Role of interleukin-8 in onset of the immune response in intravesical BCG therapy for superficial bladder cancer.

In intravesical therapy for superficial bladder carcinoma urothelial cells may, through the production of cytokines, contribute to the bacillus Calmette-Guerin (BCG)-induced local immunological reaction and associated antitumor efficacy. The aim of this study was to investigate such a role for the neutrophil-attracting cytokine interleukin-8 (IL-8). The appearance of IL-8 in patients urine after BCG therapy was compared with BCG-induced IL-6 and IL-2 and the stability of IL-8 in urine was tested. Compared to IL-6 and IL-2, a rapid induction of IL-8 was observed, occurring after the first BCG instillation. Urinary IL-8 was highly stable, even after 24 h incubation at 37 degrees C. The IL-8 concentration after the first instillation seemed to be associated with subsequent development of an immune response. Consequently, IL-8 seems an attractive candidate for investigation of its prognostic value for a clinical response to BCG therapy.