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Park CY, Son JY, Jin CH, Nam JS, Kim DK, Sheen YY. EW-7195, a novel inhibitor of ALK5 kinase inhibits EMT and breast cancer metastasis to lung. Eur J Cancer 2011; 47:2642-53. [PMID: 21852112 DOI: 10.1016/j.ejca.2011.07.007] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2011] [Revised: 06/07/2011] [Accepted: 07/15/2011] [Indexed: 01/01/2023]
Abstract
Recently, researchers are actively pursuing efforts to develop potent and selective ALK5 (TβRI) kinase inhibitors for clinical development. In this study, the authors examined a novel small molecule inhibitor of ALK5, 3-((4-([1,2,4]triazolo[1,5-a]pyridin-6-yl)-5-(6-methylpyridin-2-yl)-1H-imidazol-2-yl)methylamino)benzonitrile (EW-7195) to determine if it has potential for cancer treatment. The inhibitory effects of EW-7195 on TGF-β-induced Smad signaling and epithelial-to-mesenchymal transition (EMT) were investigated in mammary epithelial cells using luciferase reporter assays, immunoblotting, confocal microscopy and wound healing assays. In addition, the suppressive effects of EW-7195 on mammary cancer metastasis to lung were examined using a Balb/c xenograft and MMTV/cNeu transgenic mice model system. The novel ALK5 inhibitor, EW-7195, inhibited the TGF-β(1)-stimulated transcriptional activations of p3TP-Lux and pCAGA(12)-Luc. In addition, EW-7195 decreased phosphorylated Smad2 levels and the nuclear translocation of Smad2 increased by TGF-β(1). In addition, EW-7195 inhibited TGF-β(1)-induced EMT and wound healing of NMuMG cells. Furthermore, in xenografted Balb/c and MMTV/cNeu mice, EW-7195 inhibited metastasis to lung from breast tumours. The novel ALK5 inhibitor, EW-7195, efficiently inhibited TGF-β(1)-induced Smad signaling, EMT and breast tumour metastasis to the lung in vivo, demonstrating that EW-7195 has therapeutic potential for the breast cancer metastasis to the lung.
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Affiliation(s)
- Chul-Yong Park
- College of Pharmacy, Ewha Womans University, Seodaemun-gu, Seoul, Republic of Korea
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Distinct role of endocytosis for Smad and non-Smad TGF-β signaling regulation in hepatocytes. J Hepatol 2011; 55:369-78. [PMID: 21184784 DOI: 10.1016/j.jhep.2010.11.027] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2010] [Revised: 10/10/2010] [Accepted: 11/02/2010] [Indexed: 01/11/2023]
Abstract
BACKGROUND & AIMS In injured liver, TGF-β affects all hepatic cell types and participates in wound healing and fibrogenesis. TGF-β downstream signaling is highly complex and cell type dependent, involving Smad and non-Smad signaling cascades thus requiring tight regulation. Endocytosis has gained relevance as important mechanism to control signaling initiation and termination. In this study, we investigated endocytic mechanisms for TGF-β mediated Smad and non-Smad signaling in hepatocytes. METHODS Endocytosis in hepatocytes was elucidated using chemical inhibitors, RNAi, viral gene transfer and caveolin-1-/- mice. TGF-β signaling was monitored by Western blot, reporter assays and gene expression analysis. RESULTS In hepatocytes, Smad activation is to a large degree accomplished AP-2 complex dependent on the hepatocyte surface without the necessity of clathrin coated pit formation or an endocytic step. In contrast, non-Smad/AKT pathway activation required functional dynamin mediated endocytosis and the presence of caveolin-1, an essential protein for caveolae formation. Furthermore, these two TGF-β signaling initiation platforms discriminate distinct signaling routes that integrate at the transcriptional level as shown for TGF-β target genes, Id1, Smad7, and CTGF. Endocytosis inhibition increased canonical Smad signaling and culminated in a superinduction of Id1 and Smad7 expression, whereas caveolin-1 mediated AKT pathway activation was required for maximal CTGF induction. CONCLUSIONS Endocytosis is critical for TGF-β signaling regulation in hepatocytes and determines gene expression signature and (patho)physiological outcome.
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Chandramouli A, Simundza J, Pinderhughes A, Cowin P. Choreographing metastasis to the tune of LTBP. J Mammary Gland Biol Neoplasia 2011; 16:67-80. [PMID: 21494784 PMCID: PMC3747963 DOI: 10.1007/s10911-011-9215-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2011] [Accepted: 03/20/2011] [Indexed: 12/20/2022] Open
Abstract
Latent Transforming Growth Factor beta (TGFβ) Binding Proteins (LTBPs) are chaperones and determinants of TGFβ isoform-specific secretion. They belong to the LTBP/Fibrillin family and form integral components of the fibronectin and microfibrillar extracellular matrix (ECM). LTBPs serve as master regulators of TGFβ bioavailability, functioning to incorporate and spatially pattern latent TGFβ at regular intervals within the ECM, and actively participate in integrin-mediated stretch activation of TGFβ in vivo. In so doing they create a highly patterned sensory system where local changes in ECM tension can be detected and transduced into focal signals. The physiological role of LTBPs in the mammary gland remains largely unstudied, however both loss and gain of LTBP expression is found in breast cancers and breast cancer cell lines. Importantly, elevated LTBP1 levels appear in two gene signatures predictive of enhanced metastatic behavior. LTBP may promote metastasis by providing the bridge between structural and signaling components of the epithelial to mesenchymal transition (EMT).
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Affiliation(s)
- Anupama Chandramouli
- Department of Dermatology, New York University School of Medicine, New York, NY, USA
| | - Julia Simundza
- Department of Cell Biology, MSB 621, New York University School of Medicine, 550 First Ave, New York, NY 10016, USA
| | - Alicia Pinderhughes
- Department of Cell Biology, MSB 621, New York University School of Medicine, 550 First Ave, New York, NY 10016, USA
| | - Pamela Cowin
- Department of Dermatology, New York University School of Medicine, New York, NY, USA
- Department of Cell Biology, MSB 621, New York University School of Medicine, 550 First Ave, New York, NY 10016, USA
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Chow A, Arteaga CL, Wang SE. When tumor suppressor TGFβ meets the HER2 (ERBB2) oncogene. J Mammary Gland Biol Neoplasia 2011; 16:81-8. [PMID: 21590373 PMCID: PMC3398103 DOI: 10.1007/s10911-011-9206-4] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2011] [Accepted: 03/07/2011] [Indexed: 12/28/2022] Open
Abstract
Despite its tumor suppressive role in normal mammary epithelial cells, TGFβ has been reported to promote the migration, invasion and survival in breast cancer cells overexpressing the HER2 (ERBB2; neu) oncogene, and to accelerate the metastasis of neu-induced mammary tumors in mice. A clearer understanding of the molecular mechanisms underlying the crosstalk between TGFβ and HER2 has started to emerge. In recent studies reviewed here, the synergistic effect of TGFβ and HER2 on tumor progression has been shown to likely be a combined result of two distinct features: (1) loss of TGFβ's tumor suppressive effect through functional alterations in the anti-mitogenic effect of Smad-mediated transcription, and (2) gain of pro-survival and pro-migratory function through HER2-dependent mechanisms. In HER2-overexpressing breast cancer, this crosstalk results in increased cancer cell proliferation, survival and invasion, accelerated metastasis in animal models, and resistance to chemotherapy and HER2-targeted therapy. Thus, the transformed cellular context imparted by constitutively active HER2 signaling, as a consequence of HER2 gene amplification or overexpression, aborts the tumor suppressive role of TGFβ and facilitated the oncogenic role of this pathway. In turn, TGFβ potentiates oncogenic HER2 signaling by inducing shedding of the ERBB ligands and clustering of HER2 with integrins. Here we discuss recent studies examining Smad-dependent and -independent mechanisms of crosstalk between TGFβ and HER2. Therefore, blockade of TGFβ:HER2 crosstalk may suppress breast cancer progression and metastasis, and enhance the efficiency of conventional therapies in patients with HER2-overexpressing breast cancer.
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Affiliation(s)
- Amy Chow
- Division of Tumor Cell Biology, Department of Cancer Biology, Beckman Research Institute of City of Hope, Duarte, CA 91010, USA
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Sun H, Hu K, Wu M, Xiong J, Yuan L, Tang Y, Yang Y, Liu H. Contact by melanoma cells causes malignant transformation of human epithelial-like stem cells via alpha V integrin activation of transforming growth factor β1 signaling. Exp Biol Med (Maywood) 2011; 236:352-65. [PMID: 21427239 DOI: 10.1258/ebm.2010.010106] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The embryonic microenvironment is known to suppress the tumorigenic phenotype of aggressive cancer cells; however, the effects of tumorigenic microenvironments on stem cells have not been sufficiently explored due to the lack of suitable model systems. In order to study the tumorigenic microenviornment, we developed a novel in vitro model system for induction of malignant transformation of human epithelial-like stem cells (hEpSCs), involving co-cultivation and close contact of hEpSCs with the A375 melanoma cell line, together with mutagen treatment of hEpSCs with dimethylbenzanthracene (DMBA). Both factors (close contact and mutagen treatment) were required to transform hEpSCs in vitro and cause phenotypic changes characteristic of epithelial to mesenchymal transition (EMT), including colony formation, decreased E-cadherin and increased N-cadherin and vimentin expression. Direct contact between tumor cells and hEpSCs treated with DMBA increased integrin alpha V (ITGAV gene) expression and caused local activation of the transforming growth factor (TGF)-β1/Smad signaling pathways in hEpSCs. The novel model system described here is being used to elucidate the microenvironmental factors and biological mechanisms involved in the induction of neoplastic progression in hEpSCs in vitro by A375 melanoma cells. A better understanding of the molecular mechanisms by which melanoma cells exert these effects on hEpSCs may open up new avenues for therapeutic and preventive cancer interventions.
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Affiliation(s)
- Hongyu Sun
- Research Center of Developmental Biology and Department of Histology and Embryology, Second Military Medical University, Shanghai, China
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Yeh ES, Yang TW, Jung JJ, Gardner HP, Cardiff RD, Chodosh LA. Hunk is required for HER2/neu-induced mammary tumorigenesis. J Clin Invest 2011; 121:866-79. [PMID: 21393859 PMCID: PMC3049391 DOI: 10.1172/jci42928] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2010] [Accepted: 12/29/2010] [Indexed: 12/20/2022] Open
Abstract
Understanding the molecular pathways that contribute to the aggressive behavior of human cancers is a critical research priority. The SNF1/AMPK-related protein kinase Hunk is overexpressed in aggressive subsets of human breast, ovarian, and colon cancers. Analysis of Hunk(–/–) mice revealed that this kinase is required for metastasis of c-myc–induced mammary tumors but not c-myc–induced primary tumor formation. Similar to c-myc, amplification of the proto-oncogene HER2/neu occurs in 10%–30% of breast cancers and is associated with aggressive tumor behavior. By crossing Hunk(–/–) mice with transgenic mouse models for HER2/neu-induced mammary tumorigenesis, we report that Hunk is required for primary tumor formation induced by HER2/neu. Knockdown and reconstitution experiments in mouse and human breast cancer cell lines demonstrated that Hunk is required for maintenance of the tumorigenic phenotype in HER2/neu-transformed cells. This requirement is kinase dependent and resulted from the ability of Hunk to suppress apoptosis in association with downregulation of the tumor suppressor p27(kip1). Additionally, we find that Hunk is rapidly upregulated following HER2/neu activation in vivo and in vitro. These findings provide what we believe is the first evidence for a role for Hunk in primary tumorigenesis and cell survival and identify this kinase as an essential effector of the HER2/neu oncogenic pathway.
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Affiliation(s)
- Elizabeth S. Yeh
- Department of Cancer Biology, Department of Cell and Developmental Biology, Department of Medicine, and Abramson Family Cancer Research Institute, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA.
