1
|
Grillo M, Palmer C, Holmes N, Sang F, Larner AC, Bhosale R, Shaw PE. Stat3 oxidation-dependent regulation of gene expression impacts on developmental processes and involves cooperation with Hif-1α. PLoS One 2020; 15:e0244255. [PMID: 33332446 PMCID: PMC7746180 DOI: 10.1371/journal.pone.0244255] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Accepted: 12/06/2020] [Indexed: 01/06/2023] Open
Abstract
Reactive oxygen species are bona fide intracellular second messengers that influence cell metabolism and aging by mechanisms that are incompletely resolved. Mitochondria generate superoxide that is dis-mutated to hydrogen peroxide, which in turn oxidises cysteine-based enzymes such as phosphatases, peroxiredoxins and redox-sensitive transcription factors to modulate their activity. Signal Transducer and Activator of Transcription 3 (Stat3) has been shown to participate in an oxidative relay with peroxiredoxin II but the impact of Stat3 oxidation on target gene expression and its biological consequences remain to be established. Thus, we created murine embryonic fibroblasts (MEFs) that express either WT-Stat3 or a redox-insensitive mutant of Stat3 (Stat3-C3S). The Stat3-C3S cells differed from WT-Stat3 cells in morphology, proliferation and resistance to oxidative stress; in response to cytokine stimulation, they displayed elevated Stat3 tyrosine phosphorylation and Socs3 expression, implying that Stat3-C3S is insensitive to oxidative inhibition. Comparative analysis of global gene expression in WT-Stat3 and Stat3-C3S cells revealed differential expression (DE) of genes both under basal conditions and during oxidative stress. Using differential gene regulation pattern analysis, we identified 199 genes clustered into 10 distinct patterns that were selectively responsive to Stat3 oxidation. GO term analysis identified down-regulated genes to be enriched for tissue/organ development and morphogenesis and up-regulated genes to be enriched for cell-cell adhesion, immune responses and transport related processes. Although most DE gene promoters contain consensus Stat3 inducible elements (SIEs), our chromatin immunoprecipitation (ChIP) and ChIP-seq analyses did not detect Stat3 binding at these sites in control or oxidant-stimulated cells, suggesting that oxidised Stat3 regulates these genes indirectly. Our further computational analysis revealed enrichment of hypoxia response elements (HREs) within DE gene promoters, implying a role for Hif-1. Experimental validation revealed that efficient stabilisation of Hif-1α in response to oxidative stress or hypoxia required an oxidation-competent Stat3 and that depletion of Hif-1α suppressed the inducible expression of Kcnb1, a representative DE gene. Our data suggest that Stat3 and Hif-1α cooperate to regulate genes involved in immune functions and developmental processes in response to oxidative stress.
Collapse
Affiliation(s)
- Michela Grillo
- School of Life Sciences, University of Nottingham, Queen’s Medical Centre, Nottingham, United Kingdom
| | - Carolyn Palmer
- School of Life Sciences, University of Nottingham, Queen’s Medical Centre, Nottingham, United Kingdom
| | - Nadine Holmes
- Deep-Seq Unit, School of Life Sciences, University of Nottingham, Queen’s Medical Centre, Nottingham, United Kingdom
| | - Fei Sang
- Deep-Seq Unit, School of Life Sciences, University of Nottingham, Queen’s Medical Centre, Nottingham, United Kingdom
| | - Andrew C. Larner
- Department of Biochemistry and Molecular Biology, Massey Cancer Center, Virginia Commonwealth University, Richmond, Virginia, United States of America
| | - Rahul Bhosale
- School of Biosciences, University of Nottingham, Sutton Bonington, United Kingdom
| | - Peter E. Shaw
- School of Life Sciences, University of Nottingham, Queen’s Medical Centre, Nottingham, United Kingdom
| |
Collapse
|
2
|
Broecker F, Hardt C, Herwig R, Timmermann B, Kerick M, Wunderlich A, Schweiger MR, Borsig L, Heikenwalder M, Lehrach H, Moelling K. Transcriptional signature induced by a metastasis-promoting c-Src mutant in a human breast cell line. FEBS J 2016; 283:1669-88. [PMID: 26919036 DOI: 10.1111/febs.13694] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Revised: 01/20/2016] [Accepted: 02/23/2016] [Indexed: 01/06/2023]
Abstract
UNLABELLED Deletions at the C-terminus of the proto-oncogene protein c-Src kinase are found in the viral oncogene protein v-Src as well as in some advanced human colon cancers. They are associated with increased kinase activity and cellular invasiveness. Here, we analyzed the mRNA expression signature of a constitutively active C-terminal mutant of c-Src, c-Src(mt), in comparison with its wild-type protein, c-Src(wt), in the human non-transformed breast epithelial cell line MCF-10A. We demonstrated previously that the mutant altered migratory and metastatic properties. Genome-wide transcriptome analysis revealed that c-Src(mt) de-regulated the expression levels of approximately 430 mRNAs whose gene products are mainly involved in the cellular processes of migration and adhesion, apoptosis and protein synthesis. 82.9% of these genes have previously been linked to cellular migration, while the others play roles in RNA transport and splicing processes, for instance. Consistent with the transcriptome data, cells expressing c-Src(mt), but not those expressing c-Src(wt), showed the capacity to metastasize into the lungs of mice in vivo. The mRNA expression profile of c-Src(mt)-expressing cells shows significant overlap with that of various primary human tumor samples, possibly reflecting elevated Src activity in some cancerous cells. Expression of c-Src(mt) led to elevated migratory potential. We used this model system to analyze the transcriptional changes associated with an invasive cellular phenotype. These genes and pathways de-regulated by c-Src(mt) may provide suitable biomarkers or targets of therapeutic approaches for metastatic cells. DATABASE This project was submitted to the National Center for Biotechnology Information BioProject under ID PRJNA288540. The Illumina RNA-Seq reads are available in the National Center for Biotechnology Information Sequence Read Archive under study ID SRP060008 with accession numbers SRS977414 for MCF-10A cells, SRS977717 for mock cells, SRS978053 for c-Src(wt) cells and SRS978046 for c-Src(mt) cells.
