Risk factors for breast cancer and the prognosis of African American women: estrogen's role.

Archival reports demonstrate that black females are in the minority of reported breast cancer cases, yet are given a significantly poorer prognosis than their white counterparts. Numerous studies have been conducted in an attempt to explain this discrepancy. In the past, socio-economic variables such as economic status and access to adequate health care have been the focus of attention. More recently there has been a shift to understanding the racial differences in genotype, as well as hormones related to tumor growth. In the present report, we explore the effects of increased estrogen levels as a precursor to the detrimental effects of breast cancer in African American women when compared to Caucasian women. Furthermore we will explore the effects of increased estrogen levels on the apoptotic events of p53 and Bcl-2 proteins. We conclude with a discussion regarding the antagonistic behavior of varying isoforms of estrogen receptors, and their relationship to nitric oxide (NO) as a free radical. The main focus of this paper is to address the many carcinogenic pathways that are instigated by estrogen and those which may be linked to obesity. By determining the relative concentration of estrogen and related proteins within black and white populations we hope to better understand the above mentioned disparity.