A SIMILAR PATTERN OF CHROMOSOMAL ALTERATIONS IN PROSTATE CANCERS FROMAFRICAN-AMERICANS AND CAUCASIAN AMERICANS

A combination of genetic and epigenetic factors may explain the dispro portionate incidence and mortality of prostate cancer among African-Am erican males (AAMs) as compared with Caucasian American males (CAMs), We wished to determine whether primary prostate cancers from AAMs and CAMs harbor different patterns or frequencies of chromosomal alteratio ns. Comparative genomic hybridization (CGH) was performed on clinicall y localized, untreated primary prostate cancers from 16 AAMs and 16 CA Ms, Detailed statistical analysis was used to delineate gains and dele tions with high sensitivity and specificity and to compare the frequen cy and pattern of alterations between the two groups of tumors. The tw o groups of patients had indistinguishable preoperative serum prostate -specific antigen levels, and the two groups of tumors had similar pat hological stages and grades. Chromosomal gains and deletions occurred in regions known to be frequently altered in prostate cancer. Specific ally, the most frequent alterations were deletions of regions on chrom osomes 13q, 5q, 16q, and 8p and gains of regions on 8q and 5q, When tu mors from AAMs and CAMs were compared, the frequencies of alteration ( deletion, gain, or no alteration) were similar across 98.9% of the len gth of the genome. The patterns of alterations of the most frequently altered chromosomes were also similar between tumors from AAMs and CAM s. We concluded that primary prostate cancers from AAMs and CAMs harbo r a similar pattern and frequency of chromosomal alterations. These da ta support the notion that sporadic prostate cancers from AAMs and CAM s develop by similar chromosomal mechanisms. Biological differences, i f present, do not occur on the chromosomal level.