Overexpression of laminin-5 gamma-2 promotes tumorigenesis of pancreatic ductal adenocarcinoma through EGFR/ERK1/2/AKT/mTOR cascade

Cell Mol Life Sci. 2022 Jun 14;79(7):362. doi: 10.1007/s00018-022-04392-1.

Abstract

Pancreatic ductal adenocarcinoma (PDAC) is correlated with poor outcomes because of limited therapeutic options. Laminin-5 gamma-2 (LAMC2) plays a critical role in key biological processes. However, the detailed molecular mechanism and potential roles of LAMC2 in PDAC stay unexplored. The present study examines the essential role and molecular mechanisms of LAMC2 in the tumorigenesis of PDAC. Here, we identified that LAMC2 is significantly upregulated in microarray cohorts and TCGA RNA sequencing data of PDAC patients compared to non-cancerous/normal tissues. Patients with higher transcript levels of LAMC2 were correlated with clinical stages; dismal overall, as well as, disease-free survival. Additionally, we confirmed significant upregulation of LAMC2 in a panel of PDAC cell lines and PDAC tumor specimens in contrast to normal pancreatic tissues and cells. Inhibition of LAMC2 significantly decreased cell growth, clonogenic ability, migration and invasion of PDAC cells, and tumor growth in the PDAC xenograft model. Mechanistically, silencing of LAMC2 suppressed expression of ZEB1, SNAIL, N-cadherin (CDH2), vimentin (VIM), and induced E-cadherin (CDH1) expression leading to a reversal of mesenchymal to an epithelial phenotype. Interestingly, co-immunoprecipitation experiments demonstrated LAMC2 interaction with epidermal growth factor receptor (EGFR). Further, stable knockdown of LAMC2 inhibited phosphorylation of EGFR, ERK1/2, AKT, mTOR, and P70S6 kinase signaling cascade in PDAC cells. Altogether, our findings suggest that silencing of LAMC2 inhibited PDAC tumorigenesis and metastasis through repression of epithelial-mesenchymal transition and modulation of EGFR/ERK1/2/AKT/mTOR axis and could be a potential diagnostic, prognostic, and therapeutic target for PDAC.

Keywords: AKT; EGFR; Epithelial-mesenchymal transition; LAMC2; Migration; Pancreatic carcinoma; Xenograft model; mTOR.

MeSH terms

  • Carcinogenesis / genetics
  • Carcinoma, Pancreatic Ductal* / genetics
  • Carcinoma, Pancreatic Ductal* / metabolism
  • Carcinoma, Pancreatic Ductal* / pathology
  • Cell Adhesion Molecules
  • Cell Line, Tumor
  • Cell Movement / genetics
  • Cell Proliferation / genetics
  • Epithelial-Mesenchymal Transition / genetics
  • ErbB Receptors / genetics
  • ErbB Receptors / metabolism
  • Humans
  • Laminin* / biosynthesis
  • Laminin* / genetics
  • Laminin* / metabolism
  • MAP Kinase Signaling System*
  • Pancreatic Neoplasms* / genetics
  • Pancreatic Neoplasms* / metabolism
  • Pancreatic Neoplasms* / pathology
  • Proto-Oncogene Proteins c-akt* / genetics
  • Proto-Oncogene Proteins c-akt* / metabolism
  • TOR Serine-Threonine Kinases* / genetics
  • TOR Serine-Threonine Kinases* / metabolism

Substances

  • Cell Adhesion Molecules
  • LAMC2 protein, human
  • Laminin
  • MTOR protein, human
  • EGFR protein, human
  • ErbB Receptors
  • Proto-Oncogene Proteins c-akt
  • TOR Serine-Threonine Kinases