[Show abstract][Hide abstract] ABSTRACT: Androgen-binding protein (ABP) and oxytocin (OT) are among the factors that control smooth muscle proliferation and tumour growth through oxytocin receptor (OTR). A close functional interaction of OTR and caveolin 1 has been shown to modulate cell growth and proliferation. We investigated samples from 10 patients (mean age 68.3) who underwent transurethral prostate resection because of benign prostate hyperplasia (BPH) by immunohistochemistry. Post-mortem prostate samples of three young men (age 18, 28, 33) were used as controls. Tissue samples were embedded in epoxy resin and cut into serial 1 microm sections for colocalization of ABP, OTR, proliferation marker p21 and caveolin 1. ABP was found in stroma of the