Collapse
Affiliation(s)
- Felix Broecker
- Max Planck Institute for Molecular Genetics, Berlin, Germany.,University of Zurich, Switzerland
| | | | - Ralf Herwig
- Max Planck Institute for Molecular Genetics, Berlin, Germany
| | | | - Martin Kerick
- Max Planck Institute for Molecular Genetics, Berlin, Germany
| | | | | | - Lubor Borsig
- Institute of Physiology, Zurich Center for Integrative Human Physiology, University of Zurich, Switzerland
| | - Mathias Heikenwalder
- Institute of Virology, Technische Universität München, Germany.,Institute of Virology, Helmholtz Zentrum Munich, Germany.,Department Chronic Inflammation and Cancer, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Hans Lehrach
- Max Planck Institute for Molecular Genetics, Berlin, Germany.,Dahlem Centre for Genome Research and Medical Systems Biology, Berlin, Germany.,Alacris Theranostics GmbH, Berlin, Germany
| | - Karin Moelling
- Max Planck Institute for Molecular Genetics, Berlin, Germany.,University of Zurich, Switzerland
| |
Collapse
|
3
|
Srivastava J, DiGiovanni J. Non-canonical Stat3 signaling in cancer. Mol Carcinog 2015; 55:1889-1898. [PMID: 26649644 DOI: 10.1002/mc.22438] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Revised: 11/06/2015] [Accepted: 11/09/2015] [Indexed: 01/27/2023]
Abstract
Stat3 is a member of the signal transducers and activators of transcription family and is a known regulator of essential biologic processes including angiogenesis, apoptosis, cell cycle progression, and cell migration. Canonical Stat3-mediated signaling involves tyrosine phosphorylation on specific residues that leads to homodimerization and translocation to the nucleus. For many years it was presumed that most, if not all, of the functions of Stat3, both normal and aberrant, were due to the canonical cytokine and growth factor signaling mechanisms. Recent studies suggest that Stat3 functions through alternate non-canonical pathways to bring about some of these biological functions both in normal cells as well as during cancer development and progression. A number of studies have now shown that Stat3 has a function in mitochondria and that unphosphorylated Stat3 (uStat3) can also function as a transcription factor broadening the potential mechanisms involved in Stat3 action. In this review article, we discuss these two main non-canonical functions of Stat3 and their potential roles in oncogenesis. Given the many facets of Stat3 signaling, additional comprehensive investigations are required to fully understand the role of non-canonical Stat3 signaling in cancer and whether these pathways can be targeted for cancer prevention and treatment. © 2015 Wiley Periodicals, Inc.
Collapse
Affiliation(s)
- Jaya Srivastava
- Division of Pharmacology and Toxicology, College of Pharmacy, The University of Texas at Austin, Austin, Texas
| | - John DiGiovanni
- Division of Pharmacology and Toxicology, College of Pharmacy, The University of Texas at Austin, Austin, Texas
| |
Collapse
|
4
|
Deangelis T, Quong A, Morrione A, Baserga R. Growth of v-src-transformed cells in serum-free medium through the induction of growth factors. J Cell Physiol 2012; 228:1482-6. [PMID: 23254450 DOI: 10.1002/jcp.24303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2012] [Accepted: 12/03/2012] [Indexed: 11/09/2022]
Abstract
The v-src oncogene is one of only two oncogenes capable of transforming mouse embryo fibroblasts (MEFs) lacking the IGF-IR gene (R-cells). R-/v-src cells grow robustly in the absence of serum, suggesting the hypothesis that they may produce one or more growth factors that would sustain their ability to proliferate in serum-free condition. Using proteomic approaches on serum-free conditioned media derived from v-src-transformed cells, we have identified two growth promoting factors: ostepontin and proliferin. Subsequent experiments have indicated that osteopontin plays a prevalent role in promoting growth of v-src-transformed cells in serum-deprived condition.
