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Tang Y, Hong F, Ding S, Yang J, Zhang M, Ma Y, Zheng Q, Yang D, Jin Y, Ma C. METTL3-mediated m 6A modification of IGFBP7-OT promotes osteoarthritis progression by regulating the DNMT1/DNMT3a-IGFBP7 axis. Cell Rep 2023; 42:112589. [PMID: 37270777 DOI: 10.1016/j.celrep.2023.112589] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 03/15/2023] [Accepted: 05/16/2023] [Indexed: 06/06/2023] Open
Abstract
Osteoarthritis (OA) is the most common degenerative disorder, affecting approximately half of the elderly population. In this study, we find that the expressions of long noncoding RNA (lncRNA) IGFBP7-OT and its maternal gene, IGFBP7, are upregulated and positively correlated in osteoarthritic cartilage. Overexpression of IGFBP7-OT significantly inhibits chondrocyte viability, promotes chondrocyte apoptosis, and reduces extracellular matrix components, whereas IGFBP7-OT knockdown has the opposite effects. IGFBP7-OT overexpression promotes cartilage degeneration and markedly aggravates the monosodium iodoacetate-induced OA phenotype in vivo. Further mechanistic research reveals that IGFBP7-OT promotes OA progression by upregulating IGFBP7 expression. Specifically, IGFBP7-OT suppresses the occupancy of DNMT1 and DNMT3a on the IGFBP7 promoter, thereby inhibiting methylation of the IGFBP7 promoter. The upregulation of IGFBP7-OT in OA is partially controlled by METTL3-mediated N6-methyladenosine (m6A) modification. Collectively, our findings reveal that m6A modification of IGFBP7-OT promotes OA progression by regulating the DNMT1/DNMT3a-IGFBP7 axis and provide a potential therapeutical target for OA treatment.
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Affiliation(s)
- Yuting Tang
- Department of Medical Genetics, Nanjing Medical University, Longmian Road 101, Nanjing 211166, P.R. China; Jiangsu Key Laboratory of Xenotransplantation, Nanjing Medical University, Longmian Road 101, Nanjing 211166, P.R. China
| | - Fangling Hong
- Department of Medical Genetics, Nanjing Medical University, Longmian Road 101, Nanjing 211166, P.R. China; Jiangsu Key Laboratory of Xenotransplantation, Nanjing Medical University, Longmian Road 101, Nanjing 211166, P.R. China
| | - Siyang Ding
- Department of Medical Genetics, Nanjing Medical University, Longmian Road 101, Nanjing 211166, P.R. China
| | - Jiashu Yang
- Department of Medical Genetics, Nanjing Medical University, Longmian Road 101, Nanjing 211166, P.R. China
| | - Ming Zhang
- Department of Medical Genetics, Nanjing Medical University, Longmian Road 101, Nanjing 211166, P.R. China
| | - Yunfei Ma
- Department of Medical Genetics, Nanjing Medical University, Longmian Road 101, Nanjing 211166, P.R. China
| | - Que Zheng
- Department of Medical Genetics, Nanjing Medical University, Longmian Road 101, Nanjing 211166, P.R. China
| | - Dawei Yang
- Department of Orthopaedic Surgery, Nanjing First Hospital, Nanjing, P.R. China
| | - Yucui Jin
- Department of Medical Genetics, Nanjing Medical University, Longmian Road 101, Nanjing 211166, P.R. China; Jiangsu Key Laboratory of Xenotransplantation, Nanjing Medical University, Longmian Road 101, Nanjing 211166, P.R. China.
| | - Changyan Ma
- Department of Medical Genetics, Nanjing Medical University, Longmian Road 101, Nanjing 211166, P.R. China; Jiangsu Key Laboratory of Xenotransplantation, Nanjing Medical University, Longmian Road 101, Nanjing 211166, P.R. China.
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2
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Pradeepa, Suresh V, Singh VK, Nayak KB, Senapati S, Chakraborty S. EVI1 promotes metastasis by downregulating TIMP2 in metastatic colon and breast cancer cells. Int J Biochem Cell Biol 2022; 142:106118. [PMID: 34800694 DOI: 10.1016/j.biocel.2021.106118] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 10/30/2021] [Accepted: 11/08/2021] [Indexed: 10/19/2022]
Abstract
Ecotropic viral integration site-1 (EVI1) is an oncogenic zinc finger transcription factor whose expression is frequently upregulated in a variety of cancers, including both myeloid malignancies and solid tumors. Previously, our group has shown that EVI1 knockdown minimizes the metastatic potential of colon cancer cells compared to that of control cells. In this study, to identify the potential targets that regulate cancer metastasis, control and EVI1 knockdown colon cancer cells were subjected to microarray. Differential gene expression analysis revealed significant downregulation of tissue inhibitor of matrix metalloproteinase-2 (TIMP2) in EVI1 expressing cells. EVI1 knockdown increased TIMP2 protein expression levels and reduced wound healing and migration capacity in metastatic cells. Mechanistically, the TIMP2 promoter harbors potential binding sites for EVI1; EVI1 binds to TIMP2 promoter and represses its expression, as observed using ChIP and luciferase assay, respectively. TIMP2 is an important metastasis suppressor gene; however, its function is suppressed in many cancers through hypermethylation. Thus, demethylation could prove to be a potential alternative to reactivate TIMP2 functional activity. Immunoprecipitation analysis showed that DNA-methyltransferase 1 (DNMT1), which plays a vital role in maintaining the genome methylation pattern during DNA replication and repair, interacts with EVI1 to promote TIMP2 silencing. Treating cancer cells in vitro with a known demethylation agent, 5-aza-2'-deoxycytidine (Aza-D), restored the optimal TIMP2 expression without altering EVI1 binding efficiency and reduced relative wound healing potential of cancer cells. Animal studies showed that Aza-D treated cells injected through the intravenous route exhibited reduced liver and skin metastasis when compared to non-treated cells. Furthermore, Aza-D treatment in mice delayed the metastasis progression compared to the vehicle treated group. Thus, the present study provides an insight into the therapeutic applications of demethylating agents to reduce cancer metastasis in models with EVI1 overexpressing tumors.
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Affiliation(s)
- Pradeepa
- Cancer Biology Group, Institute of Life Sciences, Nalco Square, Bhubaneswar, Odisha 751023, India
| | - Voddu Suresh
- Tumor Microenvironment and Animal Models Group, Institute of Life Sciences, Nalco Square, Bhubaneswar 751023, India
| | - Vivek Kumar Singh
- Cancer Biology Group, Institute of Life Sciences, Nalco Square, Bhubaneswar, Odisha 751023, India
| | - Kasturi Bala Nayak
- Cancer Biology Group, Institute of Life Sciences, Nalco Square, Bhubaneswar, Odisha 751023, India
| | - Shantibhusan Senapati
- Tumor Microenvironment and Animal Models Group, Institute of Life Sciences, Nalco Square, Bhubaneswar 751023, India
| | - Soumen Chakraborty
- Cancer Biology Group, Institute of Life Sciences, Nalco Square, Bhubaneswar, Odisha 751023, India.
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3
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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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4
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Kim J, Kim WH, Byeon SJ, Lee BL, Kim MA. Epigenetic Downregulation and Growth Inhibition of IGFBP7 in Gastric Cancer. Asian Pac J Cancer Prev 2018; 19:667-675. [PMID: 29580038 PMCID: PMC5980839 DOI: 10.22034/apjcp.2018.19.3.667] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Background: Insulin-like growth factor-binding protein 7 (IGFBP7) has been found to be a tumor suppressor in several human cancers, but the role of IGFBP7 in gastric cancer has not yet been fully investigated. Herein, we examined the epigenetic downregulation of IGFBP7 expression in gastric cancer. Methods: Expression and methylation of IGFBP7 in gastric cancer cells and primary gastric cancer patients were determined using qRT-PCR, western blot, immunohistochemistry, and methylation specific-PCR, respectively. The effects of IGFBP7 on gastric cancer cells were investigated by various experimental conditions, such as proliferation, colony formation, apoptosis, invasion, and migration assay. Results: IGFBP7 methylation was inversely correlated with IGFBP7 expression in gastric cancer. Univariate and multivariate analysis showed that IGFBP7 expression and tumor stage were independent prognostic factors. IGFBP7 knockdown increased gastric cancer cell growth, invasion, and migration, whereas IGFBP7 overexpression in gastric cancer cells induced cell growth inhibition and apoptosis. Conclusion: Our data suggest that IGFBP7 functions as a tumor suppressor in gastric cancer via an epigenetic pathway.
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Affiliation(s)
- Jin Kim
- Cancer Research Institute, Seoul National University College of Medicine, Seoul, Korea.,Department of Pathology, Seoul National University College of Medicine, Seoul, Korea.
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5
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Murcia O, Jover R, Egoavil C, Perez-Carbonell L, Juárez M, Hernández-Illán E, Rojas E, Alenda C, Balaguer F, Andreu M, Llor X, Castells A, Boland CR, Goel A. TFAP2E Methylation and Expression Status Does Not Predict Response to 5-FU-based Chemotherapy in Colorectal Cancer. Clin Cancer Res 2018. [PMID: 29535127 DOI: 10.1158/1078-0432.ccr-17-2940] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Purpose: A recent study reported that 5-fluorouracil (5-FU)-based chemotherapy is less effective in treating patients with advanced colorectal cancer demonstrating hypermethylation of the TFAP2E gene. The aim of our study was to confirm and validate these findings in large, uniformly treated, well-characterized patient cohorts.Experimental Design: Two cohorts of 783 patients with colorectal cancer: 532 from a population-based, multicenter cohort (EPICOLON I) and 251 patients from a clinic-based trial were used to study the effectiveness of TFAP2E methylation and expression as a predictor of response of colorectal cancer patients to 5-FU-based chemotherapy. DNA methylation status of the TFAP2E gene in patients with colorectal cancer was assessed by quantitative bisulfite pyrosequencing analysis. IHC analysis of the TFAP2E protein expression was also performed.Results: Correlation between TFAP2E methylation status and IHC staining was performed in 607 colorectal cancer samples. Among 357 hypermethylated tumors, only 141 (39.6%) exhibited loss of protein expression. Survival was not affected by TFAP2E hypermethylation in stage IV patients [HR, 1.21; 95% confidence interval (CI), 0.79-1.87; log-rank P = 0.6]. In stage II-III cases, disease-free survival was not influenced by TFAP2E hypermethylation status in 5-FU-treated (HR, 0.91; 95% CI, 0.52-1.59; log-rank P = 0.9) as well as in nontreated patients (HR, 0.88; 95% CI, 0.5-1.54; log-rank P = 0.7).Conclusions:TFAP2E hypermethylation does not correlate with loss of its protein expression. Our large, systematic, and comprehensive study indicates that TFAP2E methylation and expression may not play a major role in predicting response to 5-FU-based chemotherapy in patients with colorectal cancer. Clin Cancer Res; 24(12); 2820-7. ©2018 AACR.
