Inverse correlation between promoter methylation and expression suggested miR-129-2 and members of the miR-200 family (miR-200a, miR-200b, and miR-429) as novel tumor suppressors and oncomiRs, respectively, in CC.
We found that miR-200b/c influenced the tumourigenesis of cholangiocarcinoma cells including their tumour-initiating capacity, sphere formation, and drug resistance.
In addition, several miRNAs were shown to influence sensitivity to chemo- or radiotherapy: miRNAs of the Let-7 family induced radiosensitivity in vitro/in vivo, inhibition of miR-21 and miR-200b increased sensitivity to gemcitabine in cholangiocarcinoma cell lines, and restoration of miR-34 in p53-deficient human gastric cancer cells induced chemosensitisation.