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Zhao Q, Zhao R, Song C, Wang H, Rong J, Wang F, Yan L, Song Y, Xie Y. Increased IGFBP7 Expression Correlates with Poor Prognosis and Immune Infiltration in Gastric Cancer. J Cancer 2021; 12:1343-1355. [PMID: 33531979 PMCID: PMC7847654 DOI: 10.7150/jca.50370] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Accepted: 12/04/2020] [Indexed: 12/24/2022] Open
Abstract
Background: Insulin-like growth factor binding protein-7 (IGFBP7) contributes to multiple biological processes in various tumors. However, the role of IGFBP7 in gastric cancer (GC) is still undetermined. The study aims to explore the role of IGFBP7 in GC via an integrated bioinformatics analysis. Methods: IGFBP7 expression levels in GC and its normal gastric tissues were analyzed using multiple databases, including the Tumor Immune Estimation Resource (TIMER), Oncomine, The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases, as well as by our clinical gastric specimens. The methylation analysis was conducted with MEXPRESS, UALCAN and Xena online tools. The survival analysis was conducted using the Kaplan-Meier Plotter and Gene Expression Profiling Interactive Analysis (GEPIA) databases. Coexpressed genes of IGFBP7 were selected with the cBioPortal tool and enrichment analysis was conducted with the clusterProfiler package in R software. Gene set enrichment analysis (GSEA) was performed to explore the IGFBP7-related biological processes involved in GC. Correlations between IGFBP7 and immune cell infiltrates were analyzed using the TIMER database. Results: IGFBP7 expression was significantly upregulated in GC and correlated with stage, grade, tumor status and Helicobacter pylori infection. High IGFBP7 expression and low IGFBP7 methylation levels were significantly associated with short survival of patients with GC. Univariate and multivariate analyses revealed that IGFBP7 was an independent risk factor for GC. The coexpressed genes LHFPL6, SEPTIN4, HSPB2, LAYN and GGT5 predicted unfavorable outcomes of GC. Enrichment analysis showed that the coexpressed genes were involved in extracellular matrix (ECM)-related processes. GSEA indicated that IGFBP7 was positively related to ECM and inflammation-related pathways. TIMER analysis indicated that the mRNA level of IGFBP7 was strongly correlated with genes related to various infiltrating immune cells in GC, especially with gene markers of tumor associated macrophages (TAMs). Conclusions: Increased IGFBP7 expression correlates with poor prognosis and immune cell infiltration in GC, which might be a potential biomarker for the diagnosis of GC.
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Affiliation(s)
- Qiaoyun Zhao
- Department of Gastroenterology, The First Affiliated Hospital of Nanchang University, No.17, Yongwai Zheng Street, Donghu District, Nanchang, 330000, Jiangxi, China
| | - Rulin Zhao
- Department of Gastroenterology, The First Affiliated Hospital of Nanchang University, No.17, Yongwai Zheng Street, Donghu District, Nanchang, 330000, Jiangxi, China
| | - Conghua Song
- Department of Gastroenterology, The First Affiliated Hospital of Nanchang University, No.17, Yongwai Zheng Street, Donghu District, Nanchang, 330000, Jiangxi, China
| | - Huan Wang
- Department of Gastroenterology, The First Affiliated Hospital of Nanchang University, No.17, Yongwai Zheng Street, Donghu District, Nanchang, 330000, Jiangxi, China
| | - Jianfang Rong
- Department of Gastroenterology, The First Affiliated Hospital of Nanchang University, No.17, Yongwai Zheng Street, Donghu District, Nanchang, 330000, Jiangxi, China
| | - Fangfei Wang
- Department of Gastroenterology, The First Affiliated Hospital of Nanchang University, No.17, Yongwai Zheng Street, Donghu District, Nanchang, 330000, Jiangxi, China
| | - Lili Yan
- Laboratory of Biochemistry and Molecular Biology, Jiangxi Institute of Medical Sciences, Nanchang 330000, Jiangxi Province, China
| | - Yanping Song
- Department of Gastroenterology, The First Affiliated Hospital of Nanchang University, No.17, Yongwai Zheng Street, Donghu District, Nanchang, 330000, Jiangxi, China
| | - Yong Xie
- Department of Gastroenterology, The First Affiliated Hospital of Nanchang University, No.17, Yongwai Zheng Street, Donghu District, Nanchang, 330000, Jiangxi, China
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Jin L, Shen F, Weinfeld M, Sergi C. Insulin Growth Factor Binding Protein 7 (IGFBP7)-Related Cancer and IGFBP3 and IGFBP7 Crosstalk. Front Oncol 2020; 10:727. [PMID: 32500027 PMCID: PMC7242731 DOI: 10.3389/fonc.2020.00727] [Citation(s) in RCA: 58] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Accepted: 04/16/2020] [Indexed: 12/17/2022] Open
Abstract
The insulin/insulin-like growth factors (IGFs) have crucial tasks in the growth, differentiation, and proliferation of healthy and pernicious cells. They are involved in coordinated complexes, including receptors, ligands, binding proteins, and proteases. However, the systems can become dysregulated in tumorigenesis. Insulin-like growth factor-binding protein 7 (IGFBP7) is a protein belonging to the IGFBP superfamily (also termed GFBP-related proteins). Numerous studies have provided evidence that IGFBP3 and IGFBP7 are involved in a variety of cancers, including hepatocellular carcinoma (HCC), breast cancer, gastroesophageal cancer, colon cancer, prostate cancer, among many others. Still, very few suggest an interaction between these two molecules. In studying several cancer types in our laboratories, we found that both proteins share some crucial signaling pathways. The objective of this review is to present a comprehensive overview of the relationship between IGFBP7 and cancer, as well as highlighting IGFBP3 crosstalk with IGFBP7 reported in recent studies.
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Affiliation(s)
- Li Jin
- Department of Laboratory Medicine, Shiyan Taihe Hospital, College of Biomedical Engineering, Hubei University of Medicine, Shiyan, China
| | - Fan Shen
- Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, AB, Canada
| | - Michael Weinfeld
- Division of Experimental Oncology, Department of Oncology, Cross Cancer Institute, University of Alberta, Edmonton, AB, Canada
| | - Consolato Sergi
- Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, AB, Canada.,Department of Orthopedics, Tianyou Hospital, Wuhan University of Science and Technology, Wuhan, China.,Key Laboratory of Fermentation Engineering, National "111" Center for Cellular Regulation and Molecular Pharmaceutics, Hubei University of Technology, Wuhan, China.,Stollery Children's Hospital, University Alberta Hospital, Edmonton, AB, Canada
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Gambaro K, Quinn MCJ, Cáceres-Gorriti KY, Shapiro RS, Provencher D, Rahimi K, Mes-Masson AM, Tonin PN. Low levels of IGFBP7 expression in high-grade serous ovarian carcinoma is associated with patient outcome. BMC Cancer 2015; 15:135. [PMID: 25886299 PMCID: PMC4381406 DOI: 10.1186/s12885-015-1138-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Accepted: 02/26/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Insulin-like growth factor binding protein 7 (IGFBP7) has been suggested to act as a tumour suppressor gene in various human cancers, yet its role in epithelial ovarian cancer (EOC) has not yet been investigated. We previously observed that IGFBP7 was one of several genes found significantly upregulated in an EOC cell line model rendered non-tumourigenic as consequence of genetic manipulation. The aim of the present study was to investigate the role of IGFBP7 in high-grade serous ovarian carcinomas (HGSC), the most common type of EOC. METHODS We analysed IGFBP7 gene expression in 11 normal ovarian surface epithelial cells (NOSE), 79 high-grade serous ovarian carcinomas (HGSC), and seven EOC cell lines using a custom gene expression array platform. IGFBP7 mRNA expression profiles were also extracted from publicly available databases. Protein expression was assessed by immunohistochemistry of 175 HGSC and 10 normal fallopian tube samples using tissue microarray and related to disease outcome. We used EOC cells to investigate possible mechanisms of gene inactivation and describe various in vitro growth effects of exposing EOC cell lines to human recombinant IGFBP7 protein and conditioned media. RESULTS All HGSCs exhibited IGFBP7 expression levels that were significantly (p = 0.001) lower than the mean of the expression value of NOSE samples and that of a whole ovary sample. IGFBP7 gene and protein expression were lower in tumourigenic EOC cell lines relative to a non-tumourigenic EOC cell line. None of the EOC cell lines harboured a somatic mutation in IGFBP7, although loss of heterozygosity (LOH) of the IGFBP7 locus and epigenetic methylation silencing of the IGFBP7 promoter was observed in two of the cell lines exhibiting loss of gene/protein expression. In vitro functional assays revealed an alteration of the EOC cell migration capacity. Protein expression analysis of HGSC samples revealed that the large majority of tumour cores (72.6%) showed low or absence of IGFBP7 staining and revealed a significant correlation between IGFBP7 protein expression and a prolonged overall survival (p = 0.044). CONCLUSION The low levels of IGFPB7 in HGSC relative to normal tissues, and association with survival are consistent with a purported role in tumour suppressor pathways.
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Affiliation(s)
- Karen Gambaro
- Department of Human Genetics, McGill University, Montreal, H3A 1B1, Canada. .,Centre de recherche du Centre hospitalier de l'Université de Montréal/Institut du cancer de Montréal, Montreal, H2X 0B9, Canada.
| | - Michael C J Quinn
- Department of Human Genetics, McGill University, Montreal, H3A 1B1, Canada. .,Centre de recherche du Centre hospitalier de l'Université de Montréal/Institut du cancer de Montréal, Montreal, H2X 0B9, Canada.
| | - Katia Y Cáceres-Gorriti
- Centre de recherche du Centre hospitalier de l'Université de Montréal/Institut du cancer de Montréal, Montreal, H2X 0B9, Canada.
| | - Rebecca S Shapiro
- Department of Human Genetics, McGill University, Montreal, H3A 1B1, Canada.
| | - Diane Provencher
- Centre de recherche du Centre hospitalier de l'Université de Montréal/Institut du cancer de Montréal, Montreal, H2X 0B9, Canada. .,Department of Obstetric-Gynecology, Université de Montréal, Montreal, H2L 4M1, Canada.
| | - Kurosh Rahimi
- Department of Pathology, Université de Montréal, Montreal, H3C 3J7, Canada.
| | - Anne-Marie Mes-Masson
- Centre de recherche du Centre hospitalier de l'Université de Montréal/Institut du cancer de Montréal, Montreal, H2X 0B9, Canada. .,Department of Medicine, Université de Montréal, Montreal, H3C 3J7, Canada.
| | - Patricia N Tonin
- Department of Human Genetics, McGill University, Montreal, H3A 1B1, Canada. .,The Research Institute of the McGill University Health Centre, Montreal, H4A 3J1, Canada. .,Department of Medicine, McGill University, Montreal, H3G 1A4, Canada. .,Research Institute of the McGill University Health Centre, 1001 Decarie Boulevard, Site Glen Pavillion Block E, Cancer Research Program E026217 (cubicle E), Montreal, Quebec, H4A 3J1, Canada.
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Dong Y, Wang A. Aberrant DNA methylation in hepatocellular carcinoma tumor suppression (Review). Oncol Lett 2014; 8:963-968. [PMID: 25120642 PMCID: PMC4114628 DOI: 10.3892/ol.2014.2301] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2013] [Accepted: 01/15/2014] [Indexed: 12/18/2022] Open
Abstract
Aberrant DNA methylation leads to altered gene expression, resulting in cancerous features. Numerous tumor suppressor genes are silenced by DNA methylation during hepatocarcinogenesis. Promoter CpG island hypermethylation is an important mechanism for inactivating tumor suppressor genes in hepatocellular carcinoma (HCC). Hypermethylation of CpG islands in the p16 (INK4a) and p15 (INK4b) promoters may increase the risk of developing HCC, particularly hepatitis B virus-related HCC. Environmental factors can lead to geographic variations in the methylation status of CpG islands. Aberrant DNA methylation of CpG islands is catalyzed by DNA methyltransferases (DNMTs). Thus, abnormal variations of DNMTs can contribute to hepatocarcinogenesis. In hepatitis-related HCC, microRNAs participate in hepatocarcinogenesis by directly targeting DNMTs, during which hepatitis B virus X acts as a regulator. DNA methylation may also contribute to HCC tumorigenesis by regulating the cell cycle. Based on the importance of DNA methylation in tumor suppression of HCC, certain DNA methylations may predict the risk of tumor development, tumor staging, patient survival and HCC recurrence.
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Affiliation(s)
- Youhong Dong
- Oncology Department, Xiangyang Hospital Affiliated to Hubei University of Medicine, Xiangyang, Hubei 441000, P.R. China
| | - Anping Wang
- Oncology Department, Xiangyang Hospital Affiliated to Hubei University of Medicine, Xiangyang, Hubei 441000, P.R. China
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Prostate cancer xenografts engineered from 3D precision-porous poly(2-hydroxyethyl methacrylate) hydrogels as models for tumorigenesis and dormancy escape. Biomaterials 2014; 35:8164-74. [PMID: 24942815 DOI: 10.1016/j.biomaterials.2014.04.090] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2014] [Accepted: 04/19/2014] [Indexed: 11/23/2022]
Abstract
Synthetic biomaterial scaffolds show promise for in vitro and in vivo 3D cancer models. Tumors engineered in biomaterial scaffolds have shown evidence of being more physiologically relevant than some traditional preclinical model systems, and synthetic biomaterials provide the added benefit of defined and consistent microenvironmental control. Here, we examine sphere-templated poly(2-hydroxyethyl methacrylate) (pHEMA) scaffolds as the basis for engineering xenografts from multiple human prostate cancer cell lines. pHEMA scaffolds seeded and pre-cultured with tumorigenic M12 cells prior to implantation generated tumors in athymic nude mice, demonstrating the ability of the scaffolds to be used as a synthetic vehicle for xenograft generation. pHEMA scaffolds seeded with LNCaP C4-2 cells, which require Matrigel or stromal cell support for tumor formation, were poorly tumorigenic up to 12 weeks after implantation even when Matrigel was infused into the scaffold, demonstrating a lack of necessary pro-tumorigenic signaling within the scaffolds. Finally, M12mac25 cells, which are ordinarily rendered non-tumorigenic through the expression of the tumor suppressor insulin-like growth factor binding protein 7 (IGFBP7), displayed a tumorigenic response when implanted within porous pHEMA scaffolds. These M12mac25 tumors showed significant macrophage infiltration within the scaffolds driven by the foreign body response to the materials. These findings show the potential for this biomaterials-based model system to be used in the study of prostate cancer tumorigenesis and dormancy escape.
