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Abstract
STAT3 plays a central role in oncogenesis by mediating cell survival, growth, and differentiation. It is constitutively activated in breast cancer. We investigated the role of STAT3 in tumor development by knocking down STAT3 levels in MDA-MB-231 triple negative breast cancer cells using short hairpin RNA. The tumor forming potential of these STAT3-depleted cells was assessed by xenografts in immunocompromised NOD SCID mice. Contrary to its accepted tumor promoting role, we found STAT3 to be a negative regulator of growth in MDA-MB-231- derived tumors. Although similar observations have been made in thyroid carcinoma and lung adenocarcinoma xenograft studies, our novel results showed for the first time that the role of STAT3 in promoting tumorigenesis may be context-specific, and that STAT3 may actually be a negative regulator of certain breast-cancer types. Studies to identify the mechanisms of STAT3's negative regulatory role may be useful in developing STAT3-based therapeutics.
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Affiliation(s)
- Kasturi Banerjee
- The Gene and Linda Voiland School of Chemical Engineering and Bioengineering, Washington State University, Pullman, WA, USA
| | - Cindy Pru
- Department of Animal Sciences, Center for Reproductive Biology, Washington State University, Pullman, WA, USA
| | - James K Pru
- Department of Animal Sciences, Center for Reproductive Biology, Washington State University, Pullman, WA, USA
| | - Haluk Resat
- The Gene and Linda Voiland School of Chemical Engineering and Bioengineering, Washington State University, Pullman, WA, USA
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Galoczova M, Coates P, Vojtesek B. STAT3, stem cells, cancer stem cells and p63. Cell Mol Biol Lett 2018; 23:12. [PMID: 29588647 PMCID: PMC5863838 DOI: 10.1186/s11658-018-0078-0] [Citation(s) in RCA: 165] [Impact Index Per Article: 27.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Accepted: 03/07/2018] [Indexed: 12/15/2022] Open
Abstract
Signal Transducer and Activator of Transcription 3 (STAT3) is a transcription factor with many important functions in the biology of normal and transformed cells. Its regulation is highly complex as it is involved in signaling pathways in many different cell types and under a wide variety of conditions. Besides other functions, STAT3 is an important regulator of normal stem cells and cancer stem cells. p63 which is a member of the p53 protein family is also involved in these functions and is both physically and functionally connected with STAT3. This review summarizes STAT3 function and regulation, its role in stem cell and cancer stem cell properties and highlights recent reports about its relationship to p63.
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Affiliation(s)
- Michaela Galoczova
- Regional Centre for Applied Molecular Oncology, Masaryk Memorial Cancer Institute, Zluty kopec 7, 656 53 Brno, Czech Republic
| | - Philip Coates
- Regional Centre for Applied Molecular Oncology, Masaryk Memorial Cancer Institute, Zluty kopec 7, 656 53 Brno, Czech Republic
| | - Borivoj Vojtesek
- Regional Centre for Applied Molecular Oncology, Masaryk Memorial Cancer Institute, Zluty kopec 7, 656 53 Brno, Czech Republic
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53
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Natural small molecule bigelovin suppresses orthotopic colorectal tumor growth and inhibits colorectal cancer metastasis via IL6/STAT3 pathway. Biochem Pharmacol 2018; 150:191-201. [PMID: 29454618 DOI: 10.1016/j.bcp.2018.02.017] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Accepted: 02/14/2018] [Indexed: 01/12/2023]
Abstract
Bigelovin, a sesquiterpene lactone, has been demonstrated to induce apoptosis, inhibit inflammation and angiogenesis in vitro, but its potential anti-metastatic activity remains unclear. In the present study, two colon cancer mouse models, orthotopic tumor allografts and experimental metastatic models were utilized to investigate the progression and metastatic spread of colorectal cancer after bigelovin treatments. Results showed that bigelovin (intravenous injection; 0.3-3 mg/kg) significantly suppressed tumor growth and inhibited liver/lung metastasis with modulation of tumor microenvironment (e.g. increased populations of T lymphocytes and macrophages) in orthotopic colon tumor allograft-bearing mice. Furthermore, the inhibitory activities were also validated in the experimental human colon cancer metastatic mouse model. The underlying mechanisms involved in the anti-metastatic effects of bigelovin were then revealed in murine colon tumor cells colon 26-M01 and human colon cancer cells HCT116. Results showed that bigelovin induced cytotoxicity, inhibition of cell proliferation, motility and migration in both cell lines, which were through interfering IL6/STAT3 and cofilin pathways. Alternations of the key molecules including Rock, FAK, RhoA, Rac1/2/3 and N-cadherin, which were detected in bigelovin-treated cancer cells, were also observed in the tumor allografts of bigelovin-treated mice. These findings strongly indicated that bigelovin has potential to be developed as anti-tumor and anti-metastatic agent for colorectal cancer.
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54
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Liu Y, Gibson SA, Benveniste EN, Qin H. Opportunities for Translation from the Bench: Therapeutic Intervention of the JAK/STAT Pathway in Neuroinflammatory Diseases. Crit Rev Immunol 2018; 35:505-27. [PMID: 27279046 DOI: 10.1615/critrevimmunol.2016015517] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Pathogenic CD4+ T cells and myeloid cells play critical roles in the pathogenesis of multiple sclerosis (MS) and experimental autoimmune encephalomyelitis (EAE), an animal model of MS. These immune cells secrete aberrantly high levels of pro-inflammatory cytokines that pathogenically bridge the innate and adaptive immune systems and damage neurons and oligodendrocytes. These cytokines include interleukin-2 (IL-2), IL-6, IL-12, IL-21, IL-23, granulocyte macrophage-colony stimulating factor (GM-CSF), and interferon-γ (IFN-γ). It is, therefore, not surprising that both the dysregulated expression of these cytokines and the subsequent activation of their downstream signaling cascades is a common feature in MS/EAE. The Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway is utilized by numerous cytokines for signal transduction and is essential for the development and regulation of immune responses. Unbridled activation of the JAK/STAT pathway by pro-inflammatory cytokines has been demonstrated to be critically involved in the pathogenesis of MS/EAE. In this review, we discuss recent advancements in our understanding of the involvement of the JAK/STAT signaling pathway in the pathogenesis of MS/EAE, with a particular focus on therapeutic approaches to target the JAK/STAT pathway.
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Affiliation(s)
- Yudong Liu
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama, 35294; Systemic Autoimmunity Branch, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD 20892
| | - Sara A Gibson
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama, 35294
| | - Etty N Benveniste
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama, 35294
| | - Hongwei Qin
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama, 35294
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55
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Ebrahimiyan H, Aslani S, Rezaei N, Jamshidi A, Mahmoudi M. Survivin and autoimmunity; the ins and outs. Immunol Lett 2018; 193:14-24. [DOI: 10.1016/j.imlet.2017.11.004] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2017] [Revised: 09/13/2017] [Accepted: 11/06/2017] [Indexed: 02/06/2023]
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Arumuggam N, Melong N, Too CKL, Berman JN, Rupasinghe HPV. Phloridzin docosahexaenoate, a novel flavonoid derivative, suppresses growth and induces apoptosis in T-cell acute lymphoblastic leukemia cells. Am J Cancer Res 2017; 7:2452-2464. [PMID: 29312799 PMCID: PMC5752686] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Accepted: 08/02/2017] [Indexed: 06/07/2023] Open
Abstract
The overall clinical outcome in T-cell acute lymphoblastic leukemia (T-ALL) can be improved by minimizing risk for treatment failure using effective pharmacological adjuvants. Phloridzin (PZ), a flavonoid precursor found in apple peels, was acylated with docosahexaenoic acid (DHA) yielding a novel ester known as phloridzin docosahexaenoate (PZ-DHA). Here, we have studied the cytotoxic effects of PZ-DHA on human leukemia cells using in vitro and in vivo models. The inhibitory effects of PZ-DHA were tested on human Jurkat T-ALL cells in comparison to K562 chronic myeloid leukemia (CML) cells and non-malignant murine T-cells. PZ-DHA, not PZ or DHA alone, reduced cell viability and ATP levels, increased intracellular LDH release, and caused extensive morphological alterations in both Jurkat and K562 cells. PZ-DHA also inhibited cell proliferation, and selectively induced apoptosis in Jurkat and K562 cells while sparing normal murine T-cells. The cytotoxic effects of PZ-DHA on Jurkat cells were associated with caspase activation, DNA fragmentation, and selective down-regulation of STAT3 phosphorylation. PZ-DHA significantly inhibited Jurkat cell proliferation in zebrafish larvae; however, the proliferation of K562 cells was not affected in vivo. We propose that PZ-DHA-induced cytotoxic response is selective towards T-ALL in the presence of a tumor-stromal microenvironment. Prospective studies evaluating the combinatorial effects of PZ-DHA with conventional chemotherapy for T-ALL are underway.
