Polydatin enhances the chemosensitivity of osteosarcoma cells to paclitaxel

Despite improvements in the prognosis of osteosarcoma patients, chemotherapy fails in a considerable number of cases due to drug resistance. The development of novel agents may enhance chemosensitivity. This study explored the anticancer function of polydatin and its ability—in combination with paclitaxel—to overcome drug resistance in human osteosarcoma U-2OS and MG-63 cell lines. A cell proliferation assay (celll counting kit-8), a cell-cycle assay, an apoptosis assay (annexin V-fluorescein isothiocyanate/propidium iodide), and a cell migration assay (Transwell) were used to analyze cell activity. Western blot analysis and quantitative reverse-transcription polymerase chain reaction were performed to examine function-related mRNA and protein levels. Treatment with polydatin suppressed cell growth and migration in both cell lines. Moreover, polydatin induced cell apoptosis in both parental and paclitaxel-resistant cells, and cell-cycle arrest in the S phase. Furthermore, it altered the expression of various proteins associated with cell growth (Ki67, p21, cyclin A, cyclin E, and cyclin-dependent kinase 2), migration (matrix metalloproteinase-2 [MMP-2], MMP-9, and tissue inhibitor of metalloproteinase-1), apoptosis (poly[ADP-ribose] polymerase 1 and caspase 3), and drug resistance (p-glycoprotein 1, lung resistance-related protein 1, growth arrest and DNA damage-45α, glutathione S-transferase π, and heat shock protein 27) in paclitaxel-resistant osteosarcoma cells. Cells transfected with myr-Akt caused obvious upregulation and activation of Akt, which were significantly attenuated via polydatin treatment. In conclusion, polydatin may enhance the chemosensitivity of osteosarcoma cells to paclitaxel.