The Expression And Its Clinical Significance Of PALB2 In Castration-resistant Prostate Cancer

ObjectiveTo study the relationship of the expression level of partner and localizer of breast cancer susceptibility gene 2(BRCA2)(PALB2)in the castration-resistant prostate cancer(CRPC)tissues with its clinical and pathological features.MethodsForty-six CRPC specimens and its clinical and pathological factors including 36 samples from patients with prostate adenocarcinoma,10 samples from patients with neuroendocrine prostate cancer(NEPC)and 20 benign prostatic hyperplasia(BPH)specimens(as the control)were collected from January 2015 to June 2017 in the Second Hospital of Tianjin Medical University.The expression of PALB2 protein was detected by immunohistochemistry.The relationships of PALB2 expression with the clinical and pathological features of CRPC patients were analyzed.ResultsThe positive expression rate of PALB2 protein in CRPC tissues was 80.4%(37/46),which was significantly lower than that in BPH tissues [95.0%(19/20),P = 0.024].The positive expression rate of PALB2 protein was not significantly different in terms of age,primary tumor status,lymph node metastasis and prostate-specific antigen(PSA)level(all P > 0.05),but it was significantly different in terms of Gleason score and pathological type of CRPC(both P < 0.05).The expression level of PALB2 in patients with Gleason score >8 was lower than that in patients with Gleason score?8(P = 0.026).Its expression level was also significantly lower in the NEPC than in the prostate adenocarcinoma tissue(P = 0.005).Further correlation analysis showed that PALB2 expression rate was negatively correlated to Gleason score(r =-0.376,P = 0.024)and pathological type(r =-0.418,P = 0.004).ConclusionThe positive rate of PALB2 expression is decreased in CRPC tissues,which can reflect the proliferation and differentiation of CRPC cells and may be correlated to the occurrence and progress of tumors.