Background: To investigate the prognostic value of expression levels of nin one binding protein (Nob1) in prostate carcinoma.
Methods: Nob1 protein levels were evaluated by Western blot in samples from 40 prostate carcinomas and matched adjacent non-neoplastic prostate tissues. Nob1 expression was also assessed by immunohistochemistry in samples from 300 prostate carcinoma and matched adjacent non-neoplastic prostate tissues, as well as 20 benign prostatic hyperplasia samples. The findings were compared with clinical and pathologic parameters and patient outcome.
Results: Nob1 protein analysis showed significant differences between the prostate carcinomas and control groups tested. Immunohistochemical analysis showed that Nob1 positivity was higher in prostate carcinoma than that in paired adjacent non-cancerous tissues (58 vs 7 %, P < 0.001). Nob1 positivity was significantly associated with high Gleason scores and metastasis in patients. Nob1 expression was significantly associated with shorter biochemical recurrence-free survival (BCRFS). Multivariate analysis revealed that Nob1 is an independent marker for BCRFS.
Conclusions: These findings provide evidence that Nob1 is an indicator of poor prognosis in prostate carcinoma.