Study on the relationship between TK gene regulated by enhanced suicide gene vector and telomerase activity in nasopharyngeal carcinoma cells
10.3969/j.issn.1001-1781.2010.04.009
- VernacularTitle:鼻咽癌细胞中增强型表达载体调控TK基因与端粒酶活性关系的研究
- Author:
Congxiang SHEN
;
Zhong WEN
;
Yuhong QIAN
;
Shaofeng MU
;
Xiaofang GUAN
- Publication Type:Journal Article
- Keywords:
nasopharyngeal neoplasms;
enhanced suicide gene vector;
TK gene;
telomerase
- From:
Journal of Clinical Otorhinolaryngology Head and Neck Surgery
2010;(4):168-173
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To explore the relationship between TK gene expression regulated by enhanced suicide gene vector and telomerase activity in nasopharyngeal carcinoma cells.Method:The reformed reconstructed enhanced vector, pGL3-basic-EGFP-TK-hTRETp-CMV enhancer, and hTERT mono-promoter vector, pGL3-basic-EGFP-TK-hTRETp(as controls), were transfected into telomerase(+) nasopharyngeal carcinoma 5-8F cell lines,telomerase(+) human breast cancer MCF-7 cell lines and telomerase(-) normal vascular endothelium cell lines respectively. TK gene green fluorescent protein was observed by fluorescence microscope. The expression of TK gene mRNA was measured by the real-time fluorescent quantified PCR and the telomerase activity was determined by the method of TRAP argentation in maligment tumour cells pre- and post-transfected by enhanced vector . Meanwhile the relationship beteewn TK and telomerase was analyzed.Result:①A strong TK gene fluorescent show and TK mRNA expression were displayed after the enhanced suicide gene vector was transfected into nasopharyngeal carcinoma 5-8F cell lines and human breast cancer MCF-7 cell line, which were more stronger than those of mono-promoter group,pGL3-basic-EGFP-TK-hTRETp,and ECV cells transfected by enhanced suicide gene vector. Meanwhile,real-time fluorescent quantified PCR showed that the A value of enhanced vector group was higher than that of controls. ②Telomerase activity after transfection of enhanced vector and GCV was lower than those before by the method of TRAP argentation in nasopharyngeal carcinoma cell lines,but no change in normal control cells after transfection of enhanced vector and GCV.③ After adding GCV, the obvious inhibitory effect of tumour cells growth induced by pGL3-basic-EGFP-TK-hTRETp-CMV enhancer were observed in nasopharyngeal carcinoma 5-8F cell lines and human breast cancer MCF-7 cell line, which was higher than those of mono-promoter, pGL3-basic-EGFP-TK-hTRETp,pGL3-basic-EGFP3 and blank controls, but without inhibitory effect in ECV cells transfected by enhanced vector. Conclusion:TK gene expression is regulated by hTERT promoter and CMV enhancer, and then the telomerase activity is reduced and the cancer cells are specifically killed.But it is unclear how the telomerase are down-regulated by TK gene.