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Affiliation(s)
- Niroshaathevi Arumuggam
- Department of Plant, Food, & Environmental Sciences, Faculty of Agriculture, Dalhousie UniversityTruro, NS B2N 5E3, Canada
| | | | - Catherine KL Too
- Department of Biochemistry & Molecular Biology, Dalhousie University, Faculty of MedicineHalifax, NS B3H 4R2, Canada
| | - Jason N Berman
- IWK Health CentreHalifax, NS B3K 6R8, Canada
- Department of Pediatrics, Dalhousie University, Faculty of MedicineHalifax, NS B3H 4R2, Canada
- Department of Pathology, Dalhousie University, Faculty of MedicineHalifax, NS B3H 4R2, Canada
| | - HP Vasantha Rupasinghe
- Department of Plant, Food, & Environmental Sciences, Faculty of Agriculture, Dalhousie UniversityTruro, NS B2N 5E3, Canada
- Department of Pathology, Dalhousie University, Faculty of MedicineHalifax, NS B3H 4R2, Canada
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57
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Kanna R, Choudhary G, Ramachandra N, Steidl U, Verma A, Shastri A. STAT3 inhibition as a therapeutic strategy for leukemia. Leuk Lymphoma 2017; 59:2068-2074. [PMID: 29164994 DOI: 10.1080/10428194.2017.1397668] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Leukemia is characterized by selective overgrowth of malignant hematopoietic stem cells (HSC's) that interfere with HSC differentiation. Cytoreductive chemotherapy can kill rapidly dividing cancerous cells but cannot eradicate the malignant HSC pool leading to relapses. Leukemic stem cells have several dysregulated pathways and the Janus kinases (JAKs) and signal transducer and activator of transcription (STAT) pathway are prominent among them. STAT3 is an important transcription factor that regulates cell growth, proliferation, and inhibits apoptosis. High STAT3 expression in leukemia has been associated with an increased risk for relapse and decreased overall survival. Multiple strategies for interfering with STAT3 activity in leukemic cells include inhibition of STAT3 phosphorylation, interfering with STAT3 interactions, preventing nuclear transfer, inhibiting transcription and causing interference in STAT: DNA binding. A better understanding of key interactions and upstream mediators of STAT3 activity will help facilitate the development of effective cancer therapies and may result in durable remissions.
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Affiliation(s)
- Rubashruti Kanna
- a Division of Hematologic Malignancies, Department of Oncology, Albert Einstein College of Medicine , Bronx , NY , USA
| | - Gaurav Choudhary
- a Division of Hematologic Malignancies, Department of Oncology, Albert Einstein College of Medicine , Bronx , NY , USA
| | - Nandini Ramachandra
- a Division of Hematologic Malignancies, Department of Oncology, Albert Einstein College of Medicine , Bronx , NY , USA
| | - Ulrich Steidl
- a Division of Hematologic Malignancies, Department of Oncology, Albert Einstein College of Medicine , Bronx , NY , USA
| | - Amit Verma
- a Division of Hematologic Malignancies, Department of Oncology, Albert Einstein College of Medicine , Bronx , NY , USA
| | - Aditi Shastri
- a Division of Hematologic Malignancies, Department of Oncology, Albert Einstein College of Medicine , Bronx , NY , USA
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58
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Activation of STAT3 integrates common profibrotic pathways to promote fibroblast activation and tissue fibrosis. Nat Commun 2017; 8:1130. [PMID: 29066712 PMCID: PMC5654983 DOI: 10.1038/s41467-017-01236-6] [Citation(s) in RCA: 237] [Impact Index Per Article: 33.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Accepted: 08/29/2017] [Indexed: 12/18/2022] Open
Abstract
Signal transducer and activator of transcription 3 (STAT3) is phosphorylated by various kinases, several of which have been implicated in aberrant fibroblast activation in fibrotic diseases including systemic sclerosis (SSc). Here we show that profibrotic signals converge on STAT3 and that STAT3 may be an important molecular checkpoint for tissue fibrosis. STAT3 signaling is hyperactivated in SSc in a TGFβ-dependent manner. Expression profiling and functional studies in vitro and in vivo demonstrate that STAT3 activation is mediated by the combined action of JAK, SRC, c-ABL, and JNK kinases. STAT3-deficient fibroblasts are less sensitive to the pro-fibrotic effects of TGFβ. Fibroblast-specific knockout of STAT3, or its pharmacological inhibition, ameliorate skin fibrosis in experimental mouse models. STAT3 thus integrates several profibrotic signals and might be a core mediator of fibrosis. Considering that several STAT3 inhibitors are currently tested in clinical trials, STAT3 might be a candidate for molecular targeted therapies of SSc. STAT3 is a transcription factor that is activated in fibrotic diseases such as systemic sclerosis. Here the authors show that STAT3 is the converging point for multiple pro-fibrotic signalling pathways, and that its genetic ablation or inhibition ameliorate skin fibrosis in mouse models.
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59
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Cocchiola R, Romaniello D, Grillo C, Altieri F, Liberti M, Magliocca FM, Chichiarelli S, Marrocco I, Borgoni G, Perugia G, Eufemi M. Analysis of STAT3 post-translational modifications (PTMs) in human prostate cancer with different Gleason Score. Oncotarget 2017; 8:42560-42570. [PMID: 28489571 PMCID: PMC5522088 DOI: 10.18632/oncotarget.17245] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Accepted: 04/05/2017] [Indexed: 01/09/2023] Open
Abstract
Prostate Cancer (PCa) is a complex and heterogeneous disease. The androgen receptor (AR) and the signal transducer and activator of transcription 3 (STAT3) could be effective targets for PCa therapy. STAT3, a cytoplasmatic latent transcription factor, is a hub protein for several oncogenic signalling pathways and up-regulates the expression of numerous genes involved in tumor cell proliferation, angiogenesis, metastasis and cell survival. STAT3 activity can be modulated by several Post-Translational Modifications (PTMs) which reflect particular cell conditions and may be implicated in PCa development and progression. The aim of this work was to analyze STAT3 PTMs at different tumor stages and their relationship with STAT3 cellular functions. For this purpose, sixty-five prostatectomy, Formalin-fixed paraffin-embedded (FFPE) specimens, classified with different Gleason Scores, were subjected to immunoblotting, immunofluorescence staining and RT-PCR analysis. All experiments were carried out in matched non-neoplastic and neoplastic tissues. Data obtained showed different STAT3 PTMs profiles among the analyzed tumor grades which correlate with differences in the amount and distribution of specific STAT3 interactors as well as the expression of STAT3 target genes. These results highlight the importance of PTMs as an additional biomarker for the exactly evaluation of the PCa stage and the optimal treatment of this disease.
