Preliminary evaluation of antitumor effect and induction apoptosis in PC-3 cells of extract from Patrinia heterophylla

Patrinia heterophylla Bunge, Caprifoliaceae, is a traditional Chinese medicine that has been used for cancer therapy. In our study, a panel of human cancer cells was treated with extract of Patrinia heterophylla Bunge. (PHEB), MTT study showed that PC-3 Human prostate adenocarcinoma was the most responsive (IC50 9.21±0.32 μg/mL) one to cell growth inhibition, the further study also demonstrated that PHEB could inhibit the proliferation of PC-3 based on a concentrationand time-dependent manner. The transplanted model of sarcoma 180 (S180) and hepatoma 22 (H22) was established in mice, the study demonstrated that i.p. administration of 20, 40, 60 mg/kg PHEB exhibited a significant inhibitory effect on the growth of transplantation tumor, with inhibition rate 23.9, 48.4 and 53.6% on S180 and 21.0, 46.3 and 57.2% on H22, respectively. To investigate the molecular mechanism of PHEB in PC-3, the morphological changes of apoptosis were observed by fluorescent microscopy, apoptosis rate was analyzed by flow cytometry (FCM). Morphological characterizations such as apoptotic bodies and membrane blebs were shown by microscopy. The increase of an early apoptotic population was observed in a dose-dependent manner. These results suggest that PHEB has anti-tumor effects and its mechanism is attributed partially to apoptosis induced.