Using the TCGA database, the miR-29 family were predicted to regulate DNA demethylation by potentially targeting TET1.206 Indeed, miR-29b directly targeted and repressed TET1 to promote the mesendoderm lineage formation207 and the miR-19b/TET1 axis could be utilized in attenuating osteoarthritis progression.208 Downregulation of TET1 also has been reported by miR-494 in hepatocellular carcinoma tumors209 and by miR-191 in intrahepatic cholangiocarcinoma,210 respectively. The gene discussed is TET1; the disease is intrahepatic cholangiocarcinoma.