However, the results of subgroup analyses revealed that the upregulation of tissue miR-203 expression was associated with poor OS in colorectal cancer (hazard ratio (HR)=1.81, 95% confidence intervals (CI) 1.31-2.49; P<0.001), pancreatic cancer (HR=1.19, 95% CI 1.09-1.31; P<0.001) and ovarian cancer (HR=1.85, 95% CI 1.45-2.37; P<0.001); but it had opposite association in liver cancer (HR=0.52, 95% CI 0.28-0.97; P=0.040) and esophageal cancer (HR=0.41, 95% CI 0.25-0.66; P<0.001).
The inhibition of proliferation and invasiveness in esophageal cancer cells after treated with 5-Aza-dC or transfected with miR-203a or miR-203b mimics, suggesting the tumor suppressor role of both miRNAs in esophageal cancer.
Our data suggest that altered expression of miR-21, miR-29c, miR-148 and miR-203 are related to neoplastic transformation and progression of the disease and these microRNAs could serve as a potential diagnostic and prognostic biomarkers in esophageal cancer.
Furthermore, we demonstrate that C/EBPβ LIP mediates epithelial growth factor (EGF)-induced EMT and increases migration and invasion of esophageal cancer cells in a manner that is dependent on miR-203 inactivation.
Taken together, our findings suggest that miR-203 may act as novel tumor suppressor in esophageal cancer through down-regulating the expression of Ran and miR-21.