Department of Pathology and Laboratory Medicine School of Medicine, University of California Davis Center for Comparative Medicine, UCD, Davis, California, USA
| | - Thomas W. Yang
- Department of Cancer Biology, Department of Cell and Developmental Biology, Department of Medicine, and Abramson Family Cancer Research Institute, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA.
Department of Pathology and Laboratory Medicine School of Medicine, University of California Davis Center for Comparative Medicine, UCD, Davis, California, USA
| | - Jason J. Jung
- Department of Cancer Biology, Department of Cell and Developmental Biology, Department of Medicine, and Abramson Family Cancer Research Institute, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA.
Department of Pathology and Laboratory Medicine School of Medicine, University of California Davis Center for Comparative Medicine, UCD, Davis, California, USA
| | - Heather P. Gardner
- Department of Cancer Biology, Department of Cell and Developmental Biology, Department of Medicine, and Abramson Family Cancer Research Institute, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA.
Department of Pathology and Laboratory Medicine School of Medicine, University of California Davis Center for Comparative Medicine, UCD, Davis, California, USA
| | - Robert D. Cardiff
- Department of Cancer Biology, Department of Cell and Developmental Biology, Department of Medicine, and Abramson Family Cancer Research Institute, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA.
Department of Pathology and Laboratory Medicine School of Medicine, University of California Davis Center for Comparative Medicine, UCD, Davis, California, USA
| | - Lewis A. Chodosh
- Department of Cancer Biology, Department of Cell and Developmental Biology, Department of Medicine, and Abramson Family Cancer Research Institute, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA.
Department of Pathology and Laboratory Medicine School of Medicine, University of California Davis Center for Comparative Medicine, UCD, Davis, California, USA
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Lu Y, Jiang F, Zheng X, Katakowski M, Buller B, To SST, Chopp M. TGF-β1 promotes motility and invasiveness of glioma cells through activation of ADAM17. Oncol Rep 2011; 25:1329-35. [PMID: 21359495 DOI: 10.3892/or.2011.1195] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2010] [Accepted: 12/27/2010] [Indexed: 01/29/2023] Open
Abstract
The transforming growth factor β1 (TGF-β1) belongs to a family of structurally related polypeptide factors. TGF-beta plays an important role in the pathobiology of invasion of malignant gliomas. The objective of the present study was to investigate the impact of TNF-α converting enzyme (TACE/ADAM17) signaling on the process of TGF-β1-stimulated migration and invasion of T98G glioma cells. We found that TGF-β1 increased migration and invasiveness in glioma cells. Addition of the TGF-β1 receptor inhibitor, SB431542, reduced the TGF-β1-stimulated migration and invasiveness of glioma cells. In addition, TGF-β1-induced migration and invasiveness were also blocked by exposure to an ADAM17 inhibitor, TAPI-2. Furthermore, ADAM17 mRNA and protein expression were up-regulated by TGF-β1. Treatment with SB431542 and TAPI-2 blocked TGF-β1-induced ADAM17 protein expression. In summary, these results indicate that TGF-β1 promotes cell migration and invasiveness of glioma cells through stimulation of ADAM17.
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Affiliation(s)
- Yong Lu
- Department of Health Technology and Informatics, The Hong Kong Polytechnic University, Hong Kong SAR, PR China
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Gauger KJ, Chenausky KL, Murray ME, Schneider SS. SFRP1 reduction results in an increased sensitivity to TGF-β signaling. BMC Cancer 2011; 11:59. [PMID: 21303533 PMCID: PMC3041779 DOI: 10.1186/1471-2407-11-59] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2010] [Accepted: 02/08/2011] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Transforming growth factor (TGF)-β plays a dual role during mammary gland development and tumorigenesis and has been shown to stimulate epithelial-mesenchymal transition (EMT) as well as cellular migration. The Wnt/β-catenin pathway is also implicated in EMT and inappropriate activation of the Wnt/β-catenin signaling pathway leads to the development of several human cancers, including breast cancer. Secreted frizzled-related protein 1 (SFRP1) antagonizes this pathway and loss of SFRP1 expression is frequently observed in breast tumors and breast cancer cell lines. We previously showed that when SFRP1 is knocked down in immortalized non-malignant mammary epithelial cells, the cells (TERT-siSFRP1) acquire characteristics associated with breast tumor initiating cells. The phenotypic and genotypic changes that occur in response to SFRP1 loss are consistent with EMT, including a substantial increase in the expression of ZEB2. Considering that ZEB2 has been shown to interact with mediators of TGF-β signaling, we sought to determine whether TGF-β signaling is altered in TERT-siSFRP1 cells. METHODS Luciferase reporter assays and real-time PCR analysis were employed to measure TGF-β transcriptional targets. Western blot analysis was used to evaluate TGF-β-mediated ERK1/2 phosphorylation. Migration chamber assays were utilized to quantify cellular migration. TERT-siSFRP1 cells were transfected with Stealth RNAi™ siRNA in order to knock-down the expression of ZEB2. RESULTS TERT-siSFRP1 cells exhibit a significant increase in both TGF-β-mediated luciferase activity as well as TGF-β transcriptional targets, including Integrin β3 and PAI-1. Phosphorylation of ERK1/2 is increased in TERT-siSFRP1 cells in response to enhanced TGF-β signaling. Furthermore, when the TGF-β pathway is blocked with a TGF-βR antagonist (LY364947), cellular migration is significantly hindered. Finally, we found that when ZEB2 is knocked-down, there is a significant reduction in the expression of exogeneous and endogenous TGF-β transcriptional targets and cellular migration is impeded. CONCLUSIONS We demonstrate that down-regulation of SFRP1 renders mammary epithelial cells more sensitive to TGF-β signaling which can be partially ameliorated by blocking the expression of ZEB2.
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Affiliation(s)
- Kelly J Gauger
- Pioneer Valley Life Sciences Institute, Baystate Medical Center, Springfield, MA 01199, USA.
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Moses H, Barcellos-Hoff MH. TGF-beta biology in mammary development and breast cancer. Cold Spring Harb Perspect Biol 2011; 3:a003277. [PMID: 20810549 DOI: 10.1101/cshperspect.a003277] [Citation(s) in RCA: 170] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Transforming growth factor-β1 (TGF-β) was first implicated in mammary epithelial development by Daniel and Silberstein in 1987 and in breast cancer cells and hormone resistance by Lippman and colleagues in 1988. TGF-β is critically important for mammary morphogenesis and secretory function through specific regulation of epithelial proliferation, apoptosis, and extracellular matrix. Differential TGF-β effects on distinct cell types are compounded by regulation at multiple levels and the influence of context on cellular responses. Studies using controlled expression and conditional-deletion mouse models underscore the complexity of TGF-β biology across the cycle of mammary development and differentiation. Early loss of TGF-β growth regulation in breast cancer evolves into fundamental deregulation that mediates cell interactions and phenotypes driving invasive disease. Two outstanding issues are to understand the mechanisms of biological control in situ and the circumstances by which TGF-β regulation is subverted in neoplastic progression.
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Affiliation(s)
- Harold Moses
- Department of Cancer Biology and Department of Medicine, Vanderbilt-Ingram Cancer Center, Vanderbilt University, Nashville, Tennessee 37232, USA
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Cooperation of cancer stem cell properties and epithelial-mesenchymal transition in the establishment of breast cancer metastasis. JOURNAL OF ONCOLOGY 2010; 2011:591427. [PMID: 21253528 PMCID: PMC3021841 DOI: 10.1155/2011/591427] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 09/01/2010] [Revised: 11/09/2010] [Accepted: 12/02/2010] [Indexed: 01/05/2023]
Abstract
Epithelial-mesenchymal transition (EMT) is a multistep process in which cells acquire molecular alterations such as loss of cell-cell junctions and restructuring of the cytoskeleton. There is an increasing understanding that this process may promote breast cancer progression through promotion of invasive and metastatic tumor growth. Recent observations imply that there may be a cross-talk between EMT and cancer stem cell properties, leading to enhanced tumorigenicity and the capacity to generate heterogeneous tumor cell populations. Here, we review the experimental and clinical evidence for the involvement of EMT in cancer stem cell theory, focusing on the common characteristics of this phenomenon.
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CdGAP is required for transforming growth factor β- and Neu/ErbB-2-induced breast cancer cell motility and invasion. Oncogene 2010; 30:1032-45. [PMID: 21042277 DOI: 10.1038/onc.2010.477] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
RhoA, Rac1 and Cdc42, the best-characterized members of the Rho family of small GTPases, are critical regulators of many cellular activities. Cdc42 GTPase-activating protein (CdGAP) is a serine- and proline-rich RhoGAP protein showing GAP activity against both Cdc42 and Rac1 but not RhoA. CdGAP is phosphorylated downstream of the MEK-ERK (extracellular signal-regulated kinase) pathway in response to serum and is required for normal cell spreading and polarized lamellipodia formation. In this study, we found that CdGAP protein and mRNA levels are highly increased in mammary tumor explants expressing an activated Neu/ErbB-2 (Neu-NT) receptor. In response to transforming growth factor-β (TGFβ) stimulation, Neu-NT-expressing mammary tumor explants demonstrate a clear induction in cell motility and invasion. We show that downregulation of CdGAP expression by small interfering RNA abrogates the ability of TGFβ to induce cell motility and invasion of Neu-NT-expressing mammary tumor explants. However, it has no effect on TGFβ-mediated cell adhesion on type 1 collagen and fibronectin. Interestingly, protein expression of E-Cadherin is highly increased in Neu-NT-expressing mammary tumor explants depleted of CdGAP. In addition, complete loss of E-Cadherin expression is not observed in CdGAP-depleted cells during TGFβ-mediated epithelial to mesenchymal transition. Downregulation of the CdGAP expression also decreases cell proliferation of Neu-NT-expressing mammary tumor explants independently of TGFβ. Rescue analysis using re-expression of various CdGAP deletion-mutant proteins revealed that the proline-rich domain (PRD) but not the GAP domain of CdGAP is essential to mediate TGFβ-induced cell motility and invasion. Finally, we found that TGFβ induces the expression and phosphorylation of CdGAP in mammary epithelial NMuMG cells. Taken together, these studies identify CdGAP as a novel molecular target in TGFβ signaling and implicate CdGAP as an essential component in the synergistic interaction between TGFβ and Neu/ErbB-2 signaling pathways in breast cancer cells.
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Bauer JA, Ye F, Marshall CB, Lehmann BD, Pendleton CS, Shyr Y, Arteaga CL, Pietenpol JA. RNA interference (RNAi) screening approach identifies agents that enhance paclitaxel activity in breast cancer cells. Breast Cancer Res 2010; 12:R41. [PMID: 20576088 PMCID: PMC2917036 DOI: 10.1186/bcr2595] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2010] [Revised: 06/04/2010] [Accepted: 06/24/2010] [Indexed: 12/31/2022] Open
Abstract
Introduction Paclitaxel is a widely used drug in the treatment of patients with locally advanced and metastatic breast cancer. However, only a small portion of patients have a complete response to paclitaxel-based chemotherapy, and many patients are resistant. Strategies that increase sensitivity and limit resistance to paclitaxel would be of clinical use, especially for patients with triple-negative breast cancer (TNBC). Methods We generated a gene set from overlay of the druggable genome and a collection of genomically deregulated gene transcripts in breast cancer. We used loss-of-function RNA interference (RNAi) to identify gene products in this set that, when targeted, increase paclitaxel sensitivity. Pharmacological agents that targeted the top scoring hits/genes from our RNAi screens were used in combination with paclitaxel, and the effects on the growth of various breast cancer cell lines were determined. Results RNAi screens performed herein were validated by identification of genes in pathways that, when previously targeted, enhanced paclitaxel sensitivity in the pre-clinical and clinical settings. When chemical inhibitors, CCT007093 and mithramycin, against two top hits in our screen, PPMID and SP1, respectively, were used in combination with paclitaxel, we observed synergistic growth inhibition in both 2D and 3D breast cancer cell cultures. The transforming growth factor beta (TGFβ) receptor inhibitor, LY2109761, that targets the signaling pathway of another top scoring hit, TGFβ1, was synergistic with paclitaxel when used in combination on select breast cancer cell lines grown in 3D culture. We also determined the relative paclitaxel sensitivity of 22 TNBC cell lines and identified 18 drug-sensitive and four drug-resistant cell lines. Of significance, we found that both CCT007093 and mithramycin, when used in combination with paclitaxel, resulted in synergistic inhibition of the four paclitaxel-resistant TNBC cell lines. Conclusions RNAi screening can identify druggable targets and novel drug combinations that can sensitize breast cancer cells to paclitaxel. This genomic-based approach can be applied to a multitude of tumor-derived cell lines and drug treatments to generate requisite pre-clinical data for new drug combination therapies to pursue in clinical investigations.
