title: Suppression of natural killer-cell and dendritic-cell apoptotic tumoricidal activity in patients with head and neck cancer.
abstract: BACKGROUND
  Natural killer (NK) cells and dendritic cells (DCs) mediate tumor cell apoptosis using tumor necrosis factor superfamily ligands (TNFSFLs). This cytotoxicity is an important anticancer immune defense mechanism.
  
  
  METHODS
  We examined TNFSFL expression and apoptotic tumoricidal activity (ATA) of purified NK cells and DCs, and peripheral blood mononuclear leukocytes (PBMLs) of healthy individuals and patients with head and neck cancer (HNC) before and after cancer ablation.
  
  
  RESULTS
  PBMLs, NK cells and DCs, but not NK-cell/DC-depleted PBMLs, expressed multiple TNFSFLs and mediated ATA. Both TNFSFL expression and ATA were suppressed in tumor-bearing, and restored in tumor-ablated patients with (HNC) Soluble TNF superfamily receptors (solTNFSFRs) were increasingly bound by PBNLs of tumor-bearing HNC patients. Dissociation of solTNFSFR led to more pronounced increases in TNFSFL expression and ATA of PBMLs of patients with HNC than healthy individuals.
  
  
  CONCLUSIONS
  NK-cell and DC TNFSFL expression and ATA are suppressed in patients with HNC. This suppression is tumor-dependent and possibly mediated by solTNFSFRs.
authors.affiliation: Department of Pathology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.
authors.forename: Dejan
authors.initials: D
authors.lastname: Baskic
authors.forename: Lazar
authors.initials: L
authors.lastname: Vujanovic
authors.forename: Nebojsa
authors.initials: N
authors.lastname: Arsenijevic
authors.forename: Theresa L
authors.initials: TL
authors.lastname: Whiteside
authors.forename: Eugene N
authors.initials: EN
authors.lastname: Myers
authors.forename: Nikola L
authors.initials: NL
authors.lastname: Vujanovic
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017209:Apoptosis / Q000276:immunology*; D045744:Cell Line, Tumor; D003601:Cytotoxicity Tests, Immunologic; D003713:Dendritic Cells / Q000276:immunology*; D005260:Female; D005434:Flow Cytometry; D006258:Head and Neck Neoplasms / Q000276:immunology*; D006801:Humans; D007108:Immune Tolerance; D007694:Killer Cells, Natural / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D048069:Tumor Necrosis Factors / Q000276:immunology*; D055815:Young Adult
chemical_list: D048069:Tumor Necrosis Factors