Tang Hanqing, Li Keming, Zheng Jianyu, Dou Xibin, Zhao Yufeng, Wang Luyao
Department of Basic Medicine, Youjiang Medical University for Nationalities, Guangxi, China.
J Cell Biochem. 2019 May;120(5):8376-8384. doi: 10.1002/jcb.28122. Epub 2018 Nov 28.
It has been reported that microRNA-145 (miR-145) is downregulated in various cancers, including colorectal cancer (CRC). However, the role of miR-145 in progress of CRC and its mechanism remains unclear.
The expressions of miR-145 and tumor suppressor candidate 3 (TUSC3) were determined in CRC tissues and cells by real-time quantitative polymerase chain reaction and Western blot analysis. The effects of miR-145 and TUSC3 on cell viability, migration, and invasion of CRC cells were examined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-trtrazolium bromide assay and trans-well chamber experiment, respectively. The interaction between miR-145 and TUSC3 was explored by bioinformatics analysis, luciferase reporter assay, and Western blot analysis. The abundances of mitogen-activated protein kinase (MAPK) signaling pathway-related proteins were measured by Western blot analysis.
miR-145 expression was downregulated in CRC tissues and cell lines, and TUSC3 was upregulated in CRC tissues and correlated inversely with miR-145 abundance. Overexpression of miR-145 and knockdown of TUSC3 suppressed cell viability, migration, and invasion in LS174T and HCT116 cells. Moreover, TUSC3 was indicated as a novel target of miR-145 and its expression was negatively regulated by miR-145. Restoration of TUSC3 can partially reverse the inhibitory effects of miR-145 on phosphorylation of extracellular signal-regulated kinases 1 and 2 in CRC cells.
miR-145 can inhibit the viability, migration, and invasion through addressing MAPK signaling pathway by targeting TUSC3 in CRC cells, providing a novel biomarker for treatment of CRC.
据报道,微小RNA-145(miR-145)在包括结直肠癌(CRC)在内的多种癌症中表达下调。然而,miR-145在CRC进展中的作用及其机制仍不清楚。
通过实时定量聚合酶链反应和蛋白质印迹分析测定CRC组织和细胞中miR-145和肿瘤抑制候选基因3(TUSC3)的表达。分别采用3-(4,5-二甲基噻唑-2)-2,5-二苯基四氮唑溴盐法和Transwell小室实验检测miR-145和TUSC3对CRC细胞活力、迁移和侵袭的影响。通过生物信息学分析、荧光素酶报告基因检测和蛋白质印迹分析探索miR-145与TUSC3之间的相互作用。通过蛋白质印迹分析测定丝裂原活化蛋白激酶(MAPK)信号通路相关蛋白的丰度。
miR-145在CRC组织和细胞系中表达下调,TUSC3在CRC组织中上调,且与miR-145丰度呈负相关。miR-145的过表达和TUSC3的敲低抑制了LS174T和HCT116细胞的活力、迁移和侵袭。此外,TUSC3被确定为miR-145的一个新靶点,其表达受miR-145负调控。TUSC3的恢复可部分逆转miR-145对CRC细胞中细胞外信号调节激酶1和2磷酸化的抑制作用。
miR-145可通过靶向TUSC3调控MAPK信号通路来抑制CRC细胞的活力、迁移和侵袭,为CRC治疗提供了一种新的生物标志物。