Abstract B38: A novel model for characterizing differential microRNA expression in African American prostate cancers

Purpose: The aim of this study was to determine the micro-RNA (miRNA) expression profile of African American and European American prostate cancer cell lines. In addition, experimentally determine the possible functional role of those mi-RNAs determined to be significantly expressed within both groups. Experimental Design: The expression profile was investigated using novel African American and European American prostate cells with pathological stages determined to be normal, benign, metastatic, and primary tumors. The expression pattern was determine by miRNA microarray analysis and validated by Real-Time quantitative Reverse Transcription-PCR (qRT-PCR). Results: We detected 37 known miRNAs in African American androgen-dependent prostate cancer cells compared to those in European American androgen-independent prostate cancer cell lines using microarray analysis. Mir-26a was selected for validation by qRT-PCR, the results showed that African American androgen dependent cell line RC-165N/hTERT, RC-77N/hTERT and RC-77T/hTERT expressed higher levels of mir-26a compared to European American prostate cell lines. All androgen independent prostate cells DU-145, DU-145 WT, and PC-3 cells, show a substantial decrease in mir-26a compared to African American prostate cell lines. In addition, as cells lines increase in aggression in both groups, the expression of mir-26a also increased significantly, indicating that mir-26a could be a possible contributor to metastasis. Conclusion: To date, we are unaware of any studies that compare the miRNA profile in different stages of prostate cancer along with comparison within two ethnic groups, showing the importance of epigenetics in relation to such factors. Furthermore, this experiment suggests that miRNA9s could possibly contribute to the aggressiveness associated in African American patients with prostate cancer.