Collapse
Affiliation(s)
- Tiziana Deangelis
- Department of Cancer Biology, Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | | | | | | |
Collapse
|
5
|
Haviland R, Eschrich S, Bloom G, Ma Y, Minton S, Jove R, Cress WD. Necdin, a negative growth regulator, is a novel STAT3 target gene down-regulated in human cancer. PLoS One 2011; 6:e24923. [PMID: 22046235 PMCID: PMC3203112 DOI: 10.1371/journal.pone.0024923] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2010] [Accepted: 08/24/2011] [Indexed: 12/30/2022] Open
Abstract
Cytokine and growth factor signaling pathways involving STAT3 are frequently constitutively activated in many human primary tumors, and are known for the transcriptional role they play in controlling cell growth and cell cycle progression. However, the extent of STAT3's reach on transcriptional control of the genome as a whole remains an important question. We predicted that this persistent STAT3 signaling affects a wide variety of cellular functions, many of which still remain to be characterized. We took a broad approach to identify novel STAT3 regulated genes by examining changes in the genome-wide gene expression profile by microarray, using cells expressing constitutively-activated STAT3. Using computational analysis, we were able to define the gene expression profiles of cells containing activated STAT3 and identify candidate target genes with a wide range of biological functions. Among these genes we identified Necdin, a negative growth regulator, as a novel STAT3 target gene, whose expression is down-regulated at the mRNA and protein levels when STAT3 is constitutively active. This repression is STAT3 dependent, since inhibition of STAT3 using siRNA restores Necdin expression. A STAT3 DNA-binding site was identified in the Necdin promoter and both EMSA and chromatin immunoprecipitation confirm binding of STAT3 to this region. Necdin expression has previously been shown to be down-regulated in a melanoma and a drug-resistant ovarian cancer cell line. Further analysis of Necdin expression demonstrated repression in a STAT3-dependent manner in human melanoma, prostate and breast cancer cell lines. These results suggest that STAT3 coordinates expression of genes involved in multiple metabolic and biosynthetic pathways, integrating signals that lead to global transcriptional changes and oncogenesis. STAT3 may exert its oncogenic effect by up-regulating transcription of genes involved in promoting growth and proliferation, but also by down-regulating expression of negative regulators of the same cellular processes, such as Necdin.
Collapse
Affiliation(s)
- Rachel Haviland
- Molecular Oncology, Moffitt Cancer Center and Research Institute, Tampa, Florida, United States of America
| | - Steven Eschrich
- Biomedical Informatics, Moffitt Cancer Center and Research Institute, Tampa, Florida, United States of America
| | - Gregory Bloom
- Biomedical Informatics, Moffitt Cancer Center and Research Institute, Tampa, Florida, United States of America
| | - Yihong Ma
- Molecular Oncology, Moffitt Cancer Center and Research Institute, Tampa, Florida, United States of America
| | - Susan Minton
- Breast Cancer Program, Moffitt Cancer Center and Research Institute, Tampa, Florida, United States of America
| | - Richard Jove
- Beckman Research Institute, City of Hope National Medical Center, Duarte, California, United States of America
| | - W. Douglas Cress
- Molecular Oncology, Moffitt Cancer Center and Research Institute, Tampa, Florida, United States of America
| |
Collapse
|
6
|
Sudol M. From Rous sarcoma virus to plasminogen activator, src oncogene and cancer management. Oncogene 2011; 30:3003-10. [PMID: 21383693 DOI: 10.1038/onc.2011.38] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Plasminogen activator (PLAU) is a serine protease that converts plasminogen to plasmin, a general protease, which promotes fibrinolysis and degradation of extracellular matrix. PLAU was reported in 1970s as one of the robustly induced enzymatic activities in Rous sarcoma virus (RSV)-transformed chicken cells. More than three decades later, with the completion of the sequencing of the chicken genome and the subsequent availability of Affymetrix GeneChip genome arrays, several laboratories have surveyed the transcriptional program affected by the RSV transformation. Interestingly, the PLAU gene was shown to be the most highly upregulated transcript. The induction of PLAU was a transformation-dependent process because viruses with deleted Src gene did not induce the transcription of the PLAU gene. Both Src and PLAU genes are associated with and contribute to the complex phenotype of human cancer. Although the activity and structures of these two enzymes are well characterized, the precise molecular function of these gene products in signaling networks is still not fully understood. Yet, the knowledge of their association with cancer is already translated into the clinical setting. Src kinase inhibitors are being tested in clinical trials of cancer therapy, and PLAU gene and its inhibitor have been included as biomarkers with strong prognostic and therapeutic predictive values. This vignette reviews the history of PLAU and Src discovery, and illuminates the complexity of their relationship, but also points to their emerging impact on public health.
