For differentiation into ICC-LCs, hUSCs were transfected with lentiviral vectors that encode the stem cell factor (SCF), c-kit, the 5-azacytidine-induced 2 (AZI2) gene, and hyperpolarization-activated cyclic nucleotide gated potassium channel 4 (HCN4) [154]. This evidence concerns the gene HCN4 and intrahepatic cholangiocarcinoma.