ABCG2 and ovarian cancer: In order to scrutinize the initiating cell status and identity of iOVCAR-3-OSKM cells, we evaluated the expression levels of several ovarian cancer initiating cell (OCIC) markers that previously reported like CD133 [25], CD177 [26], CD24 [27], CD44 [28], ABCG2 [29], and ALDH1 [30] in cells.