OBJECTIVETo research the cytotoxicity and in vitro antiproliferative effect of the six flavone compounds extracted from Laggera pterodonta.

METHODThe cytotoxicity on the normal cells and antiproliferative effect on tumor cells were tested by MTT assay, and then the preliminary structure-activity relationship was analysed. The phase distribution of the cell cycle and apoptosis rate were analyzed by flow cytometry.

RESULTThe results of MTT assay showed 5,7,3',4'-tetramethoxy-3-hydroxyflavone and chrysosplenetin B inhibited growth of A549 and Hela cells significantly with a dose dependent mode, while exhibited low cytotoxicity to the two normal cells, Vero and EVC304. Both compounds contain ortho-phenolic methoxyl moietys in their structures. Flow cytometry analysis revealed that Hela cells treated with increasing quantities of chrysosplenetin B increased the percentage of cells in the G2/M phase, and Hela and A549 cells treated with increasing quantites of the 5,7,3',4'-tetramethoxy-3-hydroxyflavone and chrysosplenetin B increased the apoptosis rates.

CONCLUSIONThe 5,7,3',4'-tetramethoxy-3-hydroxyflavone and chrysosplenetin B extracted from L. pterodonta showed high antiproliferative effect on cancer cells with low cytotoxicity on normal cells, and took the effects on A549 and Hela cells through the hold-up of the G2/M phase of the cell cycle and induction of the apoptosis.