Collapse
Affiliation(s)
- M Sudol
- Laboratory of Signal Transduction and Proteomic Profiling, Weis Center for Research, Geisinger Clinic, Danville, PA 17822-2608, USA.
| |
Collapse
|
7
|
Maślikowski BM, Néel BD, Wu Y, Wang L, Rodrigues NA, Gillet G, Bédard PA. Cellular processes of v-Src transformation revealed by gene profiling of primary cells--implications for human cancer. BMC Cancer 2010; 10:41. [PMID: 20152043 PMCID: PMC2837010 DOI: 10.1186/1471-2407-10-41] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2009] [Accepted: 02/12/2010] [Indexed: 01/05/2023] Open
Abstract
Background Cell transformation by the Src tyrosine kinase is characterized by extensive changes in gene expression. In this study, we took advantage of several strains of the Rous sarcoma virus (RSV) to characterize the patterns of v-Src-dependent gene expression in two different primary cell types, namely chicken embryo fibroblasts (CEF) and chicken neuroretinal (CNR) cells. We identified a common set of v-Src regulated genes and assessed if their expression is associated with disease-free survival using several independent human tumor data sets. Methods CEF and CNR cells were infected with transforming, non-transforming, and temperature sensitive mutants of RSV to identify the patterns of gene expression in response to v-Src-transformation. Microarray analysis was used to measure changes in gene expression and to define a common set of v-Src regulated genes (CSR genes) in CEF and CNR cells. A clustering enrichment regime using the CSR genes and two independent breast tumor data-sets was used to identify a 42-gene aggressive tumor gene signature. The aggressive gene signature was tested for its prognostic value by conducting survival analyses on six additional tumor data sets. Results The analysis of CEF and CNR cells revealed that cell transformation by v-Src alters the expression of 6% of the protein coding genes of the genome. A common set of 175 v-Src regulated genes (CSR genes) was regulated in both CEF and CNR cells. Within the CSR gene set, a group of 42 v-Src inducible genes was associated with reduced disease- and metastasis-free survival in several independent patient cohorts with breast or lung cancer. Gene classes represented within this group include DNA replication, cell cycle, the DNA damage and stress responses, and blood vessel morphogenesis. Conclusion By studying the v-Src-dependent changes in gene expression in two types of primary cells, we identified a set of 42 inducible genes associated with poor prognosis in breast and lung cancer. The identification of these genes provides a set of biomarkers of aggressive tumor behavior and a framework for the study of cancer cells characterized by elevated Src kinase activity.
Collapse
Affiliation(s)
- Bart M Maślikowski
- Department of Biology, McMaster University, 1280 Main street West, Hamilton, ON, L8S 4K1, Canada
| | | | | | | | | | | | | |
Collapse
|
8
|
Moumtzi SS, Roberts ML, Joyce T, Evangelidou M, Probert L, Frillingos S, Fotsis T, Pintzas A. Gene Expression Profile Associated with Oncogenic Ras-induced Senescence, Cell Death, and Transforming Properties in Human Cells. Cancer Invest 2009; 28:563-87. [DOI: 10.3109/07357900903095623] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
|
9
|
Blocking TLR2 activity attenuates pulmonary metastases of tumor. PLoS One 2009; 4:e6520. [PMID: 19654875 PMCID: PMC2716531 DOI: 10.1371/journal.pone.0006520] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2009] [Accepted: 07/08/2009] [Indexed: 12/26/2022] Open
Abstract
Background Metastasis is the most pivotal cause of mortality in cancer patients. Immune tolerance plays a crucial role in tumor progression and metastasis. Methods and Findings In this study, we investigated the potential roles and mechanisms of TLR2 signaling on tumor metastasis in a mouse model of intravenously injected B16 melanoma cells. Multiple subtypes of TLRs were expressed on B16 cells and several human cancer cell lines; TLR2 mediated the invasive activity of these cells. High metastatic B16 cells released more heat shock protein 60 than poor metastatic B16-F1 cells. Importantly, heat shock protein 60 released by tumor cells caused a persistent activation of TLR2 and was critical in the constitutive activation of transcription factor Stat3, leading to the release of immunosuppressive cytokines and chemokines. Moreover, targeting TLR2 markedly reduced pulmonary metastases and increased the survival of B16-bearing mice by reversing B16 cells induced immunosuppressive microenvironment and restoring tumor-killing cells such as CD8+ T cells and M1 macrophages. Combining an anti-TLR2 antibody and a cytotoxic agent, gemcitabine, provided a further improvement in the survival of tumor-bearing mice. Conclusions and Significance Our results demonstrate that TLR2 is an attractive target against metastasis and that targeting immunosuppressive microenvironment using anti-TLR2 antibody is a novel therapeutic strategy for combating a life-threatening metastasis.
Collapse
|
10
|
Abstract
The c-src proto-oncogene product, c-Src, is frequently over-expressed and activated in various human malignant cancers, implicating a role for c-Src in cancer progression. To verify the role of c-Src, we analyzed the transforming ability of c-Src in mouse embryonic fibroblasts that lack Csk, a negative regulator of Src family kinases. Although Csk deficiency is not sufficient for cell transformation, c-Src over-expression induced characteristic transformed phenotypes including anchorage-independent growth and tumorigenecity. These phenotypes were dose-dependently inhibited by the re-expression of Csk, indicating that there is a certain threshold for c-Src transformation, which is determined by the c-Src : Csk ratio. In contrast to v-Src, c-Src induced the phosphorylation of a limited number of cellular proteins and elicited a restricted change in gene expression profiles. The activation of some critical targets for v-Src transformation, such as STAT3, was not significantly induced by c-Src transformation. Several genes that are involved in cancer progression, that is, cyclin D1 and HIF-1alpha, were induced by v-Src, but not by c-Src. Furthermore, v-Src tumors exhibited aggressive growth and extensive angiogenesis, while c-Src tumors grew more slowly accompanied by the induction of hematomas. These findings demonstrate that c-Src has the potential to induce cell transformation, but it requires coordination with an additional pathway(s) to promote tumor progression in vivo.
