P-glycoprotein inhibitory activity of Indonesian medicinal plants in human breast cancer cells

Abstract

In order to examine their effects on the P-glycoprotein (P-gp) activity in human breast cancer cells, MCF-7/ADR, one hundred Indonesian plant extracts were screened. Among them, the five chloroform extracts of Calotropis gigantea, Curcuma aeruginosa, Merremia mammosa, Sindora sumatrana, and Zingiber cassumunar, showed the most potent P-gp inhibitory activity. When each of these extracts was treated together with the anticancer agent, daunomycin, they increased the cytotoxic activity of daunomycin up to IC50 values of less than 6.62 μM, which is a value with a positive control, verapamil. Also, other 15 plant extracts exhibited significant P-gp inhibitory activity with IC50 values between 6.62 and 13.20 μM. These prospective samples will be subjected to further laboratory phytochemical investigation to find active principles.