1. ¹Department of Surgical Pathology, University Hospital Zurich, Zurich, Switzerland
2. ²Institute of Pathology, Charité - Universitätsmedizin Berlin, Berlin, Germany
3. ³Department of Urology, Charité - Universitätsmedizin Berlin, Berlin, Germany
4. ⁴Department of Surgery, University Hospital Dresden, Dresden, Germany

Correspondence: Dr G Kristiansen, Department of Pathology, Institute of Surgical Pathology, University Hospital Zurich (USZ), Schmelzbergstr. 12, Zurich 8091, Switzerland. E-mail: glen.kristiansen@usz.ch

Received 8 May 2008; Revised 24 July 2008; Accepted 24 July 2008.

Abstract

GOLPH2 is coding the 73-kDa type II Golgi membrane antigen GOLPH2/GP73. Upregulation of GOLPH2 mRNA has been recently reported in expression array analyses of prostate cancer. As GOLPH2 protein expression in prostate tissues is currently unknown, this study aimed at a comprehensive analysis of GOLPH2 protein in benign and malignant prostate lesions. Immunohistochemically detected GOLPH2 protein expression was compared with the basal cell marker p63 and the prostate cancer marker -methylacyl-CoA racemase (AMACR) in 614 radical prostatectomy specimens. GOLPH2 exhibited a perinuclear Golgi-type staining pattern and was preferentially seen in prostatic gland epithelia. Using a semiquantitative staining intensity score, GOLPH2 expression was significantly higher in prostate cancer glands compared with normal glands (P<0.001). GOLPH2 protein was upregulated in 567 of 614 tumours (92.3%) and AMACR in 583 of 614 tumours (95%) (correlation coefficient 0.113, P=0.005). Importantly, GOLPH2 immunohistochemistry exhibited a lower level of intratumoral heterogeneity (25 vs 45%). Further, GOLPH2 upregulation was detected in 26 of 31 (84%) AMACR-negative prostate cancer cases. These data clearly suggest GOLPH2 as an additional ancillary positive marker for tissue-based diagnosis of prostate cancer.