OBJECTIVETo study the effect of quercetin on the apoptosis of human PC-3 cells.

METHODSHuman PC-3 cells were cultured in vitro and then treated with quercetin at the concentrations of 50, 100, 150, 200 and 250 micromol/L. The inhibition rate of quercetin on the PC-3 cells was detected by MTT, the apoptosis of the cells determined by flow cytometry, and the changes of the cellular ultramicrostructure observed by transmission electron microscopy.

RESULTSQuercetin markedly inhibited the proliferation of PC-3 cells in vitro in a time- and dose-dependent manner. Its inhibition rates were (3.01 +/- 1.32)%, (4.84 +/- 1.73)%, (20.35 +/- 1.30)%, (16.78 +/- 1.89)% and (27.25 +/- 4.01)% at 24 hours, and (10.18 +/- 1.16)%, (6.22 +/- 0.04)%, (24.29 +/- 4.19)%, (22.4 +/- 4.26)% and (41.42 +/- 5.43)% at 48 hours in the 50, 100, 150, 200 and 250 micromol/L groups, respectively, with statistical significance at the concentration of > 150 micromol/L (P < 0.05). Flow cytometry showed that the apoptosis of PC-3 cells was increased with the elevated concentration and prolonged time of Quercetin treatment, (19.10 +/- 0.28)% and (26.55 +/- 0.78)% at 24 hours, and (27.65 +/- 1.06)% and (38.30 +/- 5.96)% at 48 hours in the 150 and 200 micromol/L groups, respectively (P < 0.05). Typical changes in the morphology of the cells were observed under the transmission electron microscope.

CONCLUSIONQuercetin can inhibit the proliferation and induce the apoptosis of human PC-3 cells, but its action mechanism remains to be further investigated.