DNA Repair and Cell Cycle Checkpoints: Causes and Prevention of Cancer
Abdelilah Aboussekhra
Abstract
A broad range of exogenous (Ultraviolet (UV)-light, ionizing radiation (IR), environmental chemicals) and endogenous (oxidative damage, structural instability) factors alter the genetic material of the cell. If not repaired, DNA damage could lead to mutations and consequently to cell transformation (Friedberg et al., 1995). To preserve the integrity of genetic information, and hence block the development of cancers, all living cells have evolved several coordinated responses to cope efficiently with all kinds of DNA damage. Among these responses are the activation of many DNA repair pathways and the arrest of the cell cycle at different points, called checkpoints. These two responses are the most important front-line defenses against genomic instability and cancer (Hartwell, 1992). During the last decade, tremendous efforts were made to understand the molecular mechanisms underlying these cellular defenses against DNA damage, and to translate the newly acquired knowledge into innovative clinical approaches for the detection and treatment of cancer. Here It will be summarized some of the important findings which pointed out the importance of these cellular responses to DNA damage in carcinogenesis.