ACE2 and cholangiocarcinoma: Such correspondence is highlighted as red bars in Fig. 3: ACE2 is highly expressed in the gallbladder, testis, kidney and colon normal tissues (1st, 2nd, 3rd and 4th in rank) and consistently shows significant different expression in cholangiocarcinoma, testis, kidney and colon cancers (i.e. in the corresponding body districts).