Anti-proliferative effect in epithelial ovarian cancer cells by MEK Inhibitor AZD6244 / 대한산부인과학회지

ABSTRACT

OBJECTIVE: The objectives of this study were to determine the efficacy of AZD6244, a potent, selective MEK inhibitor, in epithelial ovarian cancer (EOC) cells and to determine the enhanced cell death by combined treatment of paclitaxel and AZD6244. METHODS: EOC cells were treated with tenfold dilutions of AZD6244 (0.1 to 10 micrometer) for 24, 48 and 72 hours. Cell viability was determined by the CellTiter 96 AQueous One Solution Cell Proliferation Assay. The apoptotic cascade was assessed by Caspase-Glo assays. ERK activation was evaluated by Western blot analyses. Cytokine profiling was performed from culture supernatants using the Luminex 200 system. RESULTS: In vitro cell viability showed that ovarian cancer cells with high p-ERK activities (A2780, R454, 01-28) exhibited significant growth inhibition. Cells with low p-ERK activities (R182, CP70), however, were resistant to AZD6244. Caspase-3 was not activated during AZD6244-induced growth inhibition. AZD6244 significantly inhibited p-ERK1/2 in both cell types regardless of constitutive levels of p-ERK. Proinflammatory cytokines including IL-6, IL-8, MCP-1 and GM-CSF were significantly decreased. Paclitaxel activated the p-ERK levels in paclitaxel-resistant R182 cells with low basal p-ERK level. MEK inhibition by AZD6244 enhanced paclitaxel-induced apoptosis significantly in R182 cells. CONCLUSION: These results demonstrate that AZD6244 has a potent growth inhibitory effect in ovarian cancer cells with high p-ERK activities. In addition, targeted inhibition of the extracellular signal-regulated kinase pathway with AZD6244 can enhance the anti-tumor efficacy of the cytotoxic paclitaxel.