Collapse
Affiliation(s)
- Chitose Oneyama
- Department of Oncogene Research, Research Institute of Microbial Diseases, Osaka University, 3-1 Yamada-oka, Suita, Osaka 565-0871, Japan
| | | | | | | |
Collapse
|
11
|
Snyder M, Huang XY, Zhang JJ. Identification of novel direct Stat3 target genes for control of growth and differentiation. J Biol Chem 2007; 283:3791-8. [PMID: 18065416 DOI: 10.1074/jbc.m706976200] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Signal transducer and activator of transcription 3 (Stat3) is a key regulator of gene expression in response to signaling of the glycoprotein 130 (gp130) family cytokines, including interleukin 6, oncostatin M, and leukemia inhibitory factor. Many efforts have been made to identify Stat3 target genes and to understand the mechanism of how Stat3 regulates gene expression. Using the microarray technique, hundreds of genes have been documented to be potential Stat3 target genes in different cell types. However, only a small fraction of these genes have been proven to be true direct Stat3 target genes. Here we report the identification of novel direct Stat3 target genes using a genome-wide screening procedure based on the chromatin immunoprecipitation method. These novel Stat3 target genes are involved in a diverse array of biological processes such as oncogenesis, cell growth, and differentiation. We show that Stat3 can act as both a repressor and activator on its direct target genes. We further show that most of the novel Stat3 direct target genes are dependent on Stat3 for their transcriptional regulation. In addition, using a physiological cell system, we demonstrate that Stat3 is required for the transcriptional regulation of two of the newly identified direct Stat3 target genes important for muscle differentiation.
Collapse
Affiliation(s)
- Marylynn Snyder
- Department of Physiology and Biophysics, Weill Medical College of Cornell University, New York, New York 10021, USA
| | | | | |
Collapse
|
12
|
Stat3 up-regulates expression of nicotinamide N-methyltransferase in human cancer cells. J Cancer Res Clin Oncol 2007; 134:551-9. [PMID: 17922140 DOI: 10.1007/s00432-007-0318-6] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2007] [Accepted: 09/18/2007] [Indexed: 10/22/2022]
Abstract
PURPOSE To discover new molecular targets for cancer therapy and diagnosis, we surveyed signal transducers and activators of transcription 3 (Stat3)-regulated genes, because constitutive activation of Stat3 is associated with a wide variety of human malignancies. METHODS We investigated the Stat3-regulated genes in 293 cells with cDNA microarray analysis and found that Nicotinamide N-methyltransferase (NNMT) was induced on stimulation of the cells with leukemia inhibitory factor. We examined the expression of NNMT in several types of cancer cells by real-time quantitative RT-PCR. To examine the role of Stat3, Hep-G2 hepatocellular carcinoma cells were transfected with NNMT promoter-luciferase reporter construct together with conditionally active Stat3 (Stat3ER) or dominant-negative Stat3 expression vector and NNMT promoter activity was determined. The expression of NNMT and activated Stat3 in 88 colon cancer tissues and 17 normal colon tissues was examined with immunohistochemical analysis. RESULTS In Hep-G2 cells and SW480 colon cancer cells, NNMT expression increased on stimulation of the cells with interleukin 6. NNMT promoter activity in Hep-G2 cells was dependent on the activation of Stat3. MDA-MB-468 breast cancer cells and HT29 colon cancer cells expressed constitutively a high level of NNMT. Treatment of these cells with Stat3 siRNA or curcumin, which inhibited Stat3 phosphorylation, resulted in reduction of the NNMT level. We found a correlation between the expression of NNMT and activated Stat3 (P<0.001) in the colon cancer tissues. CONCLUSION NNMT is a novel Stat3-regulated gene. Its expression is enhanced with the activation of Stat3 in colon cancer tissues. NNMT may be a potential candidate for a tumor marker of various kinds of cancers.
Collapse
|
13
|
Masker K, Golden A, Gaffney CJ, Mazack V, Schwindinger WF, Zhang W, Wang LH, Carey DJ, Sudol M. Transcriptional profile of Rous Sarcoma Virus transformed chicken embryo fibroblasts reveals new signaling targets of viral-src. Virology 2007; 364:10-20. [PMID: 17448514 PMCID: PMC1974879 DOI: 10.1016/j.virol.2007.03.026] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2007] [Revised: 03/05/2007] [Accepted: 03/15/2007] [Indexed: 01/05/2023]
Abstract
Transformation of chicken fibroblasts in vitro by Rous Sarcoma Virus represents a model of cancer in which a single oncogene, viral src, uniformly and rapidly transforms primary cells in culture. We experimentally surveyed the transcriptional program affected by Rous Sarcoma Virus (RSV) in primary culture of chicken embryo fibroblasts. As a control, we used cells infected with non-transforming RSV mutant td106, in which the src gene was deleted. Using Affymetrix GeneChip Chicken Genome Arrays, we report 811 genes that were modulated more than 2.5 fold in the virus transformed cells. Among these, 409 genes were induced and 402 genes were repressed by viral src. From the repertoire of modulated genes, we selected 20 genes that were robustly changed. We then validated and quantified the transcriptional changes of most of the 20 selected genes by real-time PCR. The set of strongly induced genes contains vasoactive intestinal polypeptide, MAP kinase phosphatase 2 and follistatin, among others. The set of strongly repressed genes contains TGF beta 3, TGF beta-induced gene, and deiodinase. The function of several robustly modulated genes sheds new light on the molecular mechanism of oncogenic transformation.
