preoperative chemoradiotherapy and surgery. RESULTS The overexpression of NS significantly enhanced the proliferation and invasive potential of OSCC cells. On the other hand, downregulation of NS suppressed the invasiveness of the cells. The alterations of these malignant phenotypes were associated with the activation of STAT3 signalling and its downstream targets. An immunohistochemical analysis demonstrated that a high NS tumour expression level significantly correlated with an advanced T-stage and N-stage. Furthermore, a Cox regression analysis revealed that the NS status (hazard ratio, 9.09; P=0.002) was a significant progression factor for OSCC patients. CONCLUSIONS Our results suggest that targeting NS may provide a promising treatment for highly malignant OSCC.
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103
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Breast cancer cells condition lymphatic endothelial cells within pre-metastatic niches to promote metastasis. Nat Commun 2014; 5:4715. [PMID: 25178650 PMCID: PMC4351998 DOI: 10.1038/ncomms5715] [Citation(s) in RCA: 143] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2013] [Accepted: 07/16/2014] [Indexed: 02/07/2023] Open
Abstract
Breast cancer metastasis involves lymphatic dissemination in addition to hematogenous spreading. Although stromal lymphatic vessels (LVs) serve as initial metastatic routes, roles of organ-residing LVs are under-investigated. Here we show that lymphatic endothelial cells (LECs), a component of LVs within pre-metastatic niches, are conditioned by triple-negative breast cancer (TNBC) cells to accelerate metastasis. LECs within the lungs and lymph nodes, conditioned by tumor-secreted factors express CCL5 that is not expressed either in normal LECs or cancer cells, and direct tumor dissemination into these tissues. Moreover, tumor-conditioned LECs promote angiogenesis in these organs, allowing tumor extravasation and colonization. Mechanistically, tumor cell-secreted IL6 causes Stat3 phosphorylation in LECs. This pStat3 induces HIF-1α and VEGF, and a pStat3-pc-Jun-pATF-2 ternary complex induces CCL5 expression in LECs. This study demonstrates anti-metastatic activities of multiple repurposed drugs, blocking a self-reinforcing paracrine loop between breast cancer cells and LECs.
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104
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KIM SANGMIN, JEON MYEONGJIN, LEE JEONGMIN, HAN JEONGHUN, OH SOOJIN, JUNG TAEWOO, NAM SEOKJIN, KIL WONHO, LEE JEONGEON. Induction of fibronectin in response to epidermal growth factor is suppressed by silibinin through the inhibition of STAT3 in triple negative breast cancer cells. Oncol Rep 2014; 32:2230-6. [DOI: 10.3892/or.2014.3450] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2014] [Accepted: 07/02/2014] [Indexed: 11/06/2022] Open
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105
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Kim MJ, Lim J, Yang Y, Lee MS, Lim JS. N-myc downstream-regulated gene 2 (NDRG2) suppresses the epithelial-mesenchymal transition (EMT) in breast cancer cells via STAT3/Snail signaling. Cancer Lett 2014; 354:33-42. [PMID: 25153349 DOI: 10.1016/j.canlet.2014.06.023] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Revised: 05/17/2014] [Accepted: 06/19/2014] [Indexed: 12/31/2022]
Abstract
Although NDRG2 has recently been found to be a candidate tumor suppressor, its precise role in the epithelial-mesenchymal transition (EMT) is not well understood. In the present study, we demonstrated that NDRG2 overexpression in MDA-MB-231 cells down-regulated the expression of Snail, a transcriptional repressor of E-cadherin and a key regulator of EMT, as well as the phosphorylation of signal transducer and activator of transcription 3 (STAT3), an oncogenic transcription factor that is activated in many human malignancies including breast cancer. In addition, we confirmed that the expression of Snail and phospho-STAT3 was recovered when NDRG2 was knocked down by siRNA in MCF7 cells in which NDRG2 is endogenously expressed. Interestingly, MDA-MB-231-NDRG2 cells showed remarkably decreased Snail expression after treatment with JSI-124 (also known as cucurbitacin I) or Stattic, STAT3 inhibitors, compared to MDA-MB-231-mock cells. Moreover, STAT3 activation by EGF treatment induced higher Snail expression, and NDRG2 overexpression resulted in the inhibition of Snail expression in MDA-MB-231 cells stimulated by EGF in the absence or presence of STAT3 inhibitor. Treatment of MDA-MB-231 cells with STAT3 inhibitor led to a moderate decrease in wound healing and migration capacity, whereas STAT3 inhibitor treatment of MDA-MB-231-NDRG2 cells resulted in a significant attenuation of migration in both resting and EGF-stimulated cells. Collectively, our data demonstrate that the inhibition of STAT3 signaling by NDRG2 suppresses EMT progression of EMT via the down-regulation of Snail expression.
