S-M Zhu1, C-M Chen, Z-Y Jiang, B Yuan, M Ji, F-H Wu, J Jin. 1. Department of Surgery, Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Chongming Branch, Shanghai, China. jimin0518@126.com.
Abstract
OBJECTIVE: Epithelial-mesenchymal transition (EMT) plays an important role in the malignant transformation of cancer. MicroRNAs are a group of small non-coding RNA molecules that down-regulate the expression of genes involved in tumorigenesis. Although microRNA-185 (miR-185) participates in the pathogenesis of several types of cancer, its relationship with EMT in human hepatocellular carcinoma (HCC) has not been investigated. The present study aims to elucidate the regulatory effects of miR-185 on EMT in HCC cells. MATERIALS AND METHODS: MTT and an in vitro wound-healing assay were performed to determine cell growth and metastasis potential, respectively. Real-time PCR was used to measure the mRNA expression of miR-185 and Six2. In addition, protein expression levels of Six2 and EMT-related markers were determined by western blot. RESULTS: Our study showed that miR-185 was significantly down-regulated in HCC cells. Also, a luciferase reporter gene assay confirmed Six2 as a direct target of miR-185. Functional analyses indicated that miR-185 up-regulation remarkably suppressed cell growth and the metastatic potential of HCC cells. We also found that ectopic expression of miR-185 reversed EMT via the up-regulation of E-cadherin and down-regulation of vimentin in epithelial and mesenchymal HCC cells. CONCLUSIONS: miR-185 suppresses cell growth and EMT progression by targeting Six2, providing a novel target for the molecular treatment of liver malignancies.
OBJECTIVE: Epithelial-mesenchymal transition (EMT) plays an important role in the malignant transformation of cancer. MicroRNAs are a group of small non-coding RNA molecules that down-regulate the expression of genes involved in tumorigenesis. Although microRNA-185 (miR-185) participates in the pathogenesis of several types of cancer, its relationship with EMT in humanhepatocellular carcinoma (HCC) has not been investigated. The present study aims to elucidate the regulatory effects of miR-185 on EMT in HCC cells. MATERIALS AND METHODS:MTT and an in vitro wound-healing assay were performed to determine cell growth and metastasis potential, respectively. Real-time PCR was used to measure the mRNA expression of miR-185 and Six2. In addition, protein expression levels of Six2 and EMT-related markers were determined by western blot. RESULTS: Our study showed that miR-185 was significantly down-regulated in HCC cells. Also, a luciferase reporter gene assay confirmed Six2 as a direct target of miR-185. Functional analyses indicated that miR-185 up-regulation remarkably suppressed cell growth and the metastatic potential of HCC cells. We also found that ectopic expression of miR-185 reversed EMT via the up-regulation of E-cadherin and down-regulation of vimentin in epithelial and mesenchymal HCC cells. CONCLUSIONS:miR-185 suppresses cell growth and EMT progression by targeting Six2, providing a novel target for the molecular treatment of liver malignancies.