Collapse
Affiliation(s)
| | | | | | | | | | - Weizhou Zhang
- Department of Microbiology, Mount Sinai School of Medicine, New York, NY, USA
| | - Lu-Hai Wang
- Department of Microbiology, Mount Sinai School of Medicine, New York, NY, USA
| | | | - Marius Sudol
- Weis Center for Research, Danville, PA, USA
- Department of Medicine, Mount Sinai School of Medicine, New York, NY, USA
- *Correspondence: M Sudol, Laboratory of Signal Transduction and Proteomic Profiling, Weis Center for Research, 100 North Academy Avenue, Lab 202, Danville, PA 17822-2608, USA. Phone: 1-570-271-6677, e.mail:
| |
Collapse
|
14
|
Azare J, Leslie K, Al-Ahmadie H, Gerald W, Weinreb PH, Violette SM, Bromberg J. Constitutively activated Stat3 induces tumorigenesis and enhances cell motility of prostate epithelial cells through integrin beta 6. Mol Cell Biol 2007; 27:4444-53. [PMID: 17438134 PMCID: PMC1900039 DOI: 10.1128/mcb.02404-06] [Citation(s) in RCA: 125] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
The persistent activation of signal transducer and activator of transcription 3 (Stat3) is a common feature of prostate cancer. However, little is known about the Stat3 targets that may mediate prostate tumorigenesis. The introduction of an activating mutant form of Stat3 (Stat3-C) into immortalized prostate epithelial cells resulted in tumorigenesis. Stat3-C-expressing cells had decreased E-cadherin levels, increased numbers of lamellipodia and stress fibers, and enhanced migratory capacities compared to vector control-expressing cells, with a concomitant increase in the expression of integrin beta6 and its ligand, fibronectin (FN). Exogenously added FN increased cellular migration, with a concomitant loss of E-cadherin expression. The blockade of integrin alphavbeta6 in Stat3-C-expressing cells inhibited migration, increased E-cadherin levels, and reduced colony formation in soft agar. These results demonstrate the sufficiency of constitutively activated Stat3 in mediating prostate tumorigenesis and identify novel Stat3 targets that are involved in promoting cell migration and transformation.
Collapse
Affiliation(s)
- Janeen Azare
- Department of Medicine, Memorial Sloan-Kettering Cancer Center, New York, NY 10021, USA
| | | | | | | | | | | | | |
Collapse
|
15
|
Smilowitz HM, Weissenberger J, Weis J, Brown JD, O'Neill RJ, Laissue JA. Orthotopic transplantation of v-src–expressing glioma cell lines into immunocompetent mice: establishment of a new transplantable in vivo model for malignant glioma. J Neurosurg 2007; 106:652-9. [PMID: 17432718 DOI: 10.3171/jns.2007.106.4.652] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Object
The aim of this study was to develop and characterize a new orthotopic, syngeneic, transplantable mouse brain tumor model by using the cell lines Tu-9648 and Tu-2449, which were previously isolated from tumors that arose spontaneously in glial fibrillary acidic protein (GFAP)-v-src transgenic mice.
Methods
Striatal implantation of a 1-μl suspension of 5000 to 10,000 cells from either clone into syngeneic B6C3F1 mice resulted in tumors that were histologically identified as malignant gliomas. Prior subcutaneous inoculations with irradiated autologous cells inhibited the otherwise robust development of a microscopically infiltrating malignant glioma. Untreated mice with implanted tumor cells were killed 12 days later, when the resultant gliomas were several millimeters in diameter. Immunohistochemically, the gliomas displayed both the astroglial marker GFAP and the oncogenic form of signal transducer and activator of transcription–3 (Stat3). This form is called tyrosine-705 phosphorylated Stat3, and is found in many malignant entities, including human gliomas. Phosphorylated Stat3 was particularly prominent, not only in the nucleus but also in the plasma membrane of peripherally infiltrating glioma cells, reflecting persistent overactivation of the Janus kinase/Stat3 signal transduction pathway. The Tu-2449 cells exhibited three non-random structural chromosomal aberrations, including a deletion of the long arm of chromosome 2 and an apparently balanced translocation between chromosomes 1 and 3. The GFAP-v-src transgene was mapped to the pericentromeric region of chromosome 18.
Conclusions
The high rate of engraftment, the similarity to the high-grade malignant glioma of origin, and the rapid, locally invasive growth of these tumors should make this murine model useful in testing novel therapies for human malignant gliomas.
