However, the associations between several previously reported miR-SNPs, including miR-196a2 rs11614913, miR-146a rs2910164, miR-34b/c rs4938723, and miR-423 rs6505162 and the susceptibility of esophageal squamous cell carcinoma (ESCC) remain controversial.
A case-control study in 248 Kazakh patients with ESCC and 300 frequency matched control subjects was carried out to examine the potential association of six miRNA (miR-100 rs1834306, miR-34b/c rs4938723, miR-375 rs6715345, miR-146a rs2910164, miR-423 rs6505162 and miR-373 rs12983273) polymorphisms with risk of ESCC.
Intriguingly, stratified analysis revealed opposite results that pri-miR-34b/c polymorphism contributed to susceptibility to hepatocellular carcinoma while reduced susceptibility to colorectal cancer and esophageal squamous cell cancer in Asians.
These findings indicated that functional polymorphisms hsa-miR-34b/c rs4938723 T>C and hsa-miR-423 rs6505162 C>A might alter individual susceptibility to ESCC.
We conclude that CpG island methylation of miR-34a, miR-34b/c and miR-129-2 are frequent events and important mechanism for their low expression in ESCC.