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Affiliation(s)
- Joshua A Bauer
- Department of Biochemistry, Vanderbilt-Ingram Cancer Center, Vanderbilt University School of Medicine, 2200 Pierce Avenue, Nashville, TN 37232, USA.
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Micalizzi DS, Farabaugh SM, Ford HL. Epithelial-mesenchymal transition in cancer: parallels between normal development and tumor progression. J Mammary Gland Biol Neoplasia 2010; 15:117-34. [PMID: 20490631 PMCID: PMC2886089 DOI: 10.1007/s10911-010-9178-9] [Citation(s) in RCA: 719] [Impact Index Per Article: 51.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2010] [Accepted: 04/26/2010] [Indexed: 02/07/2023] Open
Abstract
From the earliest stages of embryonic development, cells of epithelial and mesenchymal origin contribute to the structure and function of developing organs. However, these phenotypes are not always permanent, and instead, under the appropriate conditions, epithelial and mesenchymal cells convert between these two phenotypes. These processes, termed Epithelial-Mesenchymal Transition (EMT), or the reverse Mesenchymal-Epithelial Transition (MET), are required for complex body patterning and morphogenesis. In addition, epithelial plasticity and the acquisition of invasive properties without the full commitment to a mesenchymal phenotype are critical in development, particularly during branching morphogenesis in the mammary gland. Recent work in cancer has identified an analogous plasticity of cellular phenotypes whereby epithelial cancer cells acquire mesenchymal features that permit escape from the primary tumor. Because local invasion is thought to be a necessary first step in metastatic dissemination, EMT and epithelial plasticity are hypothesized to contribute to tumor progression. Similarities between developmental and oncogenic EMT have led to the identification of common contributing pathways, suggesting that the reactivation of developmental pathways in breast and other cancers contributes to tumor progression. For example, developmental EMT regulators including Snail/Slug, Twist, Six1, and Cripto, along with developmental signaling pathways including TGF-beta and Wnt/beta-catenin, are misexpressed in breast cancer and correlate with poor clinical outcomes. This review focuses on the parallels between epithelial plasticity/EMT in the mammary gland and other organs during development, and on a selection of developmental EMT regulators that are misexpressed specifically during breast cancer.
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Affiliation(s)
- Douglas S. Micalizzi
- Department of Obstetrics and Gynecology, University of Colorado School of Medicine, Aurora, CO 80045 USA
- Medical Scientist Training Program, University of Colorado School of Medicine, Aurora, CO 80045 USA
| | - Susan M. Farabaugh
- Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Aurora, CO 80045 USA
| | - Heide L. Ford
- Department of Obstetrics and Gynecology, University of Colorado School of Medicine, Aurora, CO 80045 USA
- Medical Scientist Training Program, University of Colorado School of Medicine, Aurora, CO 80045 USA
- Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Aurora, CO 80045 USA
- Program in Molecular Biology, University of Colorado School of Medicine, Aurora, CO 80045 USA
- University of Colorado at Denver, Anschutz Medical Campus, RC1 North, Rm. 5102, Aurora, CO 80045 USA
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Abstract
The histologic distinction between bronchioloalveolar carcinoma and other adenocarcinomas is tissue invasion. The clinical importance of lung adenocarcinoma invasion is supported by several recent studies indicating that the risk of death in nonmucinous bronchioloalveolar carcinoma is significantly lower than that of pure invasive tumors and in tumors with greater than 0.5 cm of fibrosis or linear invasion. Using microarray gene expression profiling of human tumors, dysregulation of transforming growth factor-beta signaling was identified as an important mediator of tumor invasion. Subsequent studies showed that the CC chemokine regulated on activation, normal T cell expressed, and presumably secreted was up-regulated in invasive tumors and was required for invasion in cells with repressed levels of the transforming growth factor-beta type II receptor. Taken together, these studies illustrate how information gained from global expression profiling of tumors can be used to identify key pathways and genes mediating tumor growth, invasion, and metastasis.
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Jahchan NS, You YH, Muller WJ, Luo K. Transforming growth factor-beta regulator SnoN modulates mammary gland branching morphogenesis, postlactational involution, and mammary tumorigenesis. Cancer Res 2010; 70:4204-13. [PMID: 20460516 DOI: 10.1158/0008-5472.can-10-0135] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
SnoN is an important negative regulator of transforming growth factor-beta (TGF-beta) signaling that was originally identified as a transforming oncogene in chicken embryonic fibroblasts. Both pro-oncogenic and antioncogenic activities of SnoN have been reported, but its function in normal epithelial cells has not been defined. In the mouse mammary gland, SnoN is expressed at relatively low levels, but it is transiently upregulated at late gestation before being downregulated during lactation and early involution. To assess the effects of elevated levels of SnoN, we generated transgenic mice expressing a SnoN fragment under the control of the mouse mammary tumor virus promoter. In this model system, SnoN elevation increased side-branching and lobular-alveolar proliferation in virgin glands, while accelerating involution in postlactation glands. Increased proliferation stimulated by SnoN was insufficient to induce mammary tumorigenesis. In contrast, elevated levels of SnoN cooperated with polyoma middle T antigen to accelerate the formation of aggressive multifocal adenocarcinomas and to increase the formation of pulmonary metastases. Our studies define functions of SnoN in mammary epithelial cell proliferation and involution, and provide the first in vivo evidence of a pro-oncogenic role for SnoN in mammalian tumorigenesis.
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Affiliation(s)
- Nadine S Jahchan
- Department of Molecular and Cell Biology, University of California, Berkeley, California 94720, USA
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66
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Doxorubicin in combination with a small TGFbeta inhibitor: a potential novel therapy for metastatic breast cancer in mouse models. PLoS One 2010; 5:e10365. [PMID: 20442777 PMCID: PMC2860989 DOI: 10.1371/journal.pone.0010365] [Citation(s) in RCA: 152] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2009] [Accepted: 04/01/2010] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Recent studies suggested that induction of epithelial-mesenchymal transition (EMT) might confer both metastatic and self-renewal properties to breast tumor cells resulting in drug resistance and tumor recurrence. TGFbeta is a potent inducer of EMT and has been shown to promote tumor progression in various breast cancer cell and animal models. PRINCIPAL FINDINGS We report that chemotherapeutic drug doxorubicin activates TGFbeta signaling in human and murine breast cancer cells. Doxorubicin induced EMT, promoted invasion and enhanced generation of cells with stem cell phenotype in murine 4T1 breast cancer cells in vitro, which were significantly inhibited by a TGFbeta type I receptor kinase inhibitor (TbetaRI-KI). We investigated the potential synergistic anti-tumor activity of TbetaR1-KI in combination with doxorubicin in animal models of metastatic breast cancer. Combination of Doxorubicin and TbetaRI-KI enhanced the efficacy of doxorubicin in reducing tumor growth and lung metastasis in the 4T1 orthotopic xenograft model in comparison to single treatments. Doxorubicin treatment alone enhanced metastasis to lung in the human breast cancer MDA-MB-231 orthotopic xenograft model and metastasis to bone in the 4T1 orthotopic xenograft model, which was significantly blocked when TbetaR1-KI was administered in combination with doxorubicin. CONCLUSIONS These observations suggest that the adverse activation of TGFbeta pathway by chemotherapeutics in the cancer cells together with elevated TGFbeta levels in tumor microenvironment may lead to EMT and generation of cancer stem cells resulting in the resistance to the chemotherapy. Our results indicate that the combination treatment of doxorubicin with a TGFbeta inhibitor has the potential to reduce the dose and consequently the toxic side-effects of doxorubicin, and improve its efficacy in the inhibition of breast cancer growth and metastasis.
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67
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Nagaraj NS, Datta PK. Targeting the transforming growth factor-beta signaling pathway in human cancer. Expert Opin Investig Drugs 2010; 19:77-91. [PMID: 20001556 DOI: 10.1517/13543780903382609] [Citation(s) in RCA: 200] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The transforming growth factor-ss (TGF-beta) signaling pathway plays a pivotal role in diverse cellular processes. TGF-beta switches its role from a tumor suppressor in normal or dysplastic cells to a tumor promoter in advanced cancers. It is widely believed that the Smad-dependent pathway is involved in TGF-beta tumor-suppressive functions, whereas activation of Smad-independent pathways, coupled with the loss of tumor-suppressor functions of TGF-beta, is important for its pro-oncogenic functions. TGF-beta signaling has been considered a useful therapeutic target. The discovery of oncogenic actions of TGF-beta has generated a great deal of enthusiasm for developing TGF-beta signaling inhibitors for the treatment of cancer. The challenge is to identify the group of patients where targeted tumors are not only refractory to TGF-beta-induced tumor suppressor functions but also responsive to the tumor-promoting effects of TGF-beta. TGF-beta pathway inhibitors, including small and large molecules, have now entered clinical trials. Preclinical studies with these inhibitors have shown promise in a variety of different tumor models. Here, we focus on the mechanisms of signaling and specific targets of the TGF-beta pathway that are critical effectors of tumor progression and invasion. This report also examines the therapeutic intervention of TGF-ss signaling in human cancers.
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Affiliation(s)
- Nagathihalli S Nagaraj
- Vanderbilt University School of Medicine, Vanderbilt-Ingram Cancer Center, Department of Surgery, Nashville, TN 37232, USA
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68
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Micalizzi DS, Ford HL. Epithelial-mesenchymal transition in development and cancer. Future Oncol 2010; 5:1129-43. [PMID: 19852726 DOI: 10.2217/fon.09.94] [Citation(s) in RCA: 99] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The epithelial-mesenchymal transition (EMT) is a critical developmental process from the earliest events of embryogenesis to later morphogenesis and organ formation. EMT contributes to the complex architecture of the embryo by permitting the progression of embryogenesis from a simple single-cell layer epithelium to a complex three-dimensional organism composed of both epithelial and mesenchymal cells. However, in most tissues EMT is a developmentally restricted process and fully differentiated epithelia typically maintain their epithelial phenotype. Recently, elements of EMT, specifically the loss of epithelial markers and the gain of mesenchymal markers, have been observed in pathological states, including epithelial cancers. Analysis of the molecular mechanisms of this oncogenic epithelial plasticity have implicated the inappropriate expression and activation of developmental EMT programs, suggesting that cancer cells may reinstitute properties of developmental EMT including enhanced migration and invasion. Thus, in the context of cancer, an EMT-like process may permit dissemination of tumor cells from the primary tumor into the surrounding stroma, setting the stage for metastatic spread. Consistent with this hypothesis, activation of these developmental EMT programs in human cancer correlates with advanced disease and poor prognosis. This review will focus on the current knowledge regarding developmental EMT pathways that have been implicated in cancer progression.
