Diallyl trisulfide reverses drug resistance and lowers the ratio of CD133+ cells in conjunction with methotrexate in a human osteosarcoma drug-resistant cell subline.

P-glycoprotein (P-gp) overexpression and tumor stem cells are thought to be important factors in the cross-resistance of cancer cells. There have been no studies on whether diallyl trisulfide (DATS) can reverse drug resistance in human osteosarcoma cells. In the present study, we demonstrated that DATS down-regulated P-gp expression and reversed drug resistance. DATS and methotrexate (MTX) decreased the ratio of drug-resistant human osteosarcoma cells positive for CD133 (a tumor stem cell marker). To the best of our knowledge, this is the first evidence that DATS can reverse drug resistance and lower the ratio of CD133+ cells in human osteosarcoma cells in conjunction with MTX.