CYCS and cancer: Finally, they enhance p53-mediated apoptosis in cancer cells.76 However, B-cell lymphoma 2 (Bcl-2) in mitochondrial outer membrane promotes cell survival and inhibits the action of pro-apoptotic proteins to regulate apoptosis.77 In addition, B-cell lymphoma-extra-large (Bcl-xL) is a transmembrane molecule in mitochondria, which reduces mitochondrial outer membrane permeability to block the release of cytochrome C and pro-apoptotic proteins.78 Therefore, Bcl-2 family proteins contribute to cell survival by anti-apoptosis.