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Affiliation(s)
- Rossana Cocchiola
- Department of Biochemical Sciences, Sapienza University of Rome, Rome, Italy
- Istituto Pasteur, Fondazione Cenci Bolognetti, Piazzale Aldo Moro 5, Rome, Italy
- Fondazione Enrico ed Enrica Sovena, Rome, Italy
| | - Donatella Romaniello
- Department of Biochemical Sciences, Sapienza University of Rome, Rome, Italy
- Istituto Pasteur, Fondazione Cenci Bolognetti, Piazzale Aldo Moro 5, Rome, Italy
| | - Caterina Grillo
- Department of Biochemical Sciences, Sapienza University of Rome, Rome, Italy
- Istituto Pasteur, Fondazione Cenci Bolognetti, Piazzale Aldo Moro 5, Rome, Italy
| | - Fabio Altieri
- Department of Biochemical Sciences, Sapienza University of Rome, Rome, Italy
- Istituto Pasteur, Fondazione Cenci Bolognetti, Piazzale Aldo Moro 5, Rome, Italy
| | - Marcello Liberti
- Department of Gynecological-Obstretic Science and Urologic Sciences, Sapienza University of Rome, Rome, Italy
| | - Fabio Massimo Magliocca
- Department of Radiological, Oncological and Pathological Sciences, Sapienza University of Rome, Rome, Italy
| | - Silvia Chichiarelli
- Department of Biochemical Sciences, Sapienza University of Rome, Rome, Italy
- Istituto Pasteur, Fondazione Cenci Bolognetti, Piazzale Aldo Moro 5, Rome, Italy
| | - Ilaria Marrocco
- Department of Biochemical Sciences, Sapienza University of Rome, Rome, Italy
- Istituto Pasteur, Fondazione Cenci Bolognetti, Piazzale Aldo Moro 5, Rome, Italy
| | - Giuseppe Borgoni
- Department of Gynecological-Obstretic Science and Urologic Sciences, Sapienza University of Rome, Rome, Italy
| | - Giacomo Perugia
- Department of Gynecological-Obstretic Science and Urologic Sciences, Sapienza University of Rome, Rome, Italy
| | - Margherita Eufemi
- Department of Biochemical Sciences, Sapienza University of Rome, Rome, Italy
- Istituto Pasteur, Fondazione Cenci Bolognetti, Piazzale Aldo Moro 5, Rome, Italy
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60
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Tuberatolide B Suppresses Cancer Progression by Promoting ROS-Mediated Inhibition of STAT3 Signaling. Mar Drugs 2017; 15:md15030055. [PMID: 28245605 PMCID: PMC5367012 DOI: 10.3390/md15030055] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2016] [Revised: 02/06/2017] [Accepted: 02/17/2017] [Indexed: 02/06/2023] Open
Abstract
Tuberatolide B (TTB, C27H34O4) is a diastereomeric meroterpenoid isolated from the Korean marine algae Sargassum macrocarpum. However, the anticancer effects of TTB remain unknown. In this study, we demonstrate that TTB inhibits tumor growth in breast, lung, colon, prostate, and cervical cancer cells. To examine the mechanism by which TTB suppresses cell growth, we determined the effect of TTB on apoptosis, ROS generation, DNA damage, and signal transduction. TTB induced ROS production in MDA-MB-231, A549, and HCT116 cells. Moreover, TTB enhanced DNA damage by inducing γH2AX foci formation and the phosphorylation of DNA damage-related proteins such as Chk2 and H2AX. Furthermore, TTB selectively inhibited STAT3 activation, which resulted in a reduction in cyclin D1, MMP-9, survivin, VEGF, and IL-6. In addition, TTB-induced ROS generation caused STAT3 inhibition, DNA damage, and apoptotic cell death. Therefore, TTB suppresses cancer progression by promoting ROS-mediated inhibition of STAT3 signaling, suggesting that TTB is useful for the treatment of cancer.
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61
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Nakamura K, Smyth MJ. Targeting cancer-related inflammation in the era of immunotherapy. Immunol Cell Biol 2017; 95:325-332. [PMID: 27999432 DOI: 10.1038/icb.2016.126] [Citation(s) in RCA: 120] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Revised: 11/24/2016] [Accepted: 11/26/2016] [Indexed: 02/07/2023]
Abstract
Recent advances in cancer immunotherapy, particularly immune checkpoint blockade therapy have dramatically changed the therapeutic strategy against advanced malignancies. Still, only a subset of patients shows a good response to any single therapy. Moreover, it remains largely unsolved how we can maintain durable clinical responses, or how we can successfully treat a broader range of cancers by immunotherapy. Growing evidence suggests that the major barrier to more successful cancer immunotherapy is the tumour microenvironment (TME), where chronic inflammation has a predominant role in tumour survival and proliferation, angiogenesis and immunosuppression. Over the past decades, our understanding of cancer-related inflammation has significantly evolved, and now we have various therapeutic options tailored to the TME. These therapeutic strategies include inhibiting inflammatory mediators or their downstream signalling molecules, blocking the recruitment of myeloid cells, modulating immunosuppressive functions in myeloid cells and re-educating the TME. In this review, we discuss the role of cancer-related inflammation as a potential target in the era of immunotherapy.
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Affiliation(s)
- Kyohei Nakamura
- Immunology in Cancer and Infection Laboratory, QIMR Berghofer Medical, Research Institute, Herston, QLD, Australia
| | - Mark J Smyth
- Immunology in Cancer and Infection Laboratory, QIMR Berghofer Medical, Research Institute, Herston, QLD, Australia.,School of Medicine, University of Queensland, Herston, QLD, Australia
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62
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Todoric J, Antonucci L, Karin M. Targeting Inflammation in Cancer Prevention and Therapy. Cancer Prev Res (Phila) 2016; 9:895-905. [PMID: 27913448 DOI: 10.1158/1940-6207.capr-16-0209] [Citation(s) in RCA: 252] [Impact Index Per Article: 31.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Accepted: 10/03/2016] [Indexed: 12/14/2022]
Abstract
Inflammation is associated with the development and malignant progression of most cancers. As most of the cell types involved in cancer-associated inflammation are genetically stable and thus are not subjected to rapid emergence of drug resistance, the targeting of inflammation represents an attractive strategy both for cancer prevention and for cancer therapy. Tumor-extrinsic inflammation is caused by many factors, including bacterial and viral infections, autoimmune diseases, obesity, tobacco smoking, asbestos exposure, and excessive alcohol consumption, all of which increase cancer risk and stimulate malignant progression. In contrast, cancer-intrinsic or cancer-elicited inflammation can be triggered by cancer-initiating mutations and can contribute to malignant progression through the recruitment and activation of inflammatory cells. Both extrinsic and intrinsic inflammation can result in immunosuppression, thereby providing a preferred background for tumor development. In clinical trials, lifestyle modifications including healthy diet, exercise, alcohol, and smoking cessation have proven effective in ameliorating inflammation and reducing the risk of cancer-related deaths. In addition, consumption of certain anti-inflammatory drugs, including aspirin, can significantly reduce cancer risk, suggesting that common nonsteroidal anti-inflammatory drugs (NSAID) and more specific COX2 inhibitors can be used in cancer prevention. In addition to being examined for their preventative potential, both NSAIDs and more potent anti-inflammatory antibody-based drugs need to be tested for their ability to augment the efficacy of more conventional therapeutic approaches on the basis of tumor resection, radiation, and cytotoxic chemicals. Cancer Prev Res; 9(12); 895-905. ©2016 AACR.
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Affiliation(s)
- Jelena Todoric
- Laboratory of Gene Regulation and Signal Transduction, Department of Pharmacology, School of Medicine, University of California San Diego, La Jolla, California.,Department of Laboratory Medicine, Medical University of Vienna, Vienna, Austria
| | - Laura Antonucci
- Laboratory of Gene Regulation and Signal Transduction, Department of Pharmacology, School of Medicine, University of California San Diego, La Jolla, California
| | - Michael Karin
- Laboratory of Gene Regulation and Signal Transduction, Department of Pharmacology, School of Medicine, University of California San Diego, La Jolla, California. .,Department of Pathology, School of Medicine, University of California San Diego, La Jolla, California
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63
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Yoo JY, Jeong JW, Fazleabas AT, Tayade C, Young SL, Lessey BA. Protein Inhibitor of Activated STAT3 (PIAS3) Is Down-Regulated in Eutopic Endometrium of Women with Endometriosis. Biol Reprod 2016; 95:11. [PMID: 27226311 PMCID: PMC5029430 DOI: 10.1095/biolreprod.115.137158] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Accepted: 05/09/2016] [Indexed: 01/07/2023] Open
Abstract
Endometriosis is a major cause of chronic pelvic pain and infertility. Activation of STAT3 appears central to the inflammatory phenotype of eutopic endometrium in women with endometriosis. However, the molecular mechanism by which this occurs remains unknown. Our objective is to determine how STAT3 activity is regulated in endometriosis. Protein inhibitor of activated STAT3 (PIAS3) is a negative regulator of STAT3 activity. We examined the levels of PIAS3 in endometrium from women with and without endometriosis using Western blot analysis and immunohistochemistry. Levels of PIAS3 are significantly lower, in contrast with phosphorylation of STAT3, in women with endometriosis compared to women without endometriosis. Furthermore, induction of endometriosis in the baboon showed a significant reduction of PIAS3 expression during the progression of the disease. Interferon-γ (INFγ) reduces PIAS3 protein levels and increases phospho-STAT3 levels through CXCL10 in endometrial cells, Ishikawa, and 12Z cells. These results suggest that attenuation of PIAS3 causes aberrant activation of STAT3 in endometriosis, leading to inflammatory changes that may impair fertility or cause pain.
