转酮酶样蛋白1在人类鼻咽癌细胞生长增殖中的作用

目的:探讨转酮酶样蛋白1(TKTL1)在体外培养的人类鼻咽癌细胞生长增殖中的作用.方法:构建针对TKTL1 mRNA 的干扰RNA质粒,转染人类鼻咽癌细胞(CNE细胞系);检测转染前后CNE细胞中转酮酶活性的变化;实时定量RT-PCR检测转染前后CNE细胞转酮酶基因家族(TKT、TKTL1、TKTL2)mRNA表达水平的变化;通过流式细胞术和MTT实验检测转染前后CNE细胞增殖和细胞周期的改变.结果:实验组CNE细胞中转酮酶活性(携带有pEGFP-C1-U6/TKTL1)明显低于质粒对照组(携带有pEGFP-C1-U6/UC)和空白对照组(未转染细胞);实时定量RT-PCR结果显示转染前后CNE细胞中TKT和TKTL2 mRNA的表达水平均无显著差异.然而,实验组细胞中TKTL1的表达水平明显低于对照组,且实验组CNE细胞增殖明显被抑制,癌细胞被阻滞在G0/G1期.结论:转酮酶蛋白TKTL1在人类鼻咽癌细胞的生长增殖中起重要作用,TKTL1可能成为肿瘤治疗研究的新靶点.

Effect of transketolase-like protein 1 on proliferation of human nasopharyngeal carcinoma cells

AIM:To investigate the effect of transketolase-like protein 1 (TKTL1) on proliferation of human nasopharyngeal carcinoma cells in vitro.METHODS:The siRNA against TKTL1 mRNA was constructed and transfected into human nasopharyngeal carcinoma cells (CNE cell line).The activity of transketolase was detected before and after RNA interference.Real-time PCR was used to determine the mRNA expression of transketolase (TKT) gene family in the CNE cells.Flow cytometry and MTT test were used to detect the effect of anti-TKTL1 siRNA on cell proliferation and cell cycle in the CNE cells.RESULTS:The total transketolase activity was significantly decreased in the CNE cells transfected with siRNA TKTL1 construct compared with the cells transfected with control vector or untransfected CNE cells.No significant difference in the expression level of TKT and TKTL2 gene between the CNE cells transfected with siRNA TKTL1 construct and the cells transfected with control vector or untransfected CNE cells was observed (P>0.05).However, the expression level of TKTL1 gene was significantly downregulated in the CNE cells transfected with siRNA TKTL1 construct compared with the cells transfected with control vector.Cancer cells were arrested in G0/G1 phase, and cancer cell proliferation was significantly inhibited in the CNE cells transfected with siRNA TKTL1 construct.CONCLUSION:TKTL1 plays an important role in the total transketolase activity and cell proliferation of human nasopharyngeal carcinoma.TKTL1 may be considered as a potential target for novel anti-cancer therapy.