Abstract: The ability of two dihydrostilbene derivatives erianin and chrysotoxine from Dendrobium chrysotoxum to reverse multidrug resistant (MDR) cells was investigated using murine B16 melanoma cells transfected with the human MDR-1 gene and crossresistant to vinblastine and adriamycin (B16/h MDR-1 cells). Both of the two compounds were shown to increase the accumulation of adriamycin, the P-glycoprotein (P-gp) substrate, in B16/h MDR-1 transfectants.

Key words: Dihydrostilbene, Erianin, Chrysotoxine, Multidrug resistance (MDR), Pglycoprotein (P-gp)