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Affiliation(s)
- Douglas S Micalizzi
- Program in Molecular Biology, Medical Scientist Training Program, University of Colorado School of Medicine, Aurora CO 80045, USA
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69
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Furuse C, Miguita L, Rosa ACG, Soares AB, Martinez EF, Altemani A, de Araújo VC. Study of growth factors and receptors in carcinoma ex pleomorphic adenoma. J Oral Pathol Med 2010; 39:540-7. [PMID: 20149060 DOI: 10.1111/j.1600-0714.2009.00858.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Carcinoma ex pleomorphic adenoma (CXPA) is a rare malignant salivary gland tumor derived from a pre-existing pleomorphic adenoma. It is a good model to study the evolution of carcinogenesis, starting with in situ areas to frankly invasive carcinoma. Growth factors are associated with several biological and neoplastic processes by transmembrane receptors. In order to investigate, by immunohistochemistry, the expression of some growth factors and its receptors [EGF receptor, fibroblast growth factor, fibroblast growth factor receptor 1, fibroblast growth factor receptor 2, hepatocyte growth factor, c-Met, transforming growth factor (TGF) beta1, TGFbetaR-II and insulin-like growth factor receptor 1] in the progression of CXPA, we have used ten cases of CXPA in several degrees of invasion- intracapsular, minimally and frankly invasive carcinoma- with only epithelial component. Slides were qualitatively and semi-quantitatively evaluated according to the percentage of stained tumor cells from 0 to 3 (0 = less than 10%; 1 = 10-25%; 2 = 25-50%; 3 = more than 50% of cells). Malignant epithelial cells starting with in situ areas showed stronger expression than luminal cells of pleomorphic adenoma for all antibodies. Most of the intracapsular, minimally and frankly invasive CXPA presented score 3. However, score 2 was more evident in the frankly invasive one. In small nests of invasive carcinoma, negative cells were observed probably indicating that the proliferative process is replaced by the invasive mechanism. Altogether this data infers that these factors may contribute to cell proliferation during initial phases of the tumor.
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Affiliation(s)
- Cristiane Furuse
- Department of Oral Pathology, São Leopoldo Mandic Institute and Research Center, Campinas, São Paulo, Brazil
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70
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Strand DW, Franco OE, Basanta D, Anderson ARA, Hayward SW. Perspectives on tissue interactions in development and disease. Curr Mol Med 2010; 10:95-112. [PMID: 20205682 PMCID: PMC4195241 DOI: 10.2174/156652410791065363] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2009] [Accepted: 06/30/2009] [Indexed: 12/20/2022]
Abstract
From the morphogenetic movements of the three germ layers during development to the reactive stromal microenvironment in cancer, tissue interactions are vital to maintaining healthy organ morphologic architecture and function. The stromal compartment is thought to be complicit in tumor progression and, as such, represents an opportune target for disease therapies. However, recent developments in our understanding of the diversity of the stromal compartment and the lack of appropriate models to study its relevance in human disease have limited our further understanding of the role of tissue interactions in tumor progression. The failure any model to fully recapitulate the complexities of systemic biology continue to create a higher imperative for incorporating various perspectives into a broader understanding for the ultimate goal of designing interventional therapies. Understanding this potential, this review examines the biological models used to study stromal-epithelial interactions and includes an attempt to incorporate behavioral terminology to define and mathematically model ecological relationships in stromal-epithelial interactions. In addition, the current attempt to incorporate these diverse ecological perspectives into in silico mathematical models through cross-disciplinary coordination is reviewed, which will provide a fresh perspective on defining cell group behavior and tissue ecology in disease and hopefully lead to the generation of new hypotheses to be empirically validated.
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Affiliation(s)
- D W Strand
- Vanderbilt Prostate Cancer Center, Department of Urologic Surgery, Vanderbilt University Medical Center, AA-1309 Medical Center North, Nashville, TN 37232, USA.
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71
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Transforming growth factor beta (TGF-beta) and inflammation in cancer. Cytokine Growth Factor Rev 2009; 21:49-59. [PMID: 20018551 DOI: 10.1016/j.cytogfr.2009.11.008] [Citation(s) in RCA: 256] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The transforming growth factor beta (TGF-beta) has been studied with regard to the regulation of cell behavior for over three decades. A large body of research has been devoted to the regulation of epithelial cell and derivative carcinoma cell populations in vitro and in vivo. TGF-beta has been shown to inhibit epithelial cell cycle progression and promote apoptosis that together significantly contribute to the tumor suppressive role for TGF-beta during carcinoma initiation and progression. TGF-beta is also able to promote an epithelial to mesenchymal transition that has been associated with increased tumor cell motility, invasion and metastasis. However, it has now been shown that loss of carcinoma cell responsiveness to TGF-beta stimulation can also promote metastasis. Interestingly, enhanced metastasis in the absence of a carcinoma cell response to TGF-beta stimulation has been shown to involve increased chemokine production resulting in recruitment of pro-metastatic myeloid derived suppressor cell (MDSC) populations to the tumor microenvironment at the leading invasive edge. When present, MDSCs enhance angiogenesis, promote immune tolerance and provide matrix degrading enzymes that promote tumor progression and metastasis. Further, the recruitment of MDSC populations in this context likely enhances the classic role for TGF-beta in immune suppression since the MDSCs are an abundant source of TGF-beta production. Importantly, it is now clear that carcinoma-immune cell cross-talk initiated by TGF-beta signaling within the carcinoma cell is a significant determinant worth consideration when designing therapeutic strategies to manage tumor progression and metastasis.
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72
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Hiatt RA, Haslam SZ, Osuch J. The breast cancer and the environment research centers: transdisciplinary research on the role of the environment in breast cancer etiology. ENVIRONMENTAL HEALTH PERSPECTIVES 2009; 117:1814-22. [PMID: 20049199 PMCID: PMC2799453 DOI: 10.1289/ehp.0800120] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2008] [Accepted: 06/16/2009] [Indexed: 05/03/2023]
Abstract
OBJECTIVES We introduce and describe the Breast Cancer and the Environment Research Centers (BCERC), a research network with a transdisciplinary approach to elucidating the role of environmental factors in pubertal development as a window on breast cancer etiology. We describe the organization of four national centers integrated into the BCERC network. DATA SOURCES Investigators use a common conceptual framework based on multiple levels of biologic, behavioral, and social organization across the life span. The approach connects basic biologic studies with rodent models and tissue culture systems, a coordinated multicenter epidemiologic cohort study of prepubertal girls, and the integration of community members of breast cancer advocates as key members of the research team to comprise the network. DATA EXTRACTION Relevant literature is reviewed that describes current knowledge across levels of organization. Individual research questions and hypotheses in BCERC are driven by gaps in our knowledge that are presented at genetic, metabolic, cellular, individual, and environmental (physical and social) levels. DATA SYNTHESIS As data collection on the cohort, animal experiments, and analyses proceed, results will be synthesized through a transdisciplinary approach. CONCLUSION Center investigators are addressing a large number of specific research questions related to early pubertal onset, which is an established risk factor for breast cancer. BCERC research findings aimed at the primary prevention of breast cancer will be disseminated to the scientific community and to the public by breast cancer advocates, who have been integral members of the research process from its inception.
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Affiliation(s)
- Robert A Hiatt
- Helen Diller Family Comprehensive Cancer Center, University of California at San Francisco, San Francisco, California 94107, USA.
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73
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Dehnavi E, Soheili ZS, Samiei S, Ataei Z, Aryan H. The Effect of TGF-β2on MMP-2 Production and Activity in Highly Metastatic Human Bladder Carcinoma Cell Line 5637. Cancer Invest 2009; 27:568-74. [DOI: 10.1080/07357900802620810] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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74
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Imaging transforming growth factor-beta signaling dynamics and therapeutic response in breast cancer bone metastasis. Nat Med 2009; 15:960-6. [PMID: 19597504 DOI: 10.1038/nm.1943] [Citation(s) in RCA: 182] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2008] [Accepted: 02/10/2009] [Indexed: 11/08/2022]
Abstract
Although the transforming growth factor-beta (TGF-beta) pathway has been implicated in breast cancer metastasis, its in vivo dynamics and temporal-spatial involvement in organ-specific metastasis have not been investigated. Here we engineered a xenograft model system with a conditional control of the TGF-beta-SMAD signaling pathway and a dual-luciferase reporter system for tracing both metastatic burden and TGF-beta signaling activity in vivo. Strong TGF-beta signaling in osteolytic bone lesions is suppressed directly by genetic and pharmacological disruption of the TGF-beta-SMAD pathway and indirectly by inhibition of osteoclast function with bisphosphonates. Notably, disruption of TGF-beta signaling early in metastasis can substantially reduce metastasis burden but becomes less effective when bone lesions are well established. Our in vivo system for real-time manipulation and detection of TGF-beta signaling provides a proof of principle for using similar strategies to analyze the in vivo dynamics of other metastasis-associated signaling pathways and will expedite the development and characterization of therapeutic agents.
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75
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Monks J, Henson PM. Differentiation of the mammary epithelial cell during involution: implications for breast cancer. J Mammary Gland Biol Neoplasia 2009; 14:159-70. [PMID: 19408104 DOI: 10.1007/s10911-009-9121-0] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/03/2009] [Accepted: 04/06/2009] [Indexed: 01/31/2023] Open
Abstract
That milk secretion is not the final differentiated state of the mammary alveolar cells is a relatively new concept. Recent work has suggested that secreting, mammary epithelial cells (MECs) have another function to perform before they undergo cell death in the involuting mammary gland. That is, they help in the final clearance and breakdown of their neighboring cells (and likely residual milk as well.) They become, for a short time, amateur phagocytes, or efferocytes, and then are believed to die and be cleared themselves. Although relatively little study has been made of this change in the functional state of the MEC, nevertheless we may speculate from the involution literature, and extend findings from other systems of apoptotic cell clearance, on some of the mechanisms involved. And with the finding that involution may represent a unique susceptibility window for the progression of metastatic breast cancer, we may suggest areas for future research along these lines as well.
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Affiliation(s)
- Jenifer Monks
- Webb Waring Center, University of Colorado, Denver, Anschutz Medical Campus, Aurora, CO 80045, USA.
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76
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Flanders KC, Wakefield LM. Transforming growth factor-(beta)s and mammary gland involution; functional roles and implications for cancer progression. J Mammary Gland Biol Neoplasia 2009; 14:131-44. [PMID: 19396528 PMCID: PMC2797127 DOI: 10.1007/s10911-009-9122-z] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/11/2009] [Accepted: 04/15/2009] [Indexed: 01/07/2023] Open
Abstract
During rodent mammary gland involution there is a dramatic increase in the expression of the transforming growth factor-beta isoform, TGF-beta3. The TGF-betas are multifunctional cytokines which play important roles in wound healing and in carcinogenesis. The responses that are activated in the remodeling of the gland during involution have many similarities with the wound healing process and have been postulated to generate a mammary stroma that provides a microenvironment favoring tumor progression. In this review we will discuss the putative role of TGF-beta during involution, as well as its effects on the mammary microenvironment and possible implications for pregnancy-associated tumorigenesis.
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Affiliation(s)
- Kathleen C Flanders
- Laboratory of Cancer Biology & Genetics, National Cancer Institute, Bethesda, MD 20892, USA.
