短链RNA抑制神经母细胞瘤MYCN基因表达诱发肿瘤细胞凋亡的研究

目的 探讨MYCN高扩增神经母细胞瘤肿瘤细胞中MYCN基因的表达改变对肿瘤细胞凋亡、增殖的影响.方法 采用RNA干扰抑制MYCN基因表达,荧光定量PCR法及Westernblot法检验基因表达受抑制情况;ELISA法检验肿瘤细胞凋亡情况,Western-blot法检验神经元特异性烯醇酶表达变化.结果 siRNA转染12 h、24 h MYCN mRNA表达,相对灰度值分别为0.53±0.10(对照组为1)、0.28±0.09(对照组为1.12±0.31),表达显著降低(P＜0.05);Western-blot结果显示转染12 h、24 h MYCN蛋白表达,相对灰度值分别为0.76±0.13,对照组为1.25±0.21、0.44±0.07,对照组为1.39±0.29,表达显著降低(P＜0.05);MYCN基因表达抑制后肿瘤细胞凋亡增加,抑制组DNA碎片值1.90±0.12,对照组1.13±0.09,P＜0.05;神经元特异性烯醇酶表达增高,抑制组相对灰度值为1.04±0.14,对照组相对灰度值为0.47±0.10,P＜0.05.结论 抑制MYCN基因的表达可以促进神经母细胞瘤细胞凋亡及分化.

Suppression of MYCN gene expression by siRNA induced apoptosis to neuroblastoma cells

Objective To investigate the impacts of MYCN expression alternation on apoptosis and proliferation in MYCN-amplifieation of neuroblastoma cell line.Methods Neuroblastoma cell line LAN-1 was euhured and transferred by MYCN-siRNA.The gene silencing was tested by Real time PCR and western-blot.The apoptosis and expression of neuron-specific enolase of tumor cells were measured by EIASA and western-blot,respectively.Results After transferring of siRNA for 12 h and 24 h,the densimeter recorder of MYCN mRNA was 0.53± 0.10 (vs.control 1,P＜0.05),0.28±0,09 (vs.control 1.12± 0.31,P＜0.05),respectively.Western-blot showed that the densitometric quantification of MYCN protein was 0.76±0.13 (vs.control 1.25± 0.21,P＜0.05) 12 h after siRNA transferring,while that of 24h was 0.44 ±0.07 (vs.control 1.39± 0.29,P＜0.05).After the suppression of MYCN expression,the apoptosis of tumor cells was enhanced (1.90 ±0.12 vs 1.13±0.09,P＜0.05),and the expression of neuron-speeifie enolase was increased (1.04 ± 0.14 vs 0.47 ±0.10,P＜0.05).Conclusions RNA interference could inhibit MYCN expression in vitro and promote the apoptosis and differentiation of tumor cells.