title: Analysis of interleukin-2/interleukin-2 receptor system in advanced non-small-cell lung cancer.
abstract: OBJECTIVE
  The purpose of the study was to investigate the IL-2/IL-2 receptor system in patients with advanced non-small-cell lung cancer (NSCLC).
  
  
  METHODS
  Sera from 40 subjects and 80 patients with stage III and IV NSCLC were assayed for soluble interleukin-2 receptor (sIL-2R) and interleukin-2 (IL-2) by the enzyme-linked immunosorbent assay. Circulating CD25+ cells were analyzed by flow cytoflorimetry. The data were related to clinical status by comparing the levels of sIL-2R and IL-2 at diagnosis and during the treatment.
  
  
  RESULTS
  The mean sIL-2R concentrations of the NSCLC patients were significantly higher than the control population (P=0.0001); the patients with metastatic disease had significantly higher levels than those with locally advanced disease (P=0.02). No correlation was seen between circulating CD25+ cells and sIL-2R levels. Disease progression was associated with an increase in sIL-2R levels and a decline in IL-2; the sIL-2R/IL-2 ratio showed a gradual increase with tumor progression.
  
  
  CONCLUSIONS
  Our study demonstrates in a large series of patients that in advanced NSCLC there is an imbalance of the IL-2/IL-2 receptor system. Furthermore, circulating sIL-2R levels and the sIL-2R/IL-2 ratio may be useful as markers of disease activity and treatment response, suggesting a potential prognostic value.
authors.affiliation: Department of Internal and Experimental Medicine F. Magrassi, II University of Naples, Italy.
authors.forename: F
authors.initials: F
authors.lastname: De Vita
authors.forename: G
authors.initials: G
authors.lastname: Turitto
authors.forename: M
authors.initials: M
authors.lastname: di Grazia
authors.forename: A
authors.initials: A
authors.lastname: Frattolillo
authors.forename: G
authors.initials: G
authors.lastname: Catalano
mesh_terms: D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000097:blood*; D002289:Carcinoma, Non-Small-Cell Lung / Q000097:blood* / Q000473:pathology / Q000628:therapy; D016022:Case-Control Studies; D018450:Disease Progression; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D007376:Interleukin-2 / Q000097:blood*; D008175:Lung Neoplasms / Q000097:blood* / Q000473:pathology / Q000628:therapy; D008297:Male; D008875:Middle Aged; D015375:Receptors, Interleukin-2 / Q000097:blood*
chemical_list: D014408:Biomarkers, Tumor; D007376:Interleukin-2; D015375:Receptors, Interleukin-2