ABSTRACT
<p><b>OBJECTIVE</b>To study the effect of safflower injection on the proliferation and apoptosis of human leukemia cell line HEL and the relevant molecular mechanisms.</p><p><b>METHODS</b>HEL cells were treated with different concentrations of safflower injection. HEL cells without safflower injection treatment were used as the control group. MTT method was used to detect the inhibitory rate of the HEL cells at 24, 48 and 72 hours after various concentrations of safflower injection treatment (10, 20, 30, 40 and 50 mg/mL). The cell cycle and apoptosis were detected using flow cytometry and the HOXB3-mRNA expression was measured by RT-PCR at 48 hours after safflower injection treatment (10, 20 and 30 mg/mL).</p><p><b>RESULTS</b>Compared with the control group, various concentrations of safflower injection inhibited HEL cell proliferation in a dose-dependent manner (P<0.05). At 48 hours after various concentrations of safflower injection treatment, the number of treated cells in the G2/M phase increased, but that in the S phase decreased, and the apoptosis rate was significantly higher than that in the control group, with a dose-dependent manner (P<0.05). The expression of HOXB3-mRNA in safflower injection-treated cells decreased in a dose-dependent manner compared with the control group (P<0.05).</p><p><b>CONCLUSIONS</b>Safflower injection can inhibit proliferation and induce apoptosis of HEL cells in vitro, and its underlying mechanisms may involve down-regulation of the HOXB3-mRNA expression.</p>