Bcl-2 family proteins and cancer.

BCL-2 was the first anti-death gene discovered, a milestone with far reaching implications for tumor biology. Multiple members of the human Bcl-2 family of apoptosis-regulating proteins have been identified, including six antiapoptotic, three structurally similar proapoptotic proteins and several structurally diverse proapoptotic interacting proteins that operate as upstream agonists or antagonists. These proteins, in turn, are regulated through myriad post-translational modifications and interactions with other proteins. Bcl-2-family proteins regulate all major types of cell death, including apoptosis, necrosis and autophagy, thus operating as nodal points at the convergence of multiple pathways with broad relevance to oncology. Experimental therapies targeting Bcl-2-family mRNAs or proteins are currently in clinical testing, raising hopes that a new class of anticancer drugs may soon be available.