抑制核小体结合蛋白对人膀胱癌细胞增殖的影响

Effects of inhibiting nucleosomal binding protein 1 on proliferation of human bladder cancer cells

目的探讨核小体结合蛋白(NSBP1)对人膀胱癌细胞增殖的影响。方法采用脂质体转染法将NSBP1基因转入膀胱癌EJ细胞系,分别通过CCK8、流式细胞仪、Real-Time PCR及West-ern blot法观察EJ细胞的增殖,细胞周期时相的分布、凋亡以及CyclinD1、CyclinB1、Bcl-2蛋白的表达。结果 Real-Time PCR及Western blot结果显示经转染后EJ细胞的NSBP1显著地受到抑制(P<0.01)。CCK8结果提示EJ细胞转染后随着时间的延长,抑制率越大(P<0.01)。流式细胞仪检测发现,经转染干预后EJ细胞G2期比例增加(P<0.01),而凋亡细胞并没有显著变化(P>0.05)。West-ern blot结果再次验证周期蛋白CyclinB1显著下调(P<0.05),而CyclinD1没有统计学意义(P>0.05),凋亡蛋白Bcl-2也没有统计学意义(P>0.05)。结论 NSBP1是通过调控周期蛋白CyclinB1进而阻断或延缓细胞周期,而非通过细胞凋亡抑制膀胱癌细胞增殖。NSBP1在膀胱癌细胞增殖中起着重要作用。

Objective To explore the influences of nucleosomal binding protein 1 （NSBP1） on proliferation of human bladder cancer cells. Methods By the induction of liposome, knockdown of NSBP1 by RNA interference vectors were transfected into bladder cancer cell line EJ. CCK8 （cell counting kit-8 ） , flow cytometry. Real-Time PCR and Western blot were used to observe the effects of NSBP1 on growth, proliferation, cell cycle, apoptosis and the protein expression of CyclinD1, CyclinB1 and Bcl-2 in EJ cells cultured in vitro. Results As detected by Western blot and Real-Time PCR, we found that NSBP1 was remarkably decreased by RNAi treatment （ P 〈 0. 01 ）. As detected by the CCK-8 assay, RNAi-induced NSBP1 deficiency inhibited EJ cell growth, arid the inhibition was dependent on time （ P 〈 0. 01 ）. Flow cytometry observed it also could increase the ratio of G2 （P 〈 0. 01 ） , while there was no significant increased apoptosis in NSBP1 transfected cells（ P 〉 0. 05 ）. Western blot showed the protein expression of CyelinB1 was reduccd（P 〈 0. 05）, and the protein expression of CyclinD1 and Bcl-2 were no significant change（ P 〉 0. 05 ）. Conclusions NSBP1 through the regulation of CyclinB1 to interrupt or delay the cell proliferation, rather than by apoptosis of bladder cancer cells. NSBP1 expression may play a positive role in the proliferation of bladder cancer cells.