title: Clinical importance of serum interleukin-18 and nitric oxide activities in breast carcinoma patients.
abstract: BACKGROUND
  Interleukin-18 (IL-18) is a novel immunoregulatory cytokine that was known previously as interferon-gamma-inducing factor. IL-18 levels can be used as a serum indicator for monitoring the clinical course of patients with hematologic malignancies and gastric carcinoma. Nitric oxide (NO) is a pleiotropic molecule that participates in the multistep processing of carcinogenesis.
  
  
  METHODS
  In the current study, we measured serum IL-18 and nitrate and nitrite levels in 38 metastatic and 26 nonmetastatic breast carcinoma patients and 16 healthy control subjects. Serum nitrate and nitrite levels were measured as an index of NO generation.
  
  
  RESULTS
  The levels of serum IL-18 and nitrate and nitrite were increased significantly in breast carcinoma patients compared with control subjects (P < 0.001). Serum IL-18 levels were significantly higher in the metastatic patients compared with the nonmetastatic patients (P < 0.001). There was no difference in serum nitrate and nitrite levels between metastatic and nonmetastatic patients (P > 0.05). Patients with bone metastasis have higher serum IL-18 levels and lower serum nitrate and nitrite levels compared with patients with liver, lung, and local metastasis (P < 0.001). There was no correlation among serum IL-18, nitrate and nitrite, CA 15-3, and carcinoembryonic antigen levels (P > 0.05).
  
  
  CONCLUSIONS
  These findings suggest that serum IL-18 and nitrate and nitrite levels may be useful markers in monitoring metastatic breast carcinoma patients. IL-18 and NO activities in breast carcinoma patients with bone metastasis may be more valuable in the follow-up of these patients.
authors.affiliation: Department of Medical Oncology, Gazi University Medical School, Ankara, Turkey. nazangun@hotmail.com
authors.forename: Nazan
authors.initials: N
authors.lastname: Günel
authors.forename: Uğur
authors.initials: U
authors.lastname: Coşkun
authors.forename: Banu
authors.initials: B
authors.lastname: Sancak
authors.forename: Uğur
authors.initials: U
authors.lastname: Günel
authors.forename: Oğuz
authors.initials: O
authors.lastname: Hasdemir
authors.forename: Sükrü
authors.initials: S
authors.lastname: Bozkurt
mesh_terms: D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000097:blood / Q000473:pathology*; D002272:Carcinoembryonic Antigen / Q000097:blood; D005260:Female; D006801:Humans; D020382:Interleukin-18 / Q000097:blood*; D008875:Middle Aged; D018396:Mucin-1 / Q000097:blood; D009566:Nitrates / Q000097:blood; D009569:Nitric Oxide / Q000097:blood*; D009573:Nitrites / Q000097:blood
chemical_list: D002272:Carcinoembryonic Antigen; D020382:Interleukin-18; D018396:Mucin-1; D009566:Nitrates; D009573:Nitrites; D009569:Nitric Oxide