端粒酶逆转录酶短发夹RNA对鼻咽癌细胞c-myc表达的影响

Influence of telomerase reverse transcriptase shRNA on expression of c-myc in nasopharyngea carcinoma cells

目的研究针对人端粒酶逆转录酶(humantelomerasereversetranscriptase,hTERT)的短发夹RNA(shorthairpinRNA,shRNA)对人鼻咽癌细胞系CNE端粒酶活性的抑制作用及对c-myc表达的影响。方法根据hTERTcDNA序列构建表达hTERT特异的、含荧光素基因的shRNA真核表达质粒shRNA1。将质粒shRNA1转染人CNE,MTT法测定细胞增殖,以TRAPPCR-ELISA法检测端粒酶活性,以蛋白印记法检测原癌基因蛋白质c-myc表达。结果质粒shRNA1及对照质粒shRNA2转染细胞后,大量细胞表达绿色荧光,其中shRNA1转染组见许多死亡细胞;与空白对照组比较,shRNA1转染组CNE端粒酶活性显著下降,部分细胞增殖受抑制,癌细胞1天、2天的c-myc表达水平均显著降低(P<0.01),分别下调约30.3%,31.2%。结论抑制CNE中端粒酶活性或hTERT基因表达将引起c-myc表达下调并进一步抑制细胞增殖。端粒酶与c-myc共同参与了CNE的发生、发展、增殖与分化的调控。

OBJECTIVE To investigate the influence of short hairpin RNA targeting human telomerase reverse transcriptase（hTERT）on inhibition of telomerase activity and on expression of protein c-myc in nasopharyngeal carcinoma cells. METHODS Plasmid shRNA1 containing fluorescein gene and hTERT cDNA sequences were synthesized. Cells were transfected with plasmid shRNA1. The cell viability was examined using the MTT assay. The activity of telomerase was tested by polymerase chain reaction telomeric repeat amplification protocolenzyme-linked immunosorbent assay （PCR-TRAPELISA）,protein c-myc expression was tested by western blot. RESULTS It was observed that treatment with pshRNA1 in the presence of a valid transfection reagent could significantly reduce telomerase activity and the expression of protein of c-myc. CONCLUSION Inhibition of telomerase activity or expression of hTERT mRNA in nasopharyngeal carcinoma cells could inhibit cells proliferation and reduce the expression of protein of c-myc.