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Cheriyan VT, Wang Y, Muthu M, Jamal S, Chen D, Yang H, Polin LA, Tarca AL, Pass HI, Dou QP, Sharma S, Wali A, Rishi AK. Disulfiram suppresses growth of the malignant pleural mesothelioma cells in part by inducing apoptosis. PLoS One 2014; 9:e93711. [PMID: 24690739 PMCID: PMC3972204 DOI: 10.1371/journal.pone.0093711] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2014] [Accepted: 03/05/2014] [Indexed: 12/17/2022] Open
Abstract
Dithiocarbamate compound Disulfiram (DSF) that binds with copper and functions as an inhibitor of aldehyde dehydrogenase is a Food and Drug Administration approved agent for treatment of alcoholism. Copper complexed DSF (DSF-Cu) also possesses anti-tumor and chemosensitizing properties; however, its molecular mechanisms of action remain unclear. Here we investigated malignant pleural mesothelioma (MPM) suppressive effects of DSF-Cu and the molecular mechanisms involved. DSF-Cu inhibited growth of the murine as well as human MPM cells in part by increasing levels of ubiquitinated proteins. DSF-Cu exposure stimulated apoptosis in MPM cells that involved activation of stress-activated protein kinases (SAPKs) p38 and JNK1/2, caspase-3, and cleavage of poly-(ADP-ribose)-polymerase, as well as increased expression of sulfatase 1 and apoptosis transducing CARP-1/CCAR1 protein. Gene-array based analyses revealed that DSF-Cu suppressed cell growth and metastasis-promoting genes including matrix metallopeptidase 3 and 10. DSF inhibited MPM cell growth and survival by upregulating cell cycle inhibitor p27Kip1, IGFBP7, and inhibitors of NF-κB such as ABIN 1 and 2 and Inhibitory κB (IκB)α and β proteins. DSF-Cu promoted cleavage of vimentin, as well as serine-phosphorylation and lysine-63 linked ubiquitination of podoplanin. Administration of 50 mg/kg DSF-Cu by daily i.p injections inhibited growth of murine MPM cell-derived tumors in vivo. Although podoplanin expression often correlates with metastatic disease and poor prognosis, phosphorylation of serines in cytoplasmic domain of podoplanin has recently been shown to interfere with cellular motility and migration signaling. Post-translational modification of podoplanin and cleavage of vimentin by DSF-Cu underscore a metastasis inhibitory property of this agent and together with our in vivo studies underscore its potential as an anti-MPM agent.
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Affiliation(s)
- Vino T. Cheriyan
- Department of Oncology, Wayne State University, Detroit, Michigan, United States of America
- John D. Dingell VA Medical Center, Detroit, Michigan, United States of America
| | - Ying Wang
- Barbara Ann Karmanos Cancer Institute, Detroit, Michigan, United States of America
- Department of Oncology, Wayne State University, Detroit, Michigan, United States of America
| | - Magesh Muthu
- Department of Oncology, Wayne State University, Detroit, Michigan, United States of America
- John D. Dingell VA Medical Center, Detroit, Michigan, United States of America
| | - Shazia Jamal
- Department of Oncology, Wayne State University, Detroit, Michigan, United States of America
- John D. Dingell VA Medical Center, Detroit, Michigan, United States of America
| | - Di Chen
- Barbara Ann Karmanos Cancer Institute, Detroit, Michigan, United States of America
- Department of Oncology, Wayne State University, Detroit, Michigan, United States of America
| | - Huanjie Yang
- Department of Life Science and Engineering, Harbin Institute of Technology, Harbin, China
| | - Lisa A. Polin
- Barbara Ann Karmanos Cancer Institute, Detroit, Michigan, United States of America
- Department of Oncology, Wayne State University, Detroit, Michigan, United States of America
| | - Adi L. Tarca
- Department of Computer Science, Wayne State University, Detroit, Michigan, United States of America
| | - Harvey I. Pass
- Division of Cardiothoracic Surgery, New York University Cancer Center, New York, New York, United States of America
| | - Q. Ping Dou
- Barbara Ann Karmanos Cancer Institute, Detroit, Michigan, United States of America
- Department of Oncology, Wayne State University, Detroit, Michigan, United States of America
- * E-mail: (QPD); (AKR)
| | - Sunita Sharma
- Barbara Ann Karmanos Cancer Institute, Detroit, Michigan, United States of America
- Department of Oncology, Wayne State University, Detroit, Michigan, United States of America
| | - Anil Wali
- Barbara Ann Karmanos Cancer Institute, Detroit, Michigan, United States of America
- John D. Dingell VA Medical Center, Detroit, Michigan, United States of America
| | - Arun K. Rishi
- Barbara Ann Karmanos Cancer Institute, Detroit, Michigan, United States of America
- Department of Oncology, Wayne State University, Detroit, Michigan, United States of America
- John D. Dingell VA Medical Center, Detroit, Michigan, United States of America
- * E-mail: (QPD); (AKR)
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Akiel M, Rajasekaran D, Gredler R, Siddiq A, Srivastava J, Robertson C, Jariwala NH, Fisher PB, Sarkar D. Emerging role of insulin-like growth factor-binding protein 7 in hepatocellular carcinoma. J Hepatocell Carcinoma 2014; 1:9-19. [PMID: 27508172 PMCID: PMC4918263 DOI: 10.2147/jhc.s44460] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Hepatocellular carcinoma (HCC) is a vicious and highly vascular cancer with a dismal prognosis. It is a life-threatening illness worldwide that ranks fifth in terms of cancer prevalence and third in cancer deaths. Most patients are diagnosed at an advanced stage by which time conventional therapies are no longer effective. Targeted molecular therapies, such as the multikinase inhibitor sorafenib, provide a modest increase in survival for advanced HCC patients and display significant toxicity. Thus, there is an immense need to identify novel regulators of HCC that might be targeted effectively. The insulin-like growth factor (IGF) axis is commonly abnormal in HCC. Upon activation, the IGF axis controls metabolism, tissue homeostasis, and survival. Insulin-like growth factor-binding protein 7 (IGFBP7) is a secreted protein of a family of low-affinity IGF-binding proteins termed “IGFBP-related proteins” that have been identified as a potential tumor suppressor in HCC. IGFBP7 has been implicated in regulating cellular proliferation, senescence, and angiogenesis. In this review, we provide a comprehensive discussion of the role of IGFBP7 in HCC and the potential use of IGFBP7 as a novel biomarker for drug resistance and as an effective therapeutic strategy.
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Affiliation(s)
- Maaged Akiel
- Department of Human and Molecular Genetics, Massey Cancer Center, VCU Institute of Molecular Medicine, Virginia Commonwealth University, Richmond, Virginia, USA
| | - Devaraja Rajasekaran
- Department of Human and Molecular Genetics, Massey Cancer Center, VCU Institute of Molecular Medicine, Virginia Commonwealth University, Richmond, Virginia, USA
| | - Rachel Gredler
- Department of Human and Molecular Genetics, Massey Cancer Center, VCU Institute of Molecular Medicine, Virginia Commonwealth University, Richmond, Virginia, USA
| | - Ayesha Siddiq
- Department of Human and Molecular Genetics, Massey Cancer Center, VCU Institute of Molecular Medicine, Virginia Commonwealth University, Richmond, Virginia, USA
| | - Jyoti Srivastava
- Department of Human and Molecular Genetics, Massey Cancer Center, VCU Institute of Molecular Medicine, Virginia Commonwealth University, Richmond, Virginia, USA
| | - Chadia Robertson
- Department of Human and Molecular Genetics, Massey Cancer Center, VCU Institute of Molecular Medicine, Virginia Commonwealth University, Richmond, Virginia, USA
| | - Nidhi Himanshu Jariwala
- Department of Human and Molecular Genetics, Massey Cancer Center, VCU Institute of Molecular Medicine, Virginia Commonwealth University, Richmond, Virginia, USA
| | - Paul B Fisher
- Department of Human and Molecular Genetics, Massey Cancer Center, VCU Institute of Molecular Medicine, Virginia Commonwealth University, Richmond, Virginia, USA
| | - Devanand Sarkar
- Department of Human and Molecular Genetics, Massey Cancer Center, VCU Institute of Molecular Medicine, Virginia Commonwealth University, Richmond, Virginia, USA
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8
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Zhu S, Xu F, Zhang J, Ruan W, Lai M. Insulin-like growth factor binding protein-related protein 1 and cancer. Clin Chim Acta 2014; 431:23-32. [PMID: 24513543 DOI: 10.1016/j.cca.2014.01.037] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2013] [Revised: 01/23/2014] [Accepted: 01/24/2014] [Indexed: 12/11/2022]
Abstract
Insulin-like growth factor binding protein-related protein 1 (IGFBP-rP1) belongs to the IGFBP family whose members have a conserved structural homology. It has a low affinity for IGFs and a high affinity for insulin, suggesting that IGFBP-rP1 may have a biological function distinct from other members of the family. IGFBP-rP1 is ubiquitously expressed in normal human tissues and has diverse biological functions, regulating cell proliferation, apoptosis and senescence; it may also have a key role in vascular biology. Increasing evidence suggests that IGFBP-rP1 acts as a tumor suppressor. It elicits its biological effects by both insulin/IGF-dependent and -independent mechanisms. This paper provides a brief overview of the structure and regulation of IGFBP-rP1 and its various biological functions in cancer, as well as the underlying molecular mechanisms.
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Affiliation(s)
- Shuzhen Zhu
- Department of Pathology, Zhejiang University School of Medicine, 866 Yuhangtang Road, Hangzhou, 310058 Zhejiang, China; Department of Clinical Laboratory, Qilu Hospital, Shandong University, 107 Wenhuaxi Road, Jinan 250012, China.
| | - Fangying Xu
- Department of Pathology, Zhejiang University School of Medicine, 866 Yuhangtang Road, Hangzhou, 310058 Zhejiang, China.
| | - Jing Zhang
- Department of Pathology, Zhejiang University School of Medicine, 866 Yuhangtang Road, Hangzhou, 310058 Zhejiang, China.
| | - Wenjing Ruan
- Department of Respiratory Diseases, Affiliated Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, 3 Qingchundong Road, Hangzhou 310016, China.
| | - Maode Lai
- Department of Pathology, Zhejiang University School of Medicine, 866 Yuhangtang Road, Hangzhou, 310058 Zhejiang, China.
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9
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Rao C, Lin SL, Ruan WJ, Wen H, Wu DJ, Deng H. High expression of IGFBP7 in fibroblasts induced by colorectal cancer cells is co-regulated by TGF-β and Wnt signaling in a Smad2/3-Dvl2/3-dependent manner. PLoS One 2014; 9:e85340. [PMID: 24427302 PMCID: PMC3888407 DOI: 10.1371/journal.pone.0085340] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2013] [Accepted: 12/04/2013] [Indexed: 01/05/2023] Open
Abstract
Fibroblasts in the tumor microenvironment are a key determinant in cancer progression and may be a promising target for cancer therapy. Insulin-like growth factor binding protein 7 (IGFBP7) is known as a tumor suppressor in colorectal cancer (CRC). The present study investigated the inductive mechanism of IGFBP7 expression in fibroblasts by supernatant from the CRC cell line, SW620. The results showed that the expression of IGFBP7 was up-regulated in the fibroblasts when treated with SW620 supernatant and exogenous TGF-β1. The IGFBP7 induced by SW620 supernatant or TGF-β1 was partially inhibited by the TGF-β1 specific antibody AF and TGF-β1 receptor antagonist SB431542. The Wnt signaling-targeted genes, c-Myc, CCND1 and the proteins Dvl2/3, were all up-regulated in fibroblasts expressing high levels of IGFBP7, and the up-regulation could be inhibited both by the Wnt signaling antagonist Dickkopf-1 (DKK1) and by the TGF-β1 receptor antagonist SB431542. In conclusion, CRC cells promote the high expression of IGFBP7 in fibroblasts, most likely through the co-regulation of TGF-β and Wnt signaling in a Smad2/3-Dvl2/3 dependent manner. Taken together, these data suggest that the fibroblasts could be a novel therapeutic target in tumor therapy.
