Chen Shi-Ming, Tao Ze-Zhang, Hua Qing-Quan, Liu Dan, Chi Hua-Ming, Cai Qing
Department of Otolaryngology-Head and Neck Surgery, Renmin Hospital of Wuhan University, Wuhan, China.
Arch Otolaryngol Head Neck Surg. 2006 Feb;132(2):200-5. doi: 10.1001/archotol.132.2.200.
Telomerase activity is mainly regulated by the human telomerase reverse transcriptase (hTERT) gene. Our objective was to investigate the effect of short hairpin RNA (shRNA) on hTERT expression and telomerase activity in laryngeal cancer cells.
Short hairpin RNA expression vectors targeting the messenger RNA of hTERT were constructed. Cells were treated with shRNA expression vectors directed against 2 different hTERT sites, control vectors that included mismatched shRNA and those without shRNA. The expression of hTERT was determined by reverse-transcriptase polymerase chain reaction and Western blotting. The activity of telomerase was measured by telomeric repeated amplification enzyme-linked immunosorbent assay. The cell viability was examined using the 3-(4,5-dimethyl thizol-2-yl) 2,5-diphenyl tetrazolium bromide assay.
We found that treatment of shRNA expression vectors induced a significant decrease in hTERT messenger RNA expression, the level of hTERT protein, telomerase activity, and cell viability. All of these effects were seen regardless of the target site, and the shRNA control showed none of these effects.
Our results suggest that shRNA directed against hTERT inhibits telomerase activity through suppression of the hTERT expression in laryngeal cancer cells and that RNA interfering technology may be a promising strategy for the treatment of laryngeal cancers.
端粒酶活性主要由人端粒酶逆转录酶(hTERT)基因调控。我们的目的是研究短发夹RNA(shRNA)对喉癌细胞中hTERT表达及端粒酶活性的影响。
构建靶向hTERT信使核糖核酸的短发夹RNA表达载体。用针对2个不同hTERT位点的shRNA表达载体、包含错配shRNA的对照载体以及无shRNA的对照载体处理细胞。通过逆转录聚合酶链反应和蛋白质免疫印迹法测定hTERT的表达。采用端粒重复序列扩增酶联免疫吸附测定法测量端粒酶的活性。使用3-(4,5-二甲基噻唑-2-基)-2,5-二苯基四氮唑溴盐法检测细胞活力。
我们发现,shRNA表达载体处理导致hTERT信使核糖核酸表达、hTERT蛋白水平、端粒酶活性及细胞活力显著降低。无论靶位点如何,所有这些效应均可见,而shRNA对照未显示这些效应。
我们的结果表明,针对hTERT的shRNA通过抑制喉癌细胞中hTERT的表达来抑制端粒酶活性,并且RNA干扰技术可能是治疗喉癌的一种有前景的策略。