丙戊酸联合顺铂对体外人非小细胞肺癌细胞的增殖抑制作用

目的探讨丙戊酸（VPA）联合顺铂（DDP）对人非小细胞肺癌细胞A549、NCI．H460增殖抑制及细胞凋亡的影响，以及两药联合影响肺癌细胞增殖的机制。方法3组不同质量浓度的VPA与DDP单药及联合作用于人非小细胞肺癌细胞A549、NCI—H460，培养24、48、72h后，观察细胞数量和形态的变化，用MTF法分析药物对细胞增殖的抑制率（IR）及联合用药对细胞增殖抑制率q值，Hoechst／PI双染检测细胞凋亡的数量变化，Westernblot观察联合用药对Bcl．2、Caspase．3、Caspase．8蛋白的表达变化。结果培养48h后，各用药组细胞数目减少十分明显，其中VPA＋DDP组较单独用药组减少更为显著，其细胞形态发生较大改变；MTF法及q值计算结果显示，对A549细胞，VPA的增殖抑制作用呈现明显的时间与浓度依赖性，在高质量浓度时（300mg·L-1）与DDP具有协同作用；对NCI—H460细胞，当VPA的质量浓度≤100mg·L-1时，未显示出明显的时间与浓度依赖性，所有浓度均未显示出VPA与DDP的协同作用。VPA联合DDP可以进一步促进A549与NCI—H460的细胞凋亡，导致两细胞中凋亡因子Bcl-2水平的明显下调。联合作用对A549细胞更为明显，可能与该细胞中抑凋亡因子Bcl-2低表达及促凋亡因子Caspase-3、Caspasel8高表达有关。结论VPA能增强DDP对人非小细胞肺癌细胞的增殖抑制作用，联合作用的协同性与药物浓度及细胞类型有关，不同类型细胞对药物敏感性的差异可能与细胞自身表达的凋亡因子的含量有关。

Inhibitory effect of valproic acid combined with cisplatin on proliferation in human non-small cell lung cancer cells

AIM To investigate the effect of proliferation and the mechanism of apoptosis on human non-small cell lung cancer A549 and NCI-H460 cells exposed to valproic acid （VPA） combined with cisplatin（DDP）. METHODS A549 and NCI-H460 cells were treated with VPA and DDP alone and in combination at three sets of concentration after 24, 48 and 72 h. The changes of cell number and morphology were observed and cell proliferation inhibition rate （IR） and q-value of combination therapy were studied by MTF assay. The variation of the number of apoptotic cells and the protein expression of Bcl-2, Caspase-3 and Caspase-8 in combination was determined by Hoechst/PI double staining and Western blot. RESULTS The reducing of the number of cells in each treatment group was very obvious after 48 h and the VPA ＋ DDP group decreased more significantly than the monotherapy group, the cell morphology changed greatly. The method MTI＂ and the q-value showed that in A549 cells, the proliferation of VPA was significantly dependent on time and concentration, and had a synergistic effect with DDP at high concentrations （300 mg＇L-1）. In NCI-H460 cells,the VPA did not show significant dependence on time and concentration when p（VPA）≤ 100 mg· L-1, and all concentra- tions did not show a synergy of VPA ＋ DDP. VPA ＋ DDP can promote the apoptosis of the A549 and NCI-H460 cells, and apoptotic factors of Bcl-2 was significantly reduced. The combined effect was more obvious on A549 cells, the reason may be associated with the antiapoptotic factor Bcl-2 low expression and pro-apoptotic factor Caspase-3, Caspase-8 high expression. CONCLUSION VPA can enhance the proliferation of DDP on human lung cancer cell, the synergy of com- bined effect is related to the concentration of drugs and the cell types, and the differences of the sensitivity of drugs by different types of cells may be associated with the content of apoptotic factors expressed by ceils.