MDK and cholangiocarcinoma: Lastly, DEP Domain Containing 1 (DEPDC), Fucosyltransferase 4 FUT4, Midkine (MDK), Phosphofurin acidic cluster sorting protein 1 (PACS1), Piwi-like protein 4-Homo sapiens 1 (PIWIL4) genes, miR-22, miR-551b, and cg27362525 and cg26597242 CpG have been proposed as potential prognostic markers for cholangiocarcinoma (144) (Table 2).