title: IGFBP3 promoter methylation in colorectal cancer: relationship with microsatellite instability, CpG island methylator phenotype, and p53.
abstract: Insulin-like growth factor binding protein 3 (IGFBP3), which is induced by wild-type p53, regulates IGF and interacts with the TGF-beta pathway. IGFBP3 promoter methylation may occur in colorectal cancer with or without the CpG island methylator phenotype (CIMP), which is associated with microsatellite instability (MSI) and TGFBR2 mutation. We examined the relationship between IGFBP3 methylation, p53 expression, CIMP and MSI in 902 population-based colorectal cancers. Utilizing real-time PCR (MethyLight), we quantified promoter methylation in IGFBP3 and eight other CIMP-high-specific promoters (CACNA1G, CDKN2A, CRABP1, IGF2, MLH1, NEUROG1, RUNX3, and SOCS1). IGFBP3 methylation was far more frequent in non-MSI-high CIMP-high tumors (85% = 35/41) than in MSI-high CIMP-high (49% = 44/90, P < .0001), MSI-high non-CIMP-high (17% = 6/36, P < .0001), and non-MSI-high non-CIMP-high tumors (22% = 152/680, P < .0001). Among CIMP-high tumors, the inverse relationship between MSI and IGFBP3 methylation persisted in p53-negative tumors (P < .0001), but not in p53-positive tumors. IGFBP3 methylation was associated inversely with TGFBR2 mutation in MSI-high non-CIMP-high tumors (P = .02). In conclusion, IGFBP3 methylation is inversely associated with MSI in CIMP-high colorectal cancers, and this relationship is limited to p53-negative tumors. Our data suggest complex relationship between global genomic/epigenomic phenomena (such as MSI/CIMP), single molecular events (e.g., IGFBP3 methylation, TP53 mutation, and TGFBR2 mutation), and the related pathways.
authors: Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA 02115, USA.
authors: Takako
authors: T
authors: Kawasaki
authors: Katsuhiko
authors: K
authors: Nosho
authors: Mutsuko
authors: M
authors: Ohnishi
authors: Yuko
authors: Y
authors: Suemoto
authors: Gregory J
authors: GJ
authors: Kirkner
authors: Charles S
authors: CS
authors: Fuchs
authors: Shuji
authors: S
authors: Ogino
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics* / Q000473:pathology; D002887:Chromosomes, Human, Pair 18 / Q000235:genetics / Q000648:ultrastructure; D015331:Cohort Studies; D015179:Colorectal Neoplasms / Q000235:genetics* / Q000473:pathology; D018899:CpG Islands / Q000235:genetics*; D019175:DNA Methylation; D004273:DNA, Neoplasm / Q000737:chemistry / Q000235:genetics*; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D016158:Genes, p53; D006801:Humans; D018972:Insulin-Like Growth Factor Binding Protein 3; D018969:Insulin-Like Growth Factor Binding Proteins / Q000235:genetics*; D019656:Loss of Heterozygosity; D008297:Male; D053842:Microsatellite Instability; D009363:Neoplasm Proteins / Q000235:genetics / Q000502:physiology*; D010641:Phenotype; D011401:Promoter Regions, Genetic / Q000235:genetics*; D016159:Tumor Suppressor Protein p53 / Q000172:deficiency / Q000502:physiology*
chemical_list: D004273:DNA, Neoplasm; C515497:IGFBP3 protein, human; D018972:Insulin-Like Growth Factor Binding Protein 3; D018969:Insulin-Like Growth Factor Binding Proteins; D009363:Neoplasm Proteins; D016159:Tumor Suppressor Protein p53