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Affiliation(s)
- Oscar Murcia
- Unidad de Gastroenterologia, Hospital General Universitario de Alicante, Instituto de Investigación Sanitaria ISABIAL, Alicante, Spain
| | - Rodrigo Jover
- Unidad de Gastroenterologia, Hospital General Universitario de Alicante, Instituto de Investigación Sanitaria ISABIAL, Alicante, Spain.
| | - Cecilia Egoavil
- Research Unit, Hospital General Universitario de Alicante, Instituto de Investigación Sanitaria ISABIAL, Alicante, Spain.,Department of Pathology, Hospital General Universitario de Alicante, Instituto de Investigación Sanitaria ISABIAL, Alicante, Spain
| | - Lucia Perez-Carbonell
- Center for Gastrointestinal Research; Center for Translational Genomics and Oncology, Baylor Scott & White Research Institute and Charles A Sammons Cancer Center, Baylor Research Institute and Sammons Cancer Center, Baylor University Medical Center, Dallas, Texas
| | - Miriam Juárez
- Research Unit, Hospital General Universitario de Alicante, Instituto de Investigación Sanitaria ISABIAL, Alicante, Spain
| | - Eva Hernández-Illán
- Research Unit, Hospital General Universitario de Alicante, Instituto de Investigación Sanitaria ISABIAL, Alicante, Spain
| | - Estefania Rojas
- Department of Pathology, Hospital General Universitario de Alicante, Instituto de Investigación Sanitaria ISABIAL, Alicante, Spain
| | - Cristina Alenda
- Department of Pathology, Hospital General Universitario de Alicante, Instituto de Investigación Sanitaria ISABIAL, Alicante, Spain
| | - Francesc Balaguer
- Gastroenterology Department, Hospital Clinic, CIBERehd, IDIBAPS, University of Barcelona, Barcelona, Spain
| | | | - Xavier Llor
- Department of Medicine, Yale University Medical Center, New Haven, Connecticut
| | - Antoni Castells
- Gastroenterology Department, Hospital Clinic, CIBERehd, IDIBAPS, University of Barcelona, Barcelona, Spain
| | - C Richard Boland
- Center for Gastrointestinal Research; Center for Translational Genomics and Oncology, Baylor Scott & White Research Institute and Charles A Sammons Cancer Center, Baylor Research Institute and Sammons Cancer Center, Baylor University Medical Center, Dallas, Texas
| | - Ajay Goel
- Center for Gastrointestinal Research; Center for Translational Genomics and Oncology, Baylor Scott & White Research Institute and Charles A Sammons Cancer Center, Baylor Research Institute and Sammons Cancer Center, Baylor University Medical Center, Dallas, Texas.
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6
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Tao LP, Fan XP, Fan YC, Zhao J, Gao S, Wang K. Combined detection of insulin-like growth factor-binding protein 7 promoter methylation improves the diagnostic efficacy of AFP in hepatitis B virus-associated hepatocellular carcinoma. Pathol Res Pract 2017; 214:144-150. [PMID: 29108923 DOI: 10.1016/j.prp.2017.10.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Revised: 09/25/2017] [Accepted: 10/03/2017] [Indexed: 12/18/2022]
Abstract
This study quantitatively assessed serum insulin-like growth factor-binding protein 7 (IGFBP7) promoter methylation in hepatocellular carcinoma (HCC), and explored its clinical value. A total of 80 patients with hepatitis B virus-associated HCC, 35 patients with chronic hepatitis B (CHB), and 20 healthy controls (HC) were enrolled. MethyLight was used to quantitatively assess the methylation levels of serum IGFBP7 promoter. A logistic regression model was established for the combined evaluation of AFP and serum IGFBP7 promoter methylation. The results showed that mean methylation levels of serum IGFBP7 promoter were significantly higher in HCC (5.33%, interquartile range [IQR] 1.14-15.70%) patients than in individuals with CHB (1.54%, IQR 0.64-2.45%; P<0.01) and HC (0.63%, IQR 0.22-0.98%; P<0.01). In HCC subgroups, patients with vascular invasion, tumor size >3cm and advanced tumor node metastasis (TNM) showed higher methylation levels compared with the remaining groups (P<0.05). Compared with AFP alone, combined determination based on logistic regression analysis significantly improved the area under the receiver operating characteristic (ROC) curve (AUC) (0.759 vs 0.623, P<0.05). In addition, the Youden index was increased from 5.71%, 11.25% and 15.18%, when considering AFP alone at cut-off values of 20, 200, and 400ng/ml, respectively, to 45.71% with IGFBP7 promoter methylation taken into consideration (all P<0.05). These results suggested that combined quantitative measurement of serum IGFBP7 promoter methylation could enhance the diagnostic ability of AFP in distinguishing hepatitis B virus-associated HCC from CHB.
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Affiliation(s)
- Li-Ping Tao
- Department of Hepatology, Qilu Hospital of Shandong University, Jinan 250012, China; Department of Gastroenterology of The First Affiliated Hospital of Wenzhou Medical University, Wenzhou 325000, China
| | - Xiao-Peng Fan
- Department of Hepatology, Qilu Hospital of Shandong University, Jinan 250012, China; Institute of Hepatology, Shandong University, Jinan 250012, China
| | - Yu-Chen Fan
- Department of Hepatology, Qilu Hospital of Shandong University, Jinan 250012, China; Institute of Hepatology, Shandong University, Jinan 250012, China
| | - Jing Zhao
- Department of Hepatology, Qilu Hospital of Shandong University, Jinan 250012, China; Institute of Hepatology, Shandong University, Jinan 250012, China
| | - Shuai Gao
- Department of Hepatology, Qilu Hospital of Shandong University, Jinan 250012, China; Institute of Hepatology, Shandong University, Jinan 250012, China
| | - Kai Wang
- Department of Hepatology, Qilu Hospital of Shandong University, Jinan 250012, China; Institute of Hepatology, Shandong University, Jinan 250012, China.
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7
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Gao Y, Xu Y, Wu D, Yu F, Yang L, Yao Y, Liang Z, Lau ATY. Progressive silencing of the zinc transporter Zip8 (Slc39a8) in chronic cadmium-exposed lung epithelial cells. Acta Biochim Biophys Sin (Shanghai) 2017; 49:444-449. [PMID: 28338971 DOI: 10.1093/abbs/gmx022] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Accepted: 03/01/2017] [Indexed: 02/05/2023] Open
Abstract
Cadmium (Cd), a non-essential metal, stealthily enters the cells by utilizing the essential metal importing pathways. The zinc transporters Zip8, Zip14, and divalent metal transporter 1 (Dmt1) are now emerging as several important metal transporters involved in cellular Cd incorporation and their expressions have been shown to be down-regulated in several Cd-resistant (CdR) cell lines, however, the involvement of these transporters during the development of Cd-resistance in lung cells is unclear. In this study, we therefore check the expression of these metal transporters in our previously established rat lung epithelial cells (LECs) and show that the level of Zip8 is progressively silenced when LECs are adapted to increasing concentrations of CdCl2 (from 1 to 20 μM). Subsequent measurement of the cellular Cd content indicated that CdR LECs exhibit a marked decrease of Cd accumulation, possibly due to the loss of Zip8 expression. We investigate the possibility that epigenetic silencing of the Zip8 gene by DNA hypermethylation is involved in the down-regulation of Zip8 expression. CdR LECs show a higher mRNA level of DNA methyltransferase 3b (Dnmt3b) than parental cells. Treatment of CdR LECs with 5-aza-2'-deoxycytidine, an inhibitor of DNA methyltransferases, reverted the expression of Zip8 and sensitivity to Cd in these cells, indicating the critical role of Zip8 for Cd import. Taken together, our results demonstrate that the progressive silencing of Zip8 expression is involved in the acquisition of resistance against Cd in lung cells, representing an adaptive survival mechanism that resists Cd-induced cytotoxicity.
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Affiliation(s)
- Yangmin Gao
- Laboratory of Cancer Biology and Epigenetics, Department of Cell Biology and Genetics, Shantou University Medical College, Shantou 515041, China
| | - Yanming Xu
- Laboratory of Cancer Biology and Epigenetics, Department of Cell Biology and Genetics, Shantou University Medical College, Shantou 515041, China
| | - Dandan Wu
- Laboratory of Cancer Biology and Epigenetics, Department of Cell Biology and Genetics, Shantou University Medical College, Shantou 515041, China
| | - Feiyuan Yu
- Laboratory of Cancer Biology and Epigenetics, Department of Cell Biology and Genetics, Shantou University Medical College, Shantou 515041, China
| | - Lei Yang
- Laboratory of Cancer Biology and Epigenetics, Department of Cell Biology and Genetics, Shantou University Medical College, Shantou 515041, China
| | - Yue Yao
- Laboratory of Cancer Biology and Epigenetics, Department of Cell Biology and Genetics, Shantou University Medical College, Shantou 515041, China
| | - Zhanling Liang
- Laboratory of Cancer Biology and Epigenetics, Department of Cell Biology and Genetics, Shantou University Medical College, Shantou 515041, China
| | - Andy T Y Lau
- Laboratory of Cancer Biology and Epigenetics, Department of Cell Biology and Genetics, Shantou University Medical College, Shantou 515041, China
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8
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Karabulut S, Kaya Z, Amuran GG, Peker I, Özmen T, Gūllūoḡlu BM, Kaya H, Erzik C, Ōzer A, Akkiprik M. Correlation between the DNA methylation and gene expression of IGFBP5 in breast cancer. Breast Dis 2017; 36:123-131. [PMID: 27612043 DOI: 10.3233/bd-160234] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
BACKGROUND The insulin-like growth factor binding protein5 (IGFBP5) is often dysregulated in human cancers and considered neither a tumor suppressor nor an oncogene. OBJECTIVE We aim to examine the reason of the changeable gene regulation of IGFBP5 in the case of methylation in breast cancer. METHODS We used methyl-specific polymerase (MSP) chain reaction to detect CpG methylation of IGFBP5 promoter and exon-I in breast cancer and adjacent tissues. Gene expression is evaluated by quantative polymerase chain reaction (qPCR). RESULTS IGFBP5 methylation was detected in 24 of 58 (41%) and 54 of 56 (96.5%) promoter and exon-I site respectively in tumor tissues. In adjacent tissues 17 of 58 (29%) and 53 of 56 (96.5%) was methylated. IGFBP5 expression was higher estrogene receptor (ER)(+) than ER(-) patients (p = 0.0549). Beside, we found a positive correlation between the expression of IGFBP5 and G2 tumor grade (p = 0.0131). However, no correlation was observed between IGFBP5 expression and age, menopause or the presence of lymph node metastasis (p > 0.05). CONCLUSIONS In summary, our results showed that IGFBP5 promoter and exon-I methylation did not have any differences between tumor and adjacent tissues so that IGFBP5 methylation did not change IGFBP5 gene regulation in breast cancer. This is the first study investigating the IGFBP5 gene methylation in breast cancer.
