A good view of this is illustrated on the cover of the December 1996 issue of Scientific American . The subcellular fragments are then ingested by neighboring cells or macrophages. This all happens without any leakage of cell contents into the extra-cellular space or bloodstream. This is important because accidentally leaked cytoplasm would trigger an inflammatory response in the organism. Apoptosis is relatively inconspicuous to the immune system, whereas necrosis results in inflammation in the surrounding environment.
Cancers appear when more cells proliferate than die in a given tissue.
Many human neoplasms have been found to have a mutation in at least one apoptosis gene. Some tumor suppressor genes control cell proliferation, while others are involved in the induction of apoptosis. The oncogene, c- myc , has been shown to induce apoptosis. The production of the tumor suppressor protein p53 has been shown to lead to prompt activation of programmed cell death. Mammals have the bcl-2 gene that codes for membrane protein that prevents or delays apoptosis in neurons and lymphocytes.