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Affiliation(s)
- Myung-Jin Kim
- Department of Biological Science and the Research Center for Women's Diseases, Sookmyung Women's University, Hyochangwongil 52, Yongsan-Gu, Seoul 140-742, Republic of Korea
| | - Jihyun Lim
- Department of Biological Science and the Research Center for Women's Diseases, Sookmyung Women's University, Hyochangwongil 52, Yongsan-Gu, Seoul 140-742, Republic of Korea
| | - Young Yang
- Department of Biological Science and the Research Center for Women's Diseases, Sookmyung Women's University, Hyochangwongil 52, Yongsan-Gu, Seoul 140-742, Republic of Korea
| | - Myeong-Sok Lee
- Department of Biological Science and the Research Center for Women's Diseases, Sookmyung Women's University, Hyochangwongil 52, Yongsan-Gu, Seoul 140-742, Republic of Korea
| | - Jong-Seok Lim
- Department of Biological Science and the Research Center for Women's Diseases, Sookmyung Women's University, Hyochangwongil 52, Yongsan-Gu, Seoul 140-742, Republic of Korea.
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106
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TGF-β1 mediates estrogen receptor-induced epithelial-to-mesenchymal transition in some tumor lines. Tumour Biol 2014; 35:11277-82. [DOI: 10.1007/s13277-014-2166-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2014] [Accepted: 05/27/2014] [Indexed: 02/02/2023] Open
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107
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Davis FM, Stewart TA, Thompson EW, Monteith GR. Targeting EMT in cancer: opportunities for pharmacological intervention. Trends Pharmacol Sci 2014; 35:479-88. [PMID: 25042456 DOI: 10.1016/j.tips.2014.06.006] [Citation(s) in RCA: 240] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2014] [Revised: 06/21/2014] [Accepted: 06/23/2014] [Indexed: 02/09/2023]
Abstract
The spread of cancer cells to distant organs represents a major clinical challenge in the treatment of cancer. Epithelial-mesenchymal transition (EMT) has emerged as a key regulator of metastasis in some cancers by conferring an invasive phenotype. As well as facilitating metastasis, EMT is thought to generate cancer stem cells and contribute to therapy resistance. Therefore, the EMT pathway is of great therapeutic interest in the treatment of cancer and could be targeted either to prevent tumor dissemination in patients at high risk of developing metastatic lesions or to eradicate existing metastatic cancer cells in patients with more advanced disease. In this review, we discuss approaches for the design of EMT-based therapies in cancer, summarize evidence for some of the proposed EMT targets, and review the potential advantages and pitfalls of each approach.
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Affiliation(s)
- Felicity M Davis
- School of Pharmacy, The University of Queensland, Brisbane, QLD, Australia
| | - Teneale A Stewart
- School of Pharmacy, The University of Queensland, Brisbane, QLD, Australia
| | - Erik W Thompson
- St. Vincent's Institute, Fitzroy, VIC, Australia; University of Melbourne Department of Surgery, St Vincent's Hospital, Fitzroy, VIC, Australia; Institute of Health and Biomedical Innovation, Queensland Institute of Technology, Kelvin Grove, QLD, Australia
| | - Gregory R Monteith
- School of Pharmacy, The University of Queensland, Brisbane, QLD, Australia.
