HERV-K and HERV-H Env Proteins Induce a Humoral Response in Prostate Cancer Patients

A higher expression of human endogenous retroviruses (HERVs) has been associated with several malignancies, including prostate cancer, implying a possible use as a diagnostic or prognostic cancer biomarker. For this reason, we examined the humoral response against different epitopes obtained from the envelope protein of HERV-K (HERV-K env-su(19–37), HERV-K env-su(109–126)), HERV-H (HERV-H env-su(229–241), HERV-H env(387–399)) and HERV-W (HERV-W env-su(93–108), HERV-W env-su(248–262)) in the plasma of patients affected by prostate cancer (PCa), and compared to that of benign prostate hyperplasia (BPH) and a borderline group of patients with atypical small acinar proliferation (ASAP) and prostate intraepithelial neoplasia (PIN) and healthy controls. A significant antibody response was observed against HERV-K env-su(109–126) (p = 0.004) and HERV-H env-su(229–241) (p < 0.0001) in PCa patients compared to HCs, BPH and borderline cohorts, whilst no significance difference was found in the antibodies against HERV-W env-su(93–108) and HERV-W env-su(248–262) in patients with PCa. Our results provided further proof of the association between HERV-K and PCa and added new evidence about the possible involvement of HERV-H in PCa pathogenesis, highlighting their possibility of being used as biomarkers of the disease.