title: Stem cell profiling in head and neck cancer reveals an Oct-4 expressing subpopulation with properties of chemoresistance.
abstract: OBJECTIVE
  In the past decade cancer, including head and neck squamous cell cancer (HNSCC), is increasingly being regarded as a stem cell associated disease which arises from cells with the property of stemness. According to the cancer stem cell (CSC) theory, only a specific subpopulation of cancer cells has the ability to initiate and perpetuate cancer growth, especially under treatment. In this article we describe a subpopulation of cells within HNSCC that expresses the stemness factor Oct-4, which leads to apoptotic resistance after exposure to chemotherapeutic agents.
  
  
  METHODS
  Permanent cell lines and HNSCC tissue were analyzed for expression of stem cell markers using flow cytometric, immunohistochemical approaches and an antibody based protein array. Chemotherapeutic agent-induced growth inhibition, also known as "enrichment", was determined by the colorimetric cell proliferation assay (MTT-based) and putative stem cell markers were investigated by flow cytometry.
  
  
  RESULTS
  Various potential CSC markers were identified in heterogenic expression profiles in permanent cell lines and solid tumors. Our data suggest the Oct-4A isoform as a marker of stemness in HNSCC and the enrichment of cancer stem-like cells by various chemotherapeutic agents was associated with a significantly higher expression of Oct-4.
  
  
  CONCLUSIONS
  This data suggests that many potential CSC markers are expressed on different expression levels in HNSCC. Among these markers Oct-4(A) plays a pivotal role in the detection of cancer cells with enhanced chemoresistance and provide evidence for the existence of cancer stem-like cells in HNSCC.
authors.affiliation: Departments of Otorhinolaryngology, University of Schleswig-Holstein, Lübeck, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Reers
authors.affiliation: Departments of Otorhinolaryngology, University of Schleswig-Holstein, Lübeck, Germany.
authors.forename: Ann-Christin
authors.initials: AC
authors.lastname: Pfannerstill
authors.affiliation: Departments of Otorhinolaryngology, University of Schleswig-Holstein, Lübeck, Germany.
authors.forename: Regina
authors.initials: R
authors.lastname: Maushagen
authors.affiliation: Departments of Otorhinolaryngology, University of Schleswig-Holstein, Lübeck, Germany.
authors.forename: Ralph
authors.initials: R
authors.lastname: Pries
authors.affiliation: Departments of Otorhinolaryngology, University of Schleswig-Holstein, Lübeck, Germany. Electronic address: Barbara.Wollenberg@uk-sh.de.
authors.forename: Barbara
authors.initials: B
authors.lastname: Wollenberg
mesh_terms: D014408:Biomarkers, Tumor / Q000378:metabolism*; D002294:Carcinoma, Squamous Cell / Q000378:metabolism*; D045744:Cell Line, Tumor; D003124:Colorimetry; D005434:Flow Cytometry; D006258:Head and Neck Neoplasms / Q000378:metabolism*; D006801:Humans; D014411:Neoplastic Stem Cells / Q000378:metabolism*; D050814:Octamer Transcription Factor-3 / Q000378:metabolism*; D040081:Protein Array Analysis
chemical_list: D014408:Biomarkers, Tumor; D050814:Octamer Transcription Factor-3
keywords: CD44; Cancer stem cells; GATA4; Goosecoid; HNF-3ß/FoxA2; HNSCC; Head and neck cancer; Oct-4; Oct-4A; Otx2; PDX-1/IPF1; Sox17; Stem cell profiling