靶向蛋白酪氨酸磷酸酶1B小分子干扰RNA对结肠癌LoVo细胞增殖和成瘤能力的影响

Inhibition of colorectal carcinoma LoVo cell proliferation by small interfering RNA specific to PTP1B gene in vivo

目的:探讨沉默蛋白酪氨酸磷酸酶1B(PTP1B)基因的RNA干扰对人结肠癌LoVo细胞增殖和成瘤能力的影响。方法:应用小分子干扰RNA(siRNA)技术沉默PTP1B的表达(shRNA-PTP1B),采用逆转录聚合酶链反应和Western Blot分别在mRNA和蛋白水平检测抑制效果。CCK-8被用于检测沉默PTP1B表达对肿瘤细胞增殖的影响。在体外实验的基础上建立裸鼠模型,建立稳定表达干扰RNA细胞系,观察干扰RNA稳定表达对人结肠癌裸鼠移植成瘤的影响。结果:shRNA-PTP1B有效沉默LoVo细胞PTP1B mRNA及蛋白的表达,成功筛选shRNA-PTP1B稳定表达细胞株LoVo/shRNA细胞。在体外试验中与对照组比较LoVo/shRNA细胞的增殖能力明显下降。LoVo/shRNA细胞裸鼠移植成瘤体积,明显减小(P均<0.05)。结论:shRNA-PTP1B可以沉默人结肠癌PTP1B基因的表达,显著抑制LoVo细胞的增殖,降低LoVo细胞的成瘤能力。

Objective： To study the status of proliferation of colorectal carcinoma LoVo cell by using RNA interfer- ence technique to silence protein tyrosine phosphatase 1B （PTP1B） gene in vivo and explore whether PTP1B siRNA could become a promising tool in the treatment of colorectal carcinoma. Method： In vivo a stabilized cell strain expressing an ef- fective siRNA （LoVo/shRNA cell） was screened, and the effect on growth inhibition and tumor formation of LoVo cells were observed. Result： shRNA-PTP1B showed a significant and effective inhibition of PTP1B in gene and protein expression, and G418 was successfully used to screen stable cell strains expressing shRNA FFP1B （LoVo/shRNA cell） and nonsense siRNA （LoVo/negative cell）. The growth curve of LoVo/shRNA cell strain rose more steadily than that of LoVo/negative cel did （P〈0.05）. In vivo, the volumes and weights of the tumors formed in a thymicmice with LoVo/shRNA cells significantly diminished, compared with the LoVo/negative group（P〈0.05）. Conclusion： In vivo shRNA- PTPIB can effectively trigger a post transcriptional PTP1B in gene silencing, significantly suppress the proliferation of LoVo cells. The findings in our study provides a rational support for the development of siRNAs as a therapy for stomach cancer in humans.