Nicotine promotes acquisition of stem cell and epithelial-to-mesenchymal properties in head and neck squamous cell carcinoma

PLoS One. 2012;7(12):e51967. doi: 10.1371/journal.pone.0051967. Epub 2012 Dec 26.

Abstract

The ability of nicotine to enhance the malignancy of cancer cells is known; however, the possibility that nicotine could regulate a cancer stem cell phenotype remains to be well-established. In this study we sought to determine whether long-term exposure to nicotine could promote cancer stem cell-like properties in two head and neck squamous cell carcinoma cell lines, UMSCC-10B and HN-1. Nicotine treatment induced epithelial-to-mesenchymal transition (EMT) in both cell lines by repressing E-cadherin expression, and led to the induction of stem cell markers Oct-4, Nanog, CD44 and BMI-1, which was reversed upon ectopic re-expression of E-cadherin. Nicotine-treated cells formed spheres at a higher efficiency than non-treated cells, formed larger tumors when injected into mice, and formed tumors with 4-fold greater efficiency compared to control cells when injected at limiting doses. Consistent with previous literature, nicotine-treated cells demonstrated a greater capacity for survival and also a higher tendency to invade. Comparison of microRNA profiles between nicotine and control cells revealed the upregulation of miR-9, a repressor of E-cadherin, and the downregulation of miR-101, a repressor of EZH2. Taken together, these results suggest that nicotine may play a critical role in the development of tobacco-induced cancers by regulating cancer stem cell characteristics, and that these effects are likely mediated through EMT-promoting, microRNA-mediated pathways. Further characterization of such pathways remains a promising avenue for the understanding and treatment of tobacco-related cancers.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Apoptosis / drug effects
  • Biomarkers, Tumor / metabolism*
  • Blotting, Western
  • Cadherins / genetics
  • Cadherins / metabolism
  • Carcinoma, Squamous Cell / drug therapy
  • Carcinoma, Squamous Cell / metabolism
  • Carcinoma, Squamous Cell / pathology*
  • Cell Movement / drug effects*
  • Cell Proliferation / drug effects
  • Cells, Cultured
  • Epithelial-Mesenchymal Transition*
  • Fluorescent Antibody Technique
  • Gene Expression Profiling
  • Head and Neck Neoplasms / drug therapy
  • Head and Neck Neoplasms / metabolism
  • Head and Neck Neoplasms / pathology*
  • Humans
  • Immunoenzyme Techniques
  • Mice
  • Mice, SCID
  • MicroRNAs / genetics
  • Neoplastic Stem Cells / drug effects
  • Neoplastic Stem Cells / metabolism
  • Neoplastic Stem Cells / pathology*
  • Nicotine / pharmacology*
  • Nicotinic Agonists / pharmacology
  • Oligonucleotide Array Sequence Analysis
  • RNA, Messenger / genetics
  • Real-Time Polymerase Chain Reaction
  • Reverse Transcriptase Polymerase Chain Reaction

Substances

  • Biomarkers, Tumor
  • Cadherins
  • MicroRNAs
  • Nicotinic Agonists
  • RNA, Messenger
  • Nicotine

Grants and funding

This work was supported by the American Academy of Otolaryngology-Head and Neck Surgery Young Investigator Award (to WMO); ARMY/41482, Department of Defense/CDMRP (to WMO). The corresponding author had full access to all the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.