Collapse
Affiliation(s)
- Henry M Smilowitz
- Department of Pharmacology, University of Connecticut Health Center, Farmington, Connecticut 06030, USA.
| | | | | | | | | | | |
Collapse
|
16
|
Sun W, Snyder M, Levy DE, Zhang JJ. Regulation of Stat3 transcriptional activity by the conserved LPMSP motif for OSM and IL-6 signaling. FEBS Lett 2006; 580:5880-4. [PMID: 17027757 DOI: 10.1016/j.febslet.2006.09.054] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2006] [Revised: 09/15/2006] [Accepted: 09/25/2006] [Indexed: 11/20/2022]
Abstract
To achieve maximal transcriptional activity in response to gp130 cytokines, Serine-727 (Ser-727) of Stat3 is phosphorylated. Ser-727 resides in the LPMSP motif, the only conserved sequence among the transcription activation domains of several STATs. We show here that in addition to Ser-727, other residues in this LPMSP motif are also required for Stat3 activity in response to cytokine signaling through regulation of Ser-727 phosphorylation and recruitment of the transcription co-activator CBP/p300 to the promoters of Stat3-target genes for transcription activation. Hence, we have demonstrated a critical role for the whole conserved LPMSP motif in JAK-STAT signaling.
Collapse
Affiliation(s)
- Wei Sun
- Department of Physiology and Biophysics, Weill Medical College of Cornell University, 1300 York Avenue, New York, NY 10021, USA
| | | | | | | |
Collapse
|
17
|
Wojcik EJ, Sharifpoor S, Miller NA, Wright TG, Watering R, Tremblay EA, Swan K, Mueller CR, Elliott BE. A novel activating function of c-Src and Stat3 on HGF transcription in mammary carcinoma cells. Oncogene 2006; 25:2773-84. [PMID: 16407846 DOI: 10.1038/sj.onc.1209306] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
In the normal breast, hepatocyte growth factor (HGF) is primarily expressed by stromal cells, and stimulates in a paracrine manner epithelial cells expressing the HGF receptor (Met). In invasive human breast carcinomas, HGF and Met are frequently overexpressed, possibly establishing an autocrine HGF/Met loop that promotes tumour cell invasion. However, the mechanisms leading to autocrine HGF expression in carcinoma cells are not known. We previously demonstrated a cooperative effect between c-Src and Stat3 in the activation of HGF transcription in mammary carcinoma cells. The present report defines a novel Stat3 consensus site at nt -95 in the HGF promoter that is highly conserved in human and mouse, and is required for c-Src and Stat3 to activate HGF transcription in breast epithelial cells. DNA-protein binding studies demonstrated high affinity binding of a Stat3-containing complex to the nt -95 site. Endogenous Stat3 binding to this region of the HGF promoter in carcinoma cells expressing HGF was demonstrated using a chromatin immunoprecipitation assay. In addition, coexpression of Stat3 and activated c-Src caused increased expression of endogenous HGF mRNA and protein and marked cell scattering in breast epithelial cells. Our results delineate a novel c-Src/Stat3-dependent mechanism that regulates HGF promoter activity, and is linked to transformation of mammary epithelial cells.
Collapse
Affiliation(s)
- E J Wojcik
- Department of Pathology and Molecular Medicine, Division of Cancer Biology and Genetics, Queen's University Cancer Research Institute, Kingston, ON, Canada
| | | | | | | | | | | | | | | | | |
Collapse
|
18
|
Leslie K, Lang C, Devgan G, Azare J, Berishaj M, Gerald W, Kim YB, Paz K, Darnell JE, Albanese C, Sakamaki T, Pestell R, Bromberg J. Cyclin D1 is transcriptionally regulated by and required for transformation by activated signal transducer and activator of transcription 3. Cancer Res 2006; 66:2544-52. [PMID: 16510571 DOI: 10.1158/0008-5472.can-05-2203] [Citation(s) in RCA: 198] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Signal transducers and activators of transcription 3 (STAT3) is a transcription factor that is aberrantly activated in many cancer cells. Constitutively activated STAT3 is oncogenic, presumably as a consequence of the genes that it differentially regulates. Activated STAT3 correlated with elevated cyclin D1 protein in primary breast tumors and breast cancer-derived cell lines. Cyclin D1 mRNA levels were increased in primary rat-, mouse-, and human-derived cell lines expressing either the oncogenic variant of STAT3 (STAT3-C) or vSrc, which constitutively phosphorylates STAT3. Mutagenesis of STAT3 binding sites within the cyclin D1 promoter and chromatin immunoprecipitation studies showed an association between STAT3 and the transcriptional regulation of the human cyclin D1 gene. Introduction of STAT3-C and vSrc into immortalized cyclin D1(-/-) and cyclin D1(-/+) fibroblasts led to anchorage-independent growth of only cyclin D1(-/+) cells. Furthermore, knockdown of cyclin D1 in breast carcinoma cells led to a reduction in anchorage-independent growth. Phosphorylation of the retinoblastoma (Rb) protein [a target of the cyclin D1/cyclin-dependent kinase 4/6 (cdk4/6) holoenzyme] was delayed in the cyclin D1(-/-) cells relative to cyclin D1(-/+) cells. The E7 oncogene, whose activity includes degradation of Rb and dissociation of Rb from E2F, did not confer anchorage-independent growth to the cyclin D1(-/-) cells but, in conjunction with vSrc, resulted in robust growth in soft agar. These results suggest both a cdk-dependent and cdk-independent role for cyclin D1 in modulating transformation by different oncogenes.
