Molecular profiling of endometrial cancers from African-American and Caucasian women

Objective. It is widely recognized that racial disparity in survival exists between African-American and Caucasian women with endometrial cancer (EC). Differential mutation frequencies in select genes have been postulated to explain these survival differences. The purpose of this study was to test the hypothesis that African-American women with EC have a distinct gene expression profile compared to Caucasian women with EC. Methods. Microarray-based expression profiling using the Affymetrix U133A oligonucleotide array was performed on a series of ECs from African-American (n = 14) and Caucasian (n = 25). The two groups were matched for possible confounding variables including stage, histologic grade, and subtype. A model-based class comparison analysis was performed to generate a list of differentially expressed genes using a P value of < 0.001. Results. The class comparison analysis of genes differentially expressed by tumors from the two groups revealed 16 genes differentially expressed at P < 0.001, which was not statistically significant (P = 0.68). In addition, hierarchical clustering analysis did not segregate these tumors into two distinct groups based on race. Conclusion. These data indicate that there is no discernible difference in global gene expression profiles of ECs from African-American and Caucasian women. Thus, racial disparities in clinical outcomes are unlikely to reflect differences in gene expression and may instead be attributable to other epidemiologic, clinical, or pathologic factors. (c) 2005 Elsevier Inc. All rights reserved.