Just as signals regulate cell growth and division, signals control cell death. Cancers can result from cells that do not die when they should.
Robert Weinberg, Ph.D
Whitehead Institute for Biomedic Research
Cancer cells have to learn how to avoid the process of programmed cell death – suicide – otherwiseknown as apoptosis.
A cell may die because it is damaged or old. Once a cell is signaled to die,the cell makes proteases and enzymes that degrade its components. The DNA inthe nucleus is fragmented, the cell membrane shrinks, and, eventually, a neighboringcell engulfs the cellular remains.
In 2000, Douglas Hanahan (shown below) and Robert Weinberg published a paperin Cell, "The Hallmarks of Cancer," which identified some organizingprinciples of cancer cell development.
A fundamental property of multi-cellular organisms is the capability to commitsuicide or undergo apoptosis, which is a form of programmed cell death. And itis evident that this is another check and balance on aberrant tissues, so thatearly on in the development of many cancers one can see prominent induction ofapoptosis, which we imagine to be a form of protection for the organism. Thecells are proliferating apparently and they therefore commit suicide for thecommon good.