The use of molecular targets in novel strategies of tumor treatment largely depends on the identification of proteins with a tumor- or tissue-restricted expression. We identified the novel protein D-GPCR that is selectively overexpressed in human prostate cancer and prostate and belongs to the subfamily of odorant-like orphan G protein-coupled receptors. Quantification of D-GPCR transcripts in different human tissues by real-time PCR demonstrated 27-fold overexpression in prostate compared to skeletal muscle, the organ with second highest transcript numbers in males. Investigation of tumor/normal cDNA pairs obtained from 241 cancer patients including four prostate tumors confirmed the preferential expression in prostate. When comparing the mean transcript level of 15 prostate cancer tissues to their non-tumorous counterparts, D-GPCR was almost 6-fold upregulated. Coupled in vitro transcription and translation of D-GPCR cDNA produced a protein band of approximately 28 k Da. Recombinant, His-tagged protein was expressed in transfected HEK293 cells and gave rise to a 30 kDa band specifically detected by anti-His antibody. These data provide the basis for future studies evaluating the diagnostic potential of D-GPCR and its utility as a novel target in immunotherapy of prostate cancer. (C) 2004 Elsevier Inc. All rights reserved.