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Affiliation(s)
- Sevgi Karabulut
- Marmara University, School of Medicine, Medical Biology Department, Istanbul, Turkey.,Bayburt University, Health Services Vocational School, Bayburt, Turkey
| | - Zehra Kaya
- Marmara University, School of Medicine, Medical Biology Department, Istanbul, Turkey.,Yüzüncü Yıl University, School of Medicine, Medical Biology Department, Van, Turkey
| | - Gökçe Gūllū Amuran
- Marmara University, School of Medicine, Medical Biology Department, Istanbul, Turkey
| | - Irem Peker
- Marmara University, School of Medicine, Medical Biology Department, Istanbul, Turkey
| | - Tolga Özmen
- Marmara University, School of Medicine, General Surgery Department, Istanbul, Turkey
| | - Bahadır M Gūllūoḡlu
- Marmara University, School of Medicine, General Surgery Department, Istanbul, Turkey
| | - Handan Kaya
- Marmara University, School of Medicine, Pathology Department, Istanbul, Turkey
| | - Can Erzik
- Marmara University, School of Medicine, Medical Biology Department, Istanbul, Turkey
| | - Ayşe Ōzer
- Marmara University, School of Medicine, Medical Biology Department, Istanbul, Turkey
| | - Mustafa Akkiprik
- Marmara University, School of Medicine, Medical Biology Department, Istanbul, Turkey
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9
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Chen YB, Liao XY, Zhang JB, Wang F, Qin HD, Zhang L, Shugart YY, Zeng YX, Jia WH. ADAR2 functions as a tumor suppressor via editing IGFBP7 in esophageal squamous cell carcinoma. Int J Oncol 2016; 50:622-630. [PMID: 28035363 DOI: 10.3892/ijo.2016.3823] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2016] [Accepted: 11/28/2016] [Indexed: 01/07/2023] Open
Abstract
Esophageal squamous cell carcinoma (ESCC), one of the most aggressive cancers, is characterized by heterogeneous genetic and epigenetic changes. Recently, A-to-I RNA editing, catalyzed by adenosine deaminases acting on RNA (ADARs), was found to be aberrantly regulated during tumorigenesis. We previously reported that ADAR2 was downregulated in ESCC but its role was unclear. Thus, we report here that overexpression of ADAR2 can induce apoptosis in ESCC cell lines and inhibit tumor growth in vitro and in vivo. ADAR2 knockdown inhibited apoptosis in ADAR2 highly expressing tumor cells. RNA-seq assay showed that ADAR2, not ADAR1 or active-site-mutated ADAR2, could edit insulin-like growth factor binding protein 7 (IGFBP7) mRNA in ESCC. IGFBP7 knockdown or ADAR2 catalytic activity destruction abolished the pro-apoptotic function of ADAR2. Mechanistically, RNA editing may stabilize IGFBP7 protein by changing the protease recognition site of matriptase and this is essential for IGFBP7 to induce apoptosis. Western blotting revealed that ADAR2 overexpression could induce IGFBP7-dependent inhibition of Akt signaling. Thus, our data indicate that ADAR2 suppresses tumor growth and induces apoptosis by editing and stabilizing IGFBP7 in ESCC, and this may represent a novel therapeutic target for treating ESCC.
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Affiliation(s)
- Yuan-Bin Chen
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, Guangdong 510060, P.R. China
| | - Xiao-Yu Liao
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, Guangdong 510060, P.R. China
| | - Jiang-Bo Zhang
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, Guangdong 510060, P.R. China
| | - Fang Wang
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, Guangdong 510060, P.R. China
| | - Hai-De Qin
- Unit on Statistical Genomics, Division of Intramural Research Programs, National Institute of Mental Health, National Institutes of Health, Bethesda, MD 20892, USA
| | - Lanjun Zhang
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, Guangdong 510060, P.R. China
| | - Yin Yao Shugart
- Unit on Statistical Genomics, Division of Intramural Research Programs, National Institute of Mental Health, National Institutes of Health, Bethesda, MD 20892, USA
| | - Yi-Xin Zeng
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, Guangdong 510060, P.R. China
| | - Wei-Hua Jia
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, Guangdong 510060, P.R. China
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10
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Kaya Z, Akkiprik M, Karabulut S, Peker I, Gullu Amuran G, Ozmen T, Gulluoglu BM, Kaya H, Ozer A. Comparison of telomere length and insulin-like growth factor-binding protein 7 promoter methylation between breast cancer tissues and adjacent normal tissues in Turkish women. J Clin Lab Anal 2016; 31. [PMID: 27775181 DOI: 10.1002/jcla.22083] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Accepted: 09/18/2016] [Indexed: 02/03/2023] Open
Abstract
BACKGROUND Both insulin-like growth factor-binding protein 7 (IGFBP7) and telomere length (TL) are associated with proliferation and senescence of human breast cancer. This study assessed the clinical significance of both TL and IGFBP7 methylation status in breast cancer tissues compared with adjacent normal tissues. We also investigated whether IGFBP7 methylation status could be affecting TL. METHODS Telomere length was measured by quantitative PCR to compare tumors with their adjacent normal tissues. The IGFBP7 promoter methylation status was evaluated by methylation-specific PCR and its expression levels were determined by western blotting. RESULTS Telomeres were shorter in tumor tissues compared to controls (P<.0001). The mean TL was higher in breast cancer with invasive ductal carcinoma (IDC; n=72; P=.014) compared with other histological type (n=29), and TL in IDC with HER2 negative (n=53; P=.017) was higher than TL in IDC with HER2 positive (n=19). However, telomeres were shortened in advanced stages and growing tumors. IGFBP7 methylation was observed in 90% of tumor tissues and 59% of controls (P=.0002). Its frequency was significantly higher in IDC compared with invasive mixed carcinoma (IMC; P=.002) and it was not correlated either with protein expression or the other clinicopathological parameters. CONCLUSION These results suggest that IGFBP7 promoter methylation and shorter TL in tumor compared with adjacent tissues may be predictive biomarkers for breast cancer. Telomere maintenance may be indicative of IDC and IDC with HER2 (-) of breast cancer. Further studies with larger number of cases are necessary to verify this association.
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Affiliation(s)
- Zehra Kaya
- Medical Biology Department, School of Medicine, Marmara University, Istanbul, Turkey.,Medical Biology Department, School of Medicine, Yüzüncü Yıl University, Van, Turkey
| | - Mustafa Akkiprik
- Medical Biology Department, School of Medicine, Marmara University, Istanbul, Turkey
| | - Sevgi Karabulut
- Medical Biology Department, School of Medicine, Marmara University, Istanbul, Turkey.,Health Services Vocational School, Bayburt University, Bayburt, Turkey
| | - Irem Peker
- Medical Biology Department, School of Medicine, Marmara University, Istanbul, Turkey
| | - Gokce Gullu Amuran
- Medical Biology Department, School of Medicine, Marmara University, Istanbul, Turkey
| | - Tolga Ozmen
- General Surgery, School of Medicine, Marmara University, Istanbul, Turkey
| | | | - Handan Kaya
- Pathology Department, School of Medicine, Marmara University, Istanbul, Turkey
| | - Ayse Ozer
- Medical Biology Department, School of Medicine, Marmara University, Istanbul, Turkey
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11
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Ruan W, Kang Z, Li Y, Sun T, Wang L, Liang L, Lai M, Wu T. Interaction between IGFBP7 and insulin: a theoretical and experimental study. Sci Rep 2016; 6:19586. [PMID: 27101796 PMCID: PMC4840315 DOI: 10.1038/srep19586] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2014] [Accepted: 10/14/2015] [Indexed: 12/13/2022] Open
Abstract
Insulin-like growth factor binding protein 7 (IGFBP7) can bind to insulin with high affinity which inhibits the early steps of insulin action. Lack of recognition mechanism impairs our understanding of insulin regulation before it binds to insulin receptor. Here we combine computational simulations with experimental methods to investigate the interaction between IGFBP7 and insulin. Molecular dynamics simulations indicated that His200 and Arg198 in IGFBP7 were key residues. Verified by experimental data, the interaction remained strong in single mutation systems R198E and H200F but became weak in double mutation system R198E-H200F relative to that in wild-type IGFBP7. The results and methods in present study could be adopted in future research of discovery of drugs by disrupting protein-protein interactions in insulin signaling. Nevertheless, the accuracy, reproducibility, and costs of free-energy calculation are still problems that need to be addressed before computational methods can become standard binding prediction tools in discovery pipelines.
