Aberrant large tumor suppressor 2 (LATS2) gene expression correlates with EGFR mutation and survival in lung adenocarcinomas

Lung Cancer. 2014 Aug;85(2):282-92. doi: 10.1016/j.lungcan.2014.05.025. Epub 2014 Jun 16.

Abstract

Background: Large tumor suppressor 2 (LATS2) gene is a putative tumor suppressor gene with potential roles in regulation of cell proliferation and apoptosis in lung cancer. The aim of this study is to explore the association of aberrant LATS2 expression with EGFR mutation and survival in lung adenocarcinoma (AD), and the effects of LATS2 silencing in both lung AD cell lines.

Methods: LATS2 mRNA and protein expression in resected lung AD were correlated with demographic characteristics, EGFR mutation and survival. LATS2-specific siRNA was transfected into four EGFR wild-type (WT) and three EGFR mutant AD cell lines and the changes in LATS2 expression and relevant signaling molecules before and after LATS2 knockdown were assayed.

Results: Fifty resected lung AD were included (M:F=23:27, smokers:non-smokers=19:31, EGFR mutant:wild-type=21:29) with LATS2 mRNA levels showed no significant difference between gender, age, smoking and pathological stages while LATS2 immunohistochemical staining on an independent set of 79 lung AD showed similar trend. LATS2 mRNA level was found to be a significant independent predictor for survival status (disease-free survival RR=0.217; p=0.003; Overall survival RR=0.238; p=0.036). siRNA-mediated suppression of LATS2 expression resulted in augmentation of ERK phosphorylation in EGFR wild-type AD cell lines with high basal LATS2 expression, discriminatory modulation of Akt signaling between EGFR wild-type and mutant cells, and induction of p53 accumulation in AD cell lines with low baseline p53 levels.

Conclusions: LATS2 expression level is predictive of survival in patients with resected lung AD. LATS2 may modulate and contribute to tumor growth via different signaling pathways in EGFR mutant and wild-type tumors.

Keywords: EGFR signaling; Gene expression; Gene silencing; Large tumor suppressor 2 gene; Lung cancer.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenocarcinoma / genetics*
  • Adenocarcinoma / metabolism
  • Adenocarcinoma / mortality*
  • Adenocarcinoma / surgery
  • Adenocarcinoma of Lung
  • Adult
  • Aged
  • Aged, 80 and over
  • Cell Line, Tumor
  • DNA Mutational Analysis
  • ErbB Receptors / genetics*
  • ErbB Receptors / metabolism
  • Female
  • Gene Expression*
  • Gene Knockdown Techniques
  • Gene Silencing
  • Humans
  • Lung Neoplasms / genetics*
  • Lung Neoplasms / metabolism
  • Lung Neoplasms / mortality*
  • Lung Neoplasms / surgery
  • MAP Kinase Signaling System
  • Male
  • Middle Aged
  • Mutation*
  • Neoplasm Recurrence, Local
  • Neoplasm Staging
  • Prognosis
  • Protein Serine-Threonine Kinases / genetics*
  • Protein Serine-Threonine Kinases / metabolism
  • Proto-Oncogene Proteins c-akt / metabolism
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Risk Factors
  • Tumor Suppressor Protein p53 / metabolism
  • Tumor Suppressor Proteins / genetics*
  • Tumor Suppressor Proteins / metabolism

Substances

  • RNA, Messenger
  • Tumor Suppressor Protein p53
  • Tumor Suppressor Proteins
  • LATS2 protein, human
  • ErbB Receptors
  • Protein Serine-Threonine Kinases
  • Proto-Oncogene Proteins c-akt