Knockdown of FRAT1 inhibits hypoxia-induced epithelial-to-mesenchymal transition via suppression of the Wnt/β-catenin pathway in hepatocellular carcinoma cells

Oncol Rep. 2016 Nov;36(5):2999-3004. doi: 10.3892/or.2016.5130. Epub 2016 Sep 23.

Abstract

Hypoxia-induced epithelial-to-mesenchymal transition (EMT) in hepatocellular carcinoma (HCC) was investigated. Frequently rearranged in advanced T-cell lymphomas-1 (FRAT1) is a positive regulator of the Wnt/β-catenin signaling pathway and is overexpressed in many human tumors. However, the expression and role of FRAT1 in HCC has not been elucidated. In this study, we investigated the effect of FRAT1 on EMT process in HCC cells induced by hypoxia. Our results showed that FRAT1 is highly expressed in HCC tissues and cell lines. Hypoxia significantly induced FRAT1 expression in HCC cells. FRAT1 knockdown inhibited hypoxia-induced cell migration/invasion, downregulation of epithelial markers and upregulation of mesenchymal markers. Moreover, FRAT1 knockdown suppressed the expression levels of β-catenin, cyclin D1 and c-myc in HCC cells under the same hypoxic condition. Our results revealed that FRAT1 is a hypoxia factor that is critical for the induction of EMT in HCC cells. These data suggest a potential role for targeting FRAT1 in the prevention of hypoxia-induced HCC cancer progression and metastasis mediated by EMT.

MeSH terms

  • Adaptor Proteins, Signal Transducing
  • Carcinoma, Hepatocellular / genetics*
  • Carcinoma, Hepatocellular / pathology
  • Cell Line, Tumor
  • Cell Proliferation / genetics
  • Epithelial-Mesenchymal Transition / genetics
  • Gene Expression Regulation, Neoplastic
  • Humans
  • Intracellular Signaling Peptides and Proteins / genetics*
  • Liver Neoplasms / genetics*
  • Liver Neoplasms / pathology
  • Proto-Oncogene Proteins / genetics*
  • Tumor Hypoxia / genetics
  • Wnt Signaling Pathway / genetics
  • beta Catenin / biosynthesis
  • beta Catenin / genetics

Substances

  • Adaptor Proteins, Signal Transducing
  • FRAT1 protein, human
  • Intracellular Signaling Peptides and Proteins
  • Proto-Oncogene Proteins
  • beta Catenin