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Affiliation(s)
- Wenjing Ruan
- Department of Pathology, School of Medicine, Zhejiang University, Hangzhou 310058, P. R. China.,Department of Respiratory Medicine, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou 310006, P.R. China
| | - Zhengzhong Kang
- Soft Matter Research Center and Department of Chemistry, Zhejiang University, Hangzhou 310027, P. R. China
| | - Youzhao Li
- Department of Pathology, School of Medicine, Zhejiang University, Hangzhou 310058, P. R. China
| | - Tianyang Sun
- Soft Matter Research Center and Department of Chemistry, Zhejiang University, Hangzhou 310027, P. R. China
| | - Lipei Wang
- Department of Pathology, School of Medicine, Zhejiang University, Hangzhou 310058, P. R. China
| | - Lijun Liang
- Soft Matter Research Center and Department of Chemistry, Zhejiang University, Hangzhou 310027, P. R. China
| | - Maode Lai
- Department of Pathology, School of Medicine, Zhejiang University, Hangzhou 310058, P. R. China
| | - Tao Wu
- Soft Matter Research Center and Department of Chemistry, Zhejiang University, Hangzhou 310027, P. R. China
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12
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Chen LH, Liu DW, Chang JL, Chen PR, Hsu LP, Lin HY, Chou YF, Lee CF, Yang MC, Wen YH, Hsu WL, Weng CF. Methylation status of insulin-like growth factor-binding protein 7 concurs with the malignance of oral tongue cancer. JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH : CR 2015; 34:20. [PMID: 25880247 PMCID: PMC4355468 DOI: 10.1186/s13046-015-0138-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Accepted: 02/16/2015] [Indexed: 01/12/2023]
Abstract
Background Aberrant insulin-like growth factor-binding protein 7 (IGFBP-7) expression has been found in various cancers such as prostate, breast, and colon. IGFBP-7 induced the apoptosis of tumor and potentially predicted the clinical outcome in some cancers is further demonstrated. This study investigates the causes and underlying mechanisms of aberrant IGFBP-7 expression in unravelling head and neck squamous cell carcinoma (HNSCC). Methods A total of 47 oral tongue cancer patient samples were primarily analyzed for the methylation status in 5′ region of IGFBP-7 by methylation-specific PCR (MS-PCR). Subsequently the invasion, overexpression, and knockdown of IGFBP-7 in the HNSCC A253 invasive subpopulation were employed to examine the effect of IGFBP-7. The epithelial–mesenchymal transition (EMT) marker genes and AKT/GSK3β/β-catenin signaling were further evaluated by Western blot for the understanding the role of aberrant IGFBP-7 expression and thereof putative mechanism. Results EMT expressed in the invasive subpopulation of HNSCC cell lines (A253 and RPMI 2650) was contemporary with the down-regulation of IGFBP-7. After treatment with 5-AZA-2′ deoxycytidine, the de-methylated CpG sites in the 5′ region of IGFBP-7 were observed and IGFBP-7 mRNA expression was also restored. Accordingly, re-expression IGFBP-7 in invasive subpopulation of A253 could induce the mesenchymal–epithelial transition (MET) and concurrently inhibited the cell invasion. Moreover, IGFBP-7 methylation status of 47 oral tongue tumors showed a positive correlation to invasive depth of the tumor, loco-regional recurrence, and cancer sequence. Conclusions IGFBP-7 can alter EMT relative marker genes and suppress cell invasion in A253 cell through AKT/GSK3β/β-catenin signaling. The epigenetic control of IGFBP-7 in the invasion and metastasis of HNSCC was reported, suggesting that IGFBP-7 could be a prognostic factor for the probability of invasion and a therapeutic remedy. Electronic supplementary material The online version of this article (doi:10.1186/s13046-015-0138-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Li-Hsuen Chen
- Department of Life Science and the Institute of Biotechnology, National Dong Hwa University, Hualien, Taiwan. .,Department of Radiation Oncology, Buddhist Tzu Chi General Hospital, Hualien, Taiwan.
| | - Dai-Wei Liu
- Department of Radiation Oncology, Buddhist Tzu Chi General Hospital, Hualien, Taiwan. .,School of Medicine, Tzu Chi University, Hualien, Taiwan.
| | - Junn-Liang Chang
- Department of Pathology and Laboratory Medicine, Taoyuan Armed Forces General Hospital, Taoyuan, Taiwan. .,Department of Biomedical Engineering, Ming Chuan University, Taoyuan, Taiwan.
| | - Peir-Rong Chen
- School of Medicine, Tzu Chi University, Hualien, Taiwan. .,Department of Otolaryngology, Buddhist Tzu Chi General Hospital, Hualien, Taiwan.
| | - Lee-Ping Hsu
- School of Medicine, Tzu Chi University, Hualien, Taiwan. .,Department of Otolaryngology, Buddhist Taichung Tzu Chi Hospital, Taichung, Taiwan.
| | - Hon-Yi Lin
- School of Medicine, Tzu Chi University, Hualien, Taiwan. .,Department of Radiation Oncology, Buddhist Dalin Tzu Chi Hospital, Chia-Yi, Taiwan.
| | - Yu-Fu Chou
- School of Medicine, Tzu Chi University, Hualien, Taiwan. .,Department of Otolaryngology, Buddhist Tzu Chi General Hospital, Hualien, Taiwan.
| | - Chia-Fong Lee
- School of Medicine, Tzu Chi University, Hualien, Taiwan. .,Department of Otolaryngology, Buddhist Tzu Chi General Hospital, Hualien, Taiwan.
| | - Miao-Chun Yang
- School of Medicine, Tzu Chi University, Hualien, Taiwan. .,Department of Otolaryngology, Buddhist Tzu Chi General Hospital, Hualien, Taiwan.
| | - Yu-Hsuan Wen
- School of Medicine, Tzu Chi University, Hualien, Taiwan. .,Department of Otolaryngology, Buddhist Tzu Chi General Hospital, Hualien, Taiwan.
| | - Wen-Lin Hsu
- Department of Radiation Oncology, Buddhist Tzu Chi General Hospital, Hualien, Taiwan. .,School of Medicine, Tzu Chi University, Hualien, Taiwan.
| | - Ching-Feng Weng
- Department of Life Science and the Institute of Biotechnology, National Dong Hwa University, Hualien, Taiwan.
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13
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Simons CCJM, van den Brandt PA, Stehouwer CDA, van Engeland M, Weijenberg MP. Body size, physical activity, early-life energy restriction, and associations with methylated insulin-like growth factor-binding protein genes in colorectal cancer. Cancer Epidemiol Biomarkers Prev 2014; 23:1852-62. [PMID: 24972776 DOI: 10.1158/1055-9965.epi-13-1285] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND We investigated body size, physical activity, and early-life energy restriction in relation to colorectal tumors with and without methylated insulin-like growth factor-binding protein (IGFBP) genes, which are putative tumor-suppressor genes. METHODS We determined IGFBP2, IGFBP3, and IGFBP7 promoter CpG island hypermethylation in tumors of 733 colorectal cancer cases from the Netherlands Cohort Study (N = 120,852). Participants self-reported lifestyle and dietary factors at baseline in 1986. Using a case-cohort approach (N subcohort = 5,000), we estimated hazard ratios (HR) for colorectal cancer by extent of IGFBP methylation. RESULTS Comparison of the highest versus lowest sex-specific tertiles of adult body mass index (BMI) gave multivariable-adjusted HRs [95% confidence intervals (CI)] for colorectal cancers with 0 (18.7%), 1 (29.5%), 2 (32.4%), and 3 (19.5%) methylated genes of 1.39 (0.88-2.19), 1.11 (0.77-1.62), 1.67 (1.17-2.38), and 2.07 (1.29-3.33), respectively. Other anthropometric measures and physical activity were not associated with colorectal cancer risk by extent of IGFBP methylation, except height in sex-specific analyses for women. Exposure to energy restriction during the Dutch Hunger Winter versus nonexposure gave HRs (95% CIs) for colorectal cancers with 0, 1, 2, and 3 methylated genes of 1.01 (0.67-1.53), 1.03 (0.74-1.44), 0.72 (0.52-0.99), and 0.50 (0.32-0.78), respectively. CONCLUSIONS Adult BMI, height (in women only), and early-life energy restriction were associated with the risk of having a colorectal tumor characterized by IGFBP methylation. IMPACT Body size may particularly increase the risk of IGFBP gene-methylated colorectal tumors; this finding might facilitate more targeted approaches to prevent obesity-related colorectal cancers.
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Affiliation(s)
- Colinda C J M Simons
- Department of Epidemiology, GROW - School for Oncology and Developmental Biology, Maastricht University, Maastricht, the Netherlands
| | - Piet A van den Brandt
- Department of Epidemiology, GROW - School for Oncology and Developmental Biology, Maastricht University, Maastricht, the Netherlands
| | - Coen D A Stehouwer
- Department of Internal Medicine, CARIM - School for Cardiovascular Diseases, Maastricht University Medical Center, Maastricht, the Netherlands
| | - Manon van Engeland
- Department of Pathology, GROW - School for Oncology and Developmental Biology, Maastricht University Medical Center, Maastricht, the Netherlands
| | - Matty P Weijenberg
- Department of Epidemiology, GROW - School for Oncology and Developmental Biology, Maastricht University, Maastricht, the Netherlands.
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14
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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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15
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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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16
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Agis-Balboa RC, Fischer A. Generating new neurons to circumvent your fears: the role of IGF signaling. Cell Mol Life Sci 2014; 71:21-42. [PMID: 23543251 PMCID: PMC11113432 DOI: 10.1007/s00018-013-1316-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2012] [Revised: 02/12/2013] [Accepted: 03/04/2013] [Indexed: 12/13/2022]
Abstract
Extinction of fear memory is a particular form of cognitive function that is of special interest because of its involvement in the treatment of anxiety and mood disorders. Based on recent literature and our previous findings (EMBO J 30(19):4071-4083, 2011), we propose a new hypothesis that implies a tight relationship among IGF signaling, adult hippocampal neurogenesis and fear extinction. Our proposed model suggests that fear extinction-induced IGF2/IGFBP7 signaling promotes the survival of neurons at 2-4 weeks old that would participate in the discrimination between the original fear memory trace and the new safety memory generated during fear extinction. This is also called "pattern separation", or the ability to distinguish similar but different cues (e.g., context). To understand the molecular mechanisms underlying fear extinction is therefore of great clinical importance.
