Our data reveal that lncRNA XIST may promote tumor metastasis in CRC possibly through regulating the miR-137-EZH2 axis. lncRNA XIST may serve as a prognostic indicator for CRC progression.
Survival differences were evaluated using Kaplan-Meier analyses. miR-137 CpG island methylation was more frequent in tumorous compared to non-tumorous conditions and higher in CRC than in GC.
By analyzing a large, population-based CRC cohort, we demonstrate the potential clinical significance of miR137 and IGFBP3 hypermethylation as promising diagnostic biomarkers in CRC.
Expression of miR-137 in colorectal cancer cell lines was found inversely correlated with Cdc42 expression. miR-137 could significantly suppress Cdc42 3' UTR luciferase-reporter activity, and this effect was not detectable when the putative 3' UTR target-site was mutated.
Methylation of the miR-137 CpG island was a cancer-specific event and was frequently observed in CRC cell lines (100%), adenomas (82.3%), and CRC (81.4%), but not in N-C (14.4%; P < 0.0001 for CRC) and N-N (4.7%; P < 0.0001 for CRC).
Further, methylation of the hsa-miR-9-1, hsa-miR-129-2 and hsa-miR-137 CpG islands were frequently observed in CRC cell lines and in primary CRC tumors, but not in normal colonic mucosa.