In the human hepatoma SK-Hep-1 cell subline with complete mtDNA depletion, bile-acid-induced proapoptotic signalling was reduced, as indicated by decreased expression rates of Bax-α/B cell lymphoma-2 (Bcl-2), Bcl XS/Bcl-2, and Bcl XS/Bcl XL, as well as reduced bile-acid-induced reactive oxygen species (ROS) production (Marin et al., 2013). This evidence concerns the gene BCL2 and hepatocellular carcinoma.