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Affiliation(s)
- R C Agis-Balboa
- Department of Psychiatry and Psychotherapy, University Medical Center Göttingen, Grisebach Str. 5, 37077, Göttingen, Germany,
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17
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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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18
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Li F, Fan YC, Gao S, Sun FK, Yang Y, Wang K. Methylation of serum insulin-like growth factor-binding protein 7 promoter in hepatitis B virus-associated hepatocellular carcinoma. Genes Chromosomes Cancer 2013; 53:90-7. [PMID: 24142767 DOI: 10.1002/gcc.22120] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2013] [Accepted: 09/26/2013] [Indexed: 12/14/2022] Open
Affiliation(s)
- Feng Li
- Department of Hepatology; Qilu Hospital of Shandong University; Jinan China
- Institute of Hepatology; Shandong University; Jinan China
| | - Yu-Chen Fan
- Department of Hepatology; Qilu Hospital of Shandong University; Jinan China
- Institute of Hepatology; Shandong University; Jinan China
| | - Shuai Gao
- Department of Hepatology; Qilu Hospital of Shandong University; Jinan China
| | - Feng-Kai Sun
- Department of Hepatology; Qilu Hospital of Shandong University; Jinan China
| | - Yang Yang
- Department of Hepatology; Qilu Hospital of Shandong University; Jinan China
| | - Kai Wang
- Department of Hepatology; Qilu Hospital of Shandong University; Jinan China
- Institute of Hepatology; Shandong University; Jinan China
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19
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Agbemenyah HY, Agis-Balboa RC, Burkhardt S, Delalle I, Fischer A. Insulin growth factor binding protein 7 is a novel target to treat dementia. Neurobiol Dis 2013; 62:135-43. [PMID: 24075854 DOI: 10.1016/j.nbd.2013.09.011] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2013] [Revised: 08/13/2013] [Accepted: 09/17/2013] [Indexed: 12/14/2022] Open
Abstract
Alzheimer's disease (AD) is the most common form of dementia in the elderly but effective therapeutic strategies to treat AD are not yet available. This is also due to the fact that the pathological mechanisms that drive the pathogenesis of sporadic AD are still not sufficiently understood and may differ on the individual level. Several risk factors such as altered insulin-like peptide (ILP) signaling have been linked to AD and modulating the ILP system has been discussed as a potential therapeutic avenue. Here we show that insulin-like growth factor binding protein 7 (IGFBP7), a protein that attenuates the function of ILPs, is up-regulated in the brains of AD patients and in a mouse model for AD via a process that involves altered DNA-methylation and coincides with decreased ILP signaling. Mimicking the AD-situation in wild type mice, by increasing hippocampal IGFBP7 levels leads to impaired memory consolidation. Consistently, inhibiting IGFBP7 function in mice that develop AD-like memory impairment reinstates associative learning behavior. These data suggest that IGFBP7 is a critical regulator of memory consolidation and might be used as a biomarker for AD. Targeting IGFBP7 could be a novel therapeutic avenue for the treatment of AD patients.
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Affiliation(s)
- Hope Y Agbemenyah
- Department of Psychiatry and Psychotherapy, University Medical Center Göttingen, Grisebachstr. 5, 37077 Göttingen, Germany
| | - Roberto C Agis-Balboa
- Department of Psychiatry and Psychotherapy, University Medical Center Göttingen, Grisebachstr. 5, 37077 Göttingen, Germany
| | - Susanne Burkhardt
- German Center for Neurodegenerative Diseases (DZNE) Göttingen, Grisebachstr. 5, 37077 Göttingen, Germany
| | - Ivana Delalle
- Department of Pathology and Laboratory Medicine, Boston University School of Medicine, Boston, MA, USA
| | - Andre Fischer
- Department of Psychiatry and Psychotherapy, University Medical Center Göttingen, Grisebachstr. 5, 37077 Göttingen, Germany; German Center for Neurodegenerative Diseases (DZNE) Göttingen, Grisebachstr. 5, 37077 Göttingen, Germany.
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20
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Sun S, Noviski A, Yu X. MethyQA: a pipeline for bisulfite-treated methylation sequencing quality assessment. BMC Bioinformatics 2013; 14:259. [PMID: 23968174 PMCID: PMC3765750 DOI: 10.1186/1471-2105-14-259] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2013] [Accepted: 08/09/2013] [Indexed: 11/10/2022] Open
Abstract
Background DNA methylation is an epigenetic event that adds a methyl-group to the 5’ cytosine. This epigenetic modification can significantly affect gene expression in both normal and diseased cells. Hence, it is important to study methylation signals at the single cytosine site level, which is now possible utilizing bisulfite conversion technique (i.e., converting unmethylated Cs to Us and then to Ts after PCR amplification) and next generation sequencing (NGS) technologies. Despite the advances of NGS technologies, certain quality issues remain. Some of the more prevalent quality issues involve low per-base sequencing quality at the 3’ end, PCR amplification bias, and bisulfite conversion rates. Therefore, it is important to conduct quality assessment before downstream analysis. To the best of our knowledge, no existing software packages can generally assess the quality of methylation sequencing data generated based on different bisulfite-treated protocols. Results To conduct the quality assessment of bisulfite methylation sequencing data, we have developed a pipeline named MethyQA. MethyQA combines currently available open-source software packages with our own custom programs written in Perl and R. The pipeline can provide quality assessment results for tens of millions of reads in under an hour. The novelty of our pipeline lies in its examination of bisulfite conversion rates and of the DNA sequence structure of regions that have different conversion rates or coverage. Conclusions MethyQA is a new software package that provides users with a unique insight into the methylation sequencing data they are researching. It allows the users to determine the quality of their data and better prepares them to address the research questions that lie ahead. Due to the speed and efficiency at which MethyQA operates, it will become an important tool for studies dealing with bisulfite methylation sequencing data.
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Affiliation(s)
- Shuying Sun
- Department of Epidemiology and Biostatistics, Case Western Reserve University, Cleveland 44106, Ohio, USA.
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21
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van Roon EH, Boot A, Dihal AA, Ernst RF, van Wezel T, Morreau H, Boer JM. BRAF mutation-specific promoter methylation of FOX genes in colorectal cancer. Clin Epigenetics 2013; 5:2. [PMID: 23324568 PMCID: PMC3599401 DOI: 10.1186/1868-7083-5-2] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2012] [Accepted: 12/05/2012] [Indexed: 01/19/2023] Open
Abstract
Background Cancer-specific hypermethylation of (promoter) CpG islands is common during the tumorigenesis of colon cancer. Although associations between certain genetic aberrations, such as BRAF mutation and microsatellite instability, and the CpG island methylator phenotype (CIMP), have been found, the mechanisms by which these associations are established are still unclear. We studied genome-wide DNA methylation differences between colorectal tumors carrying a BRAF mutation and BRAF wildtype tumors. Results Using differential methylation hybridization on oligonucleotide microarrays representing 32,171 CpG-rich regions, we identified 1,770 regions with differential methylation between colorectal tumor and paired normal colon. Next, we compared the tumor/normal methylation ratios between different groups of patients. Related to CIMP, we identified 749 differentially methylated regions, of which 86% had a higher tumor/normal methylation ratio in the CIMP-positive group. We identified 758 regions with a BRAF mutation-specific methylation change, of which 96% had a higher tumor/normal methylation ratio in the BRAF mutant group. Among the genes affected by BRAF mutation-specific methylation changes, we found enrichment of several cancer-related pathways, including the PI3 kinase and Wnt signaling pathways. To focus on genes that are silenced in a tumor-specific rather than a lineage-specific manner, we used information on the epigenetic silencing mark H3K27me3 in embryonic stem (ES) cells. Among the genes showing BRAF mutation-specific promoter methylation but no H3K27me3 mark in ES cells were forkhead box (FOX) transcription factors associated with the PI3 kinase pathway, as well as MLH1 and SMO. Repression of FOXD3 gene expression in tumors could be related to its promoter hypermethylation. Conclusions We identified new BRAF mutation-specific methylation changes in colorectal cancer. Epigenetic downregulation of these targets may contribute to mutationally active BRAF-driven tumorigenesis, explaining its association with aberrant DNA methylation.
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Affiliation(s)
- Eddy H van Roon
- Center for Human and Clinical Genetics, Leiden University Medical Center, Leiden, The Netherlands.
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Mao M, Tian F, Mariadason JM, Tsao CC, Lemos R, Dayyani F, Gopal YNV, Jiang ZQ, Wistuba II, Tang XM, Bornman WG, Bollag G, Mills GB, Powis G, Desai J, Gallick GE, Davies MA, Kopetz S. Resistance to BRAF inhibition in BRAF-mutant colon cancer can be overcome with PI3K inhibition or demethylating agents. Clin Cancer Res 2012; 19:657-67. [PMID: 23251002 DOI: 10.1158/1078-0432.ccr-11-1446] [Citation(s) in RCA: 227] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
PURPOSE Vemurafenib, a selective inhibitor of BRAF(V600), has shown significant activity in BRAF(V600) melanoma but not in less than 10% of metastatic BRAF(V600) colorectal cancers (CRC), suggesting that studies of the unique hypermethylated phenotype and concurrent oncogenic activation of BRAF(mut) CRC may provide combinatorial strategies. EXPERIMENTAL DESIGN We conducted comparative proteomic analysis of BRAF(V600E) melanoma and CRC cell lines, followed by correlation of phosphoinositide 3-kinase (PI3K) pathway activation and sensitivity to the vemurafenib analogue PLX4720. Pharmacologic inhibitors and siRNA were used in combination with PLX4720 to inhibit PI3K and methyltransferase in cell lines and murine models. RESULTS Compared with melanoma, CRC lines show higher levels of PI3K/AKT pathway activation. CRC cell lines with mutations in PTEN or PIK3CA were less sensitive to growth inhibition by PLX4720 (P = 0.03), and knockdown of PTEN expression in sensitive CRC cells reduced growth inhibition by the drug. Combined treatment of PLX4720 with PI3K inhibitors caused synergistic growth inhibition in BRAF-mutant CRC cells with both primary and secondary resistance. In addition, methyltransferase inhibition was synergistic with PLX4720 and decreased AKT activation. In vivo, PLX4720 combined with either inhibitors of AKT or methyltransferase showed greater tumor growth inhibition than PLX4720 alone. Clones with acquired resistance to PLX4720 in vitro showed PI3K/AKT activation with EGF receptor (EGFR) or KRAS amplification. CONCLUSIONS We show that activation of the PI3K/AKT pathway is a mechanism of both innate and acquired resistance to BRAF inhibitors in BRAF(V600E) CRC and suggest combinatorial approaches to improve outcomes in this poor prognosis subset of patients.
