Differentially expressed genes in tumors of prostate cancer in American patients with European and African origin

Abstract

AimProstate cancer is one of the most common types of cancer observed in older men globally. In United States, the incidence rate is at its increase over the years and it has been noticed through several studies that the risk of disease differs within population and is more associated with the racial origin. The present study aims at determining differentially expressed (DE) genes using microarray in tumor samples of American patients suffering from prostate cancer who are either from African or European origin. MethodsThe study included microarray data on 89 tumors of prostate cancer. Of these, 34 were African–American, 35 were European–American and 20 were benign samples. After preprocessing, moderated t-statistic was used to determine genes that are differentially expressed across the groups. Gene ontology analysis was performed to understand the functional relevance of differentially expressed genes. ResultsThe analyses resulted into 82 significant genes, of which 24 genes were present in 60 of the 100 simulated datasets with a corresponding threshold δ0 value of 0.00003. These genes discriminated two study groups with an average silhouette width of 0.3211. Gene ADI1 had higher expression in European–American samples, while CTNNB1, PSPH and CRYBB2 had higher expression in African–American samples. ConclusionThe GO analysis considering significant genes revealed that terms like immune response, antigen processing showed relatively higher abundance of DE genes. The potential significance of CTNNB1 and ADI1 genes in prostate cancer biology was re-established. However, their expression patterns are different in two study groups, which is an interesting observation from the study.