Serum interleukin-18 and nitric oxide activity in bladder carcinoma

Background: Both interleukin-18 and nitric oxide are multifunctional molecules that are involved in the different steps of carcinogenesis. Methods: In the present study, we measured serum interleukin-18 and nitric oxide activity in 51 bladder cancer patients with different tumor stage and grade, and in 8 healthy controls. Serum nitrite-nitrate levels were measured as an index of nitric oxide generation. Results: Serum interleukin-18 levels were significantly higher in bladder cancer patients when compared to the control subjects (p > 0.05). Serum interleukin-18 levels were found to be higher in patients with Ta stage than patients with T1 and T2, T3, T4 stages and in patients with grade 1 tumors than patients with grade 2 and grade 3 tumors, but this was not statistically significant (p > 0.05). There was no significant difference in serum nitrite + nitrate levels between bladder cancer patients and control subjects. Conclusions: Elevated serum interleukin-18 levels in bladder carcinoma patients may be a result of host defence mechanism against the growth and progression of bladder cancer cells.