.ESSAY ON ANALYSIS OF BCL-2 GENE IN IIREAST CANCER

Abstract

The neoplastic phenotype is a consequence of alternation in genes that regulate cell growth and differentiation (Wyllie et a!., 1995).

Two of the most relevant proteins involved in apoptosis and tumor development are Bcl-2 and P53. It recently has been found that the Bcl-2 protein is expressed in a variety of normal tissues including breast epithelium (Sabourini eta!., 1994).

There is a relationship has been reported between bcl-2 expression and factors of good prognosis such as hormone receptor positivity small tumor size. Low histologic grade and reduced levels of epidermal growth factor receptor (Sierra, et a!., 1995)

An inverse relationshipe between bcl-2 and P53 protein expression has been observed in breast carcinoma suggesting that mutant P53 might down-regulate bcl-2 expression (Silvestrini eta!., 1994, Gee eta!., 1994).

Bcl-2 and Bax apoptosis related proteins are good indicators of prognosis in node negative breast cancer patients and their combined absence suggestive of serious deregulation of the apoptotic process may .,,: contribute to the biologic aggressiveness of the tumors (Kapranos eta!.,

1997).

This protein has been detected in > 50% of breast tumors and its presence has been related to good prognositic factors (Leek et a!., 1994).

Bcl-2 expression in breast epithelium are associated intimately with the levels of steroid hormones during the menstrual cycle (Bargou et a!.,