Abstract:Objective To investigate the molecular mechanism of baicalein inhibiting proliferation of leukemic cells. Methods A variety of leukemia cells were treated with different concentrations of baicalein, and the number of viable cells was obtained by cell counting. 6133/MPL W515L cells were used to study the molecular mechanism of baicalein inhibition of cell proliferation, cell cycle distribution and apoptosis. Results Baicalein could inhibit the proliferation of all the tested leukemia cells, except for the non malignant G1ME cells from mouse embryonic stem cells, suggesting that baicalein might specifically inhibit the proliferation of malignant leukemia cells. Cell cycle analysis showed that the different concentrations of baicalein had different effect on apoptosis of 6133/MPL W515L cells (p < 0.05), suggesting that may lead to the apoptosis of 6133/MPL W515L cells and cell cycle arrest in G1 phase. In addition, baicalein may induce apoptosis by inhibiting MAPK/Erk pathway and activating caspase-3. Z-VAD alone did not affect cell proliferation, but it could not save the cell proliferation inhibition induced by baicalein, suggesting that caspase activation may not be the key pathway of baicalein inhibiting cell proliferation. Conclusions Baicalein can induce apoptosis and cell cycle arrest and inhibit the proliferation of leukemia cells. It may be an effective candidate for anti-leukemia drugs.