phenanthrenes and Endometrial-Neoplasms

To investigate the inhibitory effect and the underlying mechanism of triptolide on cultured human endometrial carcinoma HEC-1B cells and corresponding xenograft.. For in vitro studies, the inhibition effect of proliferation on HEC-1B cell by triptolide was determined by MTT assay; cell cycle and apoptosis of the triptolide-treated and untreated cells were detected by flow cytometry. For in vivo studies, a xenograft tumor model of human endometrial carcinoma was established using HEC-1B cells, then the tumor-bearing mice were treated with high, medium, and low-dose (8 μg, 4 μg and 2 μg/day) triptolide or cisplatin at 40 μg/day or normal saline as control. The mice were treated for 10-15 days, during which body weight of the mice and volume of the xenograft were weighted. Then expression of Bcl-2 and vascular endothelial growth factor (VEGF) was analyzed by SABC immunohistochemistry.. Cell growth was significantly inhibited by triptolide as observed by an inverted phase contrast microscope; the results of MTT assay indicated that triptolide inhibits HEC-1B cell proliferation in a dose and time-dependent manner; flow cytometry showed that low concentration (5 ng/ml) of triptolide induces cell cycle arrest of HEC-1B cells mainly at S phase, while higher concentration (40 or 80 ng/ml) induced cell cycle arrest of HEC-1B cells mainly at G2/M phase, and apoptosis of the cells was also induced. High-dose triptolide showed a similar tumor-inhibitory effect as cisplatin (-50%); high-dose triptolide significantly inhibited Bcl-2 and VEGF expression in the xenograft model compared to normal saline control (P<0.05).. triptolide inhibits HEC-1B cell growth both in vitro and in mouse xenograft model. Cell cycle of the tumor cells was arrested at S and G2/M phase, and the mechanism may involve induction of tumor cell apoptosis and inhibition of tumor angiogenesis.

Topics: Animals; Antineoplastic Agents, Alkylating; Apoptosis; Cell Cycle; Cell Proliferation; Diterpenes; Endometrial Neoplasms; Epoxy Compounds; Female; Flow Cytometry; Humans; In Vitro Techniques; Mice; Phenanthrenes; Tumor Cells, Cultured; Xenograft Model Antitumor Assays

Triptolide (TP), the primary active component purified from the traditional Chinese herbal medicine Tripterygium wilfordii Hook. F (TWHF), has been shown to possess antitumor activity in several types of solid tumors. In the present study, we investigated the antitumor effect of TP in human endometrial cancer cells (HEC-1B) and elucidated its possible underlying mechanisms. HEC-1B cells were treated with various doses of TP (10, 20, 40, 80, 160 and 320 nM), and the cell viability was assessed by Cell Counting Kit-8 (CCK-8) and flow cytometric analysis. Results indicated that TP inhibited the proliferation of HEC-1B cells in a dose- and time‑dependent manner. To further investigate its mechanisms, the levels of apoptosis and the changes in caspase-3/9 expression in HEC-1B cells by pretreatment with z-VAD-fmk, a pan-caspase inhibitor, were detected by CCK-8 and western blotting. The cytotoxic effects of TP were significantly inhibited by z-VAD‑fmk. At the molecular level, TP did not effectively activate the p53 signaling pathway, but upregulated caspase-3/9 and downregulated bcl-2 without changing the bax level. Our studies revealed that TP has an effect on the apoptotic ability of endometrial cancer cells via a p53-independent mitochondrial pathway, presenting a novel strategy to evade drug resistance in tumorigenesis. The ability of TP to be a potential chemotherapeutic agent for endometrial cancer should be considered.

Topics: Amino Acid Chloromethyl Ketones; Antineoplastic Agents, Alkylating; Apoptosis; bcl-2-Associated X Protein; Caspase 3; Caspase 9; Cell Line, Tumor; Diterpenes; Down-Regulation; Endometrial Neoplasms; Epoxy Compounds; Female; Humans; Mitochondria; Phenanthrenes; Proto-Oncogene Proteins c-bcl-2; Signal Transduction; Tumor Suppressor Protein p53; Up-Regulation

Triptolide (TPL), a bioactive component of the Chinese medicinal herb Tripterygium wilfordii Hook F, induces apoptosis in some lines of human tumor cells. However, the effect of TPL on gynecologic cancer cells has not yet been well-described. We investigated the effects of TPL on cell growth, cell cycle, and apoptosis in endometrial and ovarian cancer cell lines. Furthermore, we examined global changes in gene expression after treatment with TPL. By using a list of 20 differentially expressed genes, Western blot analyses were performed on five endometrial and ovarian cancer cell lines. All cell lines were sensitive to the growth-inhibitory effect of TPL. TPL increased the proportion of cells in the S-phase of the cell cycle and induced apoptosis. cDNA microarray assay demonstrated that the treatment with TPL changed the expression of cell cycle regulators, apoptosis-related factors and cell proliferation markers. Of the gene expression changes induced by TPL treatment, up-regulation of LRAP, CDH4, and SFRP1 and down-regulation of cystatin, TNNT 1, and L1-CAM were confirmed using Western blot analysis in all the cell lines examined. We found a strong anticancer activity of TPL and identified some potential target genes of this drug, raising hopes that TPL may become a useful therapy for endometrial and ovarian cancers.

Topics: Cell Cycle; Cell Death; Cell Growth Processes; Cell Line, Tumor; Diterpenes; Down-Regulation; Endometrial Neoplasms; Epoxy Compounds; Female; Gene Expression Regulation, Neoplastic; Humans; Oligonucleotide Array Sequence Analysis; Ovarian Neoplasms; Phenanthrenes; Tripterygium