MicroRNA-195 Suppresses Angiogenesis and Metastasis of Hepatocellular Carcinoma by Inhibiting the Expression of VEGF, VAV2, and CDC42

Authors

  • Ruizhi Wang,

    1. Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, People's Republic of China
    Search for more papers by this author
  • Na Zhao,

    1. Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, People's Republic of China
    Search for more papers by this author
  • Siwen Li,

    1. Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, People's Republic of China
    Search for more papers by this author
  • Jian-Hong Fang,

    1. Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, People's Republic of China
    Search for more papers by this author
  • Mei-Xian Chen,

    1. Department of Hepatobiliary Oncology, Sun Yat-sen University, Guangzhou, People's Republic of China
    Search for more papers by this author
  • Jine Yang,

    1. Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, People's Republic of China
    Search for more papers by this author
  • Wei-Hua Jia,

    1. Bank of Tumor Resources, Cancer Center, Sun Yat-sen University, Guangzhou, People's Republic of China
    Search for more papers by this author
  • Yunfei Yuan,

    Corresponding author
    1. Department of Hepatobiliary Oncology, Sun Yat-sen University, Guangzhou, People's Republic of China
    • Address reprint requests to: Shi-Mei Zhuang, School of Life Sciences, Sun Yat-sen University, Xin Gang Xi Road 135#, Guangzhou 510275, People's Republic of China. E-mail: zhuangshimei@163.com or lsszsm@mail.sysu.edu.cn; fax: +86-20-84113469.

      Yunfei Yuan, Department of Hepatobiliary Oncology, Cancer Center, Sun Yat-sen University, Dongfengdong Road 651#, Guangzhou 510060, People's Republic of China. E-mail: yuanyf@mail.sysu.edu.cn; fax: +86-20-87343392.

    Search for more papers by this author
  • Shi-Mei Zhuang

    Corresponding author
    1. Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, People's Republic of China
    • Address reprint requests to: Shi-Mei Zhuang, School of Life Sciences, Sun Yat-sen University, Xin Gang Xi Road 135#, Guangzhou 510275, People's Republic of China. E-mail: zhuangshimei@163.com or lsszsm@mail.sysu.edu.cn; fax: +86-20-84113469.

      Yunfei Yuan, Department of Hepatobiliary Oncology, Cancer Center, Sun Yat-sen University, Dongfengdong Road 651#, Guangzhou 510060, People's Republic of China. E-mail: yuanyf@mail.sysu.edu.cn; fax: +86-20-87343392.

    Search for more papers by this author

  • Supported by grants from the Ministry of Science and Technology of China (2010CB912803, 2011CB811305, 2011ZX09307-001-04), the Ministry of Health of China (2012ZX10002011), the National Natural Science Foundation of China (30925036, 81230049), and the Fundamental Research Funds for the Central Universities (12lgjc03, 12lgpy25).

  • Potential conflict of interest: Nothing to report.

Abstract

Hepatocellular carcinoma (HCC) is characterized by active angiogenesis and metastasis, which account for rapid recurrence and poor survival. There is frequent down-regulation of miR-195 expression in HCC tissues. In this study, the role of miR-195 in HCC angiogenesis and metastasis was investigated with in vitro capillary tube formation and transwell assays, in vivo orthotopic xenograft mouse models, and human HCC specimens. Reduction of miR-195 in HCC tissues was significantly associated with increased angiogenesis, metastasis, and worse recurrence-free survival. Both gain-of-function and loss-of-function studies of in vitro models revealed that miR-195 not only suppressed the ability of HCC cells to promote the migration and capillary tube formation of endothelial cells but also directly repressed the abilities of HCC cells to migrate and invade extracellular matrix gel. Based on mouse models, we found that the induced expression of miR-195 dramatically reduced microvessel densities in xenograft tumors and repressed both intrahepatic and pulmonary metastasis. Subsequent investigations disclosed that miR-195 directly inhibited the expression of the proangiogenic factor vascular endothelial growth factor (VEGF) and the prometastatic factors VAV2 and CDC42. Knockdown of these target molecules of miR-195 phenocopied the effects of miR-195 restoration, whereas overexpression of these targets antagonized the function of miR-195. Furthermore, we revealed that miR-195 down-regulation resulted in enhanced VEGF levels in the tumor microenvironment, which subsequently activated VEGF receptor 2 signaling in endothelial cells and thereby promoted angiogenesis. Additionally, miR-195 down-regulation led to increases in VAV2 and CDC42 expression, which stimulated VAV2/Rac1/CDC42 signaling and lamellipodia formation and thereby facilitated the metastasis of HCC cells. Conclusion: miR-195 deregulation contributes to angiogenesis and metastasis in HCC. The restoration of miR-195 expression may be a promising strategy for HCC therapy. (Hepatology 2013;58:642-653)

Ancillary