中文摘要：

目的：研究鬼臼毒素衍生物SQW-76对人骨肉瘤U-2 OS细胞的抗肿瘤活性并探讨其机制。方法：噻唑蓝（methylthiazolyldiphenyl-tetrazolium bromide,MTT）法检测SQW-76及阳性对照药物依托泊苷（VP-16）和阿霉素（adriamycin,ADM）对U-2 OS细胞和成纤维细胞体外增殖的抑制作用及对U-2 OS细胞生长曲线的影响;异硫氰酸荧光素-碘化丙啶（fluorescein isothiocyanate-propidium iodide,FITC-PI）双染行流式细胞术测细胞凋亡;聚合酶链式反应（polymerase chain reaction,PCR）检测SQW-76对U-2 OS细胞凋亡相关基因表达的影响;caspase总抑制剂及caspase-3抑制剂对SQW-76诱导U-2 OS细胞凋亡的影响;JC-10线粒体膜电位检测法测SQW-76对U-2 OS细胞凋亡线粒体通路的影响;检测Caspase-3蛋白活性。结果：SQW-76在体外对U-2 OS细胞抑制作用明显,IC50值为（6.18±0.3）μmol/L,流式细胞术检测SQW-76通过凋亡途径抑制细胞,PCR发现给药后Caspase-3、caspase-9 mRNA表达水平上调,加入Caspase总抑制剂可明显抑制细胞凋亡,加入Caspase-3抑制剂可轻微抑制细胞凋亡,给药后线粒体膜电位降低,Caspase-3蛋白活性增高。结论：SQW-76在体外试验抗骨肉瘤细胞作用明显且体细胞毒性低于阳性药物VP-16、ADM,其可能通过影响caspase-9、caspase-3相关基因诱导线粒体凋亡通路诱导U-2 OS细胞凋亡。

英文摘要：

Objective ：To investigate the antitumor activity of podophyllotoxin derivatives SQW - 76 on human osteosarcoma U - 20S cells and its mechanism. Methods：The inhibition of U -20S cell and fibroblast cell proliferation and the growth curve of U -20S cells by SQW -76 and positive control drug etoposide （ VP - 16 ） and adriamycin （ ADM ） in vitro was determined by methylthiazolyldiphenyl - tetrazolium bromide （MTT） assay. Huorescein isothiocyanate - propidium iodide （ FITC - PI ） double staining for apoptosis was measured by flow cytometry. Polymerase chain reaction （PCR） was determined to detect the effect of SQW -76 on expression of genes related to apoptosis in U -20S cells. The effect of caspase total inhibitor and caspase -3 inhibitor on SQW -76 induced apoptosis in U -20S cells was evaluated; the effects of SQW-76 on apoptosis of U -20S cell mitochondrial pathway by JC -10 mitochondrial membrane potential detection method were measured; Caspase -3 protein activity was detected. Results：SQW -76 inhibited the proliferation of U -20S cells in vitro significantly. The value of IC50 was （6.18 ± 0.3） mol/L. SQW -76 inhibited U -20S ceils through apoptosis, which was detected by flow cytometry; SQW-76 was found to upregulate the expression of Caspase -3, 9 mRNA by PCR; Caspase total inhibitor and Caspase -3 inhibitor could inhibit U -20S cell apoptosis induced by SQW- 76; The mitochondrial membrane potential of U - 20S reduced after SQW - 76 treatment ; Caspase - 3 protein activity increased after SQW - 76 treatment. Conclusion： SQW - 76 can inhibit osteosarcoma cells in vitro significantly. The toxicity somatic cell of SQW-76 is lower than the positive drug VP- 16 and ADM, which may influence the caspase -9 and caspase -3 gene through mitochondrial apoptosis pathway induced apoptosis in U -20S ceils.