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Affiliation(s)
- Jung-Yoon Yoo
- Department of Obstetrics, Gynecology & Reproductive Biology, Michigan State University, Grand Rapids, Michigan
| | - Jae-Wook Jeong
- Department of Obstetrics, Gynecology & Reproductive Biology, Michigan State University, Grand Rapids, Michigan
| | - Asgerally T Fazleabas
- Department of Obstetrics, Gynecology & Reproductive Biology, Michigan State University, Grand Rapids, Michigan
| | - Chandrakant Tayade
- Department of Obstetrics and Gynecology, Queens University, Kingston, Canada
| | - Steven L Young
- Department of Obstetrics and Gynecology, University of North Carolina, Chapel Hill, North Carolina
| | - Bruce A Lessey
- Department of Obstetrics and Gynecology, University of South Carolina School of Medicine, Greenville Health System, Greenville, South Carolina
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Martincuks A, Fahrenkamp D, Haan S, Herrmann A, Küster A, Müller-Newen G. Dissecting functions of the N-terminal domain and GAS-site recognition in STAT3 nuclear trafficking. Cell Signal 2016; 28:810-25. [PMID: 27040695 DOI: 10.1016/j.cellsig.2016.03.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Revised: 02/11/2016] [Accepted: 03/23/2016] [Indexed: 12/25/2022]
Abstract
Signal transducer and activator of transcription 3 (STAT3) is a ubiquitous transcription factor involved in many biological processes, including hematopoiesis, inflammation and cancer progression. Cytokine-induced gene transcription greatly depends on tyrosine phosphorylation of STAT3 on a single tyrosine residue with subsequent nuclear accumulation and specific DNA sequence (GAS) recognition. In this study, we analyzed the roles of the conserved STAT3 N-terminal domain (NTD) and GAS-element binding ability of STAT3 in nucleocytoplasmic trafficking. Our results demonstrate the nonessential role of GAS-element recognition for both cytokine-induced and basal nuclear import of STAT3. Substitution of five key amino acids within the DNA-binding domain rendered STAT3 unable to bind to GAS-elements while still maintaining the ability for nuclear localization. In turn, deletion of the NTD markedly decreased nuclear accumulation upon IL-6 treatment resulting in a prolonged accumulation of phosphorylated dimers in the cytoplasm, at the same time preserving specific DNA recognition ability of the truncation mutant. Observed defect in nuclear localization could not be explained by flawed importin-α binding, since both wild-type and NTD deletion mutant of STAT3 could precipitate both full-length and autoinhibitory domain (∆IBB) deletion mutants of importin-α5, as well as ∆IBB-α3 and ∆IBB-α7 isoforms independently of IL-6 stimulation. Despite its inability to translocate to the nucleus upon IL-6 stimulation, the NTD lacking mutant still showed nuclear accumulation in resting cells similar to wild-type upon inhibition of nuclear export by leptomycin B. At the same time, blocking the nuclear export pathway could not rescue cytoplasmic trapping of phosphorylated STAT3 molecules without NTD. Moreover, STAT3 mutant with dysfunctional SH2 domain (R609Q) also localized in the nucleus of unstimulated cells after nuclear export blocking, while upon cytokine treatment the subcellular localization of this mutant had not changed. Our findings support the concept that basal nucleocytoplasmic shuttling of STAT3 is different from active cytokine-induced nuclear import and does not require conserved N- or SH2-terminal domains, preformed dimer formation and GAS-element-specific DNA recognition.
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Affiliation(s)
- Antons Martincuks
- Institute of Biochemistry and Molecular Biology, Faculty of Medicine, RWTH Aachen University, Pauwelsstraße 30, 52074 Aachen, Germany
| | - Dirk Fahrenkamp
- Institute of Biochemistry and Molecular Biology, Faculty of Medicine, RWTH Aachen University, Pauwelsstraße 30, 52074 Aachen, Germany
| | - Serge Haan
- Institute of Biochemistry and Molecular Biology, Faculty of Medicine, RWTH Aachen University, Pauwelsstraße 30, 52074 Aachen, Germany; Molecular Disease Mechanisms Group, Life Sciences Research Unit, University of Luxembourg, 162A Avenue de la Faïencerie, L-1511, Luxembourg, Luxembourg; Signal Transduction Group, Life Sciences Research Unit, University of Luxembourg, 162A Avenue de la Faïencerie, L-1511, Luxembourg, Luxembourg
| | - Andreas Herrmann
- Institute of Biochemistry and Molecular Biology, Faculty of Medicine, RWTH Aachen University, Pauwelsstraße 30, 52074 Aachen, Germany; Beckman Research Institute, City of Hope National Medical Center, Duarte, CA, USA
| | - Andrea Küster
- Institute of Biochemistry and Molecular Biology, Faculty of Medicine, RWTH Aachen University, Pauwelsstraße 30, 52074 Aachen, Germany
| | - Gerhard Müller-Newen
- Institute of Biochemistry and Molecular Biology, Faculty of Medicine, RWTH Aachen University, Pauwelsstraße 30, 52074 Aachen, Germany.
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Tang Y, Guo Q, Zhi Y, Jin X, Xia B, Guo S, Tian C, Zhang Y. [Role of CXCR4/STAT3 in mesenchymal stromal cell-mediated drug resistance of acute leukemia cells]. ZHONGHUA XUE YE XUE ZA ZHI = ZHONGHUA XUEYEXUE ZAZHI 2016; 37:119-23. [PMID: 27014981 PMCID: PMC7348206 DOI: 10.3760/cma.j.issn.0253-2727.2016.02.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Indexed: 11/29/2022]
Abstract
OBJECTIVE To explore the role of CXCR4/STAT3 in mesenchymal stromal cell (MSC)-mediated drug resistance of AML cells. METHODS AML cell lines U937 and KG1a and primary AML cells were co-cultured with MSC from bone marrow of healthy donors. The AML cell lines cultured alone were used as control. Apoptosis induced by mitoxantrone was measured by flow cytometry. Expression of CXCR4 and STAT3 protein were detected by Western blot. After incubated with STAT3 inhibitor Cucurbitacin I or CXCR4 antagonist AMD3100, the apoptosis of AML cells induced by mitoxantrone was evaluated. RESULTS Apoptosis of AML cells (U937 and KG1a) and primary AML cells induced by mitoxantrone significantly decreased in cocultured group than that of control group [U937 cells: (20.08±1.53)% vs (45.33 ± 1.03)% , P=0.004; KG1a cells: (25.60 ± 1.82)% vs (40.33 ± 3.29)% , P=0.020]. Expression of phosphorylated STAT3 and CXCR4 protein in AML cells were upregulated in cocultured group. After addition of Cucurbitacin I into the co-culture system, the apoptosis rate of primary AML cells significantly increased. Similar results of the apoptosis rates were also detected when the inhibitor of CXCR4 AMD3100 was added to overcome the stromal cell-mediated drug resistance. Besides, the expression of p-STAT3 in AML cells after incubated with AMD3100 decreased significantly. CONCLUSIONS AML cells cocultured with MSC leads to the up-regulation of phosphorylated STAT3 and CXCR4 proteins, which resulted in AML cells resistance to chemotherapeutic drugs. Therefore targeting STAT3 or CXCR4 could be a new therapeutic strategy of AML.
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Affiliation(s)
- Yungjun Tang
- Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center For Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin 300060, China
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Serum-resistant CpG-STAT3 decoy for targeting survival and immune checkpoint signaling in acute myeloid leukemia. Blood 2016; 127:1687-700. [PMID: 26796361 DOI: 10.1182/blood-2015-08-665604] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Accepted: 01/16/2016] [Indexed: 02/08/2023] Open
Abstract
Targeting oncogenic transcription factor signal transducer and activator of transcription 3 (STAT3) in acute myeloid leukemia (AML) can reduce blast survival and tumor immune evasion. Decoy oligodeoxynucleotides (dODNs), which comprise STAT3-specific DNA sequences are competitive inhibition of STAT3 transcriptional activity. To deliver STAT3dODN specifically to myeloid cells, we linked STAT3dODN to the Toll-like receptor 9 (TLR9) ligand, cytosine guanine dinucleotide (CpG). The CpG-STAT3dODN conjugates are quickly internalized by human and mouse TLR9(+)immune cells (dendritic cells, B cells) and the majority of patients' derived AML blasts, including leukemia stem/progenitor cells. Following uptake, CpG-STAT3dODNs are released from endosomes, and bind and sequester cytoplasmic STAT3, thereby inhibiting downstream gene expression in target cells. STAT3 inhibition in patients' AML cells limits their immunosuppressive potential by reduced arginase expression, thereby partly restoring T-cell proliferation. Partly chemically modified CpG-STAT3dODNs have >60 hours serum half-life which allows for IV administration to leukemia-bearing mice (50% effective dose ∼ 2.5 mg/kg). Repeated administration of CpG-STAT3dODN resulted in regression of human MV4-11 AML in mice. The antitumor efficacy of this strategy is further enhanced in immunocompetent mice by combining direct leukemia-specific cytotoxicity with immunogenic effects of STAT3 blocking/TLR9 triggering. CpG-STAT3dODN effectively reducedCbfb/MYH11/MplAML burden in various organs and eliminated leukemia stem/progenitor cells, mainly through CD8/CD4 T-cell-mediated immune responses. In contrast, small-molecule Janus kinase 2/STAT3 inhibitor failed to reproduce therapeutic effects of cell-selective CpG-STAT3dODN strategy. These results demonstrate therapeutic potential of CpG-STAT3dODN inhibitors with broad implications for treatment of AML and potentially other hematologic malignancies.
