Research articleCytokine profiling identifies an interaction of IL-6 and IL-1α to drive PSMA-PSA prostate clones

BackgroundSeveral PSMA-PSA prostate clones have been identified during prostate cancer progression; however, until now, their in situ inflammatory characteristics have remained unclear.AimWe therefore investigated the interplay between proinflammatory cytokines and (PSMA,PSA) sub-groups.Materials and methods27 benign prostate hyperplasia (BPH) and 18 prostate cancers (PC) were enrolled in this study. Immunohistochemical analysis was performed. Serum levels of PSA were assayed by Immulite autoanalyser.ResultsIn BPH and PC patients with elevated serum PSA levels, IL-1α was the most proinflammatory cytokine expressed in (PSMA+,PSA−) subgroup. However, most samples of (PSMA+,PSA+) subgroup had positive immunoreaction to IL-6. In samples of PC with PSA serum levels of 4-20 ng/mL or >20 ng/mL, immunoreaction to TNF-α was seen only in (PSMA+,PSA+) subgroup. Interestingly, several combinations of proinflammatory cytokines (IL-6, IL-1α and TNF-α) showed that coexpression of tissue PSMA and PSA was concomitant with high immunoreactions to (IL-6+,TNF-α-), (IL-6+,IL-1α+) and (IL-1α+,TNFα−) in BPH and PC patients. (PSMA,PSA) subgroup lacking tissue PSA expression showed a high immunoexpression of the profile (IL-6+,TNF-α-). The combinations of (IL-6-, TNF-α-) and (IL-6-, IL-1α-) were absent in (PSMA+,PSA−) and (PSMA+,PSA+) BPH sub-groups.ConclusionCollectively, these findings underscore the importance of TNF-α and highlight the interaction between IL-6 and IL-1α to generate an inflammatory microenvironment in driving (PSMA,PSA) prostate clones.