摘要
AIM： To evaluate the anticancer property of the dried latex （DL） of Calotropis procera, a tropical medicinal plant, in the X15-myc transgenic mouse model of hepatocellular carcinoma and to elucidate its mechanism of action in cell culture. METHODS： The young transgenic mice were orally fed with the aqueous suspension of DL （400 mg/kg for 5 d/wk） for 15 wk and their liver was examined for histopathological changes at 20 wk. Serum levels of vascu- lar endothelial growth factor （VEGF） were also measured in these animals. To characterize the active fraction, DL was extracted with petroleum ether followed by methanol. The methanolic extract was sub-fractionated on a silica gel G column using a combination of non-polar and polar solvents and eleven fractions were obtained. Each fraction was analysed for cytotoxic effect on hepatoma （Huh7） and non-hepatoma （COS-1） cell lines and nontransformed hepatocytes （AML12） using tetrazolium （MTT） assay. Finally, the mechanism of cell death was investigated by measuring the levels of Bcl2, caspase 3 and DNA fragmentation. RESULTS： DL treatment of mice showed a complete protection against hepatocarcinogenesis. No adverse effect was observed in these animals. The serum VEGF level was significantly lowered in the treated mice as compared to control animals. Cell culture studies revealed that the methanolic extract of DL as well as its fraction 8 induced extensive cell death in both Huh-7 and COS-1 cells while AML12 cells were spared. This was accompanied by extensive fragmentation of DNA in Huh-7 and COS-1 cells. No change in the levels of canonical markers of apoptosis such as Bcl2 and caspase 3 was observed. CONCLUSION： DL of C. procera has the potential for anti-cancer therapy due to its differentJable targets and non-interference with regular pathway of apoptosis.
瞄准：评估牛角属 procera 的弄干的乳胶(DL ) 的反癌症性质，热带药用的植物，在肝细胞癌并且到的 X15-myc 转基因的老鼠模型阐明它在房间文化的行动的机制。方法：小转基因的老鼠口头上地为 15 wk 用 DL (为 5 d/wk 的 400 mg/kg ) 的水的暂停被喂，他们的肝在 20 wk 为组织病理学说的变化被检验。脉管的内皮生长因素(VEGF ) 的浆液层次也在这些动物被测量。描绘活跃部分， DL 被提取，石油醚由甲醇列在后面。methanolic 摘录是用非极、极的溶剂的联合的硅胶 G 列上的亚 fractionated，十一部分被获得。每部分用 tetrazolium (MTT ) 在肝细胞瘤(Huh7 )(AML12 ) 和 non-hepatoma (COS-1 ) 房间行和非转变的 hepatocytes 上为细胞毒素的效果被分析试金。最后，细胞死亡的机制被测量 Bcl2 的层次调查， caspase 3 并且 DNA 破碎。结果：老鼠的 DL 处理对 hepatocarcinogenesis 显示出完全的保护。没有不利效果在这些动物被观察。浆液 VEGF 水平显著地作为与对照动物相比在对待的老鼠被降低。当 AML12 房间被节省时，房间文化研究表明 methanolic 在 Huh-7 和 COS-1 房间 DL 以及它的部分提取 8 导致的广泛的细胞死亡。这被 DNA 的广泛的破碎在 Huh-7 和 COS-1 房间伴随。在象 Bcl2 和 caspase 那样的 apoptosis 的正规标记的层次的没有变化 3 被观察。结论：C 的 DL。procera 与 apoptosis 的常规小径由于它的可辨的目标和不干涉为反癌症治疗有潜力。
基金
Supported by the core grant of International Centre for Genetic Engineering and Biotechnology. New Delhi
