OBJECTIVE: To determine the expression of the cytokines transforming growth factor-β1 (TGF-β1), interferon-γ (IFN-γ), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) in serum from patients with Peyronie's disease (PD) compared to healthy controls. MATERIALS AND METHODS: Ninety-one consecutive PD patients aged 20 - 74 years were included in this study. All patients were diagnosed with symptomatic PD for the first time and had a palpable penile plaque. The patients previously had the disease for 6 - 72 months. None of the patients had a severe infectious disease or known systemic illness. For cytokine analyses, peripheral venous blood samples were obtained before treatment. Fifty healthy male blood donors aged 22 - 64 years served as the control group. TGF-β1, IFN-γ, Il-6, and TNF-α were analyzed quantitatively with commercial immunoassays. RESULTS: Mean cytokine levels in serum from patients were increased for TGF-β1 and IFN-γ compared to healthy controls. The difference for TGF-β1 was considered statistically significant (p < 0.001). IL-6 was not detectable in PD patients (p < 0.01) and TNF-α was decreased (p < 0.0001). CONCLUSION: The significantly elevated serum level of the profibrotic TGF-β1 cytokine underscores the effect of cytokines in the pathophysiology of PD. The significantly decreased TNF-α serum level suggested no acute immunomodulatory process. Therefore, the relevance for therapeutic administration of TNF-α should be further investigated. Quantification of TGF-β1 in serum of PD patients provides a possible diagnostic tool and target for therapy. The data on altered cytokine levels in PD patients also provide a new understanding for etiopathogenesis of PD, which warrants further investigation.
Peyronie's disease; pathophysiology; cytokines; IL-6; TNF-α; TGF-β; IFN-γ
