Silencing IGF-II impairs C-myc and N-ras expressions of SMMC-7721 cells via suppressing FAK/PI3K/Akt signaling pathway

Cytokine. 2017 Feb:90:44-53. doi: 10.1016/j.cyto.2016.10.008. Epub 2016 Oct 18.

Abstract

Emerging evidence confirms that insulin-like growth factor -II (IGF-II), oncogenes C-myc and N-ras are an essential regulator for development and growth in hepatocellular carcinoma (HCC). Although our previous study also indicated that IGF-II might upregulate levels of oncogenes C-myc and N-ras in hepatoma carcinoma cells, the molecular mechanism had not been fully elucidated. Herein, we successfully silenced IGF-II expression in SMCC-7721 cells by small RNA interference. Functional analysis showed that knockdown of IGF-II significantly suppressed growth and proliferation of SMMC-7721 cells and decreased C-myc and N-ras mRNA and protein levels. And this function was mediated by the FAK/PI3K/Akt signaling pathway. Taken together, IGF-II siRNA inactivates the FAK/PI3K/Akt signaling pathway, and further reduces cell proliferation, N-ras and C-myc levels in SMMC-7721 cells. Especially, understanding the relationship between IGF-II and oncogenes N-ras and C-myc in cancer cells will provide novel clues for clinic HCC treatment in the future.

Keywords: C-myc; Hepatocellular carcinoma (HCC); Insulin-like growth factor -II (IGF-II); N-ras; Proliferation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Line, Tumor
  • Focal Adhesion Kinase 1 / genetics
  • Focal Adhesion Kinase 1 / metabolism*
  • GTP Phosphohydrolases / genetics
  • GTP Phosphohydrolases / metabolism*
  • Gene Expression Regulation
  • Humans
  • Insulin-Like Growth Factor II / genetics
  • Insulin-Like Growth Factor II / metabolism*
  • Membrane Proteins / genetics
  • Membrane Proteins / metabolism*
  • Phosphatidylinositol 3-Kinases / genetics
  • Phosphatidylinositol 3-Kinases / metabolism*
  • Proto-Oncogene Proteins c-akt / genetics
  • Proto-Oncogene Proteins c-akt / metabolism*
  • Proto-Oncogene Proteins c-myc / genetics
  • Proto-Oncogene Proteins c-myc / metabolism*
  • Signal Transduction*

Substances

  • IGF2 protein, human
  • MYC protein, human
  • Membrane Proteins
  • Proto-Oncogene Proteins c-myc
  • Insulin-Like Growth Factor II
  • Phosphatidylinositol 3-Kinases
  • Focal Adhesion Kinase 1
  • PTK2 protein, human
  • Proto-Oncogene Proteins c-akt
  • GTP Phosphohydrolases
  • NRAS protein, human