Restricting apoptosis for postmitotic cell survival and its relevance to cancer.

The importance of apoptosis in multicellular organisms is signified by the high degree of genetic conservation in the core components of this pathway from C. elegans through mammals. However, as the cells which comprise these organisms have diversified and become more specialized, so have the mechanisms which regulate the apoptotic pathway. The complex regulatory mechanisms by which the apoptotic pathway is refined are perhaps most apparent in differentiated postmitotic cells such as neurons, cardiomyocytes, and skeletal myotubes. The lack of significant regenerative potential in postmitotic cells demands that they must persist long-term, often for the full lifespan of an organism. Recent studies have identified several diverse mechanisms by which postmitotic cells restrict their apoptotic potential. Importantly, these mechanisms may also be coopted by cancer cells in order to evade apoptosis.