Objective: Our purpose was to determine the clinical significance of interleukin-1 receptor antagonist (IL-1ra), which is an endogenous inhibitor cytokine of IL-1, in patients with cervical carcinoma.
Methods: Tissue IL-1ra expression and serum IL-1ra level were examined by enzyme-linked immunosorbent assay (ELISA), Western blotting, and immunohistochemistry in normal controls and patients with cervical carcinoma.
Results: Tissue IL-1ra protein level by ELISA was significantly higher in squamous cell carcinoma (n = 9) than in the normal cervix (n = 7) and adenocarcinoma (n = 3). Western blotting confirmed the main presence of intracellular IL-1ra type 1 in squamous cell carcinoma. Immunohistochemistry demonstrated significant IL-1ra expression only in tumor cells of squamous cell carcinoma. Elevation of serum IL-1ra level was found in patients with squamous cell carcinoma (n = 38) compared to normal women (n = 13), but not in patients with adenocarcinoma (n = 9). Although serum IL-1ra level did not correlate with clinical stage or any other tumor marker, high serum IL-1ra level was associated with pelvic lymph node metastasis and poor prognosis in patients with squamous cell carcinoma. On the other hand, these results were not obtained in patients with cervical adenocarcinoma.
Conclusion: IL-1ra may play important roles in local and general malignant behaviors in patients with cervical squamous cell carcinoma, and measurement of serum IL-1ra level may be useful in predicting patient survival.