الفهرس | Only 14 pages are availabe for public view |
Abstract Breast cancer is the most common cancer and the second most common cause of death in woman . In Egypt, breast carcinoma is the most common malignancy in women. It consists 31.3% of malignancy tumors affecting females.Tumor can arise from alternation in the activity of genes that results in accelerated rates of cell division ,decreased rates of cell death or both. The balance among cell proliferation , cell differentiation and cell death determines the cell number in a population as well as the size or even the stage of a tumor.Apoptosis is highly regulated form of programmed cell death which occurs extensively in tissue homeostasis and morphogenesis, and which is thought also to be involved in cell turnover in various tumors. Two apoptosis related antigens, p53 (tumor suppressor oncogene) and bcl2 (antiapoptotic oncogene), have been suggested to play an important role in tumor progression by affecting the magnitude of tumor cell apoptosis, or by altering the proliferation of tumor cells. Apoptosis is an active process that requires protein synthesis and endonucleolytic digestion of cellular DNA. Several genes seem to be involved in the induction as well as the inhibition of apoptosis, these genes are as important as the oncogenes that exert their effect by accelerating of cell proliferation. Bcl2 was the first isolated oncogene from the breakpoint site of t (14; 18) (q32, q21) found in > 80% of follicular B cell lymphomas. |