In addition, our research group has screened the P-glycoprotein (P-gp) inhibitory activities of four solvent fractions (hexanes, chloroform, n-butanol, and aqueous) of Indonesian medicinal plants in P-gp overexpressing multidrug resistance (MDR) cancer cell lines (MES-SA/DX5, uterine; MCF-7/ADR, breast) [27,28]. This evidence concerns the gene PGP and cancer.