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Affiliation(s)
- Cui Rao
- Department of Pathology, School of Medicine, Zhejiang University, Hangzhou, P. R. China
| | - Shan-Li Lin
- Department of Pathology, School of Medicine, Zhejiang University, Hangzhou, P. R. China
| | - Wen-Jing Ruan
- Department of Pathology, School of Medicine, Zhejiang University, Hangzhou, P. R. China
| | - Huan Wen
- Department of Pathology, School of Medicine, Zhejiang University, Hangzhou, P. R. China
| | - Dan-Ju Wu
- Department of Pathology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, P. R. China
| | - Hong Deng
- Department of Pathology, School of Medicine, Zhejiang University, Hangzhou, P. R. China
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IGFBP7 is associated with poor prognosis in oesophageal adenocarcinoma and is regulated by promoter DNA methylation. Br J Cancer 2013; 110:775-82. [PMID: 24357797 PMCID: PMC3915137 DOI: 10.1038/bjc.2013.783] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2013] [Revised: 11/22/2013] [Accepted: 11/26/2013] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND We examined whether silencing of IGFBP7 was associated with survival in patients with oesophageal adenocarcinoma. METHODS Protein expression of IGFBP7 was determined using immunohistochemistry in a tissue microarray representing tumours from 65 patients with oesophageal adenocarcinoma who had not had neoadjuvant therapy. DNA methylation of the IGFBP7 promoter was determined with the melt curve analysis in cell lines and patient tissues. RESULTS Expression of IGFBP7 was observed in the oesophageal adenocarcinoma of 34 out of 65 (52%) patients and was associated with significantly reduced median (11 vs 92 months) and 5-year survival (25% vs 52%). Multivariate analysis identified expression as an independent prognostic indicator for survival (hazard ratio=3.24, 95% confidence interval=1.58-6.67, P-value=0.0014). Hypermethylation of IGFBP7 was associated with silencing of gene expression in cell lines and patient tissues (P-value=0.0225). Methylation was observed in the squamous mucosa of 2 out of 15 (13%) patients with Barrett's oesophagus and 3 out of 17 (18%) with oesophageal adenocarcinoma. Methylation was observed in 14 out of 18 (78%) of biopsies of Barrett's mucosa and 23 out of 34 (68%) patients with oesophageal adenocarcinoma. CONCLUSION Reduced IGFBP7 protein expression was associated with longer survival in patients with oesophageal adenocarcinoma. Methylation of the IGFBP7 promoter was associated with silencing of gene expression and was frequent in Barrett's oesophagus and oesophageal adenocarcinoma.
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Streeter EY, Badoer E, Woodman OL, Hart JL. Effect of type 1 diabetes on the production and vasoactivity of hydrogen sulfide in rat middle cerebral arteries. Physiol Rep 2013; 1:e00111. [PMID: 24303182 PMCID: PMC3841046 DOI: 10.1002/phy2.111] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2013] [Revised: 09/07/2013] [Accepted: 09/09/2013] [Indexed: 01/03/2023] Open
Abstract
Hydrogen sulfide (H2S) is produced endogenously in vascular tissue and has both vasoregulation and antioxidant effects. This study examines the effect of diabetes-induced oxidative stress on H2S production and function in rat middle cerebral arteries. Diabetes was induced in rats with streptozotocin (50 mg/kg, i.v.). Middle cerebral artery function was examined using a small vessel myograph and superoxide anion generation measured using nicotinamide adenine dinucleotide phosphate (NADPH)-dependent lucigenin-enhanced chemiluminescence. Cystathionine-γ-lyase (CSE) mRNA expression was measured via RT-PCR. Diabetic rats had elevated blood glucose and significantly reduced cerebral artery endothelial function. Maximum vasorelaxation to the H2S donor NaHS was unaffected in diabetic cerebral arteries and was elicited via a combination of K+, Cl−, and Ca2+ channel modulation, although the contribution of Cl− channels was significantly less in the diabetic cerebral arteries. Vasorelaxation to the H2S precursor l-cysteine and CSE mRNA were significantly increased in diabetic cerebral arteries. Cerebral artery superoxide production was significantly increased in diabetes, but this increase was attenuated ex vivo by incubation with the H2S donor NaHS. These data confirm that cerebral artery endothelial dysfunction and oxidative stress occurs in diabetes. Endogenous H2S production and activity is upregulated in cerebral arteries in this model of diabetes. Vasorelaxation responses to exogenous H2S are preserved and exogenous H2S attenuates the enhanced cerebral artery generated superoxide observed in the diabetic group. These data suggest that upregulation of endogenous H2S in diabetes may play an antioxidant and vasoprotective role.
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Affiliation(s)
- Elosie Y Streeter
- School of Medical Sciences and Health Innovations Research Institute, RMIT University Bundoora, Victoria, 3083, Australia
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12
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Hochberg M, Gilead L, Markel G, Nemlich Y, Feiler Y, Enk CD, Denichenko P, Karni R, Ingber A. Insulin-like growth factor-binding protein-7 (IGFBP7) transcript: A-to-I editing events in normal and cancerous human keratinocytes. Arch Dermatol Res 2013; 305:519-28. [PMID: 23543219 DOI: 10.1007/s00403-013-1338-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2012] [Revised: 03/03/2013] [Accepted: 03/18/2013] [Indexed: 12/20/2022]
Abstract
Non-melanoma skin cancers (NMSC) are the most common malignancies in caucasians worldwide. Insulin-like growth factor-binding protein-7 (IGFBP7) was suggested to function as a tumor suppressor gene in several cancers, and to play a role in the proliferation of keratinocytes. A-to-I RNA editing is a post-transcriptional mechanism frequently used to expand and diversify transcriptome and proteome repertoire in eukaryotic cells. A-to-I RNA editing can alter codons, substitute amino acids and affect protein sequence, structure, and function. Two editing sites were identified within the IGFBP7 transcript. To evaluate the expression and editing of IGFBP7 mRNA in NMSC compared to normal epidermis. We examined the expression and mRNA editing level of IGFBP7 in 22 basal cell carcinoma (BCC), 15 squamous cell carcinoma (SCC), and 18 normal epidermis samples that were surgically removed from patients by the Mohs Micrographic Surgery procedure. We studied the effect of IGFBP7 editing on an immortalized HaCaT keratinocyte cell model. IGFBP7 mRNA is over expressed in BCC and SCC compared to normal epidermis. Moreover, the IGFBP7 transcript is highly edited in normal epidermis, but its editing is significantly reduced in BCC and SCC. The edited form of IGFBP7 can inhibit proliferation and induce senescence in cultured keratinocytes. This study describes for the first time A-to-I editing in the coding sequence of a tumor suppressor gene in humans, and suggests that IGFBP7 editing serves as a fine-tuning mechanism to maintain the equilibrium between proliferation and senescence in normal skin.
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Affiliation(s)
- Malka Hochberg
- Department of Dermatology, Hadassah-Hebrew University Medical Center, P.O.Box 12000, 91010, Jerusalem, Israel.
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13
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Chen D, Yoo BK, Santhekadur PK, Gredler R, Bhutia SK, Das SK, Fuller C, Su ZZ, Fisher PB, Sarkar D. Insulin-like growth factor-binding protein-7 functions as a potential tumor suppressor in hepatocellular carcinoma. Clin Cancer Res 2011; 17:6693-701. [PMID: 21908579 DOI: 10.1158/1078-0432.ccr-10-2774] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
PURPOSE Hepatocellular carcinoma (HCC) is a highly virulent malignancy with no effective treatment, thus requiring innovative and effective targeted therapies. The oncogene astrocyte-elevated gene-1 (AEG-1) plays a seminal role in hepatocarcinogenesis and profoundly downregulates insulin-like growth factor-binding protein-7 (IGFBP7). The present study focuses on analyzing potential tumor suppressor functions of IGFBP7 in HCC and the relevance of IGFBP7 downregulation in mediating AEG-1 function. EXPERIMENTAL DESIGN IGFBP7 expression was detected by immunohistochemistry in HCC tissue microarray and real-time PCR and ELISA in human HCC cell lines. Dual FISH was done to detect LOH at IGFBP7 locus. Stable IGFBP7-overexpressing clones were established in the background of AEG-1-overexpressing human HCC cells and were analyzed for in vitro proliferation and senescence and in vivo tumorigenesis and angiogenesis. RESULTS IGFBP7 expression is significantly downregulated in human HCC samples and cell lines compared with normal liver and hepatocytes, respectively, and inversely correlates with the stages and grades of HCC. Genomic deletion of IGFBP7 was identified in 26% of patients with HCC. Forced overexpression of IGFBP7 in AEG-1-overexpressing HCC cells inhibited in vitro growth and induced senescence, and profoundly suppressed in vivo growth in nude mice that might be an end result of inhibition of angiogenesis by IGFBP7. CONCLUSION The present findings provide evidence that IGFBP7 functions as a novel putative tumor suppressor for HCC and establish the corollary that IGFBP7 downregulation can effectively modify AEG-1 function. Accordingly, targeted overexpression of IGFBP7 might be a potential novel therapy for HCC.
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Affiliation(s)
- Dong Chen
- Department of Pathology, Virginia Commonwealth University, School of Medicine, Richmond, Virginia 23298, USA
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14
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Chen Y, Cui T, Knösel T, Yang L, Zöller K, Petersen I. IGFBP7 is a p53 target gene inactivated in human lung cancer by DNA hypermethylation. Lung Cancer 2010; 73:38-44. [PMID: 21095038 DOI: 10.1016/j.lungcan.2010.10.015] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2010] [Revised: 10/18/2010] [Accepted: 10/25/2010] [Indexed: 10/18/2022]
Abstract
Insulin-like growth factor binding protein 7 (IGFBP7) was considered a tumor suppressor gene in lung cancer. However, the mechanism responsible for the downregulation of this gene has not yet been fully understood. In this study, we analyzed the epigenetic inactivation of IGFBP7 expression in human lung cancer. We found that 14 out of 16 lung cancer cell lines showed decreased expression of IGFBP7 compared to control cells by real-time RT-PCR, and 42 out of 90 patients (46.7%) with primary lung tumor exhibited negative staining of IGFBP7 by immunohistochemistry analysis. The IGFBP7 expression could be restored by demethylation agent 5-aza-2'-deoxycytidine (DAC) in 7 cancer cell lines. Methylation status of IGFBP7 was further evaluated by bisulfite sequencing (BS) and methylation-specific-PCR (MSP). It turned out that low expression of IGFBP7 was associated with DNA methylation in lung cancer cell lines and in primary lung tumors (P=0.019). To explore the regulatory role of p53 on IGFBP7, we transfected a wild type p53 expression vector into lung cancer cell lines H1299, H2228, and H82. Forced expression of p53 increased IGFBP7 expression only in H82 harboring no IGFBP7 methylation, while transfection in combination with DAC induced the expression of IGFBP7 in H1299 and H2228, in which IGFBP7 was methylated. Additionally, treatment with p53 inducer adriamycin (ADR) alone or in combination with DAC increased the expression of IGFBP7 in the 3 cell lines. Our data suggest that IGFBP7 is inactivated in lung cancer by DNA hypermethylation in both lung cancer cell lines and primary lung tumors, and IGFBP7 might be regulated by p53 in lung cancer cells.
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Affiliation(s)
- Yuan Chen
- Institute of Pathology, University Hospital Jena, Ziegelmühlenweg 1, 07743 Jena, Germany
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15
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Heesch S, Bartram I, Neumann M, Reins J, Mossner M, Schlee C, Stroux A, Haferlach T, Goekbuget N, Hoelzer D, Hofmann WK, Thiel E, Baldus CD. Expression of IGFBP7 in acute leukemia is regulated by DNA methylation. Cancer Sci 2010; 102:253-9. [PMID: 21040219 DOI: 10.1111/j.1349-7006.2010.01760.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The important role of insulin-like growth factor binding protein 7 (IGFBP7) as a tumor suppressor in solid tumors has been revealed in several studies. Interestingly, in a recent study IGFBP7 was also shown to be aberrantly expressed in acute leukemia. Moreover, in acute T-lymphoblastic leukemia (T-ALL), high IGFBP7 expression predicts primary therapy resistance. In order to elucidate the mechanisms underlying aberrant IGFBP7 expression, we used pyrosequencing technology to investigate the DNA methylation of IGFBP7 in 109 T-ALL patient samples. Aberrant methylation was shown and hypomethylation was associated with an early immunophenotype and co-expression of the stem cell markers CD117 (P < 0.001) and CD34 (P < 0.001). In concordance, gene expression profiles of 86 T-ALL patients revealed upregulation of stem cell markers (CD34 and CD133) as well as genes associated with poor outcome and pathogenesis of leukemia (MN1, BAALC, FLT3) in the high IGFBP7 expression group. In conclusion, aberrant IGFBP7 expression is regulated by DNA methylation in acute leukemia. Hypomethylation of the gene is likely to characterize an immature and a more malignant subtype of the disease.
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Affiliation(s)
- Sandra Heesch
- Department of Hematology and Oncology, Campus Benjamin Franklin, Charité, University Hospital Berlin, Berlin, Germany
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Ruan W, Zhu S, Wang H, Xu F, Deng H, Ma Y, Lai M. IGFBP-rP1, a potential molecule associated with colon cancer differentiation. Mol Cancer 2010; 9:281. [PMID: 20977730 PMCID: PMC2987981 DOI: 10.1186/1476-4598-9-281] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2010] [Accepted: 10/26/2010] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND In our previous studies, we have demonstrated that insulin-like growth factor binding protein-related protein1 (IGFBP-rP1) played its potential tumor suppressor role in colon cancer cells through apoptosis and senescence induction. In this study, we will further uncover the role of IGFBP-rP1 in colon cancer differentiation and a possible mechanism by revealing responsible genes. RESULTS In normal colon epithelium, immunohistochemistry staining detected a gradient IGFBP-rP1 expression along the axis of the crypt. IGFBP-rP1 strongly expressed in the differentiated cells at the surface of the colon epithelium, while weakly expressed at the crypt base. In colon cancer tissues, the expression of IGFBP-rP1 correlated positively with the differentiation status. IGFBP-rP1 strongly expressed in low grade colorectal carcinoma and weakly expressed in high grade colorectal carcinoma. In vitro, transfection of PcDNA3.1(IGFBP-rP1) into RKO, SW620 and CW2 cells induced a more pronounced anterior-posterior polarity morphology, accompanied by upregulation with alkaline phosphatase (AKP) activity. Upregulation of carcino-embryonic antigen (CEA) was also observed in SW620 and CW2 transfectants. The addition of IGFBP-rP1 protein into the medium could mimic most but not all effects of IGFBP-rP1 cDNA transfection. Seventy-eight reproducibly differentially expressed genes were detected in PcDNA3.1(IGFBP-rP1)-RKO transfectants, using Affymetrix 133 plus 2.0 expression chip platform. Directed Acyclic Graph (DAG) of the enriched GO categories demonstrated that differential expression of the enzyme regulator activity genes together with cytoskeleton and actin binding genes were significant. IGFBP-rP1 could upreguate Transgelin (TAGLN), downregulate SRY (sex determining region Y)-box 9(campomelic dysplasia, autosomal sex-reversal) (SOX9), insulin receptor substrate 1(IRS1), cyclin-dependent kinase inhibitor 2B (p15, inhibits CDK4) (CDKN2B), amphiregulin(schwannoma-derived growth factor) (AREG) and immediate early response 5-like(IER5L) in RKO, SW620 and CW2 colon cancer cells, verified by Real time Reverse Transcription Polymerase Chain Reaction (rtRT-PCR). During sodium butyrate-induced Caco2 cell differentiation, IGFBP-rP1 was upregulated and the expression showed significant correlation with the AKP activity. The downregulation of IRS1 and SOX9 were also induced by sodium butyrate. CONCLUSION IGFBP-rP1 was a potential key molecule associated with colon cancer differentiation. Downregulation of IRS1 and SOX9 may the possible key downstream genes involved in the process.