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Yeh JE, Frank DA. STAT3-Interacting Proteins as Modulators of Transcription Factor Function: Implications to Targeted Cancer Therapy. ChemMedChem 2015; 11:795-801. [DOI: 10.1002/cmdc.201500482] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2015] [Revised: 12/01/2015] [Indexed: 12/14/2022]
Affiliation(s)
- Jennifer E. Yeh
- Department of Medical Oncology; Dana-Farber Cancer Institute; 450 Brookline Avenue Boston MA 02215 USA
| | - David A. Frank
- Department of Medical Oncology; Dana-Farber Cancer Institute; 450 Brookline Avenue Boston MA 02215 USA
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Klinke DJ, Birtwistle MR. In silico model-based inference: an emerging approach for inverse problems in engineering better medicines. Curr Opin Chem Eng 2015; 10:14-24. [PMID: 26309811 PMCID: PMC4545575 DOI: 10.1016/j.coche.2015.07.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Identifying the network of biochemical interactions that underpin disease pathophysiology is a key hurdle in drug discovery. While many components involved in these biological processes are identified, how components organize differently in health and disease remains unclear. In chemical engineering, mechanistic modeling provides a quantitative framework to capture our understanding of a reactive system and test this knowledge against data. Here, we describe an emerging approach to test this knowledge against data that leverages concepts from probability, Bayesian statistics, and chemical kinetics by focusing on two related inverse problems. The first problem is to identify the causal structure of the reaction network, given uncertainty as to how the reactive components interact. The second problem is to identify the values of the model parameters, when a network is known a priori.
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Affiliation(s)
- David J. Klinke
- Department of Chemical Engineering and Mary Babb Randolph Cancer Center, West Virginia University, Morgantown, WV
- Department of Microbiology, Immunology, & Cell Biology, West Virginia University, Morgantown, WV
| | - Marc R. Birtwistle
- Department of Pharmacology and Systems Therapeutics, Icahn School of Medicine at Mount Sinai, New York, NY
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Sharma M, Zhou J, Gauchat JF, Sharma R, McCarthy ET, Srivastava T, Savin VJ. Janus kinase 2/signal transducer and activator of transcription 3 inhibitors attenuate the effect of cardiotrophin-like cytokine factor 1 and human focal segmental glomerulosclerosis serum on glomerular filtration barrier. Transl Res 2015; 166:384-98. [PMID: 25843671 PMCID: PMC4569535 DOI: 10.1016/j.trsl.2015.03.002] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Revised: 03/04/2015] [Accepted: 03/10/2015] [Indexed: 12/31/2022]
Abstract
Recurrence of idiopathic focal segmental glomerulosclerosis (FSGS) after renal transplantation is believed to be caused by a circulating factor(s). We detected cardiotrophin-like cytokine factor 1 (CLCF1), a member of the interleukin 6 family, in the plasma from patients with recurrent FSGS. We hypothesized that CLCF1 contributes to the effect of FSGS serum on the glomerular filtration barrier in vitro. Presently, we studied the effect of CLCF1 on isolated rat glomeruli using an in vitro assay of albumin permeability (P(alb)). CLCF1 (0.05-100 ng/mL) increased P(alb) and caused maximal effect at 5-10 ng/mL (P < 0.001). The increase in Palb was analogous to the effect of FSGS serum. Anti-CLCF1 monoclonal antibody blocked the CLCF1-induced increase in P(alb) and significantly attenuated the effect of FSGS serum (P < 0.001). The heterodimer composed of CLCF1 and cosecreted molecule cytokine receptor-like factor 1 (CRLF1) attenuated the increase in P(alb) caused by CLCF1 or FSGS serum. Western blot analysis showed that CLCF1 upregulated phosphorylation of signal transducer and activator of transcription 3 (STAT3) (Tyr705) in glomeruli. This effect was diminished by the heterodimer CLCF1-CRLF1. Janus kinase 2 (JAK2) inhibitor BMS-1119543 or STAT3 inhibitor Stattic significantly blocked the effect of CLCF1 or FSGS serum on P(alb) (P < 0.001). These novel findings suggest that when monomeric CLCF1 increases P(alb), the heterodimer CLCF1-CRLF1 may protect the glomerular filtration barrier. We speculate that albuminuria in FSGS is related to qualitative or quantitative changes in the CLCF1-CRLF1 complex, and that JAK2 or STAT3 inhibitors may be novel therapeutic agents to treat FSGS.
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Affiliation(s)
- Mukut Sharma
- Renal Research Laboratory, Research and Development, MBRF and Kansas City VA Medical Center, Kansas City, Mo; Kidney Institute, University of Kansas Medical Center, Kansas City, Kan.
| | - Jianping Zhou
- Renal Research Laboratory, Research and Development, MBRF and Kansas City VA Medical Center, Kansas City, Mo
| | | | - Ram Sharma
- Renal Research Laboratory, Research and Development, MBRF and Kansas City VA Medical Center, Kansas City, Mo
| | - Ellen T McCarthy
- Kidney Institute, University of Kansas Medical Center, Kansas City, Kan
| | - Tarak Srivastava
- Renal Research Laboratory, Research and Development, MBRF and Kansas City VA Medical Center, Kansas City, Mo; Section of Nephrology, Children's Mercy Hospital and University of Missouri at Kansas City, Kansas City, Mo
| | - Virginia J Savin
- Renal Research Laboratory, Research and Development, MBRF and Kansas City VA Medical Center, Kansas City, Mo; Kidney Institute, University of Kansas Medical Center, Kansas City, Kan
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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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Development and characterization of conducting polymer nanoparticles for photodynamic therapy in vitro. Photodiagnosis Photodyn Ther 2015; 12:476-89. [DOI: 10.1016/j.pdpdt.2015.04.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2015] [Revised: 04/27/2015] [Accepted: 04/29/2015] [Indexed: 12/13/2022]
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Sammak S, Zinzalla G. Targeting protein-protein interactions (PPIs) of transcription factors: Challenges of intrinsically disordered proteins (IDPs) and regions (IDRs). PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2015; 119:41-6. [PMID: 26126425 DOI: 10.1016/j.pbiomolbio.2015.06.004] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2015] [Revised: 06/23/2015] [Accepted: 06/25/2015] [Indexed: 12/26/2022]
Abstract
In this review we discuss recent progress in targeting the protein-protein interactions made by oncogenic transcription factors. We particularly focus on the challenges posed by the prevalence of intrinsically disordered regions in this class of protein and the strategies being used to overcome them.
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Affiliation(s)
- Susan Sammak
- Department of Microbiology, Cell and Tumour Biology, and Science for Life Laboratory, Karolinska Institutet, Tomtebodavägen 23A, Stockholm 171 65, Sweden
| | - Giovanna Zinzalla
- Department of Microbiology, Cell and Tumour Biology, and Science for Life Laboratory, Karolinska Institutet, Tomtebodavägen 23A, Stockholm 171 65, Sweden.
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Maenhout SK, Du Four S, Corthals J, Neyns B, Thielemans K, Aerts JL. AZD1480 delays tumor growth in a melanoma model while enhancing the suppressive activity of myeloid-derived suppressor cells. Oncotarget 2015; 5:6801-15. [PMID: 25149535 PMCID: PMC4196164 DOI: 10.18632/oncotarget.2254] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
AZD1480 is a potent, competitive small-molecule inhibitor of JAK1/2 kinase which inhibits STAT3 phosphorylation and tumor growth. Here we investigated the effects of AZD1480 on the function of different immune cell populations in a melanoma model. When MO4 tumor-bearing mice were treated with AZD1480 we observed a strong inhibition of tumor growth as well as a prolonged survival. Moreover, a significant decrease in the percentage of myeloid-derived suppressor cells (MDSCs) was observed after treatment with AZD1480. However, AZD1480 enhanced the suppressive capacity of murine MDSCs while at the same time impairing the proliferative as well as the IFN-γ secretion capacity of murine T cells. The addition of AZD1480 to co-cultures of human MDSCs and T cells does not affect the suppressive activity of MDSCs but it does reduce the IFN-γ secretion and the proliferative capacity of T cells. We showed that although AZD1480 has the ability to delay the tumor growth of MO4 tumor-bearing mice, this drug has detrimental effects on several aspects of the immune system. These data indicate that systemic targeting of the JAK/STAT pathway by JAK1/2 inhibition can have divergent effects on tumor growth and anti-tumor immune responses.
