BACKGROUND:Several studies have reported that quercetin can inhibit the proliferation and migration but promotes apoptosis of tumor cel s. OBJECTIVE:To explore the effect of quercetin on the proliferation and apoptosis of glioma stem cel s and the signal pathway involved. METHODS:Glioma stem cel s were isolated by immunomagnetic beads and treated in culture medium containingdifferent concentrations of quercetin (0, 25, 50, 100μmol/L). Cel proliferation was measured by MTT and apoptosis measured by flow cytometry at 48 hours after culture. The expression levels of Bcl-2, Bax and survivin, which are related to apoptosis, were detected by western blot. The expression of proliferating cel nuclear antigen (PCNA), which is related to proliferation, was also detected by western blot. The expression of STAT3 and p-STAT3 was also determined by western blot. RESULTS AND CONCLUSION:(1) Compared with the control (0μmol/L) group, quercetin inhibited the proliferation of glioma stem cel s in a dose-depended manner (P<0.05). With the increase of the concentration of quercetin, the expression of PCNA was increased (P<0.05). (2) Quercetin induced apoptosis of glioma stem cel s dose-dependently (P<0.05). With the increase of the concentration of quercetin, the expression of Bcl-2 and survivin was decreased, while the expression Bax was increased. (3) Quercetin could also inhibit phosphorylation of STAT3 dose-dependently, but the level of STAT3 was not changed. To conclude, these results show that quercetin could inhibit the proliferation of glioma stem cel s and promote apoptosis via the STAT pathway.