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Affiliation(s)
- Wenjing Ruan
- Department of Pathology, School of Medicine, Zhejiang University, 388 Yuhangtang Road, Hangzhou 310058, Zhejiang Province, China.
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17
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Huang YJ, Niu J, Liu Z, Wang LE, Sturgis EM, Wei Q. The functional IGFBP7 promoter -418G>A polymorphism and risk of head and neck cancer. Mutat Res 2010; 702:32-9. [PMID: 20599521 DOI: 10.1016/j.mrgentox.2010.06.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2010] [Revised: 06/12/2010] [Accepted: 06/23/2010] [Indexed: 11/18/2022]
Abstract
Insulin-like growth factor binding protein 7 (IGFBP7) functions mostly independent of the IGF signaling pathway and acts as a tumor suppressor in multiple cancers, but roles of IGFBP7 genetic variants in cancer remains unknown. In a hospital-based study of 1065 patients with squamous cell carcinoma of head and neck (SCCHN) and 1112 cancer-free controls of non-Hispanic whites, we investigated associations between two putatively functional IGFBP7 promoter single nucleotide polymorphisms (SNPs) (-702G>C, rs11573014 and -418G>A, rs4075349) and SCCHN risk. A significantly lower SCCHN risk was observed in those subjects carrying -418AG (adjusted OR=0.82, 95% CI=0.67-0.99) and -418AG+AA (adjusted OR=0.82, 95% CI=0.69-0.99) genotypes than those carrying the -418GG genotype, but not for the -702G>C SNP. However, those subjects carrying two common homozygous genotypes of these two SNPs (-418GG and -702GG) had an increased risk (adjusted OR=1.21, 95% CI=1.00-1.46) than did those carrying variant genotypes (-418AG+AA and -702CG+CC). This increased risk was more evident in subgroups of never smokers and subjects with oral cancer. Further functional analysis showed that the IGFBP7 -418A allele had significantly higher promoter and DNA-protein binding activities than did the G allele, suggesting a tumor suppressor role of this allelic change in the SCCHN etiology. We conclude that the functional variant -418G>C in the IGFBP7 promoter is associated with reduced risk of SCCHN, likely by enhancing the IGFBP7 promoter and DNA-protein binding activities. Larger studies are needed to validate our findings.
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Affiliation(s)
- Yu-Jing Huang
- Department of Epidemiology, The University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, USA
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18
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Amemiya Y, Yang W, Benatar T, Nofech-Mozes S, Yee A, Kahn H, Holloway C, Seth A. Insulin like growth factor binding protein-7 reduces growth of human breast cancer cells and xenografted tumors. Breast Cancer Res Treat 2010; 126:373-84. [DOI: 10.1007/s10549-010-0921-0] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2010] [Accepted: 04/23/2010] [Indexed: 11/29/2022]
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19
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Chen RY, Chen HX, Lin JX, She WB, Jiang P, Xu L, Tu YT. In-vivo transfection of pcDNA3.1-IGFBP7 inhibits melanoma growth in mice through apoptosis induction and VEGF downexpression. JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH : CR 2010; 29:13. [PMID: 20158915 PMCID: PMC2844372 DOI: 10.1186/1756-9966-29-13] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/16/2009] [Accepted: 02/16/2010] [Indexed: 02/05/2023]
Abstract
BACKGROUND Genome-wide RNA interference screening study revealed that loss of expression of insulin-like growth factor binding protein 7 (IGFBP7) is a critical step in development of a malignant melanoma (MM), and this secreted protein plays a central role in apoptosis of MM. In this study we constructed pcDNA3.1-IGFBP7 to obtain high expression of IGBPF7 and to inhibit the growth of MM in C57BL/6J mice. METHODS pcDNA3.1-IGFBP7 was transfected into B16-F10 cell, the expression of IGFBP7 was detected by RT-PCR and western blot. The proliferations and apoptosis rates of transfected and control cells were measured by CCK8 and FCM, respectively. The tumorigenicity and tumor growth in both pcDNA3.1-IGFBP7 group and control groups were studied in C57BL/6J mice model. IGFBP7, caspase-3, and VEGF expressions in tumor tissue were measured by immunohistochemistry. Apoptosis of tumors were detected by TUNEL. RESULTS We demonstrated this plasmid inhibited proliferation of B16-F10 melanoma cells efficiently in vivo, exploiting the high expression of IGFBP7. More importantly, in-vivo transfection of pcDNA3.1-IGFBP7 inhibited MM growth in C57BL/6J mice. The inhibition of MM growth was proved owing to apoptosis and reduced expression of VEGF induced by pcDNA3.1-IGFBP7. CONCLUSIONS These results suggest a potential new clinical strategy for MM gene treatment.
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Affiliation(s)
- Rong-Yi Chen
- Department of Dermatology, Affiliated Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022 PR China
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20
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Kreidl E, Oztürk D, Metzner T, Berger W, Grusch M. Activins and follistatins: Emerging roles in liver physiology and cancer. World J Hepatol 2009; 1:17-27. [PMID: 21160961 PMCID: PMC2999257 DOI: 10.4254/wjh.v1.i1.17] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/16/2009] [Revised: 09/10/2009] [Accepted: 09/17/2009] [Indexed: 02/06/2023] Open
Abstract
Activins are secreted proteins belonging to the TGF-β family of signaling molecules. Activin signals are crucial for differentiation and regulation of cell proliferation and apoptosis in multiple tissues. Signal transduction by activins relies mainly on the Smad pathway, although the importance of crosstalk with additional pathways is increasingly being recognized. Activin signals are kept in balance by antagonists at multiple levels of the signaling cascade. Among these, follistatin and FLRG, two members of the emerging family of follistatin-like proteins, can bind secreted activins with high affinity, thereby blocking their access to cell surface-anchored activin receptors. In the liver, activin A is a major negative regulator of hepatocyte proliferation and can induce apoptosis. The functions of other activins expressed by hepatocytes have yet to be more clearly defined. Deregulated expression of activins and follistatin has been implicated in hepatic diseases including inflammation, fibrosis, liver failure and primary cancer. In particular, increased follistatin levels have been found in the circulation and in the tumor tissue of patients suffering from hepatocellular carcinoma as well as in animal models of liver cancer. It has been argued that up-regulation of follistatin protects neoplastic hepatocytes from activin-mediated growth inhibition and apoptosis. The use of follistatin as biomarker for liver tumor development is impeded, however, due to the presence of elevated follistatin levels already during preceding stages of liver disease. The current article summarizes our evolving understanding of the multi-faceted activities of activins and follistatins in liver physiology and cancer.
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Affiliation(s)
- Emanuel Kreidl
- Emanuel Kreidl, Deniz Öztürk, Thomas Metzner, Walter Berger, Michael Grusch, Institute of Cancer Research, Department of Medicine I, Medical University of Vienna, Borschkegasse 8a, Vienna A-1090, Austria
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21
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Costello JF, Hong C, Plass C, Smiraglia DJ. Restriction landmark genomic scanning: analysis of CpG islands in genomes by 2D gel electrophoresis. Methods Mol Biol 2009; 507:131-48. [PMID: 18987812 DOI: 10.1007/978-1-59745-522-0_11] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Restriction landmark genomic scanning (RLGS) is a method that provides a quantitative genetic and epigenetic (cytosine methylation) assessment of thousands of CpG islands in a single gel without prior knowledge of gene sequence. The method is based on two-dimensional separation of radiolabeled genomic DNA into nearly 2,000 discrete fragments that have a high probability of containing gene sequences. Genomic DNA is digested with an infrequently cutting restriction enzyme, such as NotI or AscI, radiolabeled at the cleaved ends, digested with a second restriction enzyme, and then electrophoresed through a narrow, 60-cm-long agarose tube-shaped gel. The DNA in the tube gel is then digested by a third, more frequently cutting restriction enzyme and electrophoresed, in a direction perpendicular to the first separation, through a 5% nondenaturing polyacrylamide gel, and the gel is autoradiographed. Radiolabeled NotI or AscI sites are frequently used as "landmarks" because NotI or AscI cannot cleave methylated sites and since an estimated 89% and 83% of the recognition sites, respectively, are found within CpG islands. Using a methylation-sensitive enzyme, the technique has been termed RLGS-M. The resulting RLGS profile displays both the copy number and methylation status of the CpG islands. Integrated with high-resolution gene copy-number analyses, RLGS enables one to define genetic or epigenetic alteration in cells. These profiles are highly reproducible and are therefore amenable to inter- and intraindividual DNA sample comparisons. RLGS was the first of many technologies to allow large-scale DNA methylation analysis of CpG islands.
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Affiliation(s)
- Joseph F Costello
- Department of Neurological Surgery, University of California San Francisco Comprehensive Cancer Center, San Francisco, CA, USA
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22
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Kutsukake M, Ishihara R, Momose K, Isaka K, Itokazu O, Higuma C, Matsutani T, Matsuda A, Sasajima K, Hara T, Tamura K. Circulating IGF-binding protein 7 (IGFBP7) levels are elevated in patients with endometriosis or undergoing diabetic hemodialysis. Reprod Biol Endocrinol 2008; 6:54. [PMID: 19019211 PMCID: PMC2600820 DOI: 10.1186/1477-7827-6-54] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/08/2008] [Accepted: 11/19/2008] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND Insulin-like growth factor-binding protein-7 (IGFBP7) is a secretory protein with a molecular mass of approximately 30 kDa. It is abundantly expressed in the uterine endometrium during the secretory phase of the menstrual cycle. Decreased IGFBP7 expression has been observed in some cancers and leiomyomata. METHODS To determine whether serum IGFBP7 levels reflect changes in uterine IGFBP7 expression in humans during the menstrual cycle, and to examine whether serum IGFBP7 levels are altered in patients with various disorders, we developed a novel, dual-antibody sandwich enzyme-linked immunosorbent assay (ELISA). Firstly, concentrations of IGFBP7 released into the medium were determined in cultured endometrial stromal and glandular cells. Blood samples were collected from women who had normal menstrual cycles and who had been diagnosed with endometriosis. Serum from hemodialysis patients and gastrointestinal cancers was also used to determine the IGFBP7 levels. RESULTS Using this new ELISA, we demonstrated that cultured uterine cells secrete IGFBP7 into the medium. Patients with endometriosis and those with type II diabetes mellitus undergoing hemodialysis had significantly higher serum concentrations of IGFBP7 than the relevant control subjects. There were no differences in serum IGFBP7 levels in women at different stages of the menstrual cycle. Furthermore, serum IGFBP7 levels in patients with colorectal, esophageal, or endometrial cancer were not different than normal healthy subjects. CONCLUSION Our observations suggest that IGFBP7 is associated with the pathophysiology of endometriosis and diabetes mellitus, and that serum IGFBP7 levels do not reflect enhanced uterine expression of IGFBP7 mRNA during the menstrual cycle.
