Ferulic acid reverses ABCB1 mediated paclitaxel resistance in MDR cell lines.
Multidrug resistance (MDR) remains a major obstacle in cancer chemotherapy. The use of the dietary phytochemicals as chemosensitizing agents to enhance the efficacy of conventional cytostatic drugs has recently gained the attention as a plausible approach for overcoming the drug resistance. The aim of this study was to investigate whether a naturally occurring diet based phenolic acid, ferulic acid, could sensitize paclitaxel efficacy in ABCB1 overexpressing (P glycoprotein) colchicine selected KB Ch(R)8 5 cell line. In vitro drug efflux assays demonstrated that ferulic acid inhibits P glycoprotein transport function in drug resistant KB Ch(R)8 5 cell lines. However, ferulic acid significantly downregulates ABCB1 expression in a concentration dependent manner. Cytotoxicity assay reveals that ferulic acid decreased paclitaxel resistance in KBCh(R)8 5 and HEK293/ABCB1 cells, which indicates its chemosensitizing potential. Clonogenic cell survival assay and apoptotic morphological staining further confirm the chemosensitizing potential of ferulic acid in drug resistant KB Ch(R)8 5 cell lines. Ferulic acid treatment enhances paclitaxel mediated cell cycle arrest and upregulates paclitaxel induced apoptotic signaling in KB resistant cells. Hence, it has been concluded that downregulation of ABCB1 and subsequent induction of paclitaxel mediated cell cycle arrest and apoptotic signaling may be the cause for the chemosensitizing potential of ferulic acid in P gp overexpressing cell lines.
European journal of pharmacology