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77
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Godoy P, Hengstler JG, Ilkavets I, Meyer C, Bachmann A, Müller A, Tuschl G, Mueller SO, Dooley S. Extracellular matrix modulates sensitivity of hepatocytes to fibroblastoid dedifferentiation and transforming growth factor beta-induced apoptosis. Hepatology 2009; 49:2031-43. [PMID: 19274752 DOI: 10.1002/hep.22880] [Citation(s) in RCA: 194] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
UNLABELLED Hepatocytes in culture are a valuable tool to investigate mechanisms involved in the response of the liver to cytokines. However, it is well established that hepatocytes cultured on monolayers of dried stiff collagen dedifferentiate, losing specialized liver functions. In this study, we show that hepatocyte dedifferentiation is a reversible consequence of a specific signaling network constellation triggered by the extracellular matrix. A dried stiff collagen activates focal adhesion kinase (FAK) via Src, leading to activation of the Akt and extracellular signal-regulated kinase (ERK) 1/2 pathways. Akt causes resistance to transforming growth factor beta (TGF-beta)-induced apoptosis by antagonizing p38, whereas ERK1/2 signaling opens the route to epithelial-mesenchymal transition (EMT). Apoptosis resistance is reversible by inhibiting Akt or Src, and EMT can be abrogated by blocking the ERK1/2 pathway. In contrast to stiff collagen, a softer collagen gel does not activate FAK, keeping the hepatocytes in a state where they remain sensitive to TGF-beta-induced apoptosis and do not undergo EMT. In this culture system, inhibition of p38 as well as overexpression of constitutively active Akt causes apoptosis resistance, whereas constitutively active Ras induces EMT. Finally, we show that matrix-induced EMT is reversible by replating cells from dried stiff to soft gel collagen. Our results demonstrate that hepatocyte dedifferentiation in vitro is an active process driven by FAK-mediated Akt and ERK1/2 signaling. This leads to similar functional and morphological alterations as observed for regenerating hepatocytes in vivo and is reversible when Akt and/or ERK1/2 signaling pathways are antagonized. CONCLUSION Hepatocytes can exist in a differentiated and a dedifferentiated state that are reversible and can be switched by manipulating the responsible key factors of the signaling network.
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Affiliation(s)
- Patricio Godoy
- Molecular Alcohol Research in Gastroenterology, Department of Medicine II, Faculty of Medicine at Mannheim, University of Heidelberg, Germany
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78
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Bierie B, Chung CH, Parker JS, Stover DG, Cheng N, Chytil A, Aakre M, Shyr Y, Moses HL. Abrogation of TGF-beta signaling enhances chemokine production and correlates with prognosis in human breast cancer. J Clin Invest 2009; 119:1571-82. [PMID: 19451693 DOI: 10.1172/jci37480] [Citation(s) in RCA: 113] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2008] [Accepted: 03/18/2009] [Indexed: 01/06/2023] Open
Abstract
In human breast cancer, loss of carcinoma cell-specific response to TGF-beta signaling has been linked to poor patient prognosis. However, the mechanisms through which TGF-beta regulates these processes remain largely unknown. In an effort to address this issue, we have now identified gene expression signatures associated with the TGF-beta signaling pathway in human mammary carcinoma cells. The results strongly suggest that TGF-beta signaling mediates intrinsic, stromal-epithelial, and host-tumor interactions during breast cancer progression, at least in part, by regulating basal and oncostatin M-induced CXCL1, CXCL5, and CCL20 chemokine expression. To determine the clinical relevance of our results, we queried our TGF-beta-associated gene expression signatures in 4 human breast cancer data sets containing a total of 1,319 gene expression profiles and associated clinical outcome data. The signature representing complete abrogation of TGF-beta signaling correlated with reduced relapse-free survival in all patients; however, the strongest association was observed in patients with estrogen receptor-positive (ER-positive) tumors, specifically within the luminal A subtype. Together, the results suggest that assessment of TGF-beta signaling pathway status may further stratify the prognosis of ER-positive patients and provide novel therapeutic approaches in the management of breast cancer.
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Affiliation(s)
- Brian Bierie
- Department of Cancer Biology, Vanderbilt University, Nashville, Tennessee, USA
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79
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Wang SE, Xiang B, Zent R, Quaranta V, Pozzi A, Arteaga CL. Transforming growth factor beta induces clustering of HER2 and integrins by activating Src-focal adhesion kinase and receptor association to the cytoskeleton. Cancer Res 2009; 69:475-82. [PMID: 19147560 DOI: 10.1158/0008-5472.can-08-2649] [Citation(s) in RCA: 113] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
It has been proposed that cross talk between integrin and growth factor receptor signaling such as ErbB2 (HER2) is required for activation of downstream effectors and ErbB2-mediated mammary tumorigenesis. Here we show that transforming growth factor beta (TGF-beta) induced focal adhesion kinase (FAK)-dependent clustering of HER2 and integrins alpha(6), beta(1), and beta(4) in HER2-overexpressing mammary epithelial cells without altering the total and surface levels of HER2 receptors. This effect was mediated by ligand-induced epidermal growth factor receptor (EGFR) activation and the subsequent phosphorylation of Src and FAK. We have previously reported that TGF-beta up-regulates EGFR ligand shedding through a mechanism involving the phosphorylation of tumor necrosis factor-alpha-converting enzyme (TACE/ADAM17). Knockdown of TACE, FAK, or integrin alpha(6) by siRNA or inhibition of EGFR or Src by specific inhibitors abrogated TGF-beta-induced receptor clustering and signaling to phosphatidylinositol 3-kinase-Akt. Finally, inhibition of Src-FAK reversed TGF-beta-induced resistance to the therapeutic HER2 inhibitor trastuzumab in HER2-overexpressing breast cancer cells. Taken together, these data suggest that, by activating Src-FAK, TGF-beta integrates ErbB receptor and integrin signaling to induce cell migration and survival during breast cancer progression.
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Affiliation(s)
- Shizhen Emily Wang
- Division of Tumor Cell Biology, Beckman Research Institute of City of Hope, Duarte, California 91010, USA
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80
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Wang SE, Hinow P, Bryce N, Weaver AM, Estrada L, Arteaga CL, Webb GF. A mathematical model quantifies proliferation and motility effects of TGF-β on cancer cells. COMPUTATIONAL AND MATHEMATICAL METHODS IN MEDICINE 2009; 10:71-83. [PMID: 26000030 DOI: 10.1080/17486700802171993] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Transforming growth factor (TGF)-β is known to have properties of both a tumour suppressor and a tumour promoter. While it inhibits cell proliferation, it also increases cell motility and decreases cell-cell adhesion. Coupling mathematical modelling and experiments, we investigate the growth and motility of oncogene-expressing human mammary epithelial cells under exposure to TGF-β. We use a version of the well-known Fisher-Kolmogorov equation, and prescribe a procedure for its parametrisation. We quantify the simultaneous effects of TGF-β to increase the tendency of individual cells and cell clusters to move randomly and to decrease overall population growth. We demonstrate that in experiments with TGF-β treated cells in vitro, TGF-β increases cell motility by a factor of 2 and decreases cell proliferation by a factor of 1/2 in comparison with untreated cells.
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Affiliation(s)
| | - Peter Hinow
- Institute for Mathematics and Its Applications, University of Minnesota, Minneapolis, MN, USA
| | - Nicole Bryce
- Department of Cancer Biology, Vanderbilt University, Nashville, TN, USA
| | - Alissa M Weaver
- Department of Cancer Biology, Vanderbilt University, Nashville, TN, USA
| | - Lourdes Estrada
- Department of Cancer Biology, Vanderbilt University, Nashville, TN, USA
| | - Carlos L Arteaga
- Department of Cancer Biology, Vanderbilt University, Nashville, TN, USA
| | - Glenn F Webb
- Department of Mathematics, Vanderbilt University, Nashville, TN, USA
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81
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Chow JYC, Cabral JA, Chang J, Carethers JM. TGFbeta modulates PTEN expression independently of SMAD signaling for growth proliferation in colon cancer cells. Cancer Biol Ther 2008; 7:1694-9. [PMID: 18769113 DOI: 10.4161/cbt.7.10.6665] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Signaling pathways enabling transforming growth factor-beta (TGFbeta)'s conversion from a tumor suppressor to a tumor promoter are not well characterized. TGFbeta utilizes intracellular SMADs to mediate growth suppression; however, TGFbeta-induced proliferative pathways may become more apparent when SMAD signaling is abrogated. Here, we determined regulation of the tumor suppressor PTEN by TGFbeta utilizing SMAD4-null colon cancer cells. TGFbeta downregulated PTEN mRNA and simultaneously induced growth proliferation. TGFbeta also induced both SMAD2 and SMAD3 nuclear translocation, but only triggered SMAD2-specific transcriptional activity in the absence of SMAD4. Interference of SMAD2 with DN-SMAD2 enhanced TGFbeta-induced cell proliferation, but downregulation of PTEN expression by TGFbeta was unaffected. TGFbeta increased PI3K tyrosine phosphorylation, and inhibition of PI3K pharmacologically or by DN-p85 transfection reversed both TGFbeta-induced PTEN suppression and TGFbeta-induced cell proliferation. Thus, TGFbeta activates PI3K to downregulate PTEN for enhancement of cell proliferation that is independent of SMAD proteins.
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Affiliation(s)
- Jimmy Y C Chow
- Department of Medicine, University of California San Diego, La Jolla, CA 92093-0063, USA
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82
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Tan AR, Alexe G, Reiss M. Transforming growth factor-beta signaling: emerging stem cell target in metastatic breast cancer? Breast Cancer Res Treat 2008; 115:453-95. [PMID: 18841463 DOI: 10.1007/s10549-008-0184-1] [Citation(s) in RCA: 101] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2008] [Accepted: 09/02/2008] [Indexed: 12/24/2022]
Abstract
In most human breast cancers, lowering of TGFbeta receptor- or Smad gene expression combined with increased levels of TGFbetas in the tumor microenvironment is sufficient to abrogate TGFbetas tumor suppressive effects and to induce a mesenchymal, motile and invasive phenotype. In genetic mouse models, TGFbeta signaling suppresses de novo mammary cancer formation but promotes metastasis of tumors that have broken through TGFbeta tumor suppression. In mouse models of "triple-negative" or basal-like breast cancer, treatment with TGFbeta neutralizing antibodies or receptor kinase inhibitors strongly inhibits development of lung- and bone metastases. These TGFbeta antagonists do not significantly affect tumor cell proliferation or apoptosis. Rather, they de-repress anti-tumor immunity, inhibit angiogenesis and reverse the mesenchymal, motile, invasive phenotype characteristic of basal-like and HER2-positive breast cancer cells. Patterns of TGFbeta target genes upregulation in human breast cancers suggest that TGFbeta may drive tumor progression in estrogen-independent cancer, while it mediates a suppressive host cell response in estrogen-dependent luminal cancers. In addition, TGFbeta appears to play a key role in maintaining the mammary epithelial (cancer) stem cell pool, in part by inducing a mesenchymal phenotype, while differentiated, estrogen receptor-positive, luminal cells are unresponsive to TGFbeta because the TGFBR2 receptor gene is transcriptionally silent. These same cells respond to estrogen by downregulating TGFbeta, while antiestrogens act by upregulating TGFbeta. This model predicts that inhibiting TGFbeta signaling should drive the differentiation of mammary stem cells into ductal cells. Consequently, TGFbeta antagonists may convert basal-like or HER2-positive cancers to a more epithelioid, non-proliferating (and, perhaps, non-metastatic) phenotype. Conversely, these agents might antagonize the therapeutic effects of anti-estrogens in estrogen-dependent luminal cancers. These predictions need to be addressed prospectively in clinical trials and should inform the selection of patient populations most likely to benefit from this novel anti-metastatic therapeutic approach.
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Affiliation(s)
- Antoinette R Tan
- Division of Medical Oncology, Department of Internal Medicine, UMDNJ-Robert Wood Johnson Medical School and The Cancer Institute of New Jersey, New Brunswick, NJ 08903, USA
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83
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Marcotte R, Muller WJ. Signal transduction in transgenic mouse models of human breast cancer--implications for human breast cancer. J Mammary Gland Biol Neoplasia 2008; 13:323-35. [PMID: 18651209 DOI: 10.1007/s10911-008-9087-3] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/29/2008] [Accepted: 07/04/2008] [Indexed: 12/31/2022] Open
Abstract
The advent of genetically engineered mouse models (GEMs) of human breast cancer, have provided important insight into molecular basis or human breast cancer. This review will focus on two of the most extensively studied mouse models for human breast cancer involving mammary gland specific expression of the polyoma middle T (PyV MT) antigen and of the ErbB2. In addition, this review will discuss past and recent advances in understanding relative contribution of the signaling pathways in tumor induction and metastasis by these potent mammary oncogenes.
