Lack of association between an insertion/deletion polymorphism in IL1A and risk of colorectal cancer.

Previous study has shown that miR-122, miR-378, and their target gene IL1A may play crucial roles in the tumorigenesis of colorectal cancer (CRC). An insertion/deletion polymorphism (rs3783553 TTCA/-) in the 3' untranslated region of IL1A has been identified as a contributing factor to the risk of developing several cancers. The aim of this study was to evaluate the effect of IL1A rs3783553 on CRC risk. CRC patients (N = 339) and healthy control subjects (N = 313) were enrolled and genomic DNA was extracted from peripheral venous blood. The IL1A rs3783553 polymorphism was genotyped using a polymerase chain reaction assay. No significant differences in IL1A rs3783553 genotype frequencies were found between CRC cases and controls in an analysis of the overall data [ins/ del vs del/del: adjusted odds ratio (OR) = 0.96, 95% confidence interval (CI) = 0.69-1.34; ins/ins vs del/del: adjusted OR = 0.71, 95%CI = 0.43- 1.16; ins vs del: adjusted OR = 0.86, 95%CI = 0.69-1.09], nor when data were stratified according to clinical parameters. These findings indicate that the IL1A rs3783553 polymorphism does not constitute a risk factor for the development of CRC.