RNA干扰对肾癌细胞端粒酶活性及增殖、凋亡的影响

目的 探讨针对人端粒酶RNA（hTR）及其催化亚基（hTERT）的小干扰RNA（siRNA）对肾癌细胞端粒酶活性及其增殖、凋亡的影响。方法 将hTR-siRNA、hTERT-siRNA（100nmol／L）单独或联合转染人肾癌786—0细胞，采用RT-PCR法检测hTR、hTERT mRNA表达，TRAP-ELISA法检测端粒酶活性，MTT法检测细胞增殖，免疫组化TUNEL法检测细胞凋亡。结果 （1）hTR-siRNA可显著降低786—0细胞hTR mRNA表达（P〈0．01），hTERT-siRNA可显著降低hTERT mRNA表达（P〈0．01），但彼此互不影响。（2）二者均能显著抑制端粒酶活性（P〈0．01，P〈0．01），并增加786—0细胞增殖抑制率及凋亡细胞阳性率（P〈0．01，P〈0．01）。二者联合应用与单独应用差异亦无显著性（P〉0．05）。结论 hTR、hTERT siRNA通过抑制各自基因表达，抑制人肾癌细胞端粒酶活性，进而抑制增殖、促进凋亡。

Inhibition of Telomerase Activity in Human Renal Carcinoma Cells by RNA Interference Leads to Inhibition of Proliferation and Induction of Apoptosis

Objective To evaluate the effects of small interfering RNA(siRNA)against either the template RNA (hTR) or its catalytic subunit (hTERT) of telomerase gene on the proliferation and apoptosis of human renal carcinoma cell line 786-0 cells.Methods 786-0 cells were transfected with hTR-siRNA or hTERT-siRNA (100nmol/L).The mRNA expression of hTR and hTERT was detected by RT-PCR.The telomerase activity was detected by telomeric repeat amplification protocol (TRAP).The proliferation of 786-0 cells was detected by MTT assay.The apoptosis of 786-0 cells was detected by TUNEL assay.Results The hTR and hTERT expression levels of 786-0 cells were reduced significantly by hTR-siRNA and hTERT-siRNA respectively.Both types of siRNA reduced telomerase activity,inhibited proliferation and increased apoptosis of 786-0 cells.When cells were treated with both hTR-siRNA and hTERT-siRNA simultaneously,the effects did not exceed that seen with each separately.Conclusion siRNA against hTR or hTERT gene can inhibit the proliferation and induce apoptosis by blocking telomerase activity of human renal carcinoma 786-0 cells.The inhibition of telomerase by siRNA may be a rational approach in gene therapy for renal cancer.