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Affiliation(s)
- Richard Marcotte
- Molecular Oncology Group, Royal Victoria Hospital, room H5.21, 687 Pine Avenue West, Montreal, QC, Canada H3A 1A1
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84
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Neil JR, Johnson KM, Nemenoff RA, Schiemann WP. Cox-2 inactivates Smad signaling and enhances EMT stimulated by TGF-beta through a PGE2-dependent mechanisms. Carcinogenesis 2008; 29:2227-35. [PMID: 18725385 DOI: 10.1093/carcin/bgn202] [Citation(s) in RCA: 128] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Although it is well established that mammary tumorigenesis converts transforming growth factor-beta (TGF-beta) from a tumor suppressor to a tumor promoter, the molecular, cellular and microenvironmental mechanisms underlying the dichotomous nature of TGF-beta in mammary epithelial cells (MECs) remains to be determined definitively. Aberrant upregulation of the inducible cyclooxygenase, Cox-2, occurs frequently in breast cancers and is associated with increasing disease severity and the acquisition of metastasis; however, the impact of Cox-2 expression on normal and malignant MEC response to TGF-beta remains unknown. We show here that TGF-beta induced Cox-2 expression in normal MECs during their acquisition of an epithelial-mesenchymal transition (EMT) phenotype. Moreover, stable Cox-2 expression in normal MECs stimulated their invasion, EMT and anchorage-independent growth and inhibited their activation of Smad2/3 by TGF-beta. Conversely, antagonizing TGF-beta signaling in malignant, metastatic MECs significantly reduced their expression of Cox-2 as well as enhanced their activation of Smad2/3 by TGF-beta. Along these lines, elevated Cox-2 expression elicited prostaglandin E(2) (PGE(2)) production and the autocrine activation of EP receptors, which antagonized Smad2/3 signaling in normal and malignant MECs. Importantly, rendering normal and malignant MECs Cox-2 deficient inhibited their production of PGE(2) and acquisition of an EMT morphology as well as potentiated their nuclear accumulation of Smad2/3 and transcription of plasminogen activator inhibitor-1 and p15 messenger RNA. Collectively, our findings establish Cox-2 as a novel antagonist of Smad2/3 signaling in normal and malignant MECs; they also suggest that chemotherapeutic targeting of Cox-2 may offer new inroads in restoring the tumor-suppressing activities of TGF-beta in malignant, metastatic breast cancers.
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Affiliation(s)
- Jason R Neil
- Department of Pharmacology, University of Colorado Health Sciences Center, Aurora, CO 80045, USA
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85
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Transforming growth factor beta engages TACE and ErbB3 to activate phosphatidylinositol-3 kinase/Akt in ErbB2-overexpressing breast cancer and desensitizes cells to trastuzumab. Mol Cell Biol 2008; 28:5605-20. [PMID: 18625725 DOI: 10.1128/mcb.00787-08] [Citation(s) in RCA: 137] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In HER2-overexpressing mammary epithelial cells, transforming growth factor beta (TGF-beta) activated phosphatidylinositol-3 kinase (PI3K)/Akt and enhanced survival and migration. Treatment with TGF-beta or expression of an activated TGF-beta type I receptor (Alk5 with the mutation T204D [Alk5(T204D)]) induced phosphorylation of TACE/ADAM17 and its translocation to the cell surface, resulting in increased secretion of TGF-alpha, amphiregulin, and heregulin. In turn, these ligands enhanced the association of p85 with ErbB3 and activated PI3K/Akt. RNA interference of TACE or ErbB3 prevented TGF-beta-induced activation of Akt and cell invasiveness. Treatment with TGF-beta or expression of Alk5(T204D) in HER2-overexpressing cells reduced their sensitivity to the HER2 antibody trastuzumab. Inhibition of Alk5, PI3K, TACE, or ErbB3 restored sensitivity to trastuzumab. A gene signature induced by Alk5(T204D) expression correlated with poor clinical outcomes in patients with invasive breast cancer. These results suggest that by acting on ErbB ligand shedding, an excess of TGF-beta may result in (i) conditioning of the tumor microenvironment with growth factors that can engage adjacent stromal and endothelial cells; (ii) potentiation of signaling downstream ErbB receptors, thus contributing to tumor progression and resistance to anti-HER2 therapies; and (iii) poor clinical outcomes in women with breast cancer.
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86
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Abstract
The TGFBeta pathway has recently emerged as a putative therapeutic target against cancer. However, TGFBeta has a complex and dual role in cancer. In normal epithelial cells and early tumours, TGFBeta acts as a tumour suppressor. In contrast, during tumour progression TGFBeta becomes an oncogenic factor inducing proliferation, angiogenesis, invasion and metastasis, as well as suppressing the anti-tumoral immune response. The role of TGFBeta in oncogenesis requires the precise understanding of the TGFBeta pathway in order to design optimal therapeutic approaches and select the patient population that may benefit from an anti-TGFBeta therapy. Here we review the rationale for evaluating TGFBeta signalling inhibitors as cancer therapeutics, and the progress made in the preclinical and clinical testing of anti- TGFBeta compounds.
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Affiliation(s)
- J Seoane
- Vall d'Hebron Research Institute, Barcelona, Spain.
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87
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Bierie B, Stover DG, Abel TW, Chytil A, Gorska AE, Aakre M, Forrester E, Yang L, Wagner KU, Moses HL. Transforming growth factor-beta regulates mammary carcinoma cell survival and interaction with the adjacent microenvironment. Cancer Res 2008; 68:1809-19. [PMID: 18339861 DOI: 10.1158/0008-5472.can-07-5597] [Citation(s) in RCA: 107] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Transforming growth factor (TGF)-beta signaling has been associated with early tumor suppression and late tumor progression; however, many of the mechanisms that mediate these processes are not known. Using Cre/LoxP technology, with the whey acidic protein promoter driving transgenic expression of Cre recombinase (WAP-Cre), we have now ablated the type II TGF-beta receptor (T beta RII) expression specifically within mouse mammary alveolar progenitors. Transgenic expression of the polyoma virus middle T antigen, under control of the mouse mammary tumor virus enhancer/promoter, was used to produce mammary tumors in the absence or presence of Cre (T beta RII((fl/fl);PY) and T beta RII((fl/fl);PY;WC), respectively). The loss of TGF-beta signaling significantly decreased tumor latency and increased the rate of pulmonary metastasis. The loss of TGF-beta signaling was significantly correlated with increased tumor size and enhanced carcinoma cell survival. In addition, we observed significant differences in stromal fibrovascular abundance and composition accompanied by increased recruitment of F4/80(+) cell populations in T beta RII((fl/fl);PY;WC) mice when compared with T beta RII((fl/fl);PY) controls. The recruitment of F4/80(+) cells correlated with increased expression of known inflammatory genes including Cxcl1, Cxcl5, and Ptgs2 (cyclooxygenase-2). Notably, we also identified an enriched K5(+) dNp63(+) cell population in primary T beta RII((fl/fl);PY;WC) tumors and corresponding pulmonary metastases, suggesting that loss of TGF-beta signaling in this subset of carcinoma cells can contribute to metastasis. Together, our current results indicate that loss of TGF-beta signaling in mammary alveolar progenitors may affect tumor initiation, progression, and metastasis through regulation of both intrinsic cell signaling and adjacent stromal-epithelial interactions in vivo.
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Affiliation(s)
- Brian Bierie
- Department of Cancer Biology, Vanderbilt University, Nashville, TN 37232-6838, USA
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88
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Signaling through ShcA is required for transforming growth factor beta- and Neu/ErbB-2-induced breast cancer cell motility and invasion. Mol Cell Biol 2008; 28:3162-76. [PMID: 18332126 DOI: 10.1128/mcb.01734-07] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Cooperation between the Neu/ErbB-2 and transforming growth factor beta (TGF-beta) signaling pathways enhances the invasive and metastatic capabilities of breast cancer cells; however, the underlying mechanisms mediating this synergy have yet to be fully explained. We demonstrate that TGF-beta induces the migration and invasion of mammary tumor explants expressing an activated Neu/ErbB-2 receptor, which requires signaling from autophosphorylation sites located in the C terminus. A systematic analysis of mammary tumor explants expressing Neu/ErbB-2 add-back receptors that couple to distinct signaling molecules has mapped the synergistic effect of TGF-beta-induced motility and invasion to signals emanating from tyrosine residues 1226/1227 and 1253 of Neu/ErbB-2. Given that the ShcA adaptor protein is known to interact with Neu/ErbB-2 through these residues, we investigated the importance of this signaling molecule in TGF-beta-induced cell motility and invasion. The reduction of ShcA expression rendered cells expressing activated Neu/ErbB-2, or add-back receptors signaling specifically through tyrosines 1226/1227 or 1253, unresponsive to TGF-beta-induced motility and invasion. In addition, a dominant-negative form of ShcA, lacking its three known tyrosine phosphorylation sites, completely abrogates the TGF-beta-induced migration and invasion of breast cancer cells expressing activated Neu/ErbB-2. Our results implicate signaling through the ShcA adaptor as a key component in the synergistic interaction between these pathways.
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89
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Van Aarsen LAK, Leone DR, Ho S, Dolinski BM, McCoon PE, LePage DJ, Kelly R, Heaney G, Rayhorn P, Reid C, Simon KJ, Horan GS, Tao N, Gardner HA, Skelly MM, Gown AM, Thomas GJ, Weinreb PH, Fawell SE, Violette SM. Antibody-mediated blockade of integrin alpha v beta 6 inhibits tumor progression in vivo by a transforming growth factor-beta-regulated mechanism. Cancer Res 2008; 68:561-70. [PMID: 18199553 DOI: 10.1158/0008-5472.can-07-2307] [Citation(s) in RCA: 109] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The alpha(v)beta(6) integrin is up-regulated on epithelial malignancies and has been implicated in various aspects of cancer progression. Immunohistochemical analysis of alpha(v)beta(6) expression in 10 human tumor types showed increased expression relative to normal tissues. Squamous carcinomas of the cervix, skin, esophagus, and head and neck exhibited the highest frequency of expression, with positive immunostaining in 92% (n = 46), 84% (n = 49), 68% (n = 56), and 64% (n = 100) of cases, respectively. We studied the role of alpha(v)beta(6) in Detroit 562 human pharyngeal carcinoma cells in vitro and in vivo. Prominent alpha(v)beta(6) expression was detected on tumor xenografts at the tumor-stroma interface resembling the expression on human head and neck carcinomas. Nonetheless, coculturing cells in vitro with matrix proteins did not up-regulate alpha(v)beta(6) expression. Detroit 562 cells showed alpha(v)beta(6)-dependent adhesion and activation of transforming growth factor-beta (TGF-beta) that was inhibited >90% with an alpha(v)beta(6) blocking antibody, 6.3G9. Although both recombinant soluble TGF-beta receptor type-II (rsTGF-beta RII-Fc) and 6.3G9 inhibited TGF-beta-mediated Smad2/3 phosphorylation in vitro, there was no effect on proliferation. Conversely, in vivo, 6.3G9 and rsTGF-beta RII-Fc inhibited xenograft tumor growth by 50% (n = 10, P < 0.05) and >90% (n = 10, P < 0.001), respectively, suggesting a role for the microenvironment in this response. However, stromal collagen and smooth muscle actin content in xenograft sections were unchanged with treatments. Although further studies are required to consolidate in vitro and in vivo results and define the mechanisms of tumor inhibition by alpha(v)beta(6) antibodies, our findings support a role for alpha(v)beta(6) in human cancer and underscore the therapeutic potential of function blocking alpha(v)beta(6) antibodies.