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Affiliation(s)
- Sarah K Maenhout
- Laboratory of Molecular and Cellular Therapy, Department of Immunology-Physiology, Vrije Universiteit Brussel, Brussels, Belgium
| | - Stephanie Du Four
- Laboratory of Molecular and Cellular Therapy, Department of Immunology-Physiology, Vrije Universiteit Brussel, Brussels, Belgium. Department of Medical Oncology, Universiteit Ziekenhuis Brussel, Brussels, Belgium
| | - Jurgen Corthals
- Laboratory of Molecular and Cellular Therapy, Department of Immunology-Physiology, Vrije Universiteit Brussel, Brussels, Belgium
| | - Bart Neyns
- Laboratory of Molecular and Cellular Therapy, Department of Immunology-Physiology, Vrije Universiteit Brussel, Brussels, Belgium. Department of Medical Oncology, Universiteit Ziekenhuis Brussel, Brussels, Belgium
| | - Kris Thielemans
- Laboratory of Molecular and Cellular Therapy, Department of Immunology-Physiology, Vrije Universiteit Brussel, Brussels, Belgium
| | - Joeri L Aerts
- Laboratory of Molecular and Cellular Therapy, Department of Immunology-Physiology, Vrije Universiteit Brussel, Brussels, Belgium
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Silibinin and STAT3: A natural way of targeting transcription factors for cancer therapy. Cancer Treat Rev 2015; 41:540-6. [PMID: 25944486 DOI: 10.1016/j.ctrv.2015.04.008] [Citation(s) in RCA: 100] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2014] [Revised: 04/19/2015] [Accepted: 04/20/2015] [Indexed: 12/11/2022]
Abstract
Signal transducer and activator of transcription 3 (STAT3) is constitutively activated in many different types of cancer and plays a pivotal role in tumor growth and metastasis. Retrospective studies have established that STAT3 expression or phospho-STAT3 (pSTAT3 or activated STAT3) are poor prognostic markers for breast, colon, prostate and non-small cell lung cancer. Silibinin or silybin is a natural polyphenolic flavonoid which is present in seed extracts of milk thistle (Silybum marianum). Silibinin has been shown to inhibit multiple cancer cell signaling pathways in preclinical models, demonstrating promising anticancer effects in vitro and in vivo. This review summarizes evidence suggesting that silibinin can inhibit pSTAT3 in preclinical cancer models. We also discuss current strategies to overcome the limitations of oral administration of silibinin to cancer patients to translate the bench results to the bed side. Finally, we review the ongoing clinical trials exploring the role of silibinin in cancer.
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Mukherjee A, Khuda-Bukhsh AR. Quercetin Down-regulates IL-6/STAT-3 Signals to Induce Mitochondrial-mediated Apoptosis in a Nonsmall- cell Lung-cancer Cell Line, A549. J Pharmacopuncture 2015; 18:19-26. [PMID: 25830055 PMCID: PMC4379472 DOI: 10.3831/kpi.2015.18.002] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2014] [Revised: 12/11/2014] [Accepted: 12/11/2014] [Indexed: 12/22/2022] Open
Abstract
Objectives: Quercetin, a flavonoid compound, has been reported to induce apoptosis in cancer cells, but its anti-inflammatory effects, which are also closely linked with apoptosis, if any, on non-small-cell lung cancer (NSCLC) have not so far been critically examined. In this study, we tried to determine if quercetin had any demonstrable anti-inflammatory potential, which also could significantly contribute to inducing apoptosis in a NSCLC cell line, A549. Methods: In this context, several assays, including cytotoxicity, flow cytometry and fluorimetry, were done. Gene expression was analyzed by using a western blot analysis. Results: Results revealed that quercetin could induce apoptosis in A549 cells through mitochondrial depolarization by causing an imbalance in B-cell lymphoma 2/ Bcl2 Antagonist X (Bcl2/Bax) ratio and by down-regulating the interleukine-6/signal transducer and activator of transcription 3 (IL-6/STAT3) signaling pathway. An analysis of the data revealed that quercetin could block nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) activity at early hours, which might cause a down-regulation of the IL-6 titer, and the IL-6 expression, in turn, could inhibit p-STAT3 expression. Down-regulation of both the STAT3 and the NF-κB expressions might, therefore, cause down-regulation of Bcl2 activity because both are major upstream effectors of Bcl2. Alteration in Bcl2 responses might result in an imbalance in the Bcl2/Bax ratio, which could ultimately bring about mitochondria mediated apoptosis in A549 cells. Conclusion: Overall, the finding of this study indicates that a quercetin induced anti-inflammatory pathway in A549 cells appeared to make a significant contribution towards induction of apoptosis in NSCLC and, thus, may have a therapeutic use such as a strong apoptosis inducer in cancer cells.
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Affiliation(s)
- Avinaba Mukherjee
- Cytogenetics and Molecular Biology Laboratory, Department of Zoology, University of Kalyani, Kalyani, India
| | - Anisur Rahman Khuda-Bukhsh
- Cytogenetics and Molecular Biology Laboratory, Department of Zoology, University of Kalyani, Kalyani, India
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Kim BG, Yoo JY, Kim TH, Shin JH, Langenheim JF, Ferguson SD, Fazleabas AT, Young SL, Lessey BA, Jeong JW. Aberrant activation of signal transducer and activator of transcription-3 (STAT3) signaling in endometriosis. Hum Reprod 2015; 30:1069-78. [PMID: 25750101 DOI: 10.1093/humrep/dev050] [Citation(s) in RCA: 79] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2014] [Accepted: 02/12/2015] [Indexed: 12/25/2022] Open
Abstract
STUDY QUESTION Are STAT3 signaling molecules differentially expressed in endometriosis? SUMMARY ANSWER Levels of phospho-STAT3 and HIF1A, its downstream signaling molecule, are significantly higher in eutopic endometrium from women with endometriosis when compared with women without the disease. WHAT IS KNOWN ALREADY Endometriosis is an estrogen-dependent inflammatory condition. Interleukin 6 (IL-6) is an inflammatory survival cytokine known to induce prolonged activation of STAT3 via association with the IL-6 receptor. STUDY DESIGN, SIZE, DURATION Cross-sectional measurements of STAT3 and HIF1A protein levels in eutopic endometrium from women with endometriosis versus those without. PARTICIPANTS/MATERIALS, SETTING, METHODS Levels of phospho-STAT3 (pSTAT3) and HIF1A were examined in the endometrium of patients with and without endometriosis as well as in a non-human primate animal model using western blot and immunohistochemical analysis. MAIN RESULTS AND THE ROLE OF CHANCE Levels of pSTAT3 were significantly higher in the eutopic endometrium from women with endometriosis when compared with women without the disease in both the proliferative and secretory phases. HIF1A is known to be stabilized by STAT3 and IL-6. Our immunohistochemistry results show abundant HIF1A expression within the eutopic endometrial epithelial cells of women with endometriosis. Furthermore, pSTAT3 and HIF1A proteins are co-localized in endometriosis. This aberrant activation of pSTAT3 and HIF1A is confirmed by sequential analysis of eutopic endometrium using a baboon animal model of induced endometriosis. Lastly, we confirmed this IL-6 induction of both STAT3 phosphorylation and HIF1A mRNA expression in Ishikawa human endometrial adenocarcinoma cell line. LIMITATIONS, REASONS FOR CAUTION Ishikawa cancer cell line was used to study a benign disease. The peritoneal fluid contains various inflammatory cytokines in addition to IL-6 and so it is possible that other cytokines may affect the activity and expression of STAT3 signaling molecules. WIDER IMPLICATIONS OF THE FINDINGS Our results imply that aberrant activation of STAT3 signaling plays an important role in the pathogenesis of endometriosis. Our findings could progress in our understanding of the etiology and pathophysiology of endometriosis and potential therapeutic interventions by targeted pharmacological. STUDY FUNDING/COMPETING INTERESTS This work was supported by NIH R01 HD067721 (to S.L.Y and B.A.L) and NIH R01 HD057873 and American Cancer Society Research Grant RSG-12-084-01-TBG (to J.-W.J.). There are no conflicts of interest.
