title: Distribution of circulating natural killer cells and T lymphocytes in head and neck squamous cell carcinoma.
abstract: OBJECTIVE
  Natural killer (NK) cells are capable of eliminating malignantly transformed cells without prior sensitization. In contrast to NK-cells, T lymphocytes possess antitumourous activity that is restricted to major histocompatibility complex (MHC) recognition. The aim of this study was to determine the causes of the different distributions of these cell types in the peripheral blood of patients with head and neck squamous cell carcinomas (HNSCC).
  
  
  METHODS
  A cohort of 105 subjects was divided into three clinical groups: non-treated HNSCC patients, treated relapse-free HNSCC patients and healthy control subjects. Peripheral blood mononuclear cells (PBMC) were isolated from venous blood, subsets were depleted, flow cytometric counts were made and subsequently correlation analyses with clinical parameters were performed.
  
  
  RESULTS
  Treated relapse-free HNSCC patients have a significantly increased mean proportion of NK-cells in PBMC of 26.39% (p<0.001), whereas T lymphocytes and natural killer-T-(NKT) cells of treated patients have a significantly decreased mean proportion in PBMC of 55.15% (p<0.05) at least 12 months after treatment. This inverse redistribution of these two subsets is reflected in a significantly increased mean NK/T-ratio of 0.54 (p<0.05) in treated patients. The NK/T-ratio correlates with the systemic invasiveness of the type of therapy patients undergo and is highest after surgery with adjuvant radiochemotherapy (0.64, rs=0.334, p<0.01). This appears to be a post-therapeutic long-term effect in treated patients, as they had a mean relapse-free period until venous puncture of 47.9 months in our study. We also demonstrated age-dependent changes in the peripheral distribution of T- and NK-cells.
  
  
  CONCLUSIONS
  These findings reveal new aspects in understanding tumour biology and interactions with the cellular immune system which provide novel starting points for further research.
authors: Department of Otorhinolaryngology, Head and Neck Surgery, University Medical Center Hamburg-Eppendorf, Hamburg, Germany. ar.boettcher@uke.de
authors: Arne
authors: A
authors: Böttcher
authors: Jürgen
authors: J
authors: Ostwald
authors: Ellen
authors: E
authors: Guder
authors: Hans Wilhelm
authors: HW
authors: Pau
authors: Burkhard
authors: B
authors: Kramp
authors: Steffen
authors: S
authors: Dommerich
mesh_terms: D000328:Adult; D000368:Aged; D002294:Carcinoma, Squamous Cell / Q000097:blood / Q000276:immunology* / Q000628:therapy; D016022:Case-Control Studies; D015331:Cohort Studies; D005260:Female; D005434:Flow Cytometry; D006258:Head and Neck Neoplasms / Q000097:blood / Q000276:immunology* / Q000628:therapy; D006801:Humans; D007694:Killer Cells, Natural / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D055611:Natural Killer T-Cells / Q000276:immunology*; D000077195:Squamous Cell Carcinoma of Head and Neck