Nicotine activates YAP1 through nAChRs mediated signaling in esophageal squamous cell cancer (ESCC)

PLoS One. 2014 Mar 12;9(3):e90836. doi: 10.1371/journal.pone.0090836. eCollection 2014.

Abstract

Cigarette smoking is an established risk factor for esophageal cancers. Yes-associated protein 1 (YAP1), the key transcription factor of the mammalian Hippo pathway, has been reported to be an oncogenic factor for many cancers. In this study, we find nicotine administration can induce nuclear translocation and activation of YAP1 in ESCC. Consistently, we observed nuclear translocation and activation of YAP1 by knockdown of CHRNA3, which is a negative regulator of nicotine signaling in bronchial and esophageal cancer cells. Nicotine administration or CHRNA3 depletion substantially increased proliferation and migration in esophageal cancer cells. Interestingly, we find that YAP1 physically interacts with nAChRs, and nAChRs-signaling dissociates YAP1 from its negative regulatory complex composed with α-catenin, β-catenin and 14-3-3 in the cytoplasm, leading to upregulation and nuclear translocation of YAP1. This process likely requires PKC activation, as PKC specific inhibitor Enzastaurin can block nicotine induced YAP1 activation. In addition, we find nicotine signaling also inhibits the interaction of YAP1 with P63, which contributes to the inhibitory effect of nicotine on apoptosis. Using immunohistochemistry analysis we observed upregulation of YAP1 in a significant portion of esophageal cancer samples. Consistently, we have found a significant association between YAP1 upregulation and cigarette smoking in the clinical esophageal cancer samples. Together, these findings suggest that the nicotine activated nAChRs signaling pathway which further activates YAP1 plays an important role in the development of esophageal cancer, and this mechanism may be of a general significance for the carcinogenesis of smoking related cancers.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Active Transport, Cell Nucleus / drug effects
  • Adaptor Proteins, Signal Transducing / metabolism*
  • Carcinoma, Squamous Cell / pathology*
  • Cell Line, Tumor
  • Cell Movement / drug effects
  • Cell Nucleus / drug effects
  • Cell Nucleus / metabolism
  • Cell Proliferation / drug effects
  • Esophageal Neoplasms / pathology*
  • Esophageal Squamous Cell Carcinoma
  • Gene Knockdown Techniques
  • Humans
  • Nicotine / pharmacology*
  • Phosphoproteins / metabolism*
  • Receptors, Nicotinic / deficiency
  • Receptors, Nicotinic / genetics
  • Receptors, Nicotinic / metabolism*
  • Signal Transduction / drug effects*
  • Transcription Factors
  • YAP-Signaling Proteins

Substances

  • Adaptor Proteins, Signal Transducing
  • Phosphoproteins
  • Receptors, Nicotinic
  • Transcription Factors
  • YAP-Signaling Proteins
  • YAP1 protein, human
  • nicotinic receptor subunit alpha3
  • Nicotine

Grants and funding

This study has been supported by the funds from the 973 National Key Fundamental Research Program of China (2009CB521801) and the National Natural Science Foundation of China (81021061). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.