TET1 and cholangiocarcinoma: miR-191 expression was found to be an independent risk factor for a worse prognosis for human CCA patients.In vivo andin vitro analysis revealed that overexpression of miR-191 was associated with enhanced proliferation, invasion, and migration and reduced ten-eleven translocation 1 (TET1) expression, which induces DNA demethylation and was shown to be a direct target of miR-191.