VEGFR-2 was reported an upstream protein of Gab1 in endothelial cells [23,25,26] and our data showed that VEGFR-2 and Gab1 were positively correlated in hilar cholangiocarcinoma, so we detected whether VEGFR-2 was the upstream protein of Gab1 in hilar cholangiocarcinoma cells. Here, GAB1 is linked to hilar cholangiocarcinoma.