Neogenin-1 Promotes Cell Proliferation, Motility, and Adhesion by Up-Regulation of Zinc Finger E-Box Binding Homeobox 1 Via Activating the Rac1/PI3K/AKT Pathway in Gastric Cancer Cells

Cell Physiol Biochem. 2018;48(4):1457-1467. doi: 10.1159/000492255. Epub 2018 Jul 31.

Abstract

Background/aims: Neogenin-1 (Neo1) has been reported to be involved in diverse physiology and pathology functions, including cell proliferation, differentiation and migration. The present study aimed to explore the functional role of neogenin-1 (Neo1) in gastric cancer (GC), together with underlying mechanisms.

Methods: Neo1 expression was analyzed by qRT-PCR and Western blot analysis in both human GC cell lines and normal gastric epithelial cell line. Neo1 was respectively overexpressed or silenced by transfection with pcDNA3.1 or siRNA, and then the cells were incubated with or without different concentrations of cisplatin, transforming growth factor (TGF)-β1, and/or inhibitors of Rac-1 and PI3K. Thereafter, cell viability, invasion, and adhesion were measured by CCK-8, wound healing and adhesion assays, respectively. The expression levels of key factors involved in epithelial mesenchymal transition (EMT) and the PI3K/AKT pathway were analyzed by Western blot analysis.

Results: The results showed that the Neo1 level was significantly increased in GC cell lines, with the highest level in SGC-7901 cells. Overexpression of Neo1 significantly reduced the GC cell sensitivity to cisplatin and increased the cell viability, motility and adhesion ability, and while silencing of Neo1 showed contrary results. Moreover, overexpression of Neo1 dramatically downregulated the E-Cadherin level and upregulated the levels of N-Cadherin and Vimentin. In addition, the data revealed that Neo1 positively regulated the expression of Zinc finger E-box-binding homeobox 1 (ZEB1) by activating the Rac1/PI3K/AKT pathway.

Conclusions: Neo1 could promote cell proliferation, motility, and adhesion by up-regulation of ZEB1 via activating the Rac1/PI3K/AKT pathway in GC cells.

Keywords: Epithelial mesenchymal transition; Gastric cancer; Neogenin-1; Rac1/PI3K/AKT; Zinc finger E-box-binding homeobox 1.

MeSH terms

  • Antineoplastic Agents / pharmacology
  • Cadherins / genetics
  • Cadherins / metabolism
  • Cell Adhesion / drug effects
  • Cell Line, Tumor
  • Cell Movement / drug effects
  • Cell Proliferation* / drug effects
  • Cisplatin / pharmacology
  • Epithelial-Mesenchymal Transition / drug effects
  • Humans
  • Nerve Tissue Proteins / antagonists & inhibitors
  • Nerve Tissue Proteins / genetics
  • Nerve Tissue Proteins / metabolism*
  • Phosphatidylinositol 3-Kinases / metabolism
  • Proto-Oncogene Proteins c-akt / metabolism
  • RNA Interference
  • RNA, Small Interfering / metabolism
  • Receptors, Cell Surface / antagonists & inhibitors
  • Receptors, Cell Surface / genetics
  • Receptors, Cell Surface / metabolism*
  • Signal Transduction* / drug effects
  • Stomach Neoplasms / metabolism
  • Stomach Neoplasms / pathology
  • Up-Regulation / drug effects
  • Vimentin / genetics
  • Vimentin / metabolism
  • Zinc Finger E-box-Binding Homeobox 1 / genetics
  • Zinc Finger E-box-Binding Homeobox 1 / metabolism*
  • rac1 GTP-Binding Protein / metabolism

Substances

  • Antineoplastic Agents
  • Cadherins
  • NEO1 protein, human
  • Nerve Tissue Proteins
  • RNA, Small Interfering
  • Receptors, Cell Surface
  • Vimentin
  • Zinc Finger E-box-Binding Homeobox 1
  • Proto-Oncogene Proteins c-akt
  • rac1 GTP-Binding Protein
  • Cisplatin