ABSTRACT
<p><b>AIM</b>To investigate the effect of triptolide on proliferation of PC12 cells and the mechanism involved in the effect, and provide evidence for clinical use of triptolide in treatment of tumor.</p><p><b>METHODS</b>By means of morphological observation, MTT assay, flow cytometry (FCM) and RT-PCR, the effect of triptolide on the proliferation of PC12 cells was observed in vitro.</p><p><b>RESULTS</b>The proliferation inhibition was found on PC12 cells incubated with triptolide (5 x 10(3) or 25 x 10(3) g/L) for 24 h, 48 h and 72 h, and with the higher concentration of triptolide, the inhibition was stronger. Low concentration of triptolide (1 x 10(3) g/L) showed no significant effect on proliferation of PC12 cells. After treatment of PC12 cells with triptolide (5 x 10(3) g/L) for 24 h, increased percentage of G0-G1 phase and decreased percentage of S phase were found. Expression of translational elongation factor 2A3-2 was reduced after treatment of PC12 cells with triptolide (5 x 10(3) g/L). The expression of 2A3-2 was weaker in PC12 cells treated with triptolide for 48 h than for 24 h.</p><p><b>CONCLUSION</b>Triptolide inhibits the proliferation of PC12 cells. The inhibition may be realized by changing the expression of 2A3-2 and preventing the transition from G0-G1 phase to S phase.</p>