The Epstein-Barr virus-miRNA-BART6-5p regulates TGF-β/SMAD4 pathway to induce glycolysis and enhance proliferation and metastasis of gastric cancer cells

Oncol Res. 2024 Apr 23;32(5):999-1009. doi: 10.32604/or.2024.046679. eCollection 2024.

Abstract

Background: EBV-miR-BARTs exhibit significant relevance in epithelial tumors, particularly in EBV-associated gastric and nasopharyngeal cancers. However, their specific mechanisms in the initiation and progression of gastric cancer remain insufficiently explored.

Material and methods: Initially, EBV-miRNA-BART6-5p and its target gene SMAD4 expression were assessed in EBV-associated gastric cancer tissues and cell lines. Subsequent transfection induced overexpression of EBV-miRNA-BART6-5p in AGS and MKN-45, and downregulation in EBV-positive cells (SUN-719). The subsequent evaluation aimed to observe their impact on gastric cancer cell proliferation, migration, and glycolytic processes, with the TGF-β/SMAD4 signaling pathway value clarified using a TGF-β inhibitor.

Results: EBV-miRNA-BART6-5p exhibits pronounced upregulation in EBV-associated gastric cancer tissues and EBV-positive cells, while its target gene SMAD4 demonstrates downregulated expression. Upregulation of it can promote the proliferation and migration of gastric cancer cells. Additionally, We found EBV-miRNA-BART6-5p promotes glycolysis of gastric cancer cells. Inhibition of the TGF-β/SMAD4 signaling pathway resulted in suppressed proliferation and migration of gastric cancer cells, concomitant with a diminished glycolytic capacity.

Conclusion: In this study, we found that EBV-miRNA-BART6-5p can target SMAD4, effectively increasing glycolysis in gastric cancer cells by regulating the TGF-β/SMAD4 signaling pathway, thereby enhancing the proliferation and metastasis of gastric cancer cells. Our findings may offer new insights into the metabolic aspects of gastric cancer.

Keywords: EBV; Gastric cancer; Glycolysis; TGF-β/SMAD4.

MeSH terms

  • Cell Line, Tumor
  • Cell Movement* / genetics
  • Cell Proliferation*
  • Epstein-Barr Virus Infections / complications
  • Epstein-Barr Virus Infections / genetics
  • Epstein-Barr Virus Infections / metabolism
  • Epstein-Barr Virus Infections / pathology
  • Epstein-Barr Virus Infections / virology
  • Gene Expression Regulation, Neoplastic*
  • Glycolysis* / genetics
  • Herpesvirus 4, Human* / genetics
  • Humans
  • MicroRNAs* / genetics
  • Neoplasm Metastasis
  • RNA, Viral / genetics
  • Signal Transduction*
  • Smad4 Protein* / genetics
  • Smad4 Protein* / metabolism
  • Stomach Neoplasms* / genetics
  • Stomach Neoplasms* / metabolism
  • Stomach Neoplasms* / pathology
  • Stomach Neoplasms* / virology
  • Transforming Growth Factor beta* / genetics
  • Transforming Growth Factor beta* / metabolism

Substances

  • Smad4 Protein
  • MicroRNAs
  • SMAD4 protein, human
  • Transforming Growth Factor beta
  • RNA, Viral