一氧化氮对鼻咽癌CNE-2细胞株化疗增敏效应的研究

Investigation of chemosensitization induced by nitric oxide on nasopharyngeal carcinoma CNE-2 cells

目的探讨外源性一氧化氮(NO)在顺铂(DDP)作用于CNE-2细胞的过程中是否存在增敏效应,为提高鼻咽癌化疗疗效提供实验和理论依据。方法分别使用不同浓度NO供体药物硝普钠(SNP)、DDP及二者联合干预CNE-2细胞,采用硝酸还原酶法检测NO的浓度,镜下观察细胞形态学变化,CCK-8法检测细胞增殖抑制率以及流式细胞仪检测细胞凋亡。结果 (1)SNP呈浓度依赖方式抑制CNE-2细胞的增殖、促进凋亡;(2)上清液中NO浓度与SNP浓度呈正相关,有统计学意义(r=0.968,P<0.001);(3)DDP+SNP联合组与SNP组和DDP组相比,CNE-2细胞形态学差异显著,漂浮细胞显著增多,贴壁数量逐渐减少并失去原有形态;(4)当SNP 600μmol/L时对细胞增殖无明显影响,然而联合DDP后较单用DDP组细胞抑制率显著提高(t=9.049,P<0.001);(5)SNP组与DDP联用时CNE-2细胞凋亡率上升,较单用SNP、DDP组显著增强(t=-19.816,P<0.001;t=-5.242,P=0.035)。结论外源性NO能抑制CNE-2的增殖,其抑制效应与NO浓度呈正相关;合适浓度的外源性NO可在对细胞本身不产生明显毒性的情况下显著增强DDP对CNE-2细胞株的化疗敏感性。

Objective To investigate whether exogenous nitric oxide（ NO） could increase chemosensitization to cisplatin（ DDP） in CNE2 cells,and to provide an experimental and theoretical basis for improving the effectiveness of chemotherapy for nasopharyngeal carcinoma. Methods CNE-2 cells were treated with various concentrations of sodium nitroprusside（ SNP）,DDP,and both chemicals. The nitrate reductase method was used to detect the concentration of NO. Morphological changes of cells were observed using an inverted phase contrast microscope and CCK8 assays were used to examine the viability of cells. Flowcytometry was applied to detect apoptosis in NPC cells. Results（ 1） The concentration of NO was positively correlated with the concentration of SNP,and this correlation was statistically significant（ r = 0.968,P〈0.05）.（ 2） Compared with the CNE-2 cells in the SNP group,DDP group,and control group,the CNE-2 cells in the DDP＋SNP group showed more extensive morphological changes.（ 3） The inhibitory effects of SNP＋DDP were significantly greater than those of SNP or DDP alone（ P〈0.05）.（ 4） Compared with the groups treated with SNP or DDP individually,flowcytometry showed that the apoptosis rate of CNE-2 cells was significantly higher in the group treated with both SNP and DDP（ P〈0.05）. Conclusion Exogenous NO can inhibit CNE-2 proliferation,and the inhibitory effect was positively correlated with the concentration of NO. The proper concentration of exogenous NO can significantly enhance the chemosensitivity of CNE-2 cells to DDP,without substantial toxicity.