Abstract
In this study two monocytic leukemia cell lines, U937 and THP-1 cells, were used to investigate the anti-proliferation effects caused by ponicidin. Cell viability was measured by an MTT assay. Cell apoptosis was assessed by flow cytometry as well as DNA fragmentation analysis. Cell morphology was observed using an inverted microscope and Hoechst 33258 staining. RT-PCR and Western blot analysis were used to detect survivin as well as Bax and Bcl-2 expressions after the cells were treated with different concentrations of ponicidin. The results revealed that ponicidin could inhibit the growth of U937 and THP-1 cells significantly by induction of apoptosis. The suppression was in both time- and dose-dependent manner. Marked morphological changes of cell apoptosis were observed clearly after the cells were treated with ponicidin for 48∼72 h. RT-PCR and Western blot analysis demonstrated that both survivin and Bcl-2 expressions were down-regulated remarkably while Bax expression remained constant before and after apoptosis occurred. We therefore conclude that ponicidin has significant anti-proliferation effects by inducing apoptosis on leukemia cells in vitro, downregulation of survivin as well as Bcl-2 expressions may be the important apoptosis inducing mechanisms. The results suggest that ponicidin may serve as potential therapeutic agent for leukemia.
Highlights
Ponicidin, a diterpenoid compound, is extracted and purified from the traditional Chinese herbsRabdosia rubescens or Isodon japonicas [1, 2]
In order to understand the roles of ponicidin in leukemia cells and possible clinical application of ponicidin in leukemia therapy, we have investigated the effects of different concentrations of ponicidin on cell viability and apoptosis on monocytic leukemia cells in vitro
The expressions of Survivin as well as Bcl-2 and Bax in U937 and THP-1 cells were examined by RT-PCR before and after the cells were treated with different concentrations of ponicidin for 72 h
Summary
A diterpenoid compound, is extracted and purified from the traditional Chinese herbs. Ponicidin has been reported to have a variety of biological effects such as immunoregulatory and anti-inflammatory functions as well as anti-viral functions especially in the upper respiratory tract infection [3]. Later studies have shown that ponicidin can promote the cell-killing activity of antiherpes prodrugs acyclovir (ACV). New data have demonstrated that ponicidin can inhibit the growth and metastasis of prostate cancer due to its significant antiangiogenic activity [6]. Ponicidin has been proved to be very effective in a variety of malignancies, many of its anti-tumor mechanisms remain to be demonstrated. No detailed data are available about the role and mechanisms of ponicidin in leukemia cells. In order to understand the roles of ponicidin in leukemia cells and possible clinical application of ponicidin in leukemia therapy, we have investigated the effects of different concentrations of ponicidin on cell viability and apoptosis on monocytic leukemia cells in vitro
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