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Affiliation(s)
- Masahiko Kutsukake
- Department of Endocrine Pharmacology, Tokyo University of Pharmacy and Life Sciences, 1432-1, Horinouchi, Hachioji, Tokyo 193-0392, Japan
| | - Ryosuke Ishihara
- Department of Endocrine Pharmacology, Tokyo University of Pharmacy and Life Sciences, 1432-1, Horinouchi, Hachioji, Tokyo 193-0392, Japan
| | - Katsutoshi Momose
- Department of Endocrine Pharmacology, Tokyo University of Pharmacy and Life Sciences, 1432-1, Horinouchi, Hachioji, Tokyo 193-0392, Japan
| | - Keiichi Isaka
- Department of Obstetrics and Gynecology, Tokyo Medical University, 6-7-1 Nishishinjuku, Shinjuku-ku, Tokyo 160-0023, Japan
| | - Osamu Itokazu
- Department of Obstetrics and Gynecology, Tokyo Medical University, 6-7-1 Nishishinjuku, Shinjuku-ku, Tokyo 160-0023, Japan
| | - Chinatsu Higuma
- Department of Obstetrics and Gynecology, Tokyo Medical University, 6-7-1 Nishishinjuku, Shinjuku-ku, Tokyo 160-0023, Japan
| | - Takeshi Matsutani
- Surgery for Organ Function and Biological Regulation, Graduate School of Medicine, Nippon Medical School, 1-7-1 Nagayama, Tama, Tokyo 206-8512, Japan
| | - Akihisa Matsuda
- Surgery for Organ Function and Biological Regulation, Graduate School of Medicine, Nippon Medical School, 1-7-1 Nagayama, Tama, Tokyo 206-8512, Japan
| | - Koji Sasajima
- Surgery for Organ Function and Biological Regulation, Graduate School of Medicine, Nippon Medical School, 1-7-1 Nagayama, Tama, Tokyo 206-8512, Japan
| | - Takahiko Hara
- Stem Cell Project Group, the Tokyo Metropolitan Institute of Medical Science, 3-18-22 Honkomagome, Bunkyo-ku, Tokyo 113-8613, Japan
| | - Kazuhiro Tamura
- Department of Endocrine Pharmacology, Tokyo University of Pharmacy and Life Sciences, 1432-1, Horinouchi, Hachioji, Tokyo 193-0392, Japan
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Pen A, Moreno MJ, Durocher Y, Deb-Rinker P, Stanimirovic DB. Glioblastoma-secreted factors induce IGFBP7 and angiogenesis by modulating Smad-2-dependent TGF-beta signaling. Oncogene 2008; 27:6834-44. [PMID: 18711401 DOI: 10.1038/onc.2008.287] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Insulin-like growth factor-binding protein 7 (IGFBP7) is a selective biomarker of glioblastoma (GBM) vessels, strongly expressed in tumor endothelial cells and vascular basement membrane. IGFBP7 gene regulation and its potential role in tumor angiogenesis remain unclear. Mechanisms of IGFBP7 induction and its angiogenic capacity were examined in human brain endothelial cells (HBECs) exposed to tumor-like conditions. HBEC treated with GBM cell (U87MG)-conditioned media (-CM) exhibited fourfold upregulation of IGFBP7 mRNA and protein compared to control cells. IGFBP7 gene regulation in HBEC was methylation independent. U87MG-CM analysed by enzyme-linked immunosorbent assay contained approximately 5 pM transforming growth factor (TGF)-beta1, a concentration sufficient to stimulate IGFBP7 in HBEC to similar levels as U87MG-CM. Both pan-TGF-beta-neutralizing antibody (1D11) and the TGF-beta1 receptor (activin receptor-like kinase 5, ALK5) antagonist, SB431542, blocked U87MG-CM-induced IGFBP7 expression in HBEC, indicating that TGF-beta1 is an important tumor-secreted effector capable of IGFBP7 induction in endothelial cells. HBEC exposed to either U87MG-CM or IGFBP7 protein exhibited increased capillary-like tube (CLT) formation in Matrigel. Both TGF-beta1- and U87MG-CM-induced Smad-2 phosphorylation and U87MG-CM-induced CLT formation in HBEC were inhibited by the ALK5 antagonist, SB431542. These data suggest that proangiogenic IGFBP7 may be induced in brain endothelial cells by TGF-betas secreted by GBM, most likely through TGF-beta1/ALK5/Smad-2 pathway.
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Affiliation(s)
- A Pen
- Cerebrovascular Research Group, Neurobiology Program, Institute for Biological Sciences, National Research Council of Canada, Ottawa, Ontario, Canada
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Restriction landmark genomic scanning (RLGS) spot identification by second generation virtual RLGS in multiple genomes with multiple enzyme combinations. BMC Genomics 2007; 8:446. [PMID: 18053125 PMCID: PMC2235865 DOI: 10.1186/1471-2164-8-446] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2007] [Accepted: 11/30/2007] [Indexed: 11/18/2022] Open
Abstract
Background Restriction landmark genomic scanning (RLGS) is one of the most successfully applied methods for the identification of aberrant CpG island hypermethylation in cancer, as well as the identification of tissue specific methylation of CpG islands. However, a limitation to the utility of this method has been the ability to assign specific genomic sequences to RLGS spots, a process commonly referred to as "RLGS spot cloning." Results We report the development of a virtual RLGS method (vRLGS) that allows for RLGS spot identification in any sequenced genome and with any enzyme combination. We report significant improvements in predicting DNA fragment migration patterns by incorporating sequence information into the migration models, and demonstrate a median Euclidian distance between actual and predicted spot migration of 0.18 centimeters for the most complex human RLGS pattern. We report the confirmed identification of 795 human and 530 mouse RLGS spots for the most commonly used enzyme combinations. We also developed a method to filter the virtual spots to reduce the number of extra spots seen on a virtual profile for both the mouse and human genomes. We demonstrate use of this filter to simplify spot cloning and to assist in the identification of spots exhibiting tissue-specific methylation. Conclusion The new vRLGS system reported here is highly robust for the identification of novel RLGS spots. The migration models developed are not specific to the genome being studied or the enzyme combination being used, making this tool broadly applicable. The identification of hundreds of mouse and human RLGS spot loci confirms the strong bias of RLGS studies to focus on CpG islands and provides a valuable resource to rapidly study their methylation.
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25
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Smith P, Nicholson LJ, Syed N, Payne A, Hiller L, Garrone O, Occelli M, Gasco M, Crook T. Epigenetic inactivation implies independent functions for insulin-like growth factor binding protein (IGFBP)-related protein 1 and the related IGFBPL1 in inhibiting breast cancer phenotypes. Clin Cancer Res 2007; 13:4061-8. [PMID: 17634530 DOI: 10.1158/1078-0432.ccr-06-3052] [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: 11/16/2022]
Abstract
PURPOSE To analyze epigenetic regulation of two related genes, insulin-like growth factor binding protein-related protein 1 (IGFBP-rP1) and IGFBPL1, and its significance as a determinant of clinical phenotypes in human breast cancer. EXPERIMENTAL DESIGN We have investigated the expression and epigenetic regulation of IGFBP-rP1 and IGFBPL1 in human breast cancer cell lines and primary and metastatic carcinomas. RESULTS Expression of IGFBP-rP1 and IGFBPL1 is down-regulated in breast cancer cell lines. Aberrant methylation in the CpG islands of each gene correlates well with loss of expression at the mRNA level. Analysis of methylation in DNA isolated from human primary breast tumors showed that methylation in either gene was associated with a worse overall survival (OS; P=0.008) and disease-free survival (DFS) following surgery (P=0.04) and worse DFS following adjuvant chemotherapy (P=0.01). Methylation of IGFBP-rP1 alone was associated with a trend toward decreased OS (P=0.10) and decreased DFS (P=0.25). Methylation in IGFBPL1 was clearly associated with worse OS (P=0.001) and DFS (P<0.0001). Methylation in either IGFBP-rP1 or IGFBPL1 was significantly associated with nodal disease (P<0.001). CONCLUSIONS Expression of IGFBP-rP1 and IGFBPL1 is regulated by aberrant hypermethylation in breast cancer, implying that inactivation of these genes is involved in the pathogenesis of this malignancy. Analysis of methylation of these genes may have utility in prediction of clinical phenotypes, such as nodal disease and response to chemotherapy.
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Affiliation(s)
- Paul Smith
- The Breakthrough Toby Robins Breast Cancer Research Centre at The Institute of Cancer Research, Mary-Jean Mitchell Green Building, Chester Beatty Laboratories, London, UK
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26
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Peterson LF, Wang Y, Lo MC, Yan M, Kanbe E, Zhang DE. The multi-functional cellular adhesion molecule CD44 is regulated by the 8;21 chromosomal translocation. Leukemia 2007; 21:2010-9. [PMID: 17657222 DOI: 10.1038/sj.leu.2404849] [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: 01/07/2023]
Abstract
The 8;21 translocation is a common chromosomal abnormality in acute myeloid leukemia (AML). We recently identified a naturally occurring leukemogenic splice variant, AML1-ETO9a (acute myeloid leukemia-1 transcription factor and the eight-twenty-one corepressor-9a), of t(8;21). To understand the leukemic potential of AML1-ETO9a, we performed microarray analysis with the murine multipotential hematopoietic FDCP-mix A4 cell line. We identified changes in expression of various genes including CD44. CD44 is a type I transmembrane protein and functions as the major cellular adhesion molecule for hyaluronic acid, a component of the extracellular matrix. CD44 is expressed in most human cell types and is implicated in myeloid leukemia pathogenesis. We show that the presence of AML1-ETO9a significantly increased the expression of CD44 at both RNA and protein levels. Furthermore, the CD44 promoter is bound by AML1-ETO9a and AML1-ETO at the chromatin level. In addition, in the AML1-ETO9a leukemia mouse model CD44 is regulated in a cell context-dependent manner. Thus, our observations suggest that AML1-ETO and its splice variant AML1-ETO9a are able to regulate the expression of the CD44 gene, linking the 8;21 translocation to the regulation of a cell adhesion molecule that is involved in the growth and maintenance of the AML blast/stem cells.
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Affiliation(s)
- L F Peterson
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, CA, USA
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27
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Subramanian A, Sharma A, Mokbel K. Insulin-like growth factor binding proteins and breast cancer. Breast Cancer Res Treat 2007; 107:181-94. [PMID: 17611793 DOI: 10.1007/s10549-007-9549-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2007] [Accepted: 02/12/2007] [Indexed: 11/30/2022]
Affiliation(s)
- Ashok Subramanian
- Department of Breast Surgery, St Georges Hospital NHS Trust, Blackshaw Road, Tooting, London, UK.
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28
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Sato Y, Chen Z, Miyazaki K. Strong suppression of tumor growth by insulin-like growth factor-binding protein-related protein 1/tumor-derived cell adhesion factor/mac25. Cancer Sci 2007; 98:1055-63. [PMID: 17465992 PMCID: PMC11158653 DOI: 10.1111/j.1349-7006.2007.00502.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Insulin-like growth factor binding protein-related protein 1 (IGFBP-rP1) has been shown to induce cellular senescence or apoptosis of breast and prostate cancer cell lines in vitro. To examine whether IGFBP-rP1 acts as a tumor-suppressive protein in vivo, we established two model systems. Expression of IGFBP-rP1 in the human bladder carcinoma cell line EJ-1 was blocked by RNA interference. Human colon cancer cell line DLD-1, which did not express endogenous IGFBP-rP1, was transfected with an IGFBP-rP1 expression vector. When injected intraperitoneally or subcutaneously into nude mice, the IGFBP-rP1-expressing EJ-1 and DLD-1 cell lines grew poorly, whereas the IGFBP-rP1 non-producers grew rapidly and produced large tumors. In monolayer culture the IGFBP-rP1 producers and non-producers grew similarly in each model, whereas in soft agar culture the former produced far less colonies than the latter. The IGFBP-rP1 producers had IGFBP-rP1 bound to the cell surface, and adhered more efficiently to fibronectin and laminin-5 than the respective non-producers. Expression of IGFBP-rP1 did not affect the efficiency of insulin signaling. These results demonstrate that IGFBP-rP1 strongly suppresses tumor growth by an insulin-independent or insulin-like growth factor-independent mechanism. Cell surface IGFBP-rP1 may reduce the anchorage-independent growth ability, leading to the marked loss of tumorigenicity.
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Affiliation(s)
- Yuichiro Sato
- Division of Cell Biology, Kihara Institute for Biological Research, Yokohama City University, 641-12 Maioka-cho, Totsuka-ku, Yokohama 244-0813, Japan
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29
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Chen Y, Pacyna-Gengelbach M, Ye F, Knösel T, Lund P, Deutschmann N, Schlüns K, Kotb WFMA, Sers C, Yasumoto H, Usui T, Petersen I. Insulin-like growth factor binding protein-related protein 1 (IGFBP-rP1) has potential tumour-suppressive activity in human lung cancer. J Pathol 2007; 211:431-8. [PMID: 17236181 DOI: 10.1002/path.2132] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The expression of insulin-like growth factor binding protein-related protein 1 (IGFBP-rP1) is decreased in various tumours, but the role of IGFBP-rP1 in lung cancer is not yet clear. In this study, IGFBP-rP1 expression in lung cancer cell lines was evaluated and reduced expression of IGFBP-rP1 was found. In tissue microarrays containing 138 primary tumours and 20 normal lung tissues analysed by immunohistochemistry, 58 tumours (42%) exhibited no expression of IGFBP-rP1, while all 20 normal lung tissues showed high expression. In squamous cell lung cancer, low expression of IGFBP-rP1 was significantly linked to high-grade tumours. Treatment with 5-aza-2'-deoxycytidine restored the expression of IGFBP-rP1 in three of four lung cancer cell lines. Sequencing of PCR products of sodium bisulphite-treated genomic DNA from the three lung cancer cell lines revealed a heterogeneous methylation pattern in the region of exon 1 and intron 1. Stable transfection of IGFBP-rP1 full-length cDNA into the H2170 lung cancer cell line led to increased expression of IGFBP-rP1 protein. IGFBP-rP1-positive transfectants exhibited remarkably reduced colony-forming ability in soft agar, suppression of tumour growth rate in nude mice, and increased apoptotic cell number as well as activated caspase-3 expression level. The data suggest that IGFBP-rP1 is a tumour suppressor inactivated by DNA methylation in human lung cancer.
