SLCO1B3 and hepatocellular carcinoma: In particular, overexpression of HNF3γ could reduce the drug resistance of HCC by upregulating the expression of OATP1B1 and OATP1B3, which are the two major membrane transport proteins affecting sorafenib absorption, thus sensitizing HCC cells to sorafenib-induced growth repression and apoptosis 25.