title: Serum levels of interleukin-18 (IL-18) and soluble interleukin-2 receptor (sIL-2R) in lung cancer.
abstract: OBJECTIVE
  We evaluated the clinical usefulness of interleukin-18 (IL-18) and soluble interleukin-2 receptor (sIL-2R) during chemotherapy of lung cancer in relation to the histological type of the tumor, clinical stage, response to therapy and time survival.
  
  
  METHODS
  Serum levels of IL-18 and sIL-2R were determined in 73 patients (62 males; mean age 64 years; 41 with non-small cell lung cancer-NSCLC, 32 with small cell lung cancer-SCLC); 12 healthy subjects served as controls. To determine IL-18 serum concentrations (Elisa), venous blood samples were collected from each patient before and after chemotherapy.
  
  
  RESULTS
  The mean serum IL-18 level in all patients with lung cancer was significantly higher compared with healthy volunteers (p = 0.0001; NSCLC vs control p = 0.0001; SCLC vs control p = 0.004). In NSCLC group with stage IV the mean IL-18 level was significantly higher than those with stage IIIB (p = 0.04). Regarding tumor stage and response to therapy, no significant differences in IL-18 were observed. Using cut-off serum IL-18 concentration of 319.6 pg/ml, the prognoses of the two groups were different, but it was not statistically significant. The serum levels of sIL-2R in NSCLC patients were significantly higher than in controls (p = 0.018). There were no significant differences in serum sIL-2R levels in relation to clinical stage of lung cancer and response to therapy. The cut-off value between high and low serum sIL-2R concentration was defined as 582.27 U/ml. The difference in survival rate between the high and low sIL-2R groups was not significant.
  
  
  CONCLUSIONS
  Serum IL-18 and sIL-2R levels can be useful in clinical practice, but their practical significance needs further studies.
authors.affiliation: Department of Pneumonology and Tuberculosis, Medical University of Bialystok, Poland. naumw@mp.pl
authors.forename: W
authors.initials: W
authors.lastname: Naumnik
authors.forename: E
authors.initials: E
authors.lastname: Chyczewska
authors.forename: O
authors.initials: O
authors.lastname: Kovalchuk
authors.forename: J
authors.initials: J
authors.lastname: Tałałaj
authors.forename: T
authors.initials: T
authors.lastname: Izycki
authors.forename: B
authors.initials: B
authors.lastname: Panek
mesh_terms: D000970:Antineoplastic Agents / Q000627:therapeutic use; D014408:Biomarkers, Tumor / Q000097:blood*; D002289:Carcinoma, Non-Small-Cell Lung / Q000097:blood* / Q000188:drug therapy; D018288:Carcinoma, Small Cell / Q000097:blood* / Q000188:drug therapy; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D020382:Interleukin-18 / Q000097:blood*; D008175:Lung Neoplasms / Q000097:blood* / Q000188:drug therapy / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D015375:Receptors, Interleukin-2 / Q000097:blood*
chemical_list: D000970:Antineoplastic Agents; D014408:Biomarkers, Tumor; D020382:Interleukin-18; D015375:Receptors, Interleukin-2