P-53-Independent Apoptosis of Human Osteosarcoma Cells After Exposure to Oleuropein

Osteosarcoma is one of the most recurrent primary malignant bone tumors. p-53-null MG-63 human osteosarcoma cells were exposed to oleuropein, an olive compound commonly found in the Mediterranean diet. Caspase-3 activity was measured by a colorimetric assay. In addition, the expression of Bax, Bcl-2 and p-53 mRNA was determined by RT-PCR after 24 h of exposure. Both the ratio of Bax/Bcl-2 mRNA expression and caspase-3 activity were increased in the oleuropein-exposed cells compared with those of the unexposed control (P < 0.05). As expected, no p-53 mRNA was detected in the MG63 cells. Although p-53 function failure is frequently observed in osteosarcoma patients, our results show that oleuropein induces p-53-independent apoptosis in MG-63 human osteosarcoma cells.