Cantharidin reverses multidrug resistance of human hepatoma HepG2/ADM cells via down-regulation of P-glycoprotein expression.

Multidrug resistance (MDR) is a serious obstacle encountered in cancer treatment. In this study, we established an in vitro multiple drug resistant HepG2 cell line (HepG2/ADM), and characterized its MDR. This model was used to screen potential candidate chemosensitisers from over 200 purified naturally occurring compounds extracted from plants and animals. Cantharidin was found to have a significant reversal on MDR in our model. Further, our results showed that Cantharidin could significantly inhibit P-gp (P-glycoprotein) expression, mRNA transcription, as well as MDR1 promoter activity. These results suggest that Cantharidin is a novel and potent MDR reversal agent and may be a potential adjunctive agent for tumor chemotherapy.