紫杉醇诱导骨肉瘤细胞系凋亡的体外研究

目的研究抗微管新药紫杉醇对成骨肉瘤细胞系U-2OS的生长抑制及诱导凋亡作用,并探讨其诱导凋亡作用的机制。方法将不同浓度的紫杉醇作用于成骨肉瘤细胞系U-2OS,应用形态学观察、台盼蓝染色、流式细胞术、电镜、原位末端标记(TUNEL)等方法,检测其诱导骨肉瘤细胞凋亡的时间效应和剂量效应,并与其它化疗药物比较。结果紫杉醇对U-2OS细胞具有生长抑制及诱导凋亡作用,且呈时间依赖和剂量依赖性。表现为细胞G2/M期阻滞、出现明显的凋亡峰;有核碎裂、染色体凝集、DNA断裂等凋亡特征,并出现大量多核细胞。经其它化疗药物诱导的U-2OS细胞未出现多核现象。结论紫杉醇通过抑制细胞有丝分裂,对骨肉瘤细胞有明显的生长抑制及促凋亡作用,且其作用有独特的机制。

In vitro studies of paclitaxel-mediated apoptosis in osteosarcoma cell line

Objective To study the growth inhibitory and apoptosis inducting effect of paclitaxel on human osteoblastic cell line U-2 OS. Methods U-2 OS cells were treated with various concentrations of paclitaxel. Proliferation was determined by cell count in a Neubauer cytometer chamber. Viability was assessed by trypanblau dye exclusion. Paclitaxel induced morphologic alterations were visualized, using light and transmission electron microscopy. The extent of paclitaxel induced apoptosis was determined by flow cytometry and immunohistochemical detection (TdT mediated dUTP nick end labeling technique, TUNEL). Results Paclitaxel had a growth inhibitory and apoptosis inducting effect on U-2 OS cell. The cell treated with paclitaxel initially show G2/M arrest; follow by apoptosis. A characteristic apoptosis change including nuclear disintegration and chromatin agglomerate were displayed. Lots of multinucleate cells appeared, which was not seen on the cell treated with other chemotherapeutic agents such as cisplatin and adriamycin. Also, extensive DNA cleavage was detected by immunohistochemical technique. Conclusion Paclitaxel has an obvious growth inhibitory and apoptosis inducting effect on osteosarcoma cell line by induce a G2/M arrest and inhibit the mitosis. The effect of paclitaxel displays a time dependent and dose dependent manner.