SPHK2 and cholangiocarcinoma: Therefore, we decided to investigate the following: (1) whether pharmacological inhibition of Sphk2 by ABC294640 inhibits CCA cell growth; (2) whether ABC294640 modulates apoptosis and autophagy in CCA cells; (3) whether induction of autophagy in CCA cells has a pro-survival or pro-death effect; (4) whether ABC294640 has a synergistic effect with sorafenib in CCA cells.