Overexpression of Bmi‑1 promotes epithelial‑mesenchymal transition in CD133+Hep G2 cells

Mol Med Rep. 2017 Nov;16(5):6156-6161. doi: 10.3892/mmr.2017.7347. Epub 2017 Aug 24.

Abstract

Cancer stem cells (CSCs) and epithelial‑mesenchymal transition (EMT) are critical factors contributing to tumor metastasis and recurrence. The BMI1 proto‑oncogene (Bmi‑1) promotes the development and progression of hematologic malignancies and of several types of solid tumors. The aim of the present study was to explore the mechanism by which Bmi‑1 may promote invasion and migration of hepatocellular carcinoma Hep G2 cells. CD133 antigen is a transmembrane glycoprotein and regarded as a cancer stem cells marker in hepatocellular carcinoma. CD133+Hep G2 cells were enriched by magnetic‑activated cell sorting and exhibited greater viability compared with CD133‑Hep G2 cells, as measured by Cell Counting kit‑8 assay. Then, Bmi‑1 was overexpressed in CD133+Hep G2 cells by transfection with the Bmi‑1/pcDNA3.1(+) expression plasmid, and overexpression was confirmed by reverse‑transcription‑polymerase chain reaction and western blotting. Overexpression of Bmi‑1in CD133+Hep G2 cells resulted in the downregulation of E‑cadherin and upregulation of Vimentin at the protein level. The invasion and migration abilities of CD133+Hep G2 cells were increased in the Bmi‑1/pcDNA3.1(+)‑transfected group, as measured by Transwell invasion and wound healing assays, respectively. In conclusion, Bmi‑1 promoted invasion and migration of CD133+Hep G2 cells most likely through inducing EMT. The present findings may offer a potential novel target for the development of hepatocellular carcinoma therapies.

MeSH terms

  • AC133 Antigen / metabolism*
  • Cadherins / metabolism
  • Carcinoma, Hepatocellular / metabolism
  • Carcinoma, Hepatocellular / pathology
  • Cell Line, Tumor
  • Cell Movement / physiology
  • Down-Regulation / physiology
  • Epithelial-Mesenchymal Transition / physiology*
  • Hep G2 Cells
  • Humans
  • Liver Neoplasms / metabolism
  • Liver Neoplasms / pathology
  • Neoplastic Stem Cells / metabolism
  • Neoplastic Stem Cells / pathology
  • Polycomb Repressive Complex 1 / metabolism*
  • Up-Regulation / physiology
  • Vimentin / metabolism

Substances

  • AC133 Antigen
  • Bmi1 protein, rat
  • Cadherins
  • Prom1 protein, rat
  • Vimentin
  • Polycomb Repressive Complex 1