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90
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Yang L, Huang J, Ren X, Gorska AE, Chytil A, Aakre M, Carbone DP, Matrisian LM, Richmond A, Lin PC, Moses HL. Abrogation of TGF beta signaling in mammary carcinomas recruits Gr-1+CD11b+ myeloid cells that promote metastasis. Cancer Cell 2008; 13:23-35. [PMID: 18167337 PMCID: PMC2245859 DOI: 10.1016/j.ccr.2007.12.004] [Citation(s) in RCA: 730] [Impact Index Per Article: 45.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2007] [Revised: 08/06/2007] [Accepted: 12/04/2007] [Indexed: 01/17/2023]
Abstract
Aberrant TGFbeta signaling is common in human cancers and contributes to tumor metastasis. Here, we demonstrate that Gr-1+CD11b+ myeloid cells are recruited into mammary carcinomas with type II TGF beta receptor gene (Tgfbr2) deletion and directly promote tumor metastasis. Gr-1+CD11b+ cells infiltrate into the invasive front of tumor tissues and facilitate tumor cell invasion and metastasis through a process involving metalloproteinase activity. This infiltration of Gr-1+CD11b+ cells also results in increased abundance of TGF beta 1 in tumors with Tgfbr2 deletion. The recruitment of Gr-1+CD11b+ cells into tumors with Tgfbr2 deletion involves two chemokine receptor axes, the SDF-1/CXCR4 and CXCL5/CXCR2 axes. Together, these data indicate that Gr-1+CD11b+ cells contribute to TGFbeta-mediated metastasis through enhancing tumor cell invasion and metastasis.
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Affiliation(s)
- Li Yang
- Department of Cancer Biology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
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91
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Petersen M, Thorikay M, Deckers M, van Dinther M, Grygielko ET, Gellibert F, de Gouville AC, Huet S, ten Dijke P, Laping NJ. Oral administration of GW788388, an inhibitor of TGF-beta type I and II receptor kinases, decreases renal fibrosis. Kidney Int 2007; 73:705-15. [PMID: 18075500 DOI: 10.1038/sj.ki.5002717] [Citation(s) in RCA: 165] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Progressive kidney fibrosis precedes end-stage renal failure in up to a third of patients with diabetes mellitus. Elevated intra-renal transforming growth factor-beta (TGF-beta) is thought to underlie disease progression by promoting deposition of extracellular matrix and epithelial-mesenchymal transition. GW788388 is a new TGF-beta type I receptor inhibitor with a much improved pharmacokinetic profile compared with SB431542. We studied its effect in vitro and found that it inhibited both the TGF-beta type I and type II receptor kinase activities, but not that of the related bone morphogenic protein type II receptor. Further, it blocked TGF-beta-induced Smad activation and target gene expression, while decreasing epithelial-mesenchymal transitions and fibrogenesis. Using db/db mice, which develop diabetic nephropathy, we found that GW788388 given orally for 5 weeks significantly reduced renal fibrosis and decreased the mRNA levels of key mediators of extracellular matrix deposition in kidneys. Our study shows that GW788388 is a potent and selective inhibitor of TGF-beta signalling in vitro and renal fibrosis in vivo.
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Affiliation(s)
- M Petersen
- Department of Molecular Cell Biology, Leiden University Medical Centre, Leiden, The Netherlands
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92
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Mosley JD, Poirier JT, Seachrist DD, Landis MD, Keri RA. Rapamycin inhibits multiple stages of c-Neu/ErbB2 induced tumor progression in a transgenic mouse model of HER2-positive breast cancer. Mol Cancer Ther 2007; 6:2188-97. [PMID: 17699716 PMCID: PMC2562754 DOI: 10.1158/1535-7163.mct-07-0235] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Amplification of the HER2 (ErbB2, c-Neu) proto-oncogene in breast cancer is associated with poor prognosis and high relapse rates. HER2/ErbB2, in conjunction with ErbB3, signals through the Akt/phosphatidylinositol 3-kinase pathway and leads to the activation of mammalian target of rapamycin (mTOR), a critical mRNA translation regulator that controls cell growth. Gene expression analysis of mammary tumors collected from mouse mammary tumor virus-c-Neu transgenic mice revealed that mRNA levels of several mTOR pathway members were either up-regulated (p85/phosphatidylinositol 3-kinase and p70S6 kinase) or down-regulated (eIF-4E-BP1) in a manner expected to enhance signaling through this pathway. Treatment of these mice with the mTOR inhibitor rapamycin caused growth arrest and regression of primary tumors with no evidence of weight loss or generalized toxicity. The treatment effects were due to decreased proliferation, associated with reduced cyclin D1 expression, and increased cell death in primary tumors. Whereas many of the dead epithelial cells had the histopathologic characteristics of ischemic necrosis, rapamycin treatment was not associated with changes in microvascular density or apoptosis. Rapamycin also inhibited cellular proliferation in lung metastases. In summary, data from this preclinical model of ErbB2/Neu-induced breast cancer show that inhibition of the mTOR pathway with rapamycin blocks multiple stages of ErbB2/Neu-induced tumorigenic progression.
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Affiliation(s)
- Jonathan D. Mosley
- Department of Pharmacology, Case Western Reserve University School of Medicine, Cleveland, OH, 44106
| | - John T. Poirier
- Department of Pharmacology, Case Western Reserve University School of Medicine, Cleveland, OH, 44106
| | - Darcie D. Seachrist
- Department of Pharmacology, Case Western Reserve University School of Medicine, Cleveland, OH, 44106
| | - Melissa D. Landis
- Department of Pharmacology, Case Western Reserve University School of Medicine, Cleveland, OH, 44106
| | - Ruth A. Keri
- Department of Pharmacology, Case Western Reserve University School of Medicine, Cleveland, OH, 44106
- Division of General Medical Sciences—Oncology, Case Western Reserve University School of Medicine, Cleveland, OH 44106
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93
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Aigner L, Bogdahn U. TGF-beta in neural stem cells and in tumors of the central nervous system. Cell Tissue Res 2007; 331:225-41. [PMID: 17710437 DOI: 10.1007/s00441-007-0466-7] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2007] [Accepted: 07/04/2007] [Indexed: 10/22/2022]
Abstract
Mechanisms that regulate neural stem cell activity in the adult brain are tightly coordinated. They provide new neurons and glia in regions associated with high cellular and functional plasticity, after injury, or during neurodegeneration. Because of the proliferative and plastic potential of neural stem cells, they are currently thought to escape their physiological control mechanisms and transform to cancer stem cells. Signals provided by proteins of the transforming growth factor (TGF)-beta family might represent a system by which neural stem cells are controlled under physiological conditions but released from this control after transformation to cancer stem cells. TGF-beta is a multifunctional cytokine involved in various physiological and patho-physiological processes of the brain. It is induced in the adult brain after injury or hypoxia and during neurodegeneration when it modulates and dampens inflammatory responses. After injury, although TGF-beta is neuroprotective, it may limit the self-repair of the brain by inhibiting neural stem cell proliferation. Similar to its effect on neural stem cells, TGF-beta reveals anti-proliferative control on most cell types; however, paradoxically, many brain tumors escape from TGF-beta control. Moreover, brain tumors develop mechanisms that change the anti-proliferative influence of TGF-beta into oncogenic cues, mainly by orchestrating a multitude of TGF-beta-mediated effects upon matrix, migration and invasion, angiogenesis, and, most importantly, immune escape mechanisms. Thus, TGF-beta is involved in tumor progression. This review focuses on TGF-beta and its role in the regulation and control of neural and of brain-cancer stem cells.
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Affiliation(s)
- Ludwig Aigner
- Department of Neurology, University of Regensburg, Universitätsstrasse 84, 93053, Regensburg, Germany.
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94
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Sebestyén A, Hajdu M, Kis L, Barna G, Kopper L. Smad4-independent, PP2A-dependent apoptotic effect of exogenous transforming growth factor beta 1 in lymphoma cells. Exp Cell Res 2007; 313:3167-74. [PMID: 17643425 DOI: 10.1016/j.yexcr.2007.05.028] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2006] [Revised: 04/10/2007] [Accepted: 05/30/2007] [Indexed: 11/20/2022]
Abstract
B-lymphoid tumor cells are often less sensitive than their normal counterparts or insensitive to transforming growth factor beta1 (TGFb) effects. We studied the apoptotic effect of exogenous TGFb in B-lymphoma cells, focusing on the activity and the role of Smad and protein phosphatase/kinase signals. Recombinant TGFb treatment and Smad4 siRNA transfection were used in HT58 B-NHL lymphoma cells in vitro. Gene expression and apoptosis were detected by RT-PCR, Western blot analysis and flow cytometry. The role of MEK1 kinase and PP2A activity--measured with a phosphatase assay--were assessed with the help of specific inhibitors. Smad4 siRNA treatment completely abolished TGFb-induced early gene upregulation, indicating the absence of the rapid activation of Smad signaling. Moreover, functional inhibition of Smad4 had no influence on TGFb-induced apoptosis, but it was dependent on PP2A phosphatase activation, ERK1/2 and JNK inactivation in lymphoma cells. The results prove that exogenous TGFb uses Smad4-independent, alternative (PP2A/PP2A-like dependent) signaling pathways for apoptosis induction in lymphoma cells. Further studies are needed to clarify the possible role and involvement of Smad4-independent effects of TGFb in normal and malignant lymphoid cells and in cells of the tumor microenvironment.
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Affiliation(s)
- Anna Sebestyén
- Semmelweis University, I. Department of Pathology and Experimental Cancer Research, 1085 Budapest, Ulloi út 26, Hungary.
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95
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Ursini-Siegel J, Schade B, Cardiff RD, Muller WJ. Insights from transgenic mouse models of ERBB2-induced breast cancer. Nat Rev Cancer 2007; 7:389-97. [PMID: 17446858 DOI: 10.1038/nrc2127] [Citation(s) in RCA: 191] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
One-third of patients with breast cancer overexpress the ERBB2 receptor tyrosine kinase, which is associated not only with a more aggressive phenotype but also reduced responsiveness to hormonal therapies. Over the past two decades, many ERBB2 mouse models for breast cancer have conclusively shown that this receptor has a causal role in breast cancer development. These mouse models have also enabled the mechanisms controlling tumour growth, angiogenesis, metastasis, dormancy and recurrence in ERBB2-positive breast cancer to be elucidated. In addition, a mouse model has recently been described that accurately recapitulates many of the hallmarks associated with the early stages of the human disease.
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Affiliation(s)
- Josie Ursini-Siegel
- Departments of Medicine and Biochemistry, McGill University, Montreal, Quebec, Canada
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96
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Biswas S, Guix M, Rinehart C, Dugger TC, Chytil A, Moses HL, Freeman ML, Arteaga CL. Inhibition of TGF-beta with neutralizing antibodies prevents radiation-induced acceleration of metastatic cancer progression. J Clin Invest 2007; 117:1305-13. [PMID: 17415413 PMCID: PMC1838926 DOI: 10.1172/jci30740] [Citation(s) in RCA: 280] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2006] [Accepted: 02/06/2007] [Indexed: 01/10/2023] Open
Abstract
We investigated whether TGF-beta induced by anticancer therapies accelerates tumor progression. Using the MMTV/PyVmT transgenic model of metastatic breast cancer, we show that administration of ionizing radiation or doxorubicin caused increased circulating levels of TGF-beta1 as well as increased circulating tumor cells and lung metastases. These effects were abrogated by administration of a neutralizing pan-TGF-beta antibody. Circulating polyomavirus middle T antigen-expressing tumor cells did not grow ex vivo in the presence of the TGF-beta antibody, suggesting autocrine TGF-beta is a survival signal in these cells. Radiation failed to enhance lung metastases in mice bearing tumors that lack the type II TGF-beta receptor, suggesting that the increase in metastases was due, at least in part, to a direct effect of TGF-beta on the cancer cells. These data implicate TGF-beta induced by anticancer therapy as a pro-metastatic signal in tumor cells and provide a rationale for the simultaneous use of these therapies in combination with TGF-beta inhibitors.
