title: Genetic variationrs7930in the miR-4273-5p target site is associated with a risk of colorectal cancer.
abstract: OBJECTIVE
  MicroRNAs (miRNAs) are noncoding RNAs that play roles as tumor suppressors or oncogenes by regulating the expression of target genes via binding to seed-match sequences. Polymorphisms in the miRNA-binding site of a target gene can alter miRNA binding and potentially affect the risk of cancer. The objective of this study was to identify single-nucleotide polymorphisms (SNPs) in miRNA-binding sites and assess their involvement in the risk of colorectal cancer (CRC).
  
  
  METHODS
  SNPs in the 3' untranslated regions of genes were selected and assessed for their effects on CRC risk in Korean population using participants in Korean Cancer Prevention Study-II. A detailed study was carried out with the SNPrs7930in the 3' untranslated region of the translocase of outer mitochondrial membrane 20 (TOMM20) gene. A case-control study (1,545 controls and 620 CRC cases) was conducted to analyze the relationship between polymorphism atrs7930and the risk of CRC. An interacting miRNA was predicted using web-based software programs, and its interaction withrs7930in CRC cell lines was investigated by using a luciferase assay.
  
  
  RESULTS
  Individuals carrying thers7930AG genotype (G allele) had a 1.721-fold increased risk for CRC in comparison with those with the AA genotype (A allele). The miRNA miR-4273-5p was found to specifically interact with the A allele ofrs7930and to suppress the expression of the target gene (TOMM20) in CRC cell lines.
  
  
  CONCLUSIONS
  rs7930is an independent genetic risk factor for CRC susceptibility. Our study suggests a mechanism of how this SNP contributes to CRC carcinogenesis.
authors.affiliation: Department of Medical Life Sciences, The Catholic University of Korea, Seoul, South Korea.
authors.forename: Ah-Reum
authors.initials: AR
authors.lastname: Lee
authors.affiliation: Department of Medical Life Sciences, The Catholic University of Korea, Seoul, South Korea.
authors.forename: Jongkeun
authors.initials: J
authors.lastname: Park
authors.affiliation: Department of Epidemiology and Health Promotion, Institute for Health Promotion, Graduate School of Public Health, Yonsei University, Seoul, Republic of Korea.
authors.forename: Keum Ji
authors.initials: KJ
authors.lastname: Jung
authors.affiliation: Department of Epidemiology and Health Promotion, Institute for Health Promotion, Graduate School of Public Health, Yonsei University, Seoul, Republic of Korea.
authors.forename: Sun Ha
authors.initials: SH
authors.lastname: Jee
authors.affiliation: Department of Medical Life Sciences, The Catholic University of Korea, Seoul, South Korea.
authors.forename: Sungjoo
authors.initials: S
authors.lastname: Kim-Yoon
keywords: SNP; colorectal cancer; frequency; miR-4273-5p; rs7930; susceptibility