Sensitisation of ovarian cancer cells to cisplatin by flavonoids from Scutellaria barbata.

Combination of natural components with anticancer drugs is a new strategy for cancer chemotherapy to increase antitumour responses. In this study, we investigated the sensitisation effects of nine flavonoids from Scutellaria barbata to cisplatin (CDDP) on human ovarian cancer cells. The combinations of three flavonoids with CDDP showed the synergistic effects. The intracellular reactive oxygen species and the antioxidant activity were measured. The data suggest that the synergistic effects of flavonoids with CDDP on ovarian cancer cells did not directly correlate with their redox properties, but could be associated with the positions of hydroxyl group and methoxy group of flavonoids.