TRAIL联合多柔比星作用于骨肉瘤的实验研究

Apoptosis induced by the combination of TRAIL and doxorubicin in osteosarcoma cells

背景与目的肿瘤坏死因子相关的凋亡诱导配体(TNFrelatedapoptosisinducingligand,TRAIL)是近年发现的肿瘤坏死因子家族新成员,显著特点是它仅诱导肿瘤细胞凋亡,对正常细胞无毒性作用。TRAIL可作为骨肉瘤靶向治疗的潜在有效药物,但单独使用时已被证明作用有限。而多柔比星可对肿瘤细胞产生广泛的生化效应,为细胞周期非特异性药物,有强烈的细胞毒性作用,可嵌入DNA而抑制核酸的合成导致细胞死亡。本研究旨在探讨TRAIL联合低剂量化疗药物多柔比星对骨肉瘤MG-63细胞的凋亡诱导效应。方法MTT法测定TRAIL和多柔比星对MG-63细胞单独及联合作用的细胞凋亡率,DNA凝胶电泳及流式细胞仪检测细胞凋亡。结果1000ng/ml的TRAIL与4.3μmol/mL多柔比星合用于MG63细胞24h时后,测细胞抑制率为36.65%,明显高于单用TRAIL(1000ng/ml)时的21.67%及单用多柔比星(4.3μmol/ml)时的10.25%(P<0.01)。细胞超微结构观察及凋亡率测定均显示,合用比单用有更多的骨肉瘤细胞凋亡。TRAIL联合应用多柔比星能显著增强对MG-63的杀伤、抑制增殖及诱导凋亡作用,明显高于单独应用TRAIL组或多柔比星组(P<0.05),并且这种作用随培养时间延长及药物浓度增加而增强。结论TRAIL是一种有望应用于临床的新型生物制剂。TRAIL与多柔比星对诱导骨肉瘤细胞凋亡具有协同作用,能高效杀灭骨肉瘤细胞。

Background and purpose： TNF related apoptosis inducing ligand （TRAIL） is a new member of the TNF family that has recently been discovered. Its notable feature is to induce apoptosis only in tumor cells, but has no impact on normal cells. TRAIL could be a potential candidate for targeted therapy in osteosarcoma, but its efficacy was limited when used as a single agent. Doxorubicin （Dox） is a chemotherapeutic agent that is not cell cycle specific, and has intensive cytotoxic effect. Dox can imbed DNA so that it inhibits the synthesis of nucleic acid. The purpose of this paper was to investigate the apoptosis-inducing effect of TRAIL combined with Dox on osteosarcoma cell line MG-63. Methods： MTT assays were used to evaluate the cytotoxic effect of TRAIL and Dox on MG-63 cells. DNA electrophoresis and flow cytometry were used to quantitate apoptosis. Results： The cells were incubated with the combination of TRAIL（ 1000 ng/mL ） and DOX （4.3μmol/mL） for 24 h, the apoptotic rate was 36.65% in a dose- and time-dependent manner, compared to 21.87% when treated with either 1000 ng/mL TRAIL alone or 10.25% with 4.3μmol/mL Dox alone for 24h）, P 〈 0.01. More apoptotic bodies could be observed by microscope in the combined group than the others and had the most cytotoxic effect against tumor cells in all three groups. Conclusions： TRAIL can synergistically interacted with Dox in terms of induction of apoptosis in Osteosarcoma Cells. TRAIL could be further investigated as a chemotherapy sensitizer in a clinical setting.