Abstract
Individualized treatment of prostate cancer depends on an accurate stratification of patients who are sensitive to various treatments. Interleukin-23 (IL-23) was reported to play a significant role in prostate cancer. Here, we aimed to explore the clinical value of IL-23-secreting (IL-23+) cells in prostate cancer patients. We evaluated interleukin-23A (IL-23A) expression in The Cancer Genome Atlas database and retrospectively enrolled 179 treatment-naïve metastatic prostate cancer patients diagnosed in our institute between June 2012 and December 2014. IL-23+ cells were stained and evaluated via immunohistochemistry. Further, survival and multivariate Cox regression analyses were conducted to explore the prognostic value of IL-23+ cells. We found that IL-23A expression correlated with disease progression, while IL-23+ cells were clearly stained within prostate cancer tissue. Patients with higher Gleason scores and multiple metastatic lesions tended to have more IL-23+ cell infiltration. Further analyses showed that patients with higher levels of IL-23+ cells had significantly worse overall survival (hazard ratio [HR] = 2.996, 95% confidence interval [95% CI]: 1.812-4.955; P = 0.001) and a higher risk of developing castration resistance (HR = 2.725, 95% CI: 1.865-3.981; P = 0.001). Moreover, subgroup analyses showed that when patients progressed to a castration-resistant status, the prognostic value of IL-23+ cells was observed only in patients treated with abiraterone instead of docetaxel. Therefore, we showed that high IL-23+ cell infiltration is an independent prognosticator in patients with metastatic prostate cancer. IL-23+ cell infiltration may correlate with abiraterone effectiveness in castration-resistant prostate cancer patients.