TP53 and hepatocellular carcinoma: CSE is over-expressed in hepatoma HepG2 and PLC/PRF/5 cells, inhibition of the CSE/H2S axis causes elevated intracellular ROS, upregulated p53/p21 expression, and decreased Bcl-2/Bax ratio, as well as activates JNK/MAPK, which together promote the mitochondrial apoptotic pathway in HCC cells [64].