Abstract B052: Identification of differentially expressed micro-RNAs in African American women with Quadruple Negative Breast Cancer

Purpose: Recently, we have demonstrated that triple-negative breast tumors (TNBC) that lack the expression of androgen receptor are quadruple-negative tumors (QNBC) and have increased aggressiveness. Additionally, we determined that this is due to a unique gene signature in the QNBC subtype. However, whether this gene signature is associated with a unique miRNA expression and differential in African American (AA) women compared to Caucasian (CA) women has not been determined. Therefore, the purpose of this study is to determine the miRNA expression in presence or absence of androgen receptor in both African American and Caucasian QNBC patients. Methods: miRNA level 3 sequencing files were originally downloaded on June 1, 2016 from TCGA for 925 breast cancer patients. The miRNA sequence files (RPKM) and gene expression files (FPKM UQ) were obtained for normal and tumor samples for these patients. Median value of AR FPKM UQ was used as cut-off and divided patient group as AR(+ve/-ve). Results: Out of 925 patients, 101 patients have TNBC. Among TNBC patients, 107 are QNBC and 8 patients are AR-positive TNBC. Reads per million for 1046 miRNAs were considered for this study. 40 miRNAs showed differential expression in QNBC. (p-value