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Affiliation(s)
- Y Chen
- Institute of Pathology, University Hospital Charité, Schumannstr 20-21, D-10098 Berlin, Germany
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30
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Ruan WJ, Lin J, Xu EP, Xu FY, Ma Y, Deng H, Huang Q, Lv BJ, Hu H, Cui J, Di MJ, Dong JK, Lai MD. IGFBP7 plays a potential tumor suppressor role against colorectal carcinogenesis with its expression associated with DNA hypomethylation of exon 1. J Zhejiang Univ Sci B 2007; 7:929-32. [PMID: 17048309 PMCID: PMC1635813 DOI: 10.1631/jzus.2006.b0929] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Insulin-like growth factor binding-protein-7 (IGFBP7) was obtained from our previous colonic adenocarcinoma (CRC) and normal mucosa suppression subtraction hybridization (SSH) cDNA libraries. By RT-PCR and immunohistochemistry, we found that IGFBP7 was overexpressed in CRC tissue compared to normal tissue. However, our in vitro experiments performed in 10 CRC cell lines showed that IGFBP7 expressed only in SW480 and Caco2 cell lines, which implied an underlying reversible regulatory mechanism. Using methylation-specific PCR (MSP) and bisulfite sodium PCR (BSP), we found that its expression was associated with DNA hypomethylation of exon1. This was further supported by the in vitro study which showed restored IGFBP7 expression after demethylation agent 5-aza-2'-deoxycytidine treatment. Correlation analysis between IGFBP7 expression and prognosis indicated that overexpression of IGFBP7 in CRC tissue correlated with favourable survival. Investigation of the functional role of IGFBP7 through transfection studies showed that IGFBP7 protein could inhibit growth rate, decrease colony formation activity, and induce apoptosis in RKO and SW620 cells, suggesting it a potential tumor suppressor protein in colorectal carcinogenesis. In conclusion, our study clearly demonstrated that IGFBP7 plays a potential tumor suppressor role against colorectal carcinogenesis and its expression is associated with DNA hypomethylation of exon 1.
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Affiliation(s)
- Wen-jing Ruan
- Department of Pathology, School of Medicine, Zhejiang University, Hangzhou 310031, China
| | - Jie Lin
- Department of Pathology, School of Medicine, Zhejiang University, Hangzhou 310031, China
| | - En-ping Xu
- Department of Pathology, School of Medicine, Zhejiang University, Hangzhou 310031, China
| | - Fang-ying Xu
- Department of Pathology, School of Medicine, Zhejiang University, Hangzhou 310031, China
- Department of Basic Medicine, Hangzhou Teachers College, Hangzhou 310036, China
| | - Yu Ma
- Department of Pathology, School of Medicine, Zhejiang University, Hangzhou 310031, China
| | - Hong Deng
- Department of Pathology, School of Medicine, Zhejiang University, Hangzhou 310031, China
| | - Qiong Huang
- Department of Pathology, School of Medicine, Zhejiang University, Hangzhou 310031, China
| | - Bing-jian Lv
- Department of Pathology, School of Medicine, Zhejiang University, Hangzhou 310031, China
| | - Hu Hu
- Department of Pathology, School of Medicine, Zhejiang University, Hangzhou 310031, China
| | - Jing Cui
- Department of Pathology, School of Medicine, Zhejiang University, Hangzhou 310031, China
| | - Mei-juan Di
- Department of Pathology, the People’s No. 1 Hospital of Xiaoshan, Hangzhou 311201, China
| | - Jian-kang Dong
- Center for Disease Control and Prevention of Xiaoshan, Hangzhou 311201, China
| | - Mao-de Lai
- Department of Pathology, School of Medicine, Zhejiang University, Hangzhou 310031, China
- †E-mail:
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Ye F, Chen Y, Knösel T, Schlüns K, Pacyna-Gengelbach M, Deutschmann N, Lai M, Petersen I. Decreased expression of insulin-like growth factor binding protein 7 in human colorectal carcinoma is related to DNA methylation. J Cancer Res Clin Oncol 2006; 133:305-14. [PMID: 17136345 DOI: 10.1007/s00432-006-0171-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2006] [Accepted: 10/27/2006] [Indexed: 11/29/2022]
Abstract
PURPOSE Insulin-like growth factor binding protein 7 (IGFBP-7) is considered a tumor suppressor in various cancers, but its role in colorectal cancer (CRC) is still uncertain. The aims of this study were to analyze the IGFBP-7 expression, and explore the mechanism responsible for the inactivation of IGFBP-7 in CRC. METHODS mRNA expression was studied by RT-PCR and Northern blot analysis of cultured cells. Methylation status was analyzed by treatment with 5-aza-2'-deoxycytidine followed by sequencing of PCR products of sodium bisulfite-treated genomic DNA. IGFBP-7 protein expression was evaluated by immunohistochemistry (IHC) on tissue microarrays. RESULTS mRNA expression was lost in six out of eight CRC cell lines as compared to normal colon cells. DNA methylation was found in the region of exon 1 and intron 1 of IGFBP-7. In tumor tissue, 107 out of 279 samples showed a negative expression of IGFBP-7 by IHC, which was significantly associated with poor prognosis. The analysis of 37 paired cancerous and normal mucosa samples confirmed the downregulation in the tumors, but revealed variable basal expression levels of IGFBP-7 in normal mucosal samples. CONCLUSIONS DNA methylation is a mechanism responsible for IGFBP-7 gene silencing providing a target for therapeutic intervention of this tumor suppressor gene.
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Affiliation(s)
- Fei Ye
- Institute of Pathology, Charité University Medicine Berlin-Campus Mitte, 10098 Berlin, Germany
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32
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Rodgarkia-Dara C, Vejda S, Erlach N, Losert A, Bursch W, Berger W, Schulte-Hermann R, Grusch M. The activin axis in liver biology and disease. Mutat Res 2006; 613:123-37. [PMID: 16997617 DOI: 10.1016/j.mrrev.2006.07.002] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2006] [Revised: 07/27/2006] [Accepted: 07/27/2006] [Indexed: 12/22/2022]
Abstract
Activins are a closely related subgroup within the TGFbeta superfamily of growth and differentiation factors. They consist of two disulfide-linked beta subunits. Four mammalian activin beta subunits termed beta(A), beta(B), beta(C), and beta(E), respectively, have been identified. Activin A, the homodimer of two beta(A) subunits, has important regulatory functions in reproductive biology, embryonic development, inflammation, and tissue repair. Several intra- and extracellular antagonists, including the activin-binding proteins follistatin and follistatin-related protein, serve to fine-tune activin A activity. In the liver there is compelling evidence that activin A is involved in the regulation of cell number by inhibition of hepatocyte replication and induction of apoptosis. In addition, activin A stimulates extracellular matrix production in hepatic stellate cells and tubulogenesis of sinusoidal endothelial cells, and thus contributes to restoration of tissue architecture during liver regeneration. Accumulating evidence from animal models and from patient data suggests that deregulation of activin A signaling contributes to pathologic conditions such as hepatic inflammation and fibrosis, acute liver failure, and development of liver cancer. Increased production of activin A was suggested to be a contributing factor to impaired hepatocyte regeneration in acute liver failure and to overproduction of extracellular matrix in liver fibrosis. Recent evidence suggests that escape of (pre)neoplastic hepatocytes from growth control by activin A through overexpression of follistatin and reduced activin production contributes to hepatocarcinogenesis. The role of the activin subunits beta(C) and beta(E), which are both highly expressed in hepatocytes, is still quite incompletely understood. Down-regulation in liver tumors and a growth inhibitory function similar to that of beta(A) has been shown for beta(E). Contradictory results with regard to cell proliferation have been reported for beta(C). The profound involvement of the activin axis in liver biology and in the pathogenesis of severe hepatic diseases suggests activin as potential target for therapeutic interventions.
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Affiliation(s)
- Chantal Rodgarkia-Dara
- Department of Medicine I, Division: Institute of Cancer Research, Medical University of Vienna, Borschkegasse 8a, A-1090 Vienna, Austria
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Fridman AL, Tang L, Kulaeva OI, Ye B, Li Q, Nahhas F, Roberts PC, Land SJ, Abrams J, Tainsky MA. Expression Profiling Identifies Three Pathways Altered in Cellular Immortalization: Interferon, Cell Cycle, and Cytoskeleton. ACTA ACUST UNITED AC 2006; 61:879-89. [PMID: 16960018 DOI: 10.1093/gerona/61.9.879] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Abrogation of cellular senescence, resulting in immortalization, is a necessary step in the tumorigenic transformation of a cell. Four independent, spontaneously immortalized Li-Fraumeni syndrome (LFS) cell lines were used to analyze the gene expression changes that may have given these cell lines the growth advantage required to become immortal. A cellular senescence-like phenotype can be induced in immortal LFS cells by treating them with the DNA methyltransferase (DNMT) inhibitor 5-aza-deoxycytidine. We hypothesized, therefore, that genes epigenetically silenced by promoter methylation are potentially key regulators of senescence. We used microarrays to compare the epigenetic gene expression profiles of precrisis LFS cells with immortal LFS cells. Gene ontology analysis of the expression data revealed a statistically significant contribution of interferon pathway, cell cycle, and cytoskeletal genes in the process of immortalization. The identification of the genes and pathways regulating immortalization will lead to a better understanding of cellular immortalization and molecular targets in cancer and aging.
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Affiliation(s)
- Aviva Levine Fridman
- Program in Molecular Biology and Human Genetics, Barbara Ann Karmanos Cancer Institute, and Center for Molecular Medicine and Genetics, Wayne State University School of Medicine, 110 East Warren Ave., Detroit, Michigan 48201, USA
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Meinbach DS, Lokeshwar BL. Insulin-like growth factors and their binding proteins in prostate cancer: Cause or consequence?☆. Urol Oncol 2006; 24:294-306. [PMID: 16818181 DOI: 10.1016/j.urolonc.2005.12.004] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2005] [Revised: 12/27/2005] [Accepted: 12/28/2005] [Indexed: 12/29/2022]
Abstract
Insulin-like growth factors (IGFs) promote growth and survival of many types of tumor cells. Epidemiologic studies have implicated carcinogenesis with high levels of IGFs in circulation or in tissues. The levels of IGF binding proteins (IGFBPs) have been associated with reduced risk for prostate and other cancers. Experimental studies have implicated high levels of IGF-I directly and IGFBP-3 inversely in prostate cancer growth, survival, and progression. However, recent evidence suggests a much weaker association of IGF-I with prostate cancer development and a stronger antagonistic association of IGFBP-3 with prostate cancer progression. Considering the clonal heterogeneity and unpredictable progression pattern of prostate cancer, the role of any single growth factor or its regulator (IGFBP) as a single determining factor is limited. This review is a critical appraisal of the role of IGFs, IGFBP, and IGF-I receptor (the IGF axis) in both experimental and clinical prostate cancer genesis and progression.
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Affiliation(s)
- David S Meinbach
- Department of Urology, Leonard Miller School of Medicine, University of Miami, Miami, FL 33101, USA
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35
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Zhou D, Qiao W, Wan Y, Lu Z. Microarray-based methylation analysis using dual-color fluorescence hybridization. ACTA ACUST UNITED AC 2006; 66:33-43. [PMID: 16442635 DOI: 10.1016/j.jbbm.2005.11.004] [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: 08/05/2005] [Revised: 11/24/2005] [Accepted: 11/28/2005] [Indexed: 10/25/2022]
Abstract
BACKGROUND Aberrant DNA methylation of CpG sites is among the earliest and most frequent alterations in cancer. It is of great importance to develop simple, high-throughput and quantitative methods for methylation detection. METHODS A high-throughput methylation analysis method has been developed based on microarray and dual-color fluorescence hybridization. The genomic DNA was treated with bisulfite, resulting in conversion of non-methylated cytosine, but not methylated cytosine, into uracil within CpG islands of interest. PCR products of the treated genomic templates were spotted and immobilized onto a poly-l-lysine coated glass slide to fabricate a microarray and then interrogated by hybridization with dual-color probes to determine the methylation status. The hybridized signals were obtained with a scanner and the results were analyzed with the software Genepix Pro 3.0. RESULTS The methylation status of the CpG islands of IGFBP7 gene has been successfully evaluated by the microarray method for twenty-seven samples. All the investigated samples, including twenty human breast tumor tissues, six corresponding normal human breast tissues and one liver cell line, all CpG sites were found completely methylated. CONCLUSIONS The microarray technology has been proven to have potential for high-throughput detection of the methylation status for a given gene in multi-genomic samples, which could be a novel approach for rapidly screening DNA methylation marker for early stage cancer diagnosis.
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Affiliation(s)
- Dongrui Zhou
- State Key Laboratory of Bioelectronics, Southeast University, Nanjing, 210096, China
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Zhou D, Qiao W, Yang L, Lu Z. Bisulfite-modified target DNA array for aberrant methylation analysis. Anal Biochem 2006; 351:26-35. [PMID: 16516134 DOI: 10.1016/j.ab.2006.01.006] [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: 09/14/2005] [Revised: 12/06/2005] [Accepted: 01/04/2006] [Indexed: 11/17/2022]
Abstract
Aberrant DNA methylation of CpG islands is among the earliest and most frequent alterations in cancer. It is of great importance to develop simple and high-throughput methods of methylation analysis for earlier cancer diagnosis or the detection of recurrence. In this study, bisulfite-modified target DNA arrays were prepared on positively charged nylon membrane with two different procedures: fixing PCR products and fixing genomic DNA. First, a bisulfite PCR product array was prepared through fixing PCR products amplified in bisulfite sequencing primers from the bisulfite-modified genomic DNA of different clinical samples on membrane. Furthermore, bisulfite-modified genomic DNA of the different samples was directly fixed on membrane to fabricate bisulfite genomic DNA arrays. The two kinds of arrays were hybridized by probes labeled with digoxigenin, and the hybridization signals were obtained through chemiluminescent detection. The methylation statuses of the IGFBP7 gene for breast tumor and normal tissue samples and for normal human blood cell samples were detected successfully by the two procedures. It was shown that the methods are reliable and sensitive and that they have high potential in screening molecular methylation markers from a large number of clinical samples.
