P-Glycoprotein Overexpression Is Associated With Cisplatin Resistance in Human Osteosarcoma

Background/Aim: Osteosarcoma (OS) is a diagnosed primary cancer of the bone. Despite the great advances that have been made during the past decades in OS therapy, drug resistance and tumor recurrence are still major problems. It is urgent to find novel strategies to overcome drug resistance in order to prolong the survival time of OS patients. Materials and Methods: Cell viability was investigated by the cell count kit-8 (CCK-8) and colony formation assays. P-Glycoprotein (P-gp) expression was analyzed by RT-qPCR and western blot. A xenograft mouse model was used to identify the synergistic efficacy of a P-gp inhibitor with cisplatin. Student's t-test was used to determine statistically significant differences. Results: P-gp expression levels were associated with cisplatin efficacy in OS patients. OS cells with higher P-gp expression were more resistant to cisplatin. Knockdown or inhibition of P-gp sensitized OS cells to cisplatin. Conclusion: Downregulating the expression of P-gp in OS maybe a promising strategy to overcome cisplatin resistance.