Nuclear Receptor Expression and Function in Human Lung Cancer Pathogenesis

PLoS One. 2015 Aug 5;10(8):e0134842. doi: 10.1371/journal.pone.0134842. eCollection 2015.

Abstract

Lung cancer is caused by combinations of diverse genetic mutations. Here, to understand the relevance of nuclear receptors (NRs) in the oncogene-associated lung cancer pathogenesis, we investigated the expression profile of the entire 48 NR members by using QPCR analysis in a panel of human bronchial epithelial cells (HBECs) that included precancerous and tumorigenic HBECs harboring oncogenic K-rasV12 and/or p53 alterations. The analysis of the profile revealed that oncogenic alterations accompanied transcriptional changes in the expression of 19 NRs in precancerous HBECs and 15 NRs according to the malignant progression of HBECs. Amongst these, peroxisome proliferator-activated receptor gamma (PPARγ), a NR chosen as a proof-of-principle study, showed increased expression in precancerous HBECs, which was surprisingly reversed when these HBECs acquired full in vivo tumorigenicity. Notably, PPARγ activation by thiazolidinedione (TZD) treatment reversed the increased expression of pro-inflammatory cyclooxygenase 2 (COX2) in precancerous HBECs. In fully tumorigenic HBECs with inducible expression of PPARγ, TZD treatments inhibited tumor cell growth, clonogenecity, and cell migration in a PPARγ-sumoylation dependent manner. Mechanistically, the sumoylation of liganded-PPARγ decreased COX2 expression and increased 15-hydroxyprostaglandin dehydrogenase expression. This suggests that ligand-mediated sumoylation of PPARγ plays an important role in lung cancer pathogenesis by modulating prostaglandin metabolism.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bronchi / cytology
  • Cell Line, Transformed
  • Cell Movement / drug effects
  • Cell Movement / genetics
  • Cell Proliferation / drug effects
  • Cell Proliferation / genetics
  • Cell Transformation, Neoplastic / genetics*
  • Cell Transformation, Neoplastic / metabolism
  • Cells, Cultured
  • Cyclooxygenase 2 / genetics
  • Cyclooxygenase 2 / metabolism
  • Epithelial Cells / metabolism*
  • Gene Expression Profiling / methods*
  • HEK293 Cells
  • Humans
  • Immunoblotting
  • Lung Neoplasms / genetics*
  • Lung Neoplasms / metabolism
  • Mutation
  • PPAR gamma / genetics
  • PPAR gamma / metabolism
  • Receptors, Cytoplasmic and Nuclear / genetics*
  • Receptors, Cytoplasmic and Nuclear / metabolism
  • Reverse Transcriptase Polymerase Chain Reaction
  • Sumoylation
  • Thiazolidinediones / pharmacology

Substances

  • PPAR gamma
  • Receptors, Cytoplasmic and Nuclear
  • Thiazolidinediones
  • 2,4-thiazolidinedione
  • Cyclooxygenase 2

Grants and funding

The National Research Foundation of Korea funded by the Ministry of Education, Science and Technology (NRF-2013R1A1A1A05005075 to YJ). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.