Decreased retinoid X receptor-α protein expression in basal cells occurs in the early stage of human prostate cancer development Journal Article
| Authors: | Mao, G. E.; Reuter, V. E.; Cordon-Cardo, C.; Dalbagni, G.; Scher, H. I.; Dekernion, J. B.; Zhang, Z. F.; Rao, J. |
| Article Title: | Decreased retinoid X receptor-α protein expression in basal cells occurs in the early stage of human prostate cancer development |
| Abstract: | The development of prostatic intraepithelial neoplasia (PIN)-like lesions in the prostate-specific retinoid X receptor-α (RXRα) null mouse suggests that RXRα may protect against neoplasia. The purpose of this study was to characterize RXRα protein expression in human prostate to determine if RXRα is altered in early stages of tumor progression. Immunohistochemistry with anti-RXRα antibody was performed on 138 fresh frozen prostate specimens collected from 27 noncarcinomatous prostates and 111 radical prostatectomy samples of prostate adenocarcinoma (CA). The RXRα signal intensity was scored using a scale of 0-3. In normal glands, RXRα was expressed strongly in basal cells and only weakly in secretory epithelial cells. This finding was confirmed by double immunofluorescence labeling of RXRα and Keratin-903, a basal cell marker, followed by confocal microscopic examination. In basal cells, a gradual decrease of RXRα expression was noted from normal glands of noncarcinomatous prostate (3.0 ± 0) to "normal" glands distant to CA (2.13 ± 0.44) to "normal" glands adjacent to CA (1.25 ± 0.53) and high-grade PIN (0.56 ± 0.58). While nearly all "normal" glands from 138 specimens were positive for RXRα in basal cells, only 48% (13 of 27) of the high-grade PIN glands appeared positive. Moreover, basal cell expression of RXRα in "normal" tissue was less in specimens with poorly differentiated tumor (Gleason score ≥ 8; 1.83 ± 0.36) compared with well-differentiated tumor (Gleason score < 6; 2.35 ± 0.34; P = 0.04). Thus, a decrease of RXRα in the basal cells may serve as a marker for prostate CA-associated field change, which may represent an early event in the prostate carcinogenic process. These findings suggest that chemoprevention strategies with retinoids may be most effective if applied during the early stages of transformation. |
| Keywords: | immunohistochemistry; adult; controlled study; human tissue; protein expression; aged; middle aged; major clinical study; genetics; disease course; histopathology; pathophysiology; cancer staging; neoplasm staging; cancer grading; protein function; adenocarcinoma; chemoprophylaxis; confocal microscopy; tumor differentiation; cell differentiation; immunofluorescence; tumor marker; carcinogenesis; cell transformation, neoplastic; monoclonal antibody; prostate cancer; prostatic neoplasms; gene expression regulation; gene expression regulation, neoplastic; biosynthesis; basal cell; cell transformation; prostatectomy; disease progression; transactivator protein; prostate tumor; carcinoma in situ; scoring system; epithelium cell; prostate adenocarcinoma; prostatic intraepithelial neoplasia; trans-activators; tumor growth; malignant transformation; frozen section; retinoid x receptor alpha; receptors, cytoplasmic and nuclear; retinoic acid receptor; keratin; chemoprevention; cell receptor; receptors, retinoic acid; humans; human; male; priority journal; article; rar related orphan receptor a; rar-related orphan receptor a |
| Journal Title: | Cancer Epidemiology Biomarkers and Prevention |
| Volume: | 13 |
| Issue: | 3 |
| ISSN: | 1055-9965 |
| Publisher: | American Association for Cancer Research |
| Date Published: | 2004-03-01 |
| Start Page: | 383 |
| End Page: | 390 |
| Language: | English |
| PROVIDER: | scopus |
| PUBMED: | 15006913 |
| DOI/URL: | |
| Notes: | Cancer Epidemiol. Biomarkers Prev. -- Cited By (since 1996):12 -- Export Date: 16 June 2014 -- CODEN: CEBPE C2 - 15006913 -- Source: Scopus |
