Original Article Prostatic acid phosphatase expression in human tissues
Thomas J. Graddis, Catherine J. McMahan, Jennifer Tamman, Keith J. Page, James B. Trager
Department of Immunology, University of Washington, Seattle, WA, USA; Cell Sciences and Immunology Department, Trubion Pharmaceuticals, Seattle, WA, USA; Deptartment of Molecular Biology, Dendreon Corporation, Seattle, WA, USA; Department of Molecular Pathology, Asterand UK Ltd, Herts UK; Department of Research, Dendreon Corporation, Seattle, WA, USA.
Received March 15, 2011; accepted March 21, 2011; Epub March 22, 2011; published March 31, 2011
Abstract: Prostate cancer is the most common cancer and the second leading cause of cancer deaths among males in most Western countries. Autologous cellular immunotherapy for the treatment of cancer seeks to induce tumor-specific immunity in the patient and is consequently dependent on a suitable target antigen and effective presentation of that antigen to the patient’s immune system. Prostatic acid phosphatase (PAP) has been tested as a target antigen due to its high and apparently specific expression in the prostate. We used a variety of approaches to analyze PAP expression, including immunohistochemistry, in situ hybridization, and quantitative polymerase chain reaction. We complemented these laboratory-based techniques with an in silico analysis of reported PAP expression in human cDNA libraries. Our studies confirmed that, while PAP expression is not restricted to prostate tissues, its expression in other human tissues is approximately 1-2 orders of magnitude less than that observed in the prostate. The relative specificity of PAP expression in the prostate supports its use as a target of autologous cellular immunotherapy. The approach described here, involving the use of multiple correlates of tissue-specific expression, is warranted as a prerequisite in selecting any suitable target for immunotherapy. (IJCEP1103006).
Address all correspondence to: James Trager, PhD Deptartment of Research Preclinical Development Dendreon Corporation 3005 First Avenue Seattle, WA 98121, USA. Tel: 206-829-1463; Fax: 206-829-1650 E-mail: jtrager@dendreon.com