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MESH Headings
- Animals
- Antibodies, Blocking/therapeutic use
- Antigens, Polyomavirus Transforming/physiology
- Cell Line, Tumor
- Female
- Humans
- Lung Neoplasms/immunology
- Lung Neoplasms/prevention & control
- Lung Neoplasms/secondary
- Mammary Neoplasms, Experimental/immunology
- Mammary Neoplasms, Experimental/therapy
- Mammary Tumor Virus, Mouse/physiology
- Mice
- Mice, Transgenic
- Neoplasms, Radiation-Induced/immunology
- Neoplasms, Radiation-Induced/pathology
- Neoplasms, Radiation-Induced/prevention & control
- Neoplastic Cells, Circulating/immunology
- Neoplastic Cells, Circulating/pathology
- Retroviridae Infections/pathology
- Retroviridae Infections/prevention & control
- Signal Transduction/physiology
- Transforming Growth Factor beta/antagonists & inhibitors
- Transforming Growth Factor beta/immunology
- Tumor Virus Infections/pathology
- Tumor Virus Infections/prevention & control
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Affiliation(s)
- Swati Biswas
- Department of Cancer Biology,
Department of Medicine,
Department of Pathology,
Breast Cancer Research Program, Vanderbilt-Ingram Cancer Center, and
Department of Radiation Oncology, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Marta Guix
- Department of Cancer Biology,
Department of Medicine,
Department of Pathology,
Breast Cancer Research Program, Vanderbilt-Ingram Cancer Center, and
Department of Radiation Oncology, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Cammie Rinehart
- Department of Cancer Biology,
Department of Medicine,
Department of Pathology,
Breast Cancer Research Program, Vanderbilt-Ingram Cancer Center, and
Department of Radiation Oncology, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Teresa C. Dugger
- Department of Cancer Biology,
Department of Medicine,
Department of Pathology,
Breast Cancer Research Program, Vanderbilt-Ingram Cancer Center, and
Department of Radiation Oncology, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Anna Chytil
- Department of Cancer Biology,
Department of Medicine,
Department of Pathology,
Breast Cancer Research Program, Vanderbilt-Ingram Cancer Center, and
Department of Radiation Oncology, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Harold L. Moses
- Department of Cancer Biology,
Department of Medicine,
Department of Pathology,
Breast Cancer Research Program, Vanderbilt-Ingram Cancer Center, and
Department of Radiation Oncology, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Michael L. Freeman
- Department of Cancer Biology,
Department of Medicine,
Department of Pathology,
Breast Cancer Research Program, Vanderbilt-Ingram Cancer Center, and
Department of Radiation Oncology, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Carlos L. Arteaga
- Department of Cancer Biology,
Department of Medicine,
Department of Pathology,
Breast Cancer Research Program, Vanderbilt-Ingram Cancer Center, and
Department of Radiation Oncology, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
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97
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Suzuki E, Kim S, Cheung HK, Corbley MJ, Zhang X, Sun L, Shan F, Singh J, Lee WC, Albelda SM, Ling LE. A Novel Small-Molecule Inhibitor of Transforming Growth Factor β Type I Receptor Kinase (SM16) Inhibits Murine Mesothelioma Tumor Growth In vivo and Prevents Tumor Recurrence after Surgical Resection. Cancer Res 2007; 67:2351-9. [PMID: 17332368 DOI: 10.1158/0008-5472.can-06-2389] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Malignant mesothelioma is an aggressive and lethal pleural cancer that overexpresses transforming growth factor beta (TGFbeta). We investigated the efficacy of a novel small-molecule TGFbeta type I receptor (ALK5) kinase inhibitor, SM16, in the AB12 syngeneic model of malignant mesothelioma. SM16 inhibited TGFbeta signaling seen as decreased phosphorylated Smad2/3 levels in cultured AB12 cells (IC(50), approximately 200 nmol/L). SM16 penetrated tumor cells in vivo, suppressing tumor phosphorylated Smad2/3 levels for at least 3 h following treatment of tumor-bearing mice with a single i.p. bolus of 20 mg/kg SM16. The growth of established AB12 tumors was significantly inhibited by 5 mg/kg/d SM16 (P < 0.001) delivered via s.c. miniosmotic pumps over 28 days. The efficacy of SM16 was a result of a CD8+ antitumor response because (a) the antitumor effects were markedly diminished in severe combined immunodeficient mice and (b) CD8+ T cells isolated from spleens of mice treated with SM16 showed strong antitumor cytolytic effects whereas CD8+ T cells isolated from spleens of tumor-bearing mice treated with control vehicle showed minimal activity. Treatment of mice bearing large tumors with 5 mg/kg/d SM16 after debulking surgery reduced the extent of tumor recurrence from 80% to <20% (P < 0.05). SM16 was also highly effective in blocking and regressing tumors when given p.o. at doses of 0.45 or 0.65 g/kg in mouse chow. Thus, SM16 shows potent activity against established AB12 malignant mesothelioma tumors using an immune-mediated mechanism and can significantly prevent tumor recurrence after resection of bulky AB12 malignant mesothelioma tumors. These data suggest that ALK5 inhibitors, such as SM16, offer significant potential for the treatment of malignant mesothelioma and possibly other cancers.
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Affiliation(s)
- Eiji Suzuki
- Thoracic Oncology Research Laboratory, University of Pennsylvania, 421 Curie Boulevard, Philadelphia, PA 19104, USA
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98
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Wang SE, Narasanna A, Whitell CW, Wu FY, Friedman DB, Arteaga CL. Convergence of p53 and transforming growth factor beta (TGFbeta) signaling on activating expression of the tumor suppressor gene maspin in mammary epithelial cells. J Biol Chem 2007; 282:5661-9. [PMID: 17204482 PMCID: PMC4015524 DOI: 10.1074/jbc.m608499200] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Using two-dimensional difference gel electrophoresis, we identified the tumor suppressor gene maspin as a transforming growth factor beta (TGFbeta) target gene in human mammary epithelial cells. TGFbeta up-regulatesMaspin expression both at the RNA and protein levels. This up-regulation required Smad2/3 function and intact p53-binding elements in the Maspin promoter. DNA affinity immunoblot and chromatin immunoprecipitation revealed the presence of both Smads and p53 at the Maspin promoter in TGFbeta-treated cells, suggesting that both transcription factors cooperate to induce Maspin transcription. TGFbeta did not activate Maspin-luciferase reporter in p53-mutant MDA-MB-231 breast cancer cells, which exhibit methylation of the endogenous Maspin promoter. Expression of ectopic p53, however, restored ligand-induced association of Smad2/3 with a transfected Maspin promoter. Stable transfection of Maspin inhibited basal and TGFbeta-stimulated MDA-MB-231 cell motility. Finally, knockdown of endogenous Maspin in p53 wild-type MCF10A/HER2 cells enhanced basal and TGFbeta-stimulated motility. Taken together, these data support cooperation between the p53 and TGFbeta tumor suppressor pathways in the induction of Maspin expression, thus leading to inhibition of cell migration.
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Affiliation(s)
- Shizhen Emily Wang
- Department of Cancer Biology, Vanderbilt-Ingram Comprehensive Cancer Center; Vanderbilt University School of Medicine, Nashville, Tennessee 37232
- Breast Cancer Research Program, Vanderbilt-Ingram Comprehensive Cancer Center; Vanderbilt University School of Medicine, Nashville, Tennessee 37232
| | - Archana Narasanna
- Department of Medicine, Vanderbilt-Ingram Comprehensive Cancer Center; Vanderbilt University School of Medicine, Nashville, Tennessee 37232
| | - Corbin W. Whitell
- Department of Biochemistry, Vanderbilt University School of Medicine, Vanderbilt-Ingram Comprehensive Cancer Center; Nashville, Tennessee 37232
- Mass Spectrometry Research Center, Vanderbilt-Ingram Comprehensive Cancer Center; Vanderbilt University School of Medicine, Nashville, Tennessee 37232
| | - Frederick Y. Wu
- Department of Medicine, Vanderbilt-Ingram Comprehensive Cancer Center; Vanderbilt University School of Medicine, Nashville, Tennessee 37232
| | - David B. Friedman
- Department of Biochemistry, Vanderbilt University School of Medicine, Vanderbilt-Ingram Comprehensive Cancer Center; Nashville, Tennessee 37232
- Mass Spectrometry Research Center, Vanderbilt-Ingram Comprehensive Cancer Center; Vanderbilt University School of Medicine, Nashville, Tennessee 37232
- Breast Cancer Research Program, Vanderbilt-Ingram Comprehensive Cancer Center; Vanderbilt University School of Medicine, Nashville, Tennessee 37232
| | - Carlos L. Arteaga
- Department of Cancer Biology, Vanderbilt-Ingram Comprehensive Cancer Center; Vanderbilt University School of Medicine, Nashville, Tennessee 37232
- Department of Medicine, Vanderbilt-Ingram Comprehensive Cancer Center; Vanderbilt University School of Medicine, Nashville, Tennessee 37232
- Breast Cancer Research Program, Vanderbilt-Ingram Comprehensive Cancer Center; Vanderbilt University School of Medicine, Nashville, Tennessee 37232
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99
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Galliher AJ, Neil JR, Schiemann WP. Role of transforming growth factor-beta in cancer progression. Future Oncol 2007; 2:743-63. [PMID: 17155901 DOI: 10.2217/14796694.2.6.743] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Invasion and metastasis are the most lethal characteristics of cancer and the leading causes of cancer-related death. Transforming growth factor (TGF)-beta is a multifunctional cytokine that normally functions to prevent the uncontrolled proliferation of epithelial, endothelial and hematopoietic cells. Quite dichotomously, however, aberrant genetic or epigenetic events often negate the cytostatic function of TGF-beta in these cells, leading to tumor formation. Once freed from the growth-inhibitory effects of TGF-beta, cancer cells acquire the ability to proliferate, invade and metastasize when stimulated by TGF-beta. A thorough understanding of the molecular mechanisms underlying these paradoxical functions of TGF-beta remains elusive. Here, the authors review the tumor-suppressing and -promoting activities of TGF-beta and discuss the potential use and targeting of the TGF-beta-signaling system to prevent the progression and acquisition of metastatic phenotypes by human malignancies.
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Affiliation(s)
- Amy J Galliher
- University of Colorado Health Sciences Center, Department of Pharmacology, Aurora, Colorado 80045, USA
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100
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Widelitz RB, Veltmaat JM, Mayer JA, Foley J, Chuong CM. Mammary glands and feathers: comparing two skin appendages which help define novel classes during vertebrate evolution. Semin Cell Dev Biol 2007; 18:255-66. [PMID: 17382566 PMCID: PMC4382004 DOI: 10.1016/j.semcdb.2007.02.005] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2006] [Revised: 02/07/2007] [Accepted: 02/09/2007] [Indexed: 02/05/2023]
Abstract
It may appear counter-intuitive to compare feathers and mammary glands. However, through this Evo-Devo analysis, we appreciate how species interact with the environment, requiring different ectodermal organs. Novel ectodermal organs help define evolutionary directions, leading to new organism classes as exemplified by feathers for Aves and mammary glands for Mammals. Here, we review their structure, function, morphogenesis and regenerative cycling. Interestingly, both organs undergo extensive branching for different reasons; feather branching is driven by mechanical advantage while mammary glands nourish young. Besides natural selection, both are regulated by sex hormones and acquired a secondary function for attracting mates, contributing to sexual selection.
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Affiliation(s)
- Randall B Widelitz
- Department of Pathology, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA.
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