Analysis Of Serum IL-35 In Patients Undergoing Prostate Biopsy

Purpose:IL-35 is a novel inhibitory cytokine and has recently been implicated in tumor immunity. However, the role of IL-35 in patients with prostate cancer(PCa)have never been investigated. To investigate the expression situation of serum IL-35 in patients undergoing prostate biopsy and discuss its clinical significance.Methods:A total of 180 patients undergoing prostate biopsy were enrolled in this study, serum samples collected from patients were tested by IL-35 enzyme linked immunosorbent assay(ELISA) and relationships between serum IL-35 levels and clinical characteristics were evaluated. The predictive value of IL-35 was evaluated using multivariate logistic regression and receiver operating characteristic(ROC)curve analyses.Results : PCa was identified in 75(41.6%) patients. Serum IL-35 levels were significantly higher in PCa patients(134.48±78.48 pg/mL) than those of non-PCa patients(67.22±24.08 pg/mL). On multivariate logistic regression, IL-35 was significantly associated with PCa(p<0.001). ROC analysis showed us that IL-35 played a great role in prediction of PCa in all patients. Area under ROC curve(AUC)= 0.82, with the cutoff value of 81.3 pg/ml, at that point, IL-35 discriminated PCa from non-PCa patients with 74.7% sensitivity, 81.0% specificity and 78.3% diagnostic accuracy. Furthermore, The AUC for IL-35 in the discrimination of PCa from non-PCa patients in a subset with PSA of 4 to 10 ng/ml was 0.757. Further analysis suggested that IL-35 level obviously higher in advanced PCa patients than localized PCa patients. IL-35 was also significantly higher in bone metastasis positive patients.Conclusion: Circulating IL-35 in PCa patients were significantly increased,suggesting that IL-35 is a potential biomarker and may be a practicable parameter in identifying patients at risk for PCa and predicting the stage of PCa before initial prostate biopsy.Through the determination of IL-35 we also expect to reduce the unnecessary prostate biopsy.