title: [Correlation of NK cell activity against autologous tumour cells and K562 cells with the clinical outcome during therapy with mistletoe extracts].
abstract: BACKGROUND
  Suppression of NK cell activity is considered to be an unfavourable prognostic factor for tumour progression. There is proof that mistletoe extracts may increase NK cell activity. However, the inverse relation between an increase of NK cell activity and clinical progress of cancer has not been investigated.
  
  
  OBJECTIVE
  The relation of NK cell activity and progress of cancer in patients under therapy with mistletoe extracts was examined in a prospective, monocentric, cohort study. At the same time the in vitro killing of K562 cells and autologous tumour cells was compared.
  
  
  METHODS
  40 patients with operable cancer of the breast or colon were included. The patients did not receive any immunologically relevant therapies except for mistletoe extracts. The absolute NK cell count in peripheral blood as well as the in vitro NK cell activity were monitored for up to 2 years and compared with clinical outcome as well as quality of life.
  
  
  RESULTS
  The absolute NK cell count in peripheral blood increased within the observation period. Patients without progression had a significantly higher mean activity of NK cells against K562 cells than patients with progression. In the latter group, only stage IV patients showed reduced NK cell activity. The killing activity against autologous tumour cells was <5% in about 77.5% of the patients and could not be evaluated further. The NK cell activity against K562 cells was not related to the number of NK cells.
  
  
  CONCLUSIONS
  We found a relation between NK cell activity and the progression of malignant disease. In further studies the causality of this relation has to be clarified. The establishment of NK cell activity against autologous tumour cells as a suitable parameter during follow-up was not successful.
authors.affiliation: Forschungsabteilung, Verein Filderklinik e.V., Filderstadt, Deutschland. schink@filderklinik.de
authors.forename: Michael
authors.initials: M
authors.lastname: Schink
authors.forename: Wilfried
authors.initials: W
authors.lastname: Tröger
authors.forename: Andreas
authors.initials: A
authors.lastname: Goyert
authors.forename: Heinz
authors.initials: H
authors.lastname: Scheuerecker
authors.forename: Hans-Konrad
authors.initials: HK
authors.lastname: Selbmann
authors.forename: Florian
authors.initials: F
authors.lastname: Glaser
mesh_terms: D000368:Aged; D001943:Breast Neoplasms / Q000188:drug therapy / Q000276:immunology*; D015331:Cohort Studies; D003110:Colonic Neoplasms / Q000188:drug therapy / Q000276:immunology*; D003602:Cytotoxicity, Immunologic; D018450:Disease Progression; D005260:Female; D006801:Humans; D020014:K562 Cells; D007694:Killer Cells, Natural / Q000187:drug effects / Q000276:immunology* / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D014784:Mistletoe / Q000737:chemistry*; D008517:Phytotherapy; D010936:Plant Extracts / Q000494:pharmacology* / Q000627:therapeutic use; D011446:Prospective Studies; D016896:Treatment Outcome
chemical_list: D010936:Plant Extracts