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Affiliation(s)
- Byung Gak Kim
- Obstetrics, Gynecology & Reproductive Biology, Michigan State University, Grand Rapids, MI 49503, USA
| | - Jung-Yoon Yoo
- Obstetrics, Gynecology & Reproductive Biology, Michigan State University, Grand Rapids, MI 49503, USA
| | - Tae Hoon Kim
- Obstetrics, Gynecology & Reproductive Biology, Michigan State University, Grand Rapids, MI 49503, USA
| | - Jung-Ho Shin
- Division of Reproductive Endocrinology, Department of Obstetrics & Gynecology, Guro Hospital, Korea University Medical Center, Seoul 152-703, South Korea
| | - John F Langenheim
- Obstetrics and Gynecology, University Medical Group, Greenville Health System, Greenville, SC 29605, USA
| | - Susan D Ferguson
- Obstetrics, Gynecology & Reproductive Biology, Michigan State University, Grand Rapids, MI 49503, USA
| | - Asgerally T Fazleabas
- Obstetrics, Gynecology & Reproductive Biology, Michigan State University, Grand Rapids, MI 49503, USA Department of Women's Health, Spectrum Health System, Grand Rapids, MI 49341, USA
| | - Steven L Young
- Obstetrics and Gynecology, University of North Carolina, Chapel Hill, NC 27514, USA
| | - Bruce A Lessey
- Obstetrics and Gynecology, University Medical Group, Greenville Health System, Greenville, SC 29605, USA
| | - Jae-Wook Jeong
- Obstetrics, Gynecology & Reproductive Biology, Michigan State University, Grand Rapids, MI 49503, USA Department of Women's Health, Spectrum Health System, Grand Rapids, MI 49341, USA
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Bruserud Ø, Reikvam H, Fredly H, Skavland J, Hagen KM, van Hoang TT, Brenner AK, Kadi A, Astori A, Gjertsen BT, Pendino F. Expression of the potential therapeutic target CXXC5 in primary acute myeloid leukemia cells - high expression is associated with adverse prognosis as well as altered intracellular signaling and transcriptional regulation. Oncotarget 2015; 6:2794-811. [PMID: 25605239 PMCID: PMC4413618 DOI: 10.18632/oncotarget.3056] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2014] [Accepted: 12/21/2014] [Indexed: 12/24/2022] Open
Abstract
The CXXC5 gene encodes a transcriptional activator with a zinc-finger domain, and high expression in human acute myeloid leukemia (AML) cells is associated with adverse prognosis. We now characterized the biological context of CXXC5 expression in primary human AML cells. The global gene expression profile of AML cells derived from 48 consecutive patients was analyzed; cells with high and low CXXC5 expression then showed major differences with regard to extracellular communication and intracellular signaling. We observed significant differences in the phosphorylation status of several intracellular signaling mediators (CREB, PDK1, SRC, STAT1, p38, STAT3, rpS6) that are important for PI3K-Akt-mTOR signaling and/or transcriptional regulation. High CXXC5 expression was also associated with high mRNA expression of several stem cell-associated transcriptional regulators, the strongest associations being with WT1, GATA2, RUNX1, LYL1, DNMT3, SPI1, and MYB. Finally, CXXC5 knockdown in human AML cell lines caused significantly increased expression of the potential tumor suppressor gene TSC22 and genes encoding the growth factor receptor KIT, the cytokine Angiopoietin 1 and the selenium-containing glycoprotein Selenoprotein P. Thus, high CXXC5 expression seems to affect several steps in human leukemogenesis, including intracellular events as well as extracellular communication.
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MESH Headings
- Adult
- Aged
- Aged, 80 and over
- Biomarkers, Tumor/genetics
- Biomarkers, Tumor/metabolism
- Carrier Proteins/genetics
- Carrier Proteins/metabolism
- Cell Line, Tumor
- DNA-Binding Proteins
- Female
- Gene Expression Profiling
- Gene Expression Regulation, Leukemic
- Humans
- Leukemia, Myeloid, Acute/genetics
- Leukemia, Myeloid, Acute/metabolism
- Male
- Middle Aged
- Phosphorylation
- Primary Cell Culture
- Prognosis
- RNA Interference
- RNA, Messenger/metabolism
- Signal Transduction
- Transcription Factors
- Transcription, Genetic
- Transfection
- Tumor Cells, Cultured
- Up-Regulation
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Affiliation(s)
- Øystein Bruserud
- Section for Hematology, Department of Clinical Science, University of Bergen, Norway
- Department of Medicine, Haukeland University Hospital, Bergen, Norway
| | - Håkon Reikvam
- Section for Hematology, Department of Clinical Science, University of Bergen, Norway
- Department of Medicine, Haukeland University Hospital, Bergen, Norway
| | - Hanne Fredly
- Section for Hematology, Department of Clinical Science, University of Bergen, Norway
- Department of Medicine, Haukeland University Hospital, Bergen, Norway
| | - Jørn Skavland
- Department of Medicine, Haukeland University Hospital, Bergen, Norway
| | - Karen-Marie Hagen
- Section for Hematology, Department of Clinical Science, University of Bergen, Norway
| | - Tuyen Thy van Hoang
- Section for Hematology, Department of Clinical Science, University of Bergen, Norway
| | - Annette K. Brenner
- Section for Hematology, Department of Clinical Science, University of Bergen, Norway
| | - Amir Kadi
- Inserm, U1016, Institut Cochin, F-75014, Paris, France
- CNRS, UMR8104, F-75014, Paris, France
- Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Audrey Astori
- Inserm, U1016, Institut Cochin, F-75014, Paris, France
- CNRS, UMR8104, F-75014, Paris, France
- Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Bjørn Tore Gjertsen
- Section for Hematology, Department of Clinical Science, University of Bergen, Norway
- Department of Medicine, Haukeland University Hospital, Bergen, Norway
| | - Frederic Pendino
- Department of Molecular Biology, University of Bergen, Bergen, Norway
- Inserm, U1016, Institut Cochin, F-75014, Paris, France
- CNRS, UMR8104, F-75014, Paris, France
- Université Paris Descartes, Sorbonne Paris Cité, Paris, France
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Dutta P, Sabri N, Li J, Li WX. Role of STAT3 in lung cancer. JAKSTAT 2015; 3:e999503. [PMID: 26413424 DOI: 10.1080/21623996.2014.999503] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2014] [Revised: 12/10/2014] [Accepted: 12/15/2014] [Indexed: 12/18/2022] Open
Abstract
Lung cancer remains a challenging disease. It is responsible for the high cancer mortality rates in the US and worldwide. Elucidation of the molecular mechanisms operative in lung cancer is an important first step in developing effective therapies. Accumulating evidence over the last 2 decades suggests a critical role for Signal Transducer and Activator of Transcription 3 (STAT3) as a point of convergence for various signaling pathways that are dysregulated in the disease. In this review, we discuss possible molecular mechanisms involving STAT3 in lung tumorigenesis based on recent literature. We consider possible roles of STAT3 in cancer cell proliferation and survival, in the tumor immune environment, and in epigenetic regulation and interaction of STAT3 with other transcription factors. We also discuss the potential role of STAT3 in tumor suppression, which complicates strategies of targeting STAT3 in cancer therapy.
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Affiliation(s)
- Pranabananda Dutta
- Department of Medicine; University of California, San Diego ; La Jolla, CA USA
| | - Nafiseh Sabri
- Department of Medicine; University of California, San Diego ; La Jolla, CA USA ; Department of Chemistry & Molecular Biology; University of Gothenburg ; Gothenburg, Sweden
| | - Jinghong Li
- Department of Medicine; University of California, San Diego ; La Jolla, CA USA
| | - Willis X Li
- Department of Medicine; University of California, San Diego ; La Jolla, CA USA
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79
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Bruserud Ø, Nepstad I, Hauge M, Hatfield KJ, Reikvam H. STAT3 as a possible therapeutic target in human malignancies: lessons from acute myeloid leukemia. Expert Rev Hematol 2014; 8:29-41. [PMID: 25374305 DOI: 10.1586/17474086.2015.971005] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
STAT3 is important for transcriptional regulation in human acute myeloid leukemia (AML). STAT3 has thousands of potential DNA binding sites but usually shows cell type specific binding preferences to a limited number of these. Furthermore, AML is a very heterogeneous disease, and studies of the prognostic impact of STAT3 in human AML have also given conflicting results. A more detailed characterization of STAT3 functions and the expression of various isoforms in human AML will therefore be required before it is possible to design clinical studies of STAT3 inhibitors in this disease, and it will be especially important to investigate whether the functions of STAT3 differ between patients. Several other malignancies also show extensive biological heterogeneity, and the present discussion and the suggested scientific approaches may thus be relevant for other cancer patients.
