ABSTRACT
<p><b>OBJECTIVE</b>To investigate the anti-cancer effects of crude extract from Melia toosendan Sieb. et Zucc and its possible molecular mechanisms in vitro and in vivo.</p><p><b>METHODS</b>Transonic alcohol-chloroform extraction method was used to extract toosendanin from the bark of Melia toosendan Sieb. et Zucc, and the content of toosendanin in the crude extract was measured by high performance liquid chromatography (HPLC). Anti-cancer effects of crude extract from Melia toosendan Sieb. et Zucc were investigated in in vivo and in vitro studies. In the in vitro experiment, human hepatocellular carcinoma cell lines SMMC-7721 and Hep3B were co-incubated with toosendanin crude extract of different concentrations, respectively. In the in vivo experiment, BALB/c mice were subcutaneously inoculated with mouse hepatocellular carcinoma H22 cells and treated with crude extract.</p><p><b>RESULTS</b>HPLC revealed the content of toosendanin was about 15%. Crude extract from Melia toosendan Sieb. et Zucc inhibited cancer cells growth in a dose- and time-dependent manner. The 50% inhibitory concentration (IC50, 72 h) was 0.6 mg/L for SMMC-7721 cells and 0.8 mg/L for Hep3B cells. Both high-dose [0.69 mg/(kg d)] and low-dose [0.138 mg/(kg d)] crude extract could markedly suppress cancer growth, and the inhibition rate was greater than 50%. Hematoxylin and eosin staining showed necrotic area in cancers and transmission electron microscopy displayed necrotic and apoptotic cancer cells with apoptotic bodies. Immunohistochemistry showed that the expression of Bax and Fas increased and the expression of Bcl-2 reduced.</p><p><b>CONCLUSIONS</b>Toosendanin extract has potent anti-cancer effects via suppressing proliferation and inducing apoptosis of cancer cells in vivo and in vitro. The mechanism of apoptosis involves in mitochondrial pathway and death receptor pathway.</p>
Subject(s)
Animals , Female , Male , Antineoplastic Agents , Pharmacology , Therapeutic Uses , Apoptosis , Carcinoma, Hepatocellular , Drug Therapy , Pathology , Cell Proliferation , Drugs, Chinese Herbal , Chemistry , Pharmacology , Therapeutic Uses , Immunohistochemistry , Liver Neoplasms , Drug Therapy , Pathology , Melia , Chemistry , Mice, Inbred BALB C , Mitochondria , Metabolism , Neoplasm Transplantation , Plant Extracts , Therapeutic Uses , Reference Standards , bcl-2-Associated X Protein , Metabolism , fas Receptor , MetabolismABSTRACT
Purpose: To investigate the antitumor efficacy of intra-tumoral administration of plasmid DNA expressing mIL-12 in murine H22 liver tumor models grafted subcutaneously. Methods: Plasmid encoding mIL12 was constructed and examined the expression of cytokine in the eukaryotic cell through enzyme-linked immunosorbent assay (ELISA). The proliferation assay of T lymphoblasts was performed for measuring the biological activity of expressed mIL12. After intra-tumoral administration of plasmid DNA, mean diameters of the tumor mass and survival time were measured in each murine models group. Lactic dehydrogenase ( LDH) assay was performed to examine whether or not treatment with different plasmid DNA could induce systemic cytolytic activity of lymphocytes against parental H22 cells. Histopathological analysis was operated after administration of plasmid DNA vectors in each murine model group. Results: Growth of liver tumor was significantly inhibited( F =4. 10, P =0. 03), and activity of CTL against H22 was enhanced in mIL12 gene therapy group as compared with the control group. In the focal treated with pDC511mIL12 plasmid DNA, inflammatory cell infiltration was more extensive and necrosis was more definite than control group at 1 month after DMA injection. Conclusions: Intra-tumoral administration of plasmid DNA encoding interleukin-12 could inhibit the growth of H22 liver tumor and induce the host antitumor immune response efficiently in the murine model.