Okadaic acid induces apoptosis through the PKR, NF-κB and caspase pathway in human osteoblastic osteosarcoma MG63 cells

► OA induced cytotoxicity and apoptosis in MG63 cells at IC50 of 75 nM. ► A functional PKR pathway is required to induce apoptosis in response to OA treatment. ► Blockade of NF-κB by PDTC resulted in down-regulation of apoptosis. ► The caspase-3 and caspase-8 inhibitors blocked apoptosis in MG63 cells.