Signaling between Prostatic Stem Cells (PSCs) and Steroid Hormone Receptors (SHRs) in Elderly Men with Nodular Hyperplasia (NH), High-Grade Prostatic Intraepithelial Neoplasia (HGPIN), Cancer (CA) or No Lesions
VHA Cagnon, AC Hetzl, F Montico, U Ferreira, A Billis, WJ Favaro. School of Medicine, University of Campinas (Unicamp), Campinas, Brazil
Background: PSCs are involved in the complex mechanisms of signaling. The aim of this study is to characterize PSCs in both the prostatic stroma and glandular epithelium and to establish the signaling between these cells and the SHRs in the prostate of elderly men with NH, HGPIN, CA or no lesions.
Design: Sixty sections of the peripheral zone from men 60 to 90-year-old were divided into 4 groups: no lesions (Group 1); with NH (Group 2); with HGPIN (Group 3); and, with CA (Group 4). The sections were submitted to immunohistochemistry and Western Blotting analysis for androgen receptor (AR), α- and β-estrogen receptor (αER, βER), CD44, CD133, CD117, p63, ABCG2 and vimentin.
Results: Both prostatic stroma and glandular epithelium had PSCs cells which were more frequently seen in the basal compartment of the epithelium of Group1. The PSCs of the luminal compartment of the epithelium were CD44/CD133/CD117/βER+ and the PSCs of the basal compartment were CD44/CD133/p63/βER+. These PSCs had intense immunoreactivity in Group 1 comparing to Groups 2 and 3. The stromal PSCs were CD133/Vimentin/AR+ in all groups. PSCs in Group 4 were ABCG2/CD44/CD133/p63/αER+ in the luminal compartment and ABCG2/Vimentin/αER+ in the stromal compartment. Intensified AR immunoreactivity was verified in the secretory compartment from all groups. However, this receptor was only intense in the stromal compartment in Groups 2, 3 and 4. αER immunoreactivity was intense in the luminal and stromal compartments from Groups 2, 3, and 4. βER was present mainly in the epithelial compartment and only in the stromal compartment of Groups 2 and 3.
Conclusions: NH, HGPIN, and CA were characterized by distinct AR and αER reactivities in the stromal compartment indicating an important signaling for PSCs. βER was fundamental to signal the epithelial PSCs, although there was no positive PSCs in the Group of CA. The dynamic paracrine signaling of the SHRs discloses the role of these hormones in the activation mechanisms of PSCs in normal prostates as well as with disease. The understanding of the signaling between PSCs and SHRs may be crucial for the development of therapy in malignant prostatic diseases.
Category: Genitourinary (including renal tumors)
Wednesday, March 24, 2010 1:00 PM
Poster Session VI # 113, Wednesday Afternoon