短发夹状RNA干扰对子宫颈癌细胞中Pin1基因表达及细胞增殖和凋亡的影响

目的研究短发夹状RNA(shRNA)干扰对宫颈癌细胞中Pin1基因表达及细胞增殖和凋亡的影响。方法构建靶向Pin1基因的shRNA真核表达质粒pSIREN-Pin1,在脂质体介导下转染人宫颈癌细胞系HeLa细胞(HeLa/p-shRNA组),同时以对照质粒pSIREN-Con(HeLa/p-Con组)和无血清培养基转染HeLa细胞(HeLa组)作为对照,分别应用RT-PCR技术及蛋白印迹法检测Pin1mRNA及蛋白表达水平,四甲基偶氮唑蓝(MTT)比色法和软琼脂细胞克隆实验检测细胞增殖状况,流式细胞仪分析细胞凋亡情况。结果转染后48h,HeLa/p-shRNA组Pin1mRNA及蛋白表达水平分别为0·19±0·05和0·33±0·14,HeLa/p-Con组分别为0·84±0·16和0·79±0·17,HeLa组分别为0·89±0·11和0·81±0·15,前组Pin1mRNA及蛋白表达水平分别与后两组比较,差异均有统计学意义(P<0·05);转染pSIREN-Pin1质粒后HeLa细胞中Pin1mRNA及蛋白表达抑制率分别为77%和58%。MTT比色法检测显示,HeLa/p-shRNA组细胞增殖率明显下降(P<0·05)。软琼脂克隆实验显示,HeLa/p-shRNA组细胞克隆小而稀疏,细胞克隆形成率为(12±3)%,明显低于HeLa/p-Con组的(20±5)%和HeLa组的(24±4)%(P<0·05)。流式细胞仪分析显示,HeLa/p-shRNA组细胞凋亡率为(24·3±5·7)%,明显高于HeLa/p-Con组的(5·0±1·4)%和HeLa组的(1·8±0·4)%(P<0·05)。结论shRNA干扰技术能有效抑制靶基因Pin1的表达,进而可抑制宫颈癌细胞增殖并诱导细胞凋亡增加,为宫颈癌的基因研究及治疗提供新思路。

Short hairpin RNA silences Pin1 and affects proliferation and apoptosis in HeLa cell line

OBJECTIVE: To study the effect of short hairpin RNA (shRNA) on the expression of Pin1 mRNA and protein and its influence on the proliferation and apoptosis in HeLa cell lines. METHODS: The recombinant plasmid pSIREN-Pin1 expressing Pin1-targeted shRNA was constructed and then transfected into cervical cancer cell lines by lipofectamine (HeLa/p-shRNA), the control vector pSIREN-Con (HeLa/p-Con) and culture media (HeLa) as control, respectively. The Pin1 mRNA and protein expression were detected by RT-PCR and immunoblotting. The proliferation of cells after transfection was detected by methyl thiazolyl tetrazolium (MTT) and colony formation in soft agar. Flow cytometry (FCM) was used to test the apoptosis of cells marked with fluorescein isothiocyanate (FITC)-annexin V. RESULTS: After transfected with pSIREN-Pin1 for 48 h, the expression of Pin1 mRNA and protein in HeLa cells were 0.19 +/- 0.05 and 0.33 +/- 0.14 respectively. Compared with HeLa/p-Con cells (0.84 +/- 0.16, 0.79 +/- 0.17) and HeLa cells (0.89 +/- 0.11, 0.81 +/- 0.15), the difference was significant respectively (P < 0.05). The proliferation was suppressed significantly in HeLa/p-shRNA cells. The colony ratios are as follows: HeLa/p-shRNA, (12 +/- 3)%; HeLa/p-Con, (20 +/- 5)%; HeLa, (24 +/- 4)% (P < 0.05). The apoptosis ratio was (24.3 +/- 5.7)% in HeLa/p-shRNA cells. It was significantly higher than that in HeLa/p-Con cells (5.0 +/- 1.4)% and HeLa cells (1.8 +/- 0.4)% (P < 0.05). CONCLUSIONS: RNA interference through Pin1-targeted shRNA can effectively inhibit the expression of target gene, and might be potentially useful in gene therapy of Pin1 related cervical cancers. Silencing Pin1 gene can suppress the proliferation and promote the apoptosis in HeLa cells.