In Vitro and In Vivo Antitumor Effects of n-Butanol Extracts of Pterocephalus hookeri on Hep3B Cancer Cell

Pterocephalus hookeri is a widely applied Tibetan medicinal prescription for treatment of diseases such as flu, rheumatoid arthritis, and enteritis in China. It has been reported that Pterocephalus hookeri has anti-inflammatory and analgesic actions. However, the antitumor activity of Pterocephalus hookeri remains unknown. In the present study, we demonstrate that n-butanol extracts of Pterocephalus hookeri (YSC-ZDC) has a strong antitumor activity against hepatoma carcinoma cell in vitro and in vivo. YSC-ZDC inhibited proliferation of all cancer cell lines and significantly inhibited Hep3B cells proliferation in a dose- and time-dependant manner. Transmission electron microscopy, hoechst 33258 staining, and flow cytometry analysis revealed that YSC-ZDC induced apoptosis in Hep3B cells. YSC-ZDC treatment dramatically inhibited PDK1 and Akt phosphorylation in Hep3B cells. Moreover, YSC-ZDC increased Bax expression and inhibited Bcl-2 expression. In addition, YSC-ZDC inhibited growth hepatoma xenografts in vivo with no effect on body weight and spleen index. Consistent with results in vitro, YSC-ZDC increased Bax expression and inhibited Bcl-2 expression in tumor tissue. Taken together, this study shows YSC-ZDC with an antitumor activity both in vitro and in vivo. Its mechanism underlying is related to blocking of the Akt pathway and regulation of Bcl-2 family proteins expression.