肝再生磷酸酶-3和微小RNA17-92家族成员在结肠癌细胞中异常表达的意义

The significance of the aberrant expression of phosphatase of regenerating liver-3 and microRNA- 17-92 family in colon cancer cells

目的探讨肝再生磷酸酶-3（PRL-3）和微小RNA17-92（miR-17-92）家族成员在结肠癌中异常表达的意义。方法构建稳定转染PRL-3基因和空白对照质粒的结肠癌细胞株LoVo-PRL-3和LoVo-VC，用MicroRNA芯片筛查表达异常的促癌microRNA，从中选取miR-17-92家族成员miR-17、miR-19a行荧光实时定量聚合酶链反应（qRT-PCR）进行验证。在LoVo-PRL-3细胞中对STAT3信号传导与转录激活因子-3（STAT3）进行RNA干扰，检测miR-17、miR-19a的表达，在稳转细胞株中转染miR-17、miR-19a或对其进行敲除，用细胞计数试剂盒（CCK-8）、Tanswell试验对细胞增殖侵袭能力的变化进行研究。在13例患者结肠癌原发灶、转移灶及癌旁正常组织中行免疫组织化学及qRT-PCR检测PRL-3、pSTAT3和miR-17、miR-19a的表达。结果在结肠癌细胞株LoVo-PRL-3中miR-17、miR-19a的表达明显上调（P〈0．05），干扰STAT3可以抑制miR．17、miR-19a的表达。在LoVo-VC细胞中过表达miR-17、miR-19a促进了细胞的增殖（P〈0．05及P〈0．01）和侵袭（P〈0．01），而在LoVo-PRL-3细胞中敲除miR-17、miR-19a抑制了细胞的增殖侵袭（P〈0．05）。在结肠癌组织中PRL-3、pSTAT3和miR-17、miR-19a的表达呈正相关。结论PRL-3通过上调miR-17、miR-19a的表达在结肠癌细胞增殖侵袭中起到促进作用。

Objective To explore the significance of the aberrant expression phosphatase of regen- erating liver-3 （PRL-3） and microRNA （miR）-17-92 family in colon cancer cells. Methods We stablely transfected PRL-3 expressing plasmid and empty plasmid into LoVo colon cancer cells and established two cell lines： LoVo-PRL-3 and LoVo-VC. MicroRNA chipset was used to investigate the aberrant expression of some oncomiRs. Two important members of miR-17-92 family： miR-17 and miR-19a were selected, quanti- tative real-time reverse transcription-polymerase chain reaction （qRT-PCR） was used to validate the expression of miR-17 and miR-19a in LoVo cells. RNA interference was used to knocked down STAT3 in LoVo-PRL-3 cells, after that the expression miR-17 and miR-19a were detected. Transient transfection of miR-17 and miR-19a mimic into LoVo-VC cells or transient transfection of miR-17 and miR-19a inhibitor into LoVo-PRL-3 cells were performed to evaluate the proliferation and invasive ability of these cells by cell counting kit-8 （CCK-8） proliferating assay and Transwell chamber assay. In 13 paired primary colon canc- er tissues and metastatic lesions, immunohistochemistry was used to detect the expression of PRL-3 and pSTAT3 protein, while qRT-PCR was used to investigate the expression of PRL-3, miR-17 and miR-19a. Results In LoVo-PRL-3 cells, miR-17 and miR-19 were up-regulated significantly （P 〈 0.05 ）. Knockdown of STAT3 mRNA decreased the expression of miR-17 and miR-19. Over-expression of miR-17 and miR-19 promoted proliferation （P 〈0.05 and P 〈0. 01 ） and invasion （P 〈0. 01 ） of LoVo-VC celts,while knocking down of miR-17 and miR-19 inhibited proliferation and invasion of LoVo-PRL-3 cells （P 〈 0. 05）. PRL-3 was elevated in metastatic lesions of colon cancer and positively correlated with pSTAT3, miR-17 and miR-19a. Conclusion PRL-3 promotes proliferation and invasion of colon cancer cells by up-regulation of the expression of miR-17 and miR-19a.