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Affiliation(s)
- Muling Mao
- Department of Gastrointestinal Medical Oncology, The University of Texas MD Anderson Cancer Center, and Graduate School of Biomedical Sciences, University of Texas, Houston, TX 77030, USA
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Dimberg J, Hong TT, Skarstedt M, Löfgren S, Zar N, Matussek A. Analysis of APC and IGFBP7 promoter gene methylation in Swedish and Vietnamese colorectal cancer patients. Oncol Lett 2012; 5:25-30. [PMID: 23255887 DOI: 10.3892/ol.2012.967] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2012] [Accepted: 07/31/2012] [Indexed: 01/05/2023] Open
Abstract
The tumour suppressor gene adenomatous polyposis coli (APC) is a key component that drives colorectal carcinogenesis. The reported DNA methylation in the promoter of APC varies greatly among studies of colorectal cancer (CRC) in different populations. Insulin-like growth factor binding protein 7 (IGFBP7), also known as IGFBP-related protein 1 (IGFBP-rP1), is expressed in various tissue types, including the lung, brain, prostate and gastrointestinal tract, and has been suggested to play a tumour suppressor role against colorectal carcinogenesis. Studies have indicated that IGFBP7 is inactivated by DNA methylation in human colon, lung and breast cancer. In the present study, we used the methylation-specific polymerase chain reaction to study the methylation status of the APC and IGFBP7 gene promoters in cancerous and paired normal tissue to evaluate its impact on clinical factors and association with ethnicity, represented by Swedish and Vietnamese CRC patients. We also investigated the distribution of CpG islands and the CpG dinucleotide density of each CpG island in the regions which were the subject of our investigation. Overall, normal tissue from Swedish patients exhibited a significantly higher frequency of IGFBP7 gene methylation in comparison with that of Vietnamese patients. Moreover, a significantly higher number of cancer tissues from Vietnamese individuals showed higher levels of methylation versus the paired normal tissue compared with that of Swedish patients. When we studied the methylation in cancer compared with the matched normal tissue in individuals, we found that a significantly higher number of Vietnamese patients had a higher degree of IGFBP7 gene methylation in cancer versus matched normal tissue in comparison with Swedish patients. Taken together, our results suggest that the methylation of the APC and IGFBP7 gene promoter region in cancerous tissue, in combination with the predominance of methylation in normal tissue, may serve as a prognostic factor in CRC patients.
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Affiliation(s)
- Jan Dimberg
- Department of Natural Science and Biomedicine, University College of Health Sciences, Jönköping, Sweden
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IGFBP7
Promoter Methylation and Gene Expression Analysis in Prostate Cancer. J Urol 2012; 188:1354-60. [DOI: 10.1016/j.juro.2012.06.002] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2012] [Indexed: 11/18/2022]
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Externalization of saw-tooth architecture in small serrated polyps implies the presence of methylation of IGFBP7. Dig Dis Sci 2012; 57:1261-70. [PMID: 22173745 DOI: 10.1007/s10620-011-2008-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2011] [Accepted: 11/29/2011] [Indexed: 12/20/2022]
Abstract
INTRODUCTION Serrated polyps have been considered to be precursors of colorectal cancer with microsatellite instability. However, the biological and/or morphological changes which occur during the course of serrated polyp to cancer remain to be elucidated. METHODS Twenty-eight colorectal serrated polyps including five mixed polyps (MP) from 20 patients were observed by chromoendoscopy with magnification, and subsequently resected endoscopically. The presence of mutations in two genes (K-ras and BRAF) and the methylation status of six genes (MLH1-A, MLH1-C, ESR1, P16, SOCS1, and IGFBP7) were examined. RESULTS The 28 polyps included 32 histological serrated lesions (22 sessile serrated adenomas [SSA], six hyperplastic polyps [HP], and four traditional serrated adenoma [TSA]-like lesions). BRAF mutation was frequently observed in SSAs (19/22), while K-ras mutation was dominant in HPs (5/6). The externalization of saw-tooth architecture in serrated polyps was endoscopically observed more frequently in those with high levels of IGFBP7 methylation (P = 0.03). Moreover, the endoscopic finding was observed in five of six small serrated lesions (<10 mm) which contained both BRAF mutation and high levels of IGFBP7 methylation. TSA-like lesions in small MPs demonstrated the endoscopic finding with no or little MLH1 methylation, while the counterparts in the mixed polyps had high levels of MLH1 methylation with relatively low levels of IGFBP7 methylation. CONCLUSIONS Our data suggests two distinct pathways may be involved in the early stages of the serrated pathway: one where MLH1 is primarily methylated, and a second where methylated IGFBP7 is associated with an externalization of saw-tooth architecture.
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Benatar T, Yang W, Amemiya Y, Evdokimova V, Kahn H, Holloway C, Seth A. IGFBP7 reduces breast tumor growth by induction of senescence and apoptosis pathways. Breast Cancer Res Treat 2011; 133:563-73. [PMID: 21997538 DOI: 10.1007/s10549-011-1816-4] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2011] [Accepted: 09/30/2011] [Indexed: 01/14/2023]
Abstract
Insulin-like growth factor binding protein 7 (IGFBP7) has been shown to be a tumor suppressor in a variety of cancers. We previously have shown that IGFBP7 expression is inversely correlated with disease progression and poor outcome in breast cancer. Overexpression of IGFBP7 in MDA-MB-468, a triple-negative breast cancer (TNBC) cell line, resulted in inhibition of growth and migration. Xenografted tumors bearing ectopic IGFBP7 expression were significantly growth-impaired compared to IGFBP7-negative controls, which suggested that IGFBP7 treatment could inhibit breast cancer cell growth. To confirm this notion, 14 human patient primary breast tumors were analyzed by qRTPCR for IGFBP7 expression. The TNBC tumors expressed the lowest levels of IGFBP7 expression, which also correlated with higher tumorigenicity in mice. Furthermore, when breast cancer cell lines were treated with IGFBP7, only the TNBC cell lines were growth inhibited. Treatment of NOD/SCID mice harboring xenografts of TNBC cells with IGFBP7 systemically every 3-4 days inhibited tumorigenesis, with associated anti-angiogenic effects, together with increased apoptosis. Upon examining the mechanism of IGFBP7-mediated growth inhibition in TNBC cells, we found that cells not only were arrested in G1 phase of the cell cycle but also underwent senescence as a result of treatment with IGFBP7. Interestingly, IGFBP7 treatment was also associated with strong activation of the stress-associated p38 MAPK pathway, together with upregulation of p53 and the cyclin-dependent protein kinase (CDK) inhibitor, p21(cip1). Prolonged treatment of cells with IGFBP7 resulted in increased cell death, marked by an increase in apoptotic cells and associated cleaved PARP. This is the first study showing that exogenous IGFBP7 inhibits TNBC cell growth both in vitro and in vivo. Taken together, these results suggest IGFBP7 treatment might have therapeutic potential for TNBC.
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Affiliation(s)
- Tania Benatar
- Division of Molecular and Cellular Biology, Sunnybrook Research Institute, Toronto, ON, Canada
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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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Tomimaru Y, Eguchi H, Wada H, Kobayashi S, Marubashi S, Tanemura M, Umeshita K, Kim T, Wakasa K, Doki Y, Mori M, Nagano H. IGFBP7 downregulation is associated with tumor progression and clinical outcome in hepatocellular carcinoma. Int J Cancer 2011; 130:319-27. [PMID: 21328580 DOI: 10.1002/ijc.25994] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2010] [Accepted: 02/02/2011] [Indexed: 01/08/2023]
Abstract
Insulin-like growth factor-binding protein 7 (IGFBP7) functions in several cellular processes including proliferation, senescence and apoptosis. This study analyzed IGFBP7 function in hepatocellular carcinoma (HCC) cells by gene manipulation and investigated the prognostic significance of IGFBP7 expression in clinical HCC samples. In this study, we investigated changes in malignant potential such as cell growth and invasiveness in an HCC cell line, PLC/PRF/5, after transfection with shRNA against IGFBP7. The extent of apoptosis and cell cycle progression were examined after the transfection. The correlation between immunohistochemically determined IGFBP7 expression and long-term postoperative prognosis after curative resection was also investigated in clinical HCC specimens obtained from 104 patients. PLC/PRF/5 cells transfected with shRNA against IGFBP7 showed significantly more rapid growth and stronger invasiveness than control cells. Annexin V assays showed that the IGFBP7-depleted cells were significantly more resistant to apoptosis than the control cells, and showed decreased expression of cleaved caspase-3 and PARP. Cell cycle progression was more rapid in the IGFBP7-suppressed cells. In clinical HCC specimens, IGFBP7 expression was judged as positive in 67 patients (64.4%) and negative in the remaining 37 patients (35.6%). The IGFBP7 downregulation correlated significantly with poor postoperative prognosis, and IGFBP7 status was identified as an independent significant prognostic factor. Our results indicated that IGFBP7 expression correlated significantly with the malignant potential in HCC cells, suggesting that the expression could be a useful prognostic marker for HCC.
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Affiliation(s)
- Yoshito Tomimaru
- Department of Surgery, Graduate School of Medicine, Osaka University, Osaka, Japan
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Methylation status of T-lymphoma invasion and metastasis 1 promoter and its overexpression in colorectal cancer. Hum Pathol 2011; 42:541-51. [DOI: 10.1016/j.humpath.2010.08.013] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2010] [Revised: 07/24/2010] [Accepted: 08/25/2010] [Indexed: 12/31/2022]
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Sun S, Chen Z, Yan PS, Huang YW, Huang THM, Lin S. Identifying hypermethylated CpG islands using a quantile regression model. BMC Bioinformatics 2011; 12:54. [PMID: 21324121 PMCID: PMC3051900 DOI: 10.1186/1471-2105-12-54] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2010] [Accepted: 02/15/2011] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND DNA methylation has been shown to play an important role in the silencing of tumor suppressor genes in various tumor types. In order to have a system-wide understanding of the methylation changes that occur in tumors, we have developed a differential methylation hybridization (DMH) protocol that can simultaneously assay the methylation status of all known CpG islands (CGIs) using microarray technologies. A large percentage of signals obtained from microarrays can be attributed to various measurable and unmeasurable confounding factors unrelated to the biological question at hand. In order to correct the bias due to noise, we first implemented a quantile regression model, with a quantile level equal to 75%, to identify hypermethylated CGIs in an earlier work. As a proof of concept, we applied this model to methylation microarray data generated from breast cancer cell lines. However, we were unsure whether 75% was the best quantile level for identifying hypermethylated CGIs. In this paper, we attempt to determine which quantile level should be used to identify hypermethylated CGIs and their associated genes. RESULTS We introduce three statistical measurements to compare the performance of the proposed quantile regression model at different quantile levels (95%, 90%, 85%, 80%, 75%, 70%, 65%, 60%), using known methylated genes and unmethylated housekeeping genes reported in breast cancer cell lines and ovarian cancer patients. Our results show that the quantile levels ranging from 80% to 90% are better at identifying known methylated and unmethylated genes. CONCLUSIONS In this paper, we propose to use a quantile regression model to identify hypermethylated CGIs by incorporating probe effects to account for noise due to unmeasurable factors. Our model can efficiently identify hypermethylated CGIs in both breast and ovarian cancer data.
