title: Distant metastases from prostatic carcinoma express androgen receptor protein.
abstract: Nearly all primary prostatic carcinomas have been found to express the androgen receptor (AR) protein, which is the intracellular mediator of androgen action. To gain a better insight into the mechanisms of androgen independence of advanced prostatic carcinoma, it is important to know whether the AR is also present in metastases of androgen-independent tumors. We have assessed the status of the AR and the prostate-specific antigen in 22 metastases of 18 patients with progressive prostate cancer. In 18 cases, the metastases were localized in bone, in 3 cases in the epidural space, and in 1 case in the periosteum. All but one patient had received some kind of endocrine treatment for prostatic carcinoma. Paraffin-embedded tissue sections were stained for the AR following a streptavidinbiotin-peroxidase protocol with the polyclonal antibody PG-21, which is directed against amino acids 1 through 21 of the rat and the human AR. The percentage of AR-positive cells was evaluated on the basis of an arbitrary 4-point scale. All 22 tumor metastases displayed AR positivity. One AR-positive metastatic lesion did not stain for prostate-specific antigen, but in all other metastases, this protein was detected by means of immunohistochemistry. The present study provides evidence that, unlike androgen-independent prostatic carcinoma cell lines, distant prostatic carcinoma metastases do express the AR. These findings indicate that the AR may be involved in the progression of prostate cancer.
authors.affiliation: Department of Urology, University of Innsbruck, Austria.
authors.forename: A
authors.initials: A
authors.lastname: Hobisch
authors.forename: Z
authors.initials: Z
authors.lastname: Culig
authors.forename: C
authors.initials: C
authors.lastname: Radmayr
authors.forename: G
authors.initials: G
authors.lastname: Bartsch
authors.forename: H
authors.initials: H
authors.lastname: Klocker
authors.forename: A
authors.initials: A
authors.lastname: Hittmair
mesh_terms: D001859:Bone Neoplasms / Q000737:chemistry / Q000556:secondary* / Q000648:ultrastructure*; D004824:Epidural Space / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D009362:Neoplasm Metastasis / Q000175:diagnosis; D010521:Periosteum / Q000473:pathology; D017430:Prostate-Specific Antigen / Q000032:analysis; D011471:Prostatic Neoplasms / Q000737:chemistry / Q000473:pathology* / Q000648:ultrastructure*; D011944:Receptors, Androgen / Q000032:analysis*
chemical_list: D011944:Receptors, Androgen; D017430:Prostate-Specific Antigen