SMARCC1 expression is upregulated in prostate cancer and positively correlated with tumour recurrence and dedifferentiation
S. Heebøll1,2,3, M. Borre2, P.D. Ottosen3, C.L. Andersen1, F. Mansilla1, L. Dyrskjøt1, T.F. Ørntoft1 and N. Tørring1
1Molecular Diagnostic Laboratory, Department of Clinical Biochemistry, Aarhus University Hospital - Skejby, 2Department of Urology, Aarhus University Hospital, Skejby and 3Department of Pathology, Aarhus University Hospital, Aarhus, Denmark.
Offprint requests to: Niels Tørring, Molecular Diagnostic Laboratory, Department of Clinical Biochemistry, Aarhus University Hospital - Skejby, Brenstrupgårdsvej 100, DK-8200 Aarhus N, Denmark. e-mail: nto@ki.au.dk
Summary. Background. The identification of new prognostic markers in prostate cancer (PC) is essential to improve patient treatment and management. Data suggest that SMARCC1 protein, a part of the intranuclear SWI/SNF complex which enhances the transactivation of the androgen receptor, is upregulated in PC and therefore a possible candidate marker for PC progression. Materials. Expression of SMARCC1 immunostaining was analysed on a tissue microarray containing specimens from 327 patients with prostate cancer and clinical follow-up information. Furthermore, 30 specimens from patients with benign prostate hyperplasia were included as controls as well as 30 specimens of benign prostate tissue from PC patients. Also, 18 specimens from lymph node metastases were analysed. Results. All benign specimens showed no or minimal staining for SMARCC1. In contrast, 20% of the specimens from patients with non-metastatic and non-recurrent disease showed moderate to marked staining. In 31% of the patients with recurrent disease and in 31% of the patients with metastatic disease we found moderate to strong SMARCC1 immunostaining. In total, 23% of lymph node metastases expressed SMARCC1. SMARCC1 expression was also positively correlated to Gleason score (p<0.05), clinical T stage (p<0.01) and time to recurrence (p<0.001). In a logistic regression analysis, patients with a marked SMARCC1 immunostaining had a significantly elevated odds ratio (OR) of 16 for recurrent cancer and an OR of 4.5 for metastatic disease. Conclusions. Our present results demonstrate an increased expression of SMARCC1 protein in prostate cancer and reveal a positive correlation with tumour dedifferentiation, progression, metastasis and time to recurrence. Histol Histopathol 23, 1069-1076 (2008)
Key words: Prostate cancer, SMARCC1, BAF155, Rissue microarray, Androgen receptor
DOI: 10.14670/HH-23.1069