Cellular Physiology and Biochemistry (May 2015)

Identification and Characterization of Cancer Stem Cells from Head and Neck Squamous Cell Carcinoma Cell Lines

  • Valentina Pozzi,
  • Davide Sartini,
  • Romina Rocchetti,
  • Andrea Santarelli,
  • Corrado Rubini,
  • Stefano Morganti,
  • Rachela Giuliante,
  • Stefania Calabrese,
  • Giulia Di Ruscio,
  • Fiorenza Orlando,
  • Mauro Provinciali,
  • Franca Saccucci,
  • Lorenzo Lo Muzio,
  • Monica Emanuelli

DOI
https://doi.org/10.1159/000430138
Journal volume & issue
Vol. 36, no. 2
pp. 784 – 798

Abstract

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Background/Aims: Head and neck squamous cell carcinoma (HNSCC) ranks sixth worldwide for tumor-related mortality. A subpopulation of tumor cells, termed cancer stem cells (CSCs), has the ability to support cancer growth. Therefore, profiling CSC-enriched populations could be a reliable tool to study cancer biology. Methods: We performed phenotypic characterization of 7 HNSCC cell lines and evaluated the presence of CSCs. CSCs from Hep-2 cell line and HNSCC primary cultures were enriched through sphere formation and sphere-forming cells have been characterized both in vitro and in vivo. In addition, we investigated the expression levels of Nicotinamide N-methyltransferase (NNMT), an enzyme overexpressed in several malignancies. Results: CSC markers were markedly expressed in Hep-2 cell line, which was found to be highly tumorigenic. CSC-enriched populations displayed increased expression of CSC markers and a strong capability to form tumors in vivo. We also found an overexpression of CSC markers in tumor formed by CSC-enriched populations. Interestingly, NNMT levels were significantly higher in CSC-enriched populations compared with parental cells. Conclusion: Our study provides an useful procedure for CSC identification and enrichment in HNSCC. Moreover, results obtained seem to suggest that CSCs may represent a promising target for an anticancer therapy.

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