A COMPARISON STUDY OF THE IN VITROANTICANCER ACTIVITY AND MECHANISM OF ETHANOL EXTRACTS FROM MYCELIA OF DIFFERENT GANODERMA LUCIDUM STRAINS

MTT assay was applied to compare the anticancerous effect of ethanol extract from mycelia of eight Ganoderma lucidum strains against human acute promyelocytic leukemia HL-60 cell line. Morphological observation, flow cytometric DNA content analysis and Annexin-V/PI bivariate assay for cell cycle and apoptosis detection were employed to study the mechanism of antitumor activity. Among eight Ganoderma lucidum strains, ethanol extract from strain L5 was identified to possess a high anticancerous activity. The percentage of inhibition was 91.4±0.9% (72h, 125ng/mL). At the 48th hour, 13.3 % cells underwent early apoptosis. In comparison with control, the percentage of G0/G1 cells elevated 15.9%, while that of S cells decreased 8.4% and G2/M cells went down 7.6%. The study demonstrates the ethanol extracts from mycelium of Ganoderma lucidum strains can effectively inhibit the HL-60 cell proliferation in vitro. Such activity is strain-dependent and the inhibitory mechanisms might relate to the arrest of cell cycle and induction of apoptosis.