Figure S1 shows results od cell viability assays, PRKRA expressions and time course experiments. Figure S2 shows results of heatmap for gene expressions and IPA. Figure S3 shows results of cell viability assay, in vivo experiment. Figure S4 shows the results of experiments for PACT-Dicer or PACT- miR 515-3p interaction. Figure S5 shows the results of experiments for miR-515-3p-AXL interaction.
ARTICLE ABSTRACTFor mucinous ovarian cancer (MOC), standard platinum-based therapy is largely ineffective. We sought to identify possible mechanisms of oxaliplatin resistance of MOC and develop strategies to overcome this resistance. A kinome-based siRNA library screen was carried out using human MOC cells to identify novel targets to enhance the efficacy of chemotherapy. In vitro and in vivo validations of antitumor effects were performed using mouse MOC models. Specifically, the role of PRKRA/PACT in oxaliplatin resistance was interrogated. We focused on PRKRA, a known activator of PKR kinase, and its encoded protein PACT because it was one of the five most significantly downregulated genes in the siRNA screen. In orthotopic mouse models of MOC, we observed a significant antitumor effect of PRKRA siRNA plus oxaliplatin. In addition, expression of miR-515-3p was regulated by PACT–Dicer interaction, and miR-515-3p increased the sensitivity of MOC to oxaliplatin. Mechanistically, miR-515-3p regulated chemosensitivity, in part, by targeting AXL. The PRKRA/PACT axis represents an important therapeutic target in MOC to enhance sensitivity to oxaliplatin.