LIF and cholangiocarcinoma: To dissect the intracellular signaling that mediates the protective effect of LIF against drug-induced apoptosis in CCA cells, relative expression levels of pBax (pro-apoptotic protein), and Bcl-2 and Mcl-1 (anti-apoptotic proteins) were studied by WB in LIF pre-treated HuCCT-1 and TFK-1 cells.