Description :
Cell proliferation is controlled by growth factors that bind to cell surface receptors which connect to signaling molecules. These molecules activate transcription factors which bind to DNA to modulate the production of proteins, resulting in cell division. Dysfunction of any step in this regulatory cascade causes abnormal cell proliferation, an underlying cause of many human pathological conditions, most notably cancer and aging. Defining mechanisms responsible for alterations in cell cycle progression is crucial to understanding many human diseases, most notably cancer.