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Affiliation(s)
- Shuying Sun
- Case Comprehensive Cancer Center, Case Western Reserve University, Cleveland, Ohio, USA.
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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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Wang XM, Greiner TC, Bibikova M, Pike BL, Siegmund KD, Sinha UK, Müschen M, Jaeger EB, Weisenburger DD, Chan WC, Shibata D, Fan JB, Hacia JG. Identification and functional relevance of de novo DNA methylation in cancerous B-cell populations. J Cell Biochem 2010; 109:818-27. [PMID: 20069569 DOI: 10.1002/jcb.22461] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Epigenetic remodeling is a hallmark of cancer, with the frequent acquisition of de novo DNA methylation in CpG islands. However, the functional relevance of de novo DNA methylation in cancer is less well defined. To begin to address this issue in B-cells, we used BeadArray assays to survey the methylation status of over 1,500 cancer-related CpG loci in two molecular subtypes of diffuse large B-cell lymphoma (ABC-DLBCL and GCB-DLBCL) and cognate normal B-cell populations. We identified 81 loci that showed frequent de novo DNA methylation in GCB-DLBCL and 67 loci that showed frequent de novo DNA methylation in ABC-DLBCL. These de novo methylated CpG loci included reported targets of polycomb repressive complexes (PRC) in stem cells. All candidate loci in GCB-DLBCL are proximal to genes that are poorly expressed or silent in purified normal germinal center (GC) B-cells. This is consistent with the hypothesis that de novo DNA methylation in cancer is more frequently involved in the maintenance rather than the initiation of gene silencing (de novo repression). This suggests that epigenetic switching occurs during tumorigenesis with de novo DNA methylation locking in gene silencing normally mediated by transcriptional repressors. Furthermore, we propose that similar to de novo genetic mutations, the majority of de novo DNA methylation events observed in tumors are passengers not causally involved in tumorigenesis.
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Affiliation(s)
- Xiao-Ming Wang
- Department of Biochemistry and Molecular Biology, University of Southern California, Los Angeles, California 90089, USA
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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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Song EY, Shurin MR, Tourkova IL, Gutkin DW, Shurin GV. Epigenetic mechanisms of promigratory chemokine CXCL14 regulation in human prostate cancer cells. Cancer Res 2010; 70:4394-401. [PMID: 20460540 DOI: 10.1158/0008-5472.can-10-0427] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Chemokines play the key role in initiating immune responses by regulating the attraction and homing of immune cells to the lymphoid and nonlymphoid tissues. CXCL14 is a chemokine that in tumors may act as chemoattractant for monocytes and dendritic cells (DC), which may modulate antitumor immune responses in certain cancers. In this study, we investigated the mechanisms of loss of CXCL14 in prostate cancer cells. Cell treatment with the demethylating agent 5-aza-2-deoxycytidine resulted in the recovery of CXCL14 mRNA and protein expression. Hypermethylated CpG island sequences encompassing the CXCL14 gene promoter were identified. The restoration of CXCL14 by 5-aza-2-deoxycytidine treatment had functional impact, based on the DC chemoattractant activity of conditioned medium from drug-treated cells. Conversely, CXCL14 removal from conditioned media by affinity chromatography abolished its chemotactic properties, confirming that functionally active CXCL14 was generated in prostate cancer cells by relieving its transcriptional silencing with 5-aza-2-deoxycytidine. Our findings offer the first direct evidence for epigenetic regulation of chemokine expression in tumor cells.
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Affiliation(s)
- Eun Young Song
- Seoul National University College of Medicine, Seoul, South Korea
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Abstract
Insulin-like growth factor-binding protein 7 (IGFBP7) is a secreted protein involved in several cellular processes, including proliferation, senescence and apoptosis. Loss of IGFBP7 expression is a critical step in the development of human tumors, including melanoma and colon cancer. By microarray gene expression studies, we have detected downregulation of IGFBP7 gene expression in follicular and papillary thyroid tumors in comparison with normal thyroid tissue. Evaluation of publicly available PTC microarray gene expression data sets confirmed, in a consistent fraction of tumors, the downregulation of IGFBP7 transcript levels. The functional consequence of IGFBP7 downregulation was addressed in the PTC-derived NIM1 cell line in which IGFBP7 expression is repressed by promoter hypermethylation. Exposure to soluble IGFBP7 protein or restoration of IGFBP7 expression by complementary DNA transfection reduced growth rate, migration, anchorage-independent growth and tumorigenicity of NIM1 cells. We show that the effects of IGFBP7 are related to apoptosis. Our data suggest that loss of IGFBP7 expression has a functional role in thyroid carcinogenesis, and it may represent a possible basis for therapeutic strategies.
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Ruan W, Lai M. Insulin-like growth factor binding protein: a possible marker for the metabolic syndrome? Acta Diabetol 2010; 47:5-14. [PMID: 19771387 DOI: 10.1007/s00592-009-0142-3] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2009] [Accepted: 09/03/2009] [Indexed: 11/27/2022]
Abstract
Insulin-like growth factor (IGF) binding proteins (IGFBPs) moved on to contain both IGF high- and low-affinity binders, exerting mitogenic and metabolic actions through its complex interplay between IGF/insulin and its IGF/insulin-independent manner. Progress on the metabolic-related function of IGFBPs has been rapid in recent years. A wealth of studies in 3T3-L1 adipocytes and the transgenic mice models demonstrated that IGFBPs played important roles in the pathogenesis of obesity and insulin resistance. Studies conducted in humans demonstrated the close relation between IGFBPs and the components of the metabolic syndrome. Abnormal expression of IGFBP was detected in various states of the metabolic disorders, suggesting that it could be used as a convenient and sensitive marker of insulin resistance, identification of insulin-resistant individuals at high cardiovascular risk, and may be an earlier marker of the metabolic syndrome. These exciting findings bring us new insight into the elucidation of the metabolic syndrome, which may have important clinical implications.
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Affiliation(s)
- Wenjing Ruan
- Department of Pathology, School of Medicine, Zhejiang University, 388 Yuhangtang Road, Hangzhou, 310058, Zhejiang, China
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Insulin-Like Growth Factor-Binding Protein 7 Regulates Keratinocyte Proliferation, Differentiation and Apoptosis. J Invest Dermatol 2010; 130:378-87. [DOI: 10.1038/jid.2009.265] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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Hinoue T, Weisenberger DJ, Pan F, Campan M, Kim M, Young J, Whitehall VL, Leggett BA, Laird PW. Analysis of the association between CIMP and BRAF in colorectal cancer by DNA methylation profiling. PLoS One 2009; 4:e8357. [PMID: 20027224 PMCID: PMC2791229 DOI: 10.1371/journal.pone.0008357] [Citation(s) in RCA: 121] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2009] [Accepted: 11/20/2009] [Indexed: 12/15/2022] Open
Abstract
A CpG island methylator phenotype (CIMP) is displayed by a distinct subset of colorectal cancers with a high frequency of DNA hypermethylation in a specific group of CpG islands. Recent studies have shown that an activating mutation of BRAF (BRAFV600E) is tightly associated with CIMP, raising the question of whether BRAFV600E plays a causal role in the development of CIMP or whether CIMP provides a favorable environment for the acquisition of BRAFV600E. We employed Illumina GoldenGate DNA methylation technology, which interrogates 1,505 CpG sites in 807 different genes, to further study this association. We first examined whether expression of BRAFV600E causes DNA hypermethylation by stably expressing BRAFV600E in the CIMP-negative, BRAF wild-type COLO 320DM colorectal cancer cell line. We determined 100 CIMP-associated CpG sites and examined changes in DNA methylation in eight stably transfected clones over multiple passages. We found that BRAFV600E is not sufficient to induce CIMP in our system. Secondly, considering the alternative possibility, we identified genes whose DNA hypermethylation was closely linked to BRAFV600E and CIMP in 235 primary colorectal tumors. Interestingly, genes that showed the most significant link include those that mediate various signaling pathways implicated in colorectal tumorigenesis, such as BMP3 and BMP6 (BMP signaling), EPHA3, KIT, and FLT1 (receptor tyrosine kinases) and SMO (Hedgehog signaling). Furthermore, we identified CIMP-dependent DNA hypermethylation of IGFBP7, which has been shown to mediate BRAFV600E-induced cellular senescence and apoptosis. Promoter DNA hypermethylation of IGFBP7 was associated with silencing of the gene. CIMP-specific inactivation of BRAFV600E-induced senescence and apoptosis pathways by IGFBP7 DNA hypermethylation might create a favorable context for the acquisition of BRAFV600E in CIMP+ colorectal cancer. Our data will be useful for future investigations toward understanding CIMP in colorectal cancer and gaining insights into the role of aberrant DNA hypermethylation in colorectal tumorigenesis.