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Affiliation(s)
- Dongrui Zhou
- State Key Laboratory of Bioelectronics, Southeast University, Nanjing 210096, China
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Yamashita S, Tsujino Y, Moriguchi K, Tatematsu M, Ushijima T. Chemical genomic screening for methylation-silenced genes in gastric cancer cell lines using 5-aza-2'-deoxycytidine treatment and oligonucleotide microarray. Cancer Sci 2006; 97:64-71. [PMID: 16367923 PMCID: PMC11159443 DOI: 10.1111/j.1349-7006.2006.00136.x] [Citation(s) in RCA: 201] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
To identify novel methylation-silenced genes in gastric cancers, we carried out a chemical genomic screening, a genome-wide search for genes upregulated by treatment with a demethylating agent, 5-aza-2'-deoxycytidine (5-aza-dC). After 5-aza-dC treatment of a gastric cancer cell line (AGS) 579 genes were upregulated 16-fold or more, using an oligonucleotide microarray with 39,000 genes. From these genes, we selected 44 known genes on autosomes whose silencing in gastric cancer has not been reported. Thirty-two of these had CpG islands (CGI) in their putative promoter regions, and all of the CGI were methylated in AGS, giving an estimated number of 421+/-75 (95% confidence interval) methylation-silenced genes. Additionally, we analyzed the methylation status of 16 potential tumor-related genes with promoter CGI that were upregulated four-fold or more, and 14 of these were methylated in AGS. Methylation status of the 32 randomly selected and 16 potential tumor-related genes was analyzed in 10 primary gastric cancers, and 42 genes (ABHD9, ADFP, ALDH1A3, ANXA5, AREG, BDNF, BMP7, CAV1, CDH2, CLDN3, CTSL, EEF1A2, F2R, FADS1, FSD1, FST, FYN, GPR54, GREM1, IGFBP3, IGFBP7, IRS2, KISS1, MARK1, MLF1, MSX1, MTSS1, NT5E, PAX6, PLAGL1, PLAU, PPIC, RBP4, RORA, SCRN1, TBX3, TFAP2C, TNFSF9, ULBP2, WIF1, ZNF177 and ZNF559) were methylated in at least one primary gastric cancer. A metastasis suppressor gene, MTSS1, was located in a genomic region with frequent loss of heterozygosity (8q22), and was expressed abundantly in the normal gastric mucosa, suggesting its role in gastric carcinogenesis. (Cancer Sci 2006; 97: 64 -71).
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Affiliation(s)
- Satoshi Yamashita
- Carcinogenesis Division, National Cancer Center Research Institute, 1-1 Tsukiji 5-chome, Chuo-ku, Tokyo 104-0045, Japan
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Suzuki Y. Expression of IGFBPs in the developing mouse submandibular and von Ebner's glands. ACTA ACUST UNITED AC 2005; 211:189-96. [PMID: 16369822 DOI: 10.1007/s00429-005-0071-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/29/2005] [Indexed: 11/28/2022]
Abstract
The expression of insulin-like growth factor binding proteins (IGFBPs) in the developing mouse submandibular and von Ebner's glands was determined by in situ hybridization and by an immunohistochemical method. In the submandibular glands, IGFBP-2 and IGFBP-4 mRNAs were expressed in the terminal end-buds (TEB) at E13-E17, concomitant with epithelial branching. IGFBP-3 mRNA was expressed in the mesenchyme surrounding the TEB; and IGFBP-5 mRNA, in the ducts. At E17, IGFBP-5 mRNA expression was observed not only in the ducts but also in the TEB. Similarly, IGFBP-4 mRNA expression was observed not only in the TEB but also in the mesenchyme. After birth, IGFBP-4 expression was observed only in the connective tissue and disappeared by P14. That of IGFBP-7 appeared at P1 and was observed in the connective tissue until P21. The IGFBP-5 mRNA expression pattern after birth was the same as that seen at E17, but at P21 IGFBP-5 was immunohistochemically expressed only in the duct. The mRNA level of IGFBP-2 expression at postnatal days was weak, but its protein was detected in the ducts and acini at P14-P21. In von Ebner's glands, which appeared at the base of the circumvallate papillae at E17, only IGFBP-2 and IGFBP-4 mRNAs were expressed in the ducts and acini. Postnatally, IGFBP-4 was substituted by IGFBP-5 in the same region. Immunohistochemically, IGFBP-5 and IGFBP-2 were expressed in the ducts and acini at P14-P21. Throughout the study, IGFBP-6 was not detected by in situ hybridization, the immunoreactivity for it was observed in the nerve fibers of submandibular and von Ebner's glands. These data support a role for these molecules as local mediators of salivary growth and differentiation.
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Affiliation(s)
- Yuko Suzuki
- Department of Oral Anatomy, School of Dentistry, Health Sciences University of Hokkaido, 061-0293 Ishikari-Tobetsu, Japan.
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Burger AM, Leyland-Jones B, Banerjee K, Spyropoulos DD, Seth AK. Essential roles of IGFBP-3 and IGFBP-rP1 in breast cancer. Eur J Cancer 2005; 41:1515-27. [PMID: 15979304 DOI: 10.1016/j.ejca.2005.04.023] [Citation(s) in RCA: 109] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2005] [Revised: 04/11/2005] [Accepted: 04/18/2005] [Indexed: 11/29/2022]
Abstract
Insulin and insulin-like growth factors (IGFs) have critical functions in growth regulatory signalling pathways. They are part of a tightly controlled network of ligands, receptors, binding proteins and their proteases. However, the system becomes uncontrolled in neoplasia. The insulin-like growth factor binding protein 3 (IGFBP-3) and the insulin-like growth factor binding protein-related protein 1 (IGFBP-rP1) have unique properties among the sixteen known members of the IGFBP superfamily. IGFBP-3 has very high affinity for IGFs (k(d) approximately 10(-10) M), it transports >75% of serum IGF-I and -II, whereas it's affinity for insulin is very low. On the other hand, IGFBP-rP1 binds insulin with very high affinity (500-fold higher compared to other IGFBPs), but has low affinity for IGF-I and -II proteins (k(d) = 3 x 10(-8) M). In this review, we have examined the roles of IGFBP-3 and IGFBP-rP1 in breast cancer, and discuss the potential impact of these two proteins in mammary carcinoma risk assessment and the development of treatments for breast cancer.
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Affiliation(s)
- Angelika M Burger
- Laboratory of Molecular Pathology, Department of Anatomic Pathology and Division of Molecular and Cellular Biology, Sunnybrook and Women's College Health Sciences Centre, Toronto, Ont., Canada.
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40
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Hong C, Maunakea A, Jun P, Bollen AW, Hodgson JG, Goldenberg DD, Weiss WA, Costello JF. Shared epigenetic mechanisms in human and mouse gliomas inactivate expression of the growth suppressor SLC5A8. Cancer Res 2005; 65:3617-23. [PMID: 15867356 DOI: 10.1158/0008-5472.can-05-0048] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Tumors arise in part from the deleterious effects of genetic and epigenetic mechanisms on gene expression. In several mouse models of human tumors, the tumorigenic phenotype is reversible, suggesting that epigenetic mechanisms also contribute significantly to tumorigenesis in mice. It is not known whether these are the same epigenetic mechanisms in human and mouse tumors or whether they affect homologous genes. Using an integrated approach for genome-wide methylation and copy number analyses, we identified SLC5A8 on chromosome 12q23.1 that was affected frequently by aberrant methylation in human astrocytomas and oligodendrogliomas. SLC5A8 encodes a sodium monocarboxylate cotransporter that was highly expressed in normal brain but was significant down-regulated in primary gliomas. Bisulfite sequencing analysis showed that the CpG island was unmethylated in normal brain but frequently localized methylated in brain tumors, consistent with the tumor-specific loss of gene expression. In glioma cell lines, SLC5A8 expression was also suppressed but could be reactivated with a methylation inhibitor. Expression of exogenous SLC5A8 in LN229 and LN443 glioma cells inhibited colony formation, suggesting that it may function as a growth suppressor in normal brain cells. Remarkably, 9 of 10 murine oligodendroglial tumors (from p53+/- or ink4a/arf+/- animals transgenic for S100beta-v-erbB) showed a similar tumor-specific down-regulation of mSLC5A8, the highly conserved mouse homologue. Taken together, these data suggest that SLC5A8 functions as a growth suppressor gene in vitro and that it is silenced frequently by epigenetic mechanisms in primary gliomas. The shared epigenetic inactivation of mSLC5A8 in mouse gliomas indicates an additional degree of commonality in the origin and/or pathway to tumorigenesis between primary human tumors and these mouse models of gliomas.
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Affiliation(s)
- Chibo Hong
- Department of Neurological Surgery, Brain Tumor Research Center, University of California-San Francisco, San Francisco, California 94143-0875, USA
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41
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Bonner AE, Wang Y, You M. Gene expression profiling of mouse teratocarcinomas uncovers epigenetic changes associated with the transformation of mouse embryonic stem cells. Neoplasia 2005; 6:490-502. [PMID: 15548357 PMCID: PMC1531652 DOI: 10.1593/neo.04124] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The molecular mechanisms of the development of teratocarcinomas from stem cells are largely unknown. To determine which genes are associated with the transformation of these cells, we have performed oligonucleotide microarray analysis, using Affymetrix U74A GeneChips, on both cell cultures and tumors in nude mice. We identified 68 genes that significantly differed in expression between the ES cell culture and the teratocarcinoma cell line, SCC-PSA1, and 51 genes with statistically different expression patterns between the ES cell tumors and the teratocarcinomas (P < .00005). We found that there were 20 genes that had common expression patterns in both groups. We also examined the role of the transition from in vitro to in vivo by comparing ES cell culture to ES cell tumor, and teratocarcinoma cell line to teratocarcinomas. We identified 22 genes that were upregulated in the ES cell tumors and 42 that had a decreased expression in the tumor (P < .0001). In comparing SCC-PSA1 to its tumor, we identified 34 upregulated genes and 25 downregulated genes (P < .001). There were only 10 genes in common from these two lists. GenMapp search revealed that several pathways, especially the cell cycle pathway, are actively involved in the induction of teratocarcinomas. Our results indicate that many key development genes may play a key role in the transformation of ES cells into teratocarcinoma cells.
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Affiliation(s)
- Allison E Bonner
- Division of Human Cancer Genetics, The Ohio State University Comprehensive Cancer Center, 420 West 12th Avenue, Columbus, OH 43210, USA
| | - Yian Wang
- Department of Surgery and The Alvin J. Siteman Cancer Center, Campus Box 8109, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Ming You
- Department of Surgery and The Alvin J. Siteman Cancer Center, Campus Box 8109, Washington University School of Medicine, St. Louis, MO 63110, USA
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Drivdahl R, Haugk KH, Sprenger CC, Nelson PS, Tennant MK, Plymate SR. Suppression of growth and tumorigenicity in the prostate tumor cell line M12 by overexpression of the transcription factor SOX9. Oncogene 2004; 23:4584-93. [PMID: 15077158 DOI: 10.1038/sj.onc.1207603] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Overexpression of mac25 in the prostate cancer cell line M12 effects a dramatic reversal of the transformed phenotype. cDNA array analysis of RNA from cells overproducing the mac25 protein (M12/mac25) indicated upregulation of the sex determining transcription factor SOX9. In this study, we have confirmed increased expression of SOX9 in M12/mac25 cells and have further investigated the physiological effects of increased SOX9 production. Greatly increased levels of SOX9 RNA and mature protein were demonstrated in cells transfected with a SOX9 cDNA (M12/SOX9), and gel mobility shift assays confirmed binding of nuclear protein from these cells to an oligonucleotide containing the SOX9 consensus binding sequence. M12/SOX9 cells assumed the spindle-shaped morphology characteristic of M12/mac25 cells, suggesting that SOX9 mediates some effects of mac25. Elevated expression of SOX9 resulted in a decreased rate of cellular proliferation, cell cycle arrest in G0/G1, and increased sensitivity to apoptosis. Tumor development in athymic nude mice was inhibited by 80%. Finally, prostate-specific antigen and the androgen receptor, two genes whose expression is characteristic of differentiated cells, were both upregulated in M12/SOX9 cells. These data indicate that SOX9 contributes to growth regulation by mac25 via inhibition of cell growth and promotion of differentiation.
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Affiliation(s)
- Rolf Drivdahl
- Veterans Affairs Puget Sound Health Care System, Seattle, WA 98105, USA
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Symmans WF, Ayers M, Clark EA, Stec J, Hess KR, Sneige N, Buchholz TA, Krishnamurthy S, Ibrahim NK, Buzdar AU, Theriault RL, Rosales MFM, Thomas ES, Gwyn KM, Green MC, Syed AR, Hortobagyi GN, Pusztai L. Total RNA yield and microarray gene expression profiles from fine-needle aspiration biopsy and core-needle biopsy samples of breast carcinoma. Cancer 2003; 97:2960-71. [PMID: 12784330 DOI: 10.1002/cncr.11435] [Citation(s) in RCA: 144] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
BACKGROUND Gene expression profiling should be applicable to needle biopsy samples if microarray technology is to become practically useful for clinical research or management of breast carcinoma. This study compared gene expression profiles derived from fine-needle aspiration biopsy (FNAB) and from core needle biopsy (CBX). METHODS Total RNA was extracted from single FNAB and CBX samples. Corresponding pairs of FNAB and CBX were analyzed for similarity of gene expression profiles using cDNA microarrays that contain 30721 human sequences. A subset of genes that distinguished CBX samples from FNAB samples was evaluated in a larger group of needle biopsy samples and in a published genomic database derived from 78 sporadic breast carcinomas with known clinical outcome. RESULTS Sixty-eight patients with newly diagnosed breast carcinoma were included in the current study. Sixty-five patients underwent FNAB (17 had both FNAB and CBX) and 3 underwent CBX only. Extracted RNA was of suitable quality for hybridization in 46 (71%) FNABs and 15 (75%) CBXs. Total RNA yield in those samples was similar for single-pass FNAB (mean = 3.6 microg and median = 2.2 microg; n = 46) and CBX (mean = 2.8 microg and median = 2.0 microg; n = 15), with 1 microg or more of total RNA in all cases. Transcriptional profiling was performed successfully in all cases when it was attempted, in a total of 50 samples (38 FNABs and 12 CBXs), including matched FNAB and CBX samples from 10 patients. There were differences in gene expression profiles in 10 matched FNAB and CBX sample pairs. Genes that were expressed differently in CBX samples, compared with FNAB samples, were recognized as being predominantly from the endothelium, fibroblasts, myofibroblasts or smooth muscle, and histiocytes. Corresponding microscopic cell counts from FNABs demonstrated means of 80% tumor cells, 15% lymphocytes, and 5% stromal cells, whereas CBXs contained 50% tumor cells, 20% lymphocytes, and 30% stromal cells. Considering that CBXs are approximately six-fold richer in nonlymphoid stromal cells than FNABs and that CBXs differentially express a set of recognized stromal genes, the authors used these biopsies to define a transcriptional profile of breast carcinoma stroma. A set of 120 genes differentially expressed in CBXs was assessed independently in a published breast carcinoma genomic database to classify breast carcinomas based on stromal gene expression. Subgroups of tumors with low or high stromal signal were identified, but there was no correlation with the development of systemic metastases within 5 years. CONCLUSIONS Both FNAB and CBX yield a similar quality and quantity of total RNA and are suitable for cDNA microarray analyses in approximately 70-75% of single-pass samples. Transcriptional profiles from FNAB and CBX of the same tumor generally are similar and are driven by the tumor cell population. The authors concluded that each technique has relative advantages. The FNABs provide transcriptional profiles that are a purer representation of the tumor cell population, whereas transcriptional profiles from CBXs include more representation from nonlymphoid stromal elements. Selection of the preferred needle biopsy sampling technique for genomic studies of breast carcinomas should depend on whether variable stromal gene expression is desirable in the samples.