Collapse
Affiliation(s)
- Kenneth Leslie
- Department of Medicine, Memorial Sloan-Kettering Cancer Center, New York, NY 10021, USA
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
19
|
Abstract
The restoration of catalytic activity to mutant enzymes by small molecules is well established for in vitro systems. Here, we show that the protein tyrosine kinase Src arginine-388-->alanine (R388A) mutant can be rescued in live cells with the use of the small molecule imidazole. Cellular rescue of a viral Src homolog was rapid and reversible and conferred predicted oncogenic properties. Using chemical rescue in combination with mass spectrometry, we confirmed six known Src kinase substrates and identified several new protein targets. Chemical rescue data suggest that cellular Src is active under basal conditions. Rescue of R388A cellular Src provided insights into the mitogen-activated protein kinase pathway. This chemical rescue approach will likely have many applications in cell signaling.
Collapse
Affiliation(s)
- Yingfeng Qiao
- Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | | | | | | | | |
Collapse
|
20
|
Paz K, Brennan LA, Iacolina M, Doody J, Hadari YR, Zhu Z. Human single-domain neutralizing intrabodies directed against Etk kinase: a novel approach to impair cellular transformation. Mol Cancer Ther 2006; 4:1801-9. [PMID: 16276002 DOI: 10.1158/1535-7163.mct-05-0174] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Etk, the 70-kDa member of the Tec family of nonreceptor protein tyrosine kinases, is expressed in a variety of hematopoietic, epithelial, and endothelial cells and was shown to be involved in several cellular processes, including proliferation, differentiation, and motility. In this study, we describe a novel approach using a human single-domain antibody phage display library for the generation of intrabodies directed against Etk. These single-domain antibodies bind specifically to recombinant Etk and efficiently block its kinase activity. When expressed in transformed cells, these antibodies associated tightly with Etk, leading to significant blockade of Etk enzymatic activity and inhibition of clonogenic cell growth in soft agar. Our results indicate that Etk may play a role in Src-induced cellular transformation and thus may represent a good target for cancer intervention. Furthermore, our single-domain antibody-based intrabody system proves to be an excellent tool for future intracellular targeting of other signaling molecules.
Collapse
Affiliation(s)
- Keren Paz
- Department of Antibody Technology and Protein Sciences, ImClone Systems, 180 Varick Street, New York, New York 10014, USA.
| | | | | | | | | | | |
Collapse
|
21
|
Hsieh FC, Cheng G, Lin J. Evaluation of potential Stat3-regulated genes in human breast cancer. Biochem Biophys Res Commun 2005; 335:292-9. [PMID: 16081048 DOI: 10.1016/j.bbrc.2005.07.075] [Citation(s) in RCA: 145] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2005] [Accepted: 07/08/2005] [Indexed: 12/13/2022]
Abstract
The constitutive activation of signal transducer and activator of transcription 3 (Stat3) is frequently detected in breast cancer tissues and cell lines. Stat3 has been classified as a proto-oncogene, because an activated form of Stat3 can mediate oncogenic transformation in cultured cells and tumor formation in nude mice. Since Stat3 may play an important role in breast cancer, it is of interest to investigate the expression of phosphorylated Stat3, an activated form of Stat3, and its downstream mediators specifically in breast cancer, and to explore the possible mechanisms of Stat3 signaling pathway in oncogenesis of breast cancer. We analyzed Stat3 phosphorylation and expression of Stat3-regulated genes in breast cancer cell lines as well as invasive breast cancer tissues using tissue microarray slides. Our results showed that elevated levels of phosphorylation of Stat3 protein (Tyr705) were detected in 48 out of total 136 invasive breast tumors (35%) whereas normal breast tissues express much lower levels of Stat3 phosphorylation. The increased levels of Stat3 phosphorylation were associated with the metastasis in regional lymph nodes (P=0.042) and the expression of progesterone receptor (P=0.028) but not with distant metastasis, nor the expression of estrogen receptor. Our results also indicate that elevated levels of Stat3 phosphorylation were significantly associated with increased expression of potential downstream targets of Stat3 which include apoptosis inhibitors (Survivin, Mcl-1, HSP27, Adrenomedullin, and Bcl-xL), cell-cycle regulators (c-Fos, MEK5, and c-Myc), and inducer of tumor angiogenesis (VEGF, COX-2, MMP-2, MMP-10, and MMP-1) in invasive breast cancer tissues. Therefore, our findings suggest that constitutive Stat3 signaling may be one of the key upstream regulators to induce these downstream proteins, which may play important roles in Stat3-mediated oncogenesis in breast cancer.
Collapse
Affiliation(s)
- Fu-Chuan Hsieh
- Center for Childhood Cancer, Columbus Children's Research Institute, The Ohio State University, Columbus, OH 43205, USA
| | | | | |
Collapse
|