Oncogenes, apoptosis and cancer

In multicellular organisms under physiological and certain pathological conditions, cell death occurs by the genetically regulated programme of apoptosis. Apoptosis is morphologically characterised by cell shrinkage and fragmentation, while the biochemical hallmark of apoptosis is the classical internucleosomal DNA fragmentation. A deregulation in the finely tuned death machinery, may tip the balance in favour of cell survival and development of cancer. A number of genes have been implicated in the development and progression of a variety of human cancers. Interestingly in the last few years much evidence has been gathered to also suggest a role for these genes in the regulation of apoptosis. Such genes include myc, p53, bcl-2 and bcr-abl. This article reviews the role of these genes in the regulation of apoptosis and also focuses on how deregulated apoptosis may play a key role in oncogenesis.