Changes in immunophenotypes after neoadjuvant endocrine therapy for prostate cancer and their clinical significance.

Background: To investigate changes in the immunophenotypes of androgen receptor (AR), prostate-specific antigen (PSA), synaptophysin (Syn), chromogranin A (CgA), p53 and Ki-67 after neoadjuvant endocrine therapy (NET) for prostate cancer (PCa) and to analyze their clinical significance.

Methods: Paired paraffin samples were collected from 40 PCa patients before and after NET, and immunohistochemistry were used to detect AR, PSA, Syn, CgA, p53 and Ki-67 expression. Based on The Cancer Genome Atlas (TCGA), Kaplan‒Meier survival curves were plotted for analysis of PSA and Ki-67 expression in relation to progression-free survival (PFS).

Results: After NET, the mean scores for PSA and Ki-67 expression in PCa patients were lower than those before NET ( < 0.05), while the mean scores for Syn and CgA expression were higher than those before NET ( < 0.05). The mean Gleason score and WHO/ISUP (World Health Organization/International Society of Urological Pathology) grade after NET were lower than those before NET ( < 0.05). In PCa patients who had not yet received NET, PSA expression correlated positively with Gleason score and WHO/ISUP grade and negatively with Ki-67 expression ( < 0.05); p53 expression correlated negatively with Gleason score and WHO/ISUP grade ( < 0.05). TCGA showed that PFS was lower in PCa patients with high PSA and Ki-67 expression ( < 0.05).

Conclusions: PSA and Ki-67 protein expressions decreased significantly in PCa patients after NET and can be used as biological markers for prognostic assessment of PCa patients. NETs may induce a neuroendocrine (NE) phenotype in PCa. Monitoring the immunophenotypes of PCa patients after NET may inform assessment of efficacy and prognosis.