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Affiliation(s)
- W Fraser Symmans
- Department of Pathology, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030, USA.
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Rush LJ, Plass C. Restriction landmark genomic scanning for DNA methylation in cancer: past, present, and future applications. Anal Biochem 2002; 307:191-201. [PMID: 12202234 DOI: 10.1016/s0003-2697(02)00033-7] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The field of molecular biology was revolutionized by the advent of gel electrophoresis. Restriction landmark genomic scanning (RLGS) is a type of two-dimensional electrophoresis employed in the genome-wide assessment of genomic alterations. RLGS has been used to study genetic and epigenetic changes in normal tissues, primary tumors, cancer cell lines, and various organisms such as mice, rats, hamsters, bacteria, and plants. An RLGS profile displays over 2000 radiolabeled restriction landmark sites in a single assay. When conducted with methylation-sensitive restriction enzymes whose sites are preferentially located in CpG island regulatory regions, RLGS becomes a very versatile tool for the investigation of both normal and aberrant methylation patterns. Early studies performed on tumor DNA were mainly descriptive in nature, essentially a catalogue of loci that were changed to varying degrees in different tumor types. Over time, as investigators have become more proficient with RLGS and have undertaken high-throughput studies, the need for efficient cloning, imaging, and analysis systems has become paramount. Current studies focus on identifying specific genes and pathways involved in deregulated methylation in cancer. As such, RLGS analysis of tumor samples has made tremendous contributions to our understanding of the role of DNA methylation in cancer. Future directions will take advantage of the abundant genomic sequence data available to link all of the RLGS loci to genes and create biologically relevant methylation profiles of cancer. This review discusses practical considerations of using RLGS as a genome scanning tool and the past, present, and future applications in cancer biology.
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Affiliation(s)
- Laura J Rush
- Department of Veterinary Biosciences, Division of Human Cancer Genetics, The Ohio State University, Columbus, OH 43210, USA.
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Abstract
Knowledge about breast carcinogenesis has accumulated during the last decades but has barely been translated into strategies for early detection or prevention of this common disease. Changes in DNA methylation have been recognized as one of the most common molecular alterations in human neoplasia and hypermethylation of gene-promoter regions is being revealed as one of the most frequent mechanisms of loss of gene function. The heritability of methylation states and the secondary nature of the decision to attract or exclude methylation support the idea that DNA methylation is adapted for a specific cellular memory. According to Hanahan and Weinberg, there are six novel capabilities a cell has to acquire to become a cancer cell: limitless replicative potential, self-sufficiency in growth signals, insensitivity to growth-inhibitory signals, evasion of programmed cell death, sustained angiogenesis and tissue invasion and metastasis. This review highlights how DNA-methylation contributes to these features and offers suggestions about how these changes could be prevented, reverted or used as a 'tag' for early detection of breast cancer or, preferably, for detection of premalignant changes.
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Affiliation(s)
- Martin Widschwendter
- USC/Norris Comprehensive Cancer Center, Keck School of Medicine of the University of Southern California, 1441 Eastlake Avenue, MS 8302L, Los Angeles, California, CA 90089-9181, USA.
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Smiraglia DJ, Plass C. The study of aberrant methylation in cancer via restriction landmark genomic scanning. Oncogene 2002; 21:5414-26. [PMID: 12154404 DOI: 10.1038/sj.onc.1205608] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Restriction landmark genomic scanning (RLGS) has been used to study DNA methylation in cancer for nearly a decade. The strong bias of RLGS for assessing the methylation state of CpG islands genome wide makes this an attractive technique to study both hypo- and hypermethylation of regions of the genome likely to harbor genes. RLGS has been used successfully to identify regions of hypomethylation, candidate tumor suppressor genes, correlations between hypermethylation events and clinical factors, and quantification of hypermethylation in a multitude of malignancies. This review will examine the major uses of RLGS in the study of aberrant methylation in cancer and discuss the significance of some of the findings.
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Affiliation(s)
- Dominic J Smiraglia
- Division of Human Cancer Genetics, Department of Molecular Virology, Immunology and Medical Genetics, The Ohio State University, Columbus, Ohio, OH 43210, USA.
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Sprenger CC, Vail ME, Evans K, Simurdak J, Plymate SR. Over-expression of insulin-like growth factor binding protein-related protein-1(IGFBP-rP1/mac25) in the M12 prostate cancer cell line alters tumor growth by a delay in G1 and cyclin A associated apoptosis. Oncogene 2002; 21:140-7. [PMID: 11791184 DOI: 10.1038/sj.onc.1205021] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2001] [Revised: 09/12/2001] [Accepted: 10/02/2001] [Indexed: 11/09/2022]
Abstract
In the present study, we examined the effects of over-expression of the potential tumor suppressor gene IGFBP-rP1/mac25 on cell-cycle kinetics in prostate cancer cells. The majority of the high expressing IGFBP-rP1/mac25 cell population was located in the G1 and sub-G0/G1 peaks; synchronizing cells in G2/M with nocodazole demonstrated the high expressing IGFBP-rP1/mac25 clones were delayed in the G1 phase of the cell cycle. Unscheduled expression of cyclin A in the sub-G0/G1 peak occurred in the IGFBP-rP1/mac25 clones. Immunoblots showed decreased cyclin D1 and p21 and increased cyclin E, p16, and p27 in the high expressing IGFBP-rP1/mac25 clones compared to the control cells. Cyclin D1/cdk-4,6 and cyclin E/cdk-2 kinase activities decreased but cyclin A/cdk-2 kinase activity increased for the high expressing IGFBP-rP1/mac25 clones compared to control cells. A pRb immunoprecipitation demonstrated more binding of E2F-1 to pRb in the high expressing IGFBP-rP1/mac25 clones than in control cells. Finally, cell senescence, as assessed by senescence-associated beta-galactosidase, demonstrated significantly more staining in the IGFBP-rP1/mac25 cells than control cells. These results suggest that IGFBP-rP1/mac25 alters the cell cycle kinetics of the M12 prostate cell line by delaying the cells in the G1 phase of the cell cycle. In addition, the appearance of cyclin A in the sub-G0/G1 phase of the cell cycle and the increased kinase activity of cyclin A/cdk-2 in the IGFBP-rP1/mac25 clones suggests that cyclin A is associated with the apoptotic cells.
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Affiliation(s)
- Cynthia C Sprenger
- Geriatric Research Education and Clinical Center, VAPSHCS, Seattle/Tacoma, Washington, WA 98493, USA
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48
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Luo MJ, Lai MD. Identification of differentially expressed genes in normal mucosa, adenoma and adenocarcinoma of colon by SSH. World J Gastroenterol 2001; 7:726-31. [PMID: 11819864 PMCID: PMC4695584 DOI: 10.3748/wjg.v7.i5.726] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To construct subtracted cDNA libraries and further identify differentially expressed genes that are related to the development of colorectal carcinoma (CRC).
METHODS: Suppression subtractive hybridization (SSH) was done on cDNAs of normal mucosa, adenoma and adenocarcinoma tissues from the same patient. Three subtracted cDNA libraries were constructed and then hybridized with forward and backward subtracted probes for differential screening. Positive clones from each subtracted cDNA library were selected for sequencing and BLAST analysis. Finally, virtual Northern Blot confirmed such differential expression.
RESULTS: By this way, there were about 3-4 × 102 clones identified in each subtracted cDNA library, in which about 85% positive clones were differentially screened. Sequencing and BLAST homology search revealed some clones containing sequences of known gene fragments and several possibly novel genes showing few or no sequence homologies with any known sequences in the database.
CONCLUSION: All results confirmed the effectiveness and sensitivity of SSH. The differentially expressed genes during the development of CRC can be used to shed light on the pathogenesis of CRC and be useful genetic markers for early diagnosis and therapy.
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Affiliation(s)
- M J Luo
- Department of Pathology, School of Medicine, Zhejiang University, Hangzhou 310031, China
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Landberg G, Ostlund H, Nielsen NH, Roos G, Emdin S, Burger AM, Seth A. Downregulation of the potential suppressor gene IGFBP-rP1 in human breast cancer is associated with inactivation of the retinoblastoma protein, cyclin E overexpression and increased proliferation in estrogen receptor negative tumors. Oncogene 2001; 20:3497-505. [PMID: 11429696 DOI: 10.1038/sj.onc.1204471] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2001] [Revised: 03/01/2001] [Accepted: 03/15/2001] [Indexed: 12/31/2022]
Abstract
The complex insulin-like growth factor network of ligands, receptors and binding proteins has been shown to be disturbed in breast cancer. In addition to defects in proteins controlling cell cycle checkpoints, this type of aberrations could affect tumor growth and survival thereby influencing both tumor aggressiveness and potential response to treatments. We have previously identified the T1A12/mac25 protein, which is identical to the IGFBP-rP1, as a differentially expressed gene product in breast cancer cells compared with normal cells. Here we compare the expression of IGFBP-rP1 in 106 tumor samples with known status of cell cycle aberrations and other clinicopathological data. This was done using a tumor tissue section array system that allows for simultaneous immunohistochemical staining of all samples in parallel. Cytoplasmic staining of variable intensity was observed in most tumors, 15% lacked IGFBP-rP1 staining completely, 20% had weak staining, 32% intermediate and 33% showed strong staining. Low IGFBP-rP1 was associated with high cyclin E protein content, retinoblastoma protein (pRb) inactivation, low bcl-2 protein, poorly differentiated tumors and higher stage. There was a significantly impaired prognosis for patients with low IGFBP-rP1 protein tumors. Interestingly, IGFBP-rP1 showed an inverse association with proliferation (Ki-67%) in estrogen receptor negative tumors as well as in cyclin E high tumors suggesting a separate cell cycle regulatory function for IGFBP-rP1 independent of interaction with the estrogen receptor or the pRb pathway.
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MESH Headings
- Aneuploidy
- Biomarkers, Tumor/analysis
- Biomarkers, Tumor/genetics
- Breast Neoplasms/genetics
- Breast Neoplasms/pathology
- Carrier Proteins/analysis
- Carrier Proteins/genetics
- Cell Cycle/genetics
- Cell Cycle/physiology
- Cyclin D1/analysis
- Cyclin E/analysis
- Diploidy
- Female
- Gene Expression Regulation, Neoplastic
- Genes, Tumor Suppressor
- Genes, bcl-2
- Genes, erbB-2
- Genes, p53
- Humans
- Immunohistochemistry
- Insulin-Like Growth Factor Binding Proteins
- Lymphatic Metastasis
- Menopause
- Neoplasm Invasiveness
- Neoplasm Staging
- Polymorphism, Single-Stranded Conformational
- Prognosis
- Receptors, Estrogen/analysis
- Receptors, Progesterone/analysis
- Retinoblastoma Protein/metabolism
- Telomerase/analysis
- Tumor Suppressor Protein p53/analysis
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Affiliation(s)
- G Landberg
- Division of Pathology, Department of Laboratory Medicine, Lund University, Malmö University Hospital, Malmö, Sweden
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50
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Kanemitsu N, Kato MV, Miki T, Komatsu S, Okazaki Y, Hayashizaki Y, Sakai T. Characterization of the promoter of the murine mac25 gene. Biochem Biophys Res Commun 2000; 279:251-7. [PMID: 11112448 DOI: 10.1006/bbrc.2000.3944] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
It is important to know the regulation of the expression of the mac25 gene because of its reduced expression in several cancer cells and of its induction by some hormonal factors. We cloned the promoter region of the murine mac25 gene and found five repeats of CCAAT sequences, four Sp1 sites, a TATA-like sequence, and an initiator (INR) sequence. Analysis using luciferase reporter plasmids indicated that CCAAT repeats have a strong enhancer activity and the second to fourth Sp1 sites are essential for basal activity of the expression of the mac25 gene. The 1 kb region that contains the promoter and exon 1 of the mac25 gene was in a typical CpG island. As hypermethylation and reduced expression of the mac25 gene were reported in murine liver tumors, methylation of this CpG island may be directly associated with the expression of the mac25 gene and tumorigenesis.
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Affiliation(s)
- N Kanemitsu
- Department of Preventive Medicine, Kyoto Prefectural University of Medicine, Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto 602-8566, Japan
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