二氧化硒对肺癌细胞增殖、凋亡及端粒酶活性的影响

Effect of Selenium Dioxide on Prolif eration,Apoptosis,and Telomerase Activity of Human Lung Ca ncer Cell Line In Vitro

背景与目的:近年研究表明硒可诱导肿瘤细胞凋亡,并且其与端粒酶活性以及肿瘤的发生密切相关。本研究旨在通过观察二氧化硒(seleniumdioxide,SeO2)对肺腺癌细胞株GLC-82的体外作用,探讨SeO2对肺癌细胞的作用机制,以及细胞凋亡与端粒酶活性之间的关系。方法:采用四甲基偶氮唑蓝(MTT)法测定不同浓度SeO2作用不同时间对肺癌GLC-82细胞生长的抑制作用;用TRAP-PCR-ELISA法检测SeO2作用前后GLC-82细胞端粒酶活性变化;采用流式细胞术(FCM)观察SeO2作用后GLC-82细胞的凋亡率;通过琼脂糖凝胶电泳法观察DNA梯状带;通过光镜和透射电镜观察GLC-82细胞的形态变化。结果:在3、10、30μmol/LSeO2作用下,GLC-82细胞的生长和端粒酶活性明显受抑制,24h时细胞生长抑制率分别为0.7%、12.8%、31.8%,72h时分别达15.1%、51.2%、61.1%;24h时端粒酶活性分别为1.173±0.029、1.127±0.067、1.050±0.098(P<0.05),48h时为1.150±0.026、1.047±0.060、0.950±0.036(P<0.05),未处理组24h和48h时端粒酶活性分别为1.227±0.032、1.167±0.023;流式细胞仪检测二倍体峰前出现凋亡峰,30μmol/LSeO2与GLC-82细胞共育24h、48h、72h后细胞凋亡率分别为0.7%、3.8%、12.1%;琼脂糖凝胶电泳显示细胞凋亡典型梯状条带;SeO2作用后,GLC-82细胞呈典型?

BACKGROUND &OBJECTIVE:It was reported that selenium could induce apoptosis of cancer cel ls;moreover,apoptosis of cancer ce lls and telomerase activity were closely re lated to the development of cancer.T his study was desig ned to investig ate the effe ct of selenium dioxide on human pulmo nary adenocarcinoma GLC-82cell to reveal its probable mechanism and the relationship between apoptosis and telomerase activity.METHODS :Methyl thiazolyl tetrazolium(MTT)method was used to determine the g row th inhibition rates of lung cancer GLC-82cells by v arious concentrations of selenium d ioxide at different time.TRAP-PCR-ELISA a ssay was used to examine the chang es o f GLC-82cells treated with selenium d ioxide.The cell apoptotic rate was measured by flow cytometry(FCM).DNA ladder was showed by DNA ag arose g el electrophoresis.The morpholog ical chang es of the cancer cells were examined under lig ht and electron mi croscope.RESULTS :After being treated with 3,10,30μmol /L selenium dioxide,the prolife ration and telomerase activity of GLC-82cells were markedly inhibi ted.The g rowth inhibition rates in G LC-82cells for 24hours were 0.7%,12.8%,a nd 31.8%;for 72hours were 15.1%,51.2%,and 61.1%,respectively.Tel omerase activity of GLC-82cells for 24hours were 1.173±0.029,1.127±0.067,and 1.050±0.098(P<0.05);for 48hours were 1.150±0.026,1.047±0.060,and 0.950±0.036(P<0.05),respectively(control g roup:1.227±0.032and 1.167±0.023,respectively).An apoptosis peak appeared before di ploid peak in FCM.Ag arose g el electrophoresis showed overt ladde r-shape band of cell apoptosis.GLC-82cells treated by selenium dioxide showed m orpholog ical characteristics of ap optotic cells.CONCLUSION:Selenium dioxide could sig nificant ly inhibit the g rowth of lung cancer GLC-82cells throug h ind ucing apoptosis and inhibiting the telomerase activity.Selenium dioxide has strong g rowth inhibitory eff ect in a dose-and time-dependant manner.