miR-598 对结直肠癌细胞转移潜能的影响

目的:探讨miR-598在结直肠癌转移中的作用和分子机制,为寻找新的结直肠癌治疗靶标提供理论依据。方法:收集30对人结直肠癌及癌旁正常组织标本,采用qRT-PCR检测miR-598的表达,采用Transwell和划痕实验确定miR-598对结直肠癌细胞侵袭和迁移能力的影响,利用在线靶基因预测软件,筛选出miR-598可能的下游靶基因Jagged 1(JAG1),利用Western blot及双荧光素酶报告基因实验检测miR-598对JAG1及上皮间质转化标志物(Vimentin及E-cadherin)表达的影响。结果:与正常肠黏膜组织对比,miR-598在结直肠癌组织中的表达水平明显降低;miR-598显著抑制结直肠癌细胞的侵袭及迁移能力;分子机制分析证实miR-598能够作用于JAG1的3'-UTR并抑制其表达;过表达miR-598显著下调Vimentin的表达水平,而提高E-cadherin的表达水平。结论:miR-598在人结直肠癌中表达明显下调;miR-598通过靶向调控靶基因JAG1的表达,抑制结直肠癌细胞EMT,从而有效的抑制了结直肠癌细胞的侵袭和迁移。

The Function of MiR-598 in Colorectal Cancer Metastasis

ABSTRACT Objective: To explore the regulatory role and the underlying mechanisms of miR-598 in human colorectal cancer (CRC) migration and invasion, laying a foundation for formulating novel therapeutic target for treatment of CRC. Methods: We detected miR-598 expression in 30 pairs of CRC tissues and paired adjacent normal tissues using qRT-PCR analysis; The effects of miR-598 on invasion and migration ability of CRC cells were determined using Transwell and Wound-healing assays when miR-598 were over-expressed and silenced. miRNA target analysis tools miRanda, TargetScan and DIANA-microT were used to explore potential target of miR-598; Jagged 1 (JAG1) was predicted to be a target of miR-598; The expression of JAG1 and epithelial mesenchymal transition (EMT) marks (Vimentin and E-cadherin) was detected by western blotting and luciferase reporter assay. Results: miR-598 expression was significantly lower in CRC tissues than that in normal mucosa; The ability of invasion and migration of CRC were decreased when miR-598 were over-expressed, and were enhanced when miR-598 were silenced; Biological information method predicted that JAG1 was a target of miR-598, and further showed that miR-598 can directly bind the 3''UTR of JAG1 by luciferase reporter assay. Western blot revealed that the expression of the JAG1 and Vimentin (one of EMT markers) were decreased after miR-598 over-expression, while E-cadherin which was another EMT marker was increased. MiR-598 inhibitor tood the opposite results. Conclusion: miR-598 was downregulated in CRC, and then inhibited the occurrence of EMT in CRC, which suppressed the ability of invasion and migration of CRC through negatively regulating JAG1 expression.