Gencer Salih, Irmak Yazicioğlu Meliha Burcu
Department of Genetics and Bioengineering, Fatih University Faculty of Arts and Science, İstanbul, Turkey.
Turk J Gastroenterol. 2011;22(2):145-51. doi: 10.4318/tjg.2011.0183.
BACKGROUND/AIMS: Reactive oxygen species are involved in tumor progression but how they function is not well understood. In this study, we investigated and compared the effects of hydrogen peroxide on the survival, apoptosis, accumulation of oxidative stress, and matrix metalloprotein-7 gene expression on human gastric carcinoma MKN-45 and 23132/87 cells.
The cell lines were exposed to hydrogen peroxide in a dose- and time-dependent manner. The surviving cells were detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. The oxidative stress was analyzed by an oxidative stress marker, 2,7-dichlorofluorescein diacetate, under fluorescence microscope. The effect of oxidative stress on the apoptotic behavior, caspase-3 activity, and matrix metalloprotein-7 gene expressions of the cell lines were determined, respectively, by TUNEL, caspase-3 activity assay, and quantitative real-time polymerase chain reaction.
Exposure of the gastric cancer cells to oxidative stress resulted in dose- and time-dependent decrease in the survival of the cell lines. While MKN-45 cells had oxidative stress, increased apoptosis with no caspase-3 activity, and increased matrix metalloprotein-7 expression following hydrogen peroxide exposure, 23132/87 cells showed none, with internal oxidative stress accumulation prior to hydrogen peroxide exposure.
The two gastric cancer cell lines responded differently to oxidative stress conditions, and unlike in 23132/87 cells, matrix metalloprotein-7 gene expression was shown to be affected by external hydrogen peroxide in MKN-45 cells.
背景/目的：活性氧参与肿瘤进展，但其作用机制尚不清楚。在本研究中，我们研究并比较了过氧化氢对人胃癌MKN-45和23132/87细胞的存活、凋亡、氧化应激积累及基质金属蛋白酶-7基因表达的影响。
将细胞系以剂量和时间依赖性方式暴露于过氧化氢。通过3-(4,5-二甲基噻唑-2-基)-2,5-二苯基四氮唑溴盐法检测存活细胞。在荧光显微镜下，用氧化应激标记物2,7-二氯荧光素二乙酸酯分析氧化应激。分别通过TUNEL法、半胱天冬酶-3活性测定法和定量实时聚合酶链反应，测定氧化应激对细胞系凋亡行为、半胱天冬酶-3活性及基质金属蛋白酶-7基因表达的影响。
将胃癌细胞暴露于氧化应激下，导致细胞系存活呈剂量和时间依赖性下降。过氧化氢暴露后，MKN-45细胞出现氧化应激，凋亡增加但半胱天冬酶-3无活性，基质金属蛋白酶-7表达增加；而23132/87细胞未出现上述情况，且在过氧化氢暴露前存在内源性氧化应激积累。
两种胃癌细胞系对氧化应激条件反应不同，与23132/87细胞不同，MKN-45细胞中基质金属蛋白酶-7基因表达显示受外源性过氧化氢影响。