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Affiliation(s)
- Øystein Bruserud
- Department of Medicine, Haukeland University Hospital, Bergen, Norway
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80
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von Manstein V, Yang CM, Richter D, Delis N, Vafaizadeh V, Groner B. Resistance of Cancer Cells to Targeted Therapies Through the Activation of Compensating Signaling Loops. ACTA ACUST UNITED AC 2014; 8:193-202. [PMID: 25045345 PMCID: PMC4095943 DOI: 10.2174/1574362409666140206221931] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2013] [Revised: 01/21/2014] [Accepted: 01/29/2014] [Indexed: 01/05/2023]
Abstract
The emergence of low molecular weight kinase inhibitors as “targeted” drugs has led to remarkable advances in the treatment of cancer patients. The clinical benefits of these tumor therapies, however, vary widely in patient populations and with duration of treatment. Intrinsic and acquired resistance against such drugs limits their efficacy. In addition to the well studied mechanisms of resistance based upon drug transport and metabolism, genetic alterations in drug target structures and the activation of compensatory cell signaling have received recent attention. Adaptive responses can be triggered which counteract the initial dependence of tumor cells upon a particular signaling molecule and allow only a transient inhibition of tumor cell growth. These compensating signaling mechanisms are often based upon the relief of repression of regulatory feedback loops. They might involve cell autonomous, intracellular events or they can be mediated via the secretion of growth factor receptor ligands into the tumor microenvironment and signal induction in an auto- or paracrine fashion. The transcription factors Stat3 and Stat5 mediate the biological functions of cytokines, interleukins and growth factors and can be considered as endpoints of multiple signaling pathways. In normal cells this activation is transient and the Stat molecules return to their non-phosphorylated state within a short time period. In tumor cells the balance between activating and de-activating signals is disturbed resulting in the persistent activation of Stat3 or Stat5. The constant activation of Stat3 induces the expression of target genes, which cause the proliferation and survival of cancer cells, as well as their migration and invasive behavior. Activating components of the Jak-Stat pathway have been recognized as potentially valuable drug targets and important principles of compensatory signaling circuit induction during targeted drug treatment have been discovered in the context of kinase inhibition studies in HNSCC cells [1]. The treatment of HNSCC with a specific inhibitor of c-Src, initially resulted in reduced Stat3 and Stat5 activation and subsequently an arrest of cell proliferation and increased apoptosis. However, the inhibition of c-Src only caused a persistent inhibition of Stat5, whereas the inhibition of Stat3 was only transient. The activation of Stat3 was restored within a short time period in the presence of the c-Src inhibitor. This process is mediated through the suppression of P-Stat5 activity and the decrease in the expression of the Stat5 dependent target gene SOCS2, a negative regulator of Jak2. Jak2 activity is enhanced upon SOCS2 downregulation and causes the reactivation of Stat3. A similar observation has been made upon inhibition of Bmx, bone marrow kinase x-linked, activated in the murine glioma cell lines Tu-2449 and Tu-9648. Its inhibition resulted in a transient decrease of P-Stat3 and the induction of a compensatory Stat3 activation mechanism, possibly through the relief of negative feedback inhibition and Jak2 activation. These observations indicate that the inhibition of a single tyrosine kinase might not be sufficient to induce lasting therapeutic effects in cancer patients. Compensatory kinases and pathways might become activated and maintain the growth and survival of tumor cells. The definition of these escape pathways and their preemptive inhibition will suggest effective new combination therapies for cancer.
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Affiliation(s)
| | - Chul Min Yang
- Georg Speyer Haus, Institute for Biomedical Research, Frankfurt am Main, Germany
| | - Diane Richter
- Georg Speyer Haus, Institute for Biomedical Research, Frankfurt am Main, Germany
| | - Natalia Delis
- Georg Speyer Haus, Institute for Biomedical Research, Frankfurt am Main, Germany
| | - Vida Vafaizadeh
- Georg Speyer Haus, Institute for Biomedical Research, Frankfurt am Main, Germany
| | - Bernd Groner
- Georg Speyer Haus, Institute for Biomedical Research, Frankfurt am Main, Germany
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81
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MicroRNA-363-mediated downregulation of S1PR1 suppresses the proliferation of hepatocellular carcinoma cells. Cell Signal 2014; 26:1347-54. [PMID: 24631531 DOI: 10.1016/j.cellsig.2014.02.020] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2013] [Revised: 02/14/2014] [Accepted: 02/26/2014] [Indexed: 12/20/2022]
Abstract
S1PR1 plays a crucial role in promoting proliferation of hepatocellular carcinoma (HCC). Over expression of S1PR1 is observed in HCC cell lines. The mechanisms underlying the aberrant expression of S1PR1 are not known well. MircroRNAs are important regulators of gene expression and disproportionate microRNAs can result in dysregulation of oncogenes in cancer cells. In this study, we found that miR-363, a potential tumor suppressor microRNA, downregulated the expression of S1PR1 and inhibited the proliferation of HCC cells. Bioinformatic analysis predicted a putative binding site of miR-363 within the 3'-UTR of S1PR1 mRNA. Luciferase reporter assay showed that miR-363 directly targeted the 3'-UTR of S1PR1 mRNA. Transfection of miR-363 mimics suppressed S1PR1 expression in HCC cells, followed by the repression of the activation of ERK and STAT3. Moreover, we found that the expression of downstream genes of ERK and STAT3, including PDGF-A, PDGF-B, MCL-1 and Bcl-xL, was suppressed after miR-363 transfection. Taken together, the present study demonstrated that miR-363 was a negative regulator of S1PR1 expression in HCC cells and inhibited cell proliferation, suggesting that the miR-363/S1PR1 pathway might be a novel target for the treatment of HCC.
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82
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Putz EM, Hoelzl MA, Baeck J, Bago-Horvath Z, Schuster C, Reichholf B, Kern D, Aberger F, Sexl V, Hoelbl-Kovacic A. Loss of STAT3 in Lymphoma Relaxes NK Cell-Mediated Tumor Surveillance. Cancers (Basel) 2014; 6:193-210. [PMID: 24473086 PMCID: PMC3980609 DOI: 10.3390/cancers6010193] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2013] [Revised: 01/08/2014] [Accepted: 01/16/2014] [Indexed: 12/31/2022] Open
Abstract
The transcription factors and proto-oncogenes STAT3 and STAT5 are highly activated in hematological malignancies and represent promising therapeutic targets. Whereas the importance of STAT5 as tumor promoter is beyond doubt, the role of STAT3 in hematological cancers is less well understood. Both, enforced as well as attenuated expression of STAT3 were reported in hematopoietic malignancies. Recent evidence implicates STAT3 as key player for tumor immune surveillance as it both mediates the production of and response to inflammatory cytokines. Here we investigated the effects of STAT3 deletion in a BCR/ABL-induced lymphoma model, which is tightly controlled by natural killer (NK) cells in vivo. Upon STAT3 deletion tumor growth is significantly enhanced when compared to STAT3-expressing controls. The increased tumor size upon loss of STAT3 was accompanied by reduced NK cell infiltration and decreased levels of the cytokine IFN-γ and the chemokine RANTES. Upon transplantation into NK cell-deficient mice differences in lymphoma size were abolished indicating that STAT3 expression in the tumor cells controls NK cell-dependent tumor surveillance. Our findings indicate that STAT3 inhibition in lymphoma patients will impair NK cell-mediated tumor surveillance, which needs to be taken into account when testing STAT3 inhibitors in preclinical or clinical trials.
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Affiliation(s)
- Eva Maria Putz
- Institute of Pharmacology and Toxicology, University of Veterinary Medicine, Veterinaerplatz 1, Vienna 1210, Austria.
| | - Maria Agnes Hoelzl
- Institute of Pharmacology, Center for Physiology and Pharmacology, Medical University of Vienna (MUV), Waehringer Strasse 13A, Vienna 1090, Austria.
| | - Julia Baeck
- Institute of Pharmacology and Toxicology, University of Veterinary Medicine, Veterinaerplatz 1, Vienna 1210, Austria.
| | - Zsuzsanna Bago-Horvath
- Institute of Pharmacology and Toxicology, University of Veterinary Medicine, Veterinaerplatz 1, Vienna 1210, Austria.
| | - Christian Schuster
- Institute of Pharmacology, Center for Physiology and Pharmacology, Medical University of Vienna (MUV), Waehringer Strasse 13A, Vienna 1090, Austria.
| | - Brian Reichholf
- Institute of Pharmacology and Toxicology, University of Veterinary Medicine, Veterinaerplatz 1, Vienna 1210, Austria.
| | - Daniela Kern
- Department of Molecular Biology, University of Salzburg, Hellbrunnerstrasse 34, Salzburg 5020, Austria.
| | - Fritz Aberger
- Department of Molecular Biology, University of Salzburg, Hellbrunnerstrasse 34, Salzburg 5020, Austria.
| | - Veronika Sexl
- Institute of Pharmacology and Toxicology, University of Veterinary Medicine, Veterinaerplatz 1, Vienna 1210, Austria.
| | - Andrea Hoelbl-Kovacic
- Institute of Pharmacology and Toxicology, University of Veterinary Medicine, Veterinaerplatz 1, Vienna 1210, Austria.
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