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108
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Cross talk between the TM4SF5/focal adhesion kinase and the interleukin-6/STAT3 pathways promotes immune escape of human liver cancer cells. Mol Cell Biol 2014; 34:2946-60. [PMID: 24912675 DOI: 10.1128/mcb.00660-14] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
TM4SF5 overexpressed in hepatocellular carcinoma activates focal adhesion kinase (FAK) during tumor cell migration. However, it remains unknown how TM4SF5 in hepatocellular carcinoma cells compromises with immune actions initiated by extracellular cytokines. Normal and cancerous hepatocytes with or without TM4SF5 expression were analyzed for the effects of cytokine signaling activity on TM4SF5/FAK signaling and metastatic potential. We found that interleukin-6 (IL-6) was differentially expressed in hepatocytes depending on cancerous malignancy and TM4SF5 expression. IL-6 treatment activated FAK and STAT3 and enhanced focal adhesion (FA) formation in TM4SF5-null cells, but it decreased TM4SF5-dependent FAK activity and FA formation in SNU761-TM4SF5 cells. STAT3 suppression abolished the IL-6-mediated effects in normal Chang cells, but it did not recover the TM4SF5-dependent FAK activity that was inhibited by IL-6 treatment in cancerous SNU761-TM4SF5 cells. In addition, modulation of FAK activity did not change the IL-6-mediated STAT3 activity in either the Chang or SNU761 cell system. TM4SF5 expression in SNU761 cells caused invasive extracellular matrix degradation negatively depending on IL-6/IL-6 receptor (IL-6R) signaling. Thus, it is likely that hepatic cancer cells adopt TM4SF5-dependent FAK activation and metastatic potential by lowering IL-6 expression and avoiding its immunological action through the IL-6-STAT3 pathway.
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109
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Wendt MK, Balanis N, Carlin CR, Schiemann WP. STAT3 and epithelial-mesenchymal transitions in carcinomas. JAKSTAT 2014; 3:e28975. [PMID: 24843831 PMCID: PMC4024059 DOI: 10.4161/jkst.28975] [Citation(s) in RCA: 138] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2014] [Revised: 04/21/2014] [Accepted: 04/23/2014] [Indexed: 02/06/2023] Open
Abstract
Cellular programs coupled to cycles of epithelial–mesenchymal transitions (EMTs) play critical roles during embryogenesis, as well as during tissue development, remodeling, and repair. Research over the last decade has established the importance of an ever-expanding list of master EMT transcription factors, whose activity is regulated by STAT3 and function to stimulate the rapid transition of cells between epithelial and mesenchymal phenotypes. Importantly, inappropriate reactivation of embryonic EMT programs in carcinoma cells underlies their metastasis to distant organ sites, as well as their acquisition of stem cell-like and chemoresistant phenotypes operant in eliciting disease recurrence. Thus, targeted inactivation of master EMT transcription factors may offer new inroads to alleviate metastatic disease. Here we review the molecular, cellular, and microenvironmental factors that contribute to the pathophysiological activities of STAT3 during its regulation of EMT programs in human carcinomas.
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Affiliation(s)
- Michael K Wendt
- Department of Medicinal Chemistry and Molecular Pharmacology; Purdue University; West Lafayette, IN USA
| | - Nikolas Balanis
- Department of Physiology and Biophysics; Case Western Reserve University; Cleveland, OH USA
| | - Cathleen R Carlin
- Department of Molecular Biology and Microbiology; Case Western Reserve University; Cleveland, OH USA
| | - William P Schiemann
- Case Comprehensive Cancer Center, Case Western Reserve University; Cleveland, OH USA
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110
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Xie G, Ji A, Yuan Q, Jin Z, Yuan Y, Ren C, Guo Z, Yao Q, Yang K, Lin X, Chen L. Tumour-initiating capacity is independent of epithelial-mesenchymal transition status in breast cancer cell lines. Br J Cancer 2014; 110:2514-23. [PMID: 24755887 PMCID: PMC4021510 DOI: 10.1038/bjc.2014.153] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2013] [Revised: 02/24/2014] [Accepted: 02/26/2014] [Indexed: 12/18/2022] Open
Abstract
Background: Epithelial–mesenchymal transition (EMT) and cancer stem cells (CSCs) are considered to be crucial for cancer biology. The purpose of this study was to determine whether EMT directly led to the acquisition of tumour-initiating capacity in breast cancer cell lines. Methods: Epithelial–mesenchymal transition was induced in five breast cancer cell lines and one normal breast cell line by EMT-related cytokine stimulation. Mesenchymal–epithelial transition (MET) was induced by stably overexpressing miR-200c in three mesenchymal-like breast cancer cell lines. Molecular expression and cell function analysis were performed to evaluate the effect of EMT or MET on tumour-initiating capacity and other biological characteristics. Results: The induction of EMT did not enhance tumour-initiating capacity but, instead, conferred a CD44+/CD24−/low phenotype as well as cell proliferation, migration, and resistance to doxorubicin and radiation on breast cancer cell lines. Furthermore, MET did not lead to inhibition or loss of the tumour-initiating capacity in mesenchymal-like breast cancer cell lines, but it markedly attenuated other malignant properties, including proliferation, invasion, and resistance to therapy. Conclusions: Epithelial–mesenchymal transition does not alter tumour-initiating capacity of breast cancer cells but some other biological characteristics. Therefore, EMT and tumour-initiating capacity may not be directly linked in breast cancer cell lines.