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Affiliation(s)
- Toshinori Hinoue
- USC Epigenome Center, Keck School of Medicine, University of Southern California, Los Angeles, California, United States of America
- Department of Surgery and Department of Biochemistry and Molecular Biology, USC/Norris Comprehensive Cancer Center, Keck School of Medicine, University of Southern California, Los Angeles, California, United States of America
| | - Daniel J. Weisenberger
- USC Epigenome Center, Keck School of Medicine, University of Southern California, Los Angeles, California, United States of America
| | - Fei Pan
- USC Epigenome Center, Keck School of Medicine, University of Southern California, Los Angeles, California, United States of America
| | - Mihaela Campan
- Department of Surgery and Department of Biochemistry and Molecular Biology, USC/Norris Comprehensive Cancer Center, Keck School of Medicine, University of Southern California, Los Angeles, California, United States of America
| | - Myungjin Kim
- Department of Surgery and Department of Biochemistry and Molecular Biology, USC/Norris Comprehensive Cancer Center, Keck School of Medicine, University of Southern California, Los Angeles, California, United States of America
| | - Joanne Young
- Familial Cancer Laboratory, Queensland Institute of Medical Research, Herston, Queensland, Australia
- University of Queensland School of Medicine, Herston, Queensland, Australia
| | - Vicki L. Whitehall
- Conjoint Gastroenterology Laboratory, Clinical Research Centre, Royal Brisbane and Women's Hospital Research Foundation, Herston, Queensland, Australia
| | - Barbara A. Leggett
- Conjoint Gastroenterology Laboratory, Clinical Research Centre, Royal Brisbane and Women's Hospital Research Foundation, Herston, Queensland, Australia
| | - Peter W. Laird
- USC Epigenome Center, Keck School of Medicine, University of Southern California, Los Angeles, California, United States of America
- Department of Surgery and Department of Biochemistry and Molecular Biology, USC/Norris Comprehensive Cancer Center, Keck School of Medicine, University of Southern California, Los Angeles, California, United States of America
- * E-mail:
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Fujishiro H, Okugaki S, Yasumitsu S, Enomoto S, Himeno S. Involvement of DNA hypermethylation in down-regulation of the zinc transporter ZIP8 in cadmium-resistant metallothionein-null cells. Toxicol Appl Pharmacol 2009; 241:195-201. [PMID: 19699220 DOI: 10.1016/j.taap.2009.08.015] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2009] [Revised: 07/31/2009] [Accepted: 08/13/2009] [Indexed: 11/29/2022]
Abstract
The Zrt/Irt-related protein 8 (ZIP8) encoded by slc39a8 is now emerging as an important zinc transporter involved in cellular cadmium incorporation. We have previously shown that mRNA and protein levels of ZIP8 were decreased in cadmium-resistant metallothionein-null (A7) cells, leading to a decrease in cadmium accumulation. However, the mechanism by which ZIP8 expression is suppressed in these cells remains to be elucidated. In the present study, we investigated the possibility that epigenetic silencing of the slc39a8 gene by DNA hypermethylation is involved in the down-regulation of ZIP8 expression. A7 cells showed a higher mRNA level of DNA methyltransferase 3b than parental cells. Hypermethylation of the CpG island of the slc39a8 gene was detected in A7 cells. Treatment of A7 cells with 5-aza-deoxycytidine, an inhibitor of DNA methyltransferase, caused demethylation of the CpG island of the slc39a8 gene and enhancement of mRNA and protein levels of ZIP8. In response to the recovery of ZIP8 expression, A7 cells treated with 5-aza-deoxycytidine showed an increase in cadmium accumulation and consequently an increase in sensitivity to cadmium. These results suggest that epigenetic silencing of the slc39a8 gene by DNA hypermethylation plays an important role in the down-regulation of ZIP8 in cadmium-resistant metallothionein-null cells.
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Affiliation(s)
- Hitomi Fujishiro
- Laboratory of Molecular Nutrition and Toxicology, Faculty of Pharmaceutical Sciences, Tokushima Bunri University, Yamashiro-cho, Tokushima 770-8514, Japan
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Suzuki H, Igarashi S, Nojima M, Maruyama R, Yamamoto E, Kai M, Akashi H, Watanabe Y, Yamamoto H, Sasaki Y, Itoh F, Imai K, Sugai T, Shen L, Issa JPJ, Shinomura Y, Tokino T, Toyota M. IGFBP7 is a p53-responsive gene specifically silenced in colorectal cancer with CpG island methylator phenotype. Carcinogenesis 2009; 31:342-9. [PMID: 19638426 DOI: 10.1093/carcin/bgp179] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
A subset of colorectal cancers (CRCs) show simultaneous methylation of multiple genes; these tumors have the CpG island methylator phenotype (CIMP). CRCs with CIMP show a specific pattern of genetic alterations, including a high frequency of BRAF mutations and a low frequency of p53 mutations. We therefore hypothesized that genes inactivated by DNA methylation are involved in the BRAF- and p53-signaling pathways. Among those, we examined the epigenetic inactivation of insulin-like growth factor-binding protein 7 (IGFBP7) expression in CRCs. We found that in CRC cell lines, the silencing of IGFBP7 expression was correlated with high levels of DNA methylation and low levels of histone H3K4 methylation. Luciferase and chromatin immunoprecipitation assays in unmethylated cells revealed that p53 induces expression of IGFBP7 upon binding to a p53 response element within intron 1 of the gene. Treating methylated CRC cell lines with 5-aza-2'-deoxycytidine restored p53-induced IGFBP7 expression. Levels of IGFBP7 methylation were also significantly higher in primary CRC specimens than in normal colonic tissue (P < 0.001). Methylation of IGFBP7 was correlated with BRAF mutations, an absence of p53 mutations and the presence of CIMP. Thus, epigenetic inactivation of IGFBP7 appears to play a key role in tumorigenesis of CRCs with CIMP by enabling escape from p53-induced senescence.
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Affiliation(s)
- Hiromu Suzuki
- First Department of Internal Medicine, Sapporo Medical University, South 1,West 17, Chuo-ku, Sapporo 060-8556, Japan
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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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Honegger B, Galic M, Köhler K, Wittwer F, Brogiolo W, Hafen E, Stocker H. Imp-L2, a putative homolog of vertebrate IGF-binding protein 7, counteracts insulin signaling in Drosophila and is essential for starvation resistance. J Biol 2008; 7:10. [PMID: 18412985 PMCID: PMC2323038 DOI: 10.1186/jbiol72] [Citation(s) in RCA: 170] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2007] [Revised: 02/15/2008] [Accepted: 03/13/2008] [Indexed: 12/01/2022] Open
Abstract
Background Insulin and insulin-like growth factors (IGFs) signal through a highly conserved pathway and control growth and metabolism in both vertebrates and invertebrates. In mammals, insulin-like growth factor binding proteins (IGFBPs) bind IGFs with high affinity and modulate their mitogenic, anti-apoptotic and metabolic actions, but no functional homologs have been identified in invertebrates so far. Results Here, we show that the secreted Imaginal morphogenesis protein-Late 2 (Imp-L2) binds Drosophila insulin-like peptide 2 (Dilp2) and inhibits growth non-autonomously. Whereas over-expressing Imp-L2 strongly reduces size, loss of Imp-L2 function results in an increased body size. Imp-L2 is both necessary and sufficient to compensate Dilp2-induced hyperinsulinemia in vivo. Under starvation conditions, Imp-L2 is essential for proper dampening of insulin signaling and larval survival. Conclusion Imp-L2, the first functionally characterized insulin-binding protein in invertebrates, serves as a nutritionally controlled suppressor of insulin-mediated growth in Drosophila. Given that Imp-L2 and the human tumor suppressor IGFBP-7 show sequence homology in their carboxy-terminal immunoglobulin-like domains, we suggest that their common precursor was an ancestral insulin-binding protein.
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Affiliation(s)
- Basil Honegger
- Zoological Institute, University of Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland.
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Xu J, Lü B, Xu F, Gu H, Fang Y, Huang Q, Lai M. Dynamic down-regulation of Krüppel-like factor 4 in colorectal adenoma-carcinoma sequence. J Cancer Res Clin Oncol 2008; 134:891-8. [PMID: 18264726 DOI: 10.1007/s00432-008-0353-y] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2007] [Accepted: 01/08/2008] [Indexed: 01/06/2023]
Abstract
PURPOSE To explore the clinical significance of Krüppel-like factors 4 (KLF4) expression in colorectal cancer initiation and progression. METHODS We used quantitative real-time PCR to detect KLF4 mRNA expression in 49 colorectal cancer samples with individual-matched normal mucosa and eight concurrent adenomas. We also analysed the immunostaining pattern of KLF4 in additional 129 colorectal cancers and 48 sporadic colorectal adenomas with matched normal mucosa and correlated KLF4 staining with clinicopathological parameters and prognosis. KLF4 expression change was detected in SW480, SW620 and RKO cell lines after treatment of 5-aza-dC (10 microM) or butyrate sodium (4 mM). RESULTS The large clinicopathological survey with combined methods confirmed a dynamic downregulation of KLF4 in individual-matched normal mucosa, adenoma and cancer (P < 0.05). The quantitative analysis of immunostaining pattern showed that KLF4 staining cells were more frequently seen in the upper zones than that in the lower zones of both normal mucosa and adenoma (P < 0.05). Survival analysis implied a trend toward better overall survival in KLF4-positive colorectal cancer patients with lymph node metastasis than that in KLF4-negative cancer with lymph node metastasis. In vitro study found elevated KLF4 mRNA expression in SW620 and RKO cells with 5-aza-dC treatment, implicating the underlying aberrant epigenetic modifications in regulating KLF4 expression at least in a subset of colorectal cancers. CONCLUSIONS KLF4 is associated with terminal differentiation in colorectal epithelium and drastically downregulated in colorectal adenomas and cancers via possible epigenetic modifications. Loss of KLF4 protein expression might contribute to assessing prognosis in colorectal cancer with lymph node metastasis.
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Affiliation(s)
- Jing Xu
- Department of Pathology, School of Medicine, Zhejiang University, Hangzhou, 310058, People's Republic of China
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Fridman AL, Rosati R, Li Q, Tainsky MA. Epigenetic and functional analysis of IGFBP3 and IGFBPrP1 in cellular immortalization. Biochem Biophys Res Commun 2007; 357:785-91. [PMID: 17451653 DOI: 10.1016/j.bbrc.2007.04.019] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2007] [Revised: 04/03/2007] [Accepted: 04/03/2007] [Indexed: 11/29/2022]
Abstract
Carcinogenic transformation of a cell requires bypassing senescence and becoming immortalized. A cellular senescence-like phenotype can be induced in immortal Li-Fraumeni syndrome (LFS) cells by treating them with the DNA methyltransferase inhibitor 5-aza-deoxycytidine. Our microarray-based expression profiling studies of spontaneously immortalized LFS cell lines identified genes that may provide the growth advantage required for the cells to become immortal. Several members of the IGFBP superfamily of genes fit the profile of genes involved in immortalization: silenced during immortalization and reactivated by 5-aza-deoxycytidine. Overexpression of IGFBP3 or IGFBPrP1 in the immortal LFS cell lines suppressed cell growth and inhibited colony formation. Both genes have the expression pattern of an epigenetically regulated gene and contain CpG islands suitable for methylation-dependent silencing. Analysis of how IGFBPs regulate immortalization will lead to a better understanding of this process and may lead to novel methods for the prevention and treatment of cancer.
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Affiliation(s)
- Aviva Levine Fridman
- Program in Molecular Biology and Genetics, Barbara Ann Karmanos Cancer Institute, Wayne State University School of Medicine, 110 East Warren Avenue, Detroit, MI 48201, USA
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