(A). Immunofluorescence showing that Ola+Ent significantly reduces BRCA1 and Ki-67 expression levels in SKOV-3 cells. DAPI was used as nuclear stain (40X 100 micron scale bar). Quantification of BRCA1 and Ki-67 indicated significant downregulation in cells treated with Ola+Ent (*p < 0.05, **p<0.005 Students T-test). (B) BRCA1 transcript levels showed significant downregulation in all treatment groups, with enhanced downregulation in Ola+Ent (*p < 0.012; **p<0.0036; ***p<0.0005, one-way ANOVA; Sidak’s multiple comparison test) indicating that BRCA1 expression is affected markedly at the mRNA levels compared to protein levels. (C) Western blot analysis of SKOV-3 cells treated with Ola+Ent as described for SRB assay showing increased cleaved PARP expression in olaparib and Ola+Ent treated cells. Quantification showed significant upregulation of cleaved PARP, a marker of cell death (*p< 0.05; **p<0.005, Students T-test). The antibody used was specific for fragments of PARP1. [Con – Control; Ola – Olaparib; Ent – Entinostat].