BRCA1 and ovarian cancer: Nevertheless, Various circRNAs (such as circ-ITCH, circPLEKHM3, circRNA_100395, circLARP4) have been found to inhibit the proliferation of ovarian cancer cells by acting as miRNA sponges.[16,17,20,22] CircPLEKHM3 suppresses the proliferation and migration of ovarian cancer cells by sponging miR-9 to regulate BRCA1, DNAJB6, and KLF4.