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Affiliation(s)
- G Xie
- Department of Radiation Oncology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong 510515, PR China
| | - A Ji
- Department of Pharmaceutical Science, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong 510282, PR China
| | - Q Yuan
- Jules Stein Eye Institute, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA
| | - Z Jin
- Department of Pharmacy, Jining First People's Hospital, Jining, Shandong 272111, PR China
| | - Y Yuan
- Department of Radiation Oncology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong 510515, PR China
| | - C Ren
- Department of Radiation Oncology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong 510515, PR China
| | - Z Guo
- Breast Center, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong 510515, PR China
| | - Q Yao
- Department of Radiation Oncology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong 510515, PR China
| | - K Yang
- Department of Neurosurgery, Institute of Neurosurgery, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong 510515, PR China
| | - X Lin
- Department of Radiation Oncology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong 510515, PR China
| | - L Chen
- Department of Radiation Oncology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong 510515, PR China
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111
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HiJAK'd Signaling; the STAT3 Paradox in Senescence and Cancer Progression. Cancers (Basel) 2014; 6:741-55. [PMID: 24675570 PMCID: PMC4074801 DOI: 10.3390/cancers6020741] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2014] [Revised: 03/08/2014] [Accepted: 03/11/2014] [Indexed: 12/11/2022] Open
Abstract
Clinical and epidemiological data have associated chronic inflammation with cancer progression. Most tumors show evidence of infiltrating immune and inflammatory cells, and chronic inflammatory disorders are known to increase the overall risk of cancer development. While immune cells are often observed in early hyperplastic lesions in vivo, there remains debate over whether these immune cells and the cytokines they produce in the developing hyperplastic microenvironment act to inhibit or facilitate tumor development. The interleukin-6 (IL-6) family of cytokines, which includes IL-6 and oncostatin M (OSM), among others (LIF, CT-1, CNTF, and CLC), are secreted by immune cells, stromal cells, and epithelial cells, and regulate diverse biological processes. Each of the IL-6 family cytokines signals through a distinct receptor complex, yet each receptor complex uses a shared gp130 subunit, which is critical for signal transduction following cytokine binding. Activation of gp130 results in the activation of Signal Transducer and Activator of Transcription 3 (STAT3), and the Mitogen-Activated Protein Kinase (MAPK) and Phosphatidylinositol 3-Kinase (PI3K) signaling cascades. Tumor suppressive signaling can often be observed in normal cells following prolonged STAT3 activation. However, there is mounting evidence that the IL-6 family cytokines can contribute to later stages of tumor progression in many ways. Here we will review how the microenvironmental IL-6 family cytokine OSM influences each stage of the transformation process. We discuss the intrinsic adaptations a developing cancer cell must make in order to tolerate and circumvent OSM-mediated growth suppression, as well as the OSM effectors that are hijacked during tumor expansion and metastasis. We propose that combining current therapies with new ones that suppress the signals generated from the tumor microenvironment will significantly impact an oncologist’s ability to treat cancer.
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