The Chinese medicinal herb Tripterygium wilfordii Hook and one of its active components triptolide, a diterpenoid triepoxide, have been shown to have anti-inflammatory, anti-fertility and anti-neoplastic activities. Recently, triptolide was shown to have antitumor properties by suppressing the growth and inducing apoptosis of a broad range of human tumor cells. To identity the anticancer mechanism of triptolide, we assayed its effect on apoptosis, cell cycle distribution. The results showed that triptolide induced apoptosis in MCF-7 cells, without affecting the cell cycle distribution. Our study reports here for the first time that the activity of the apoptotic induction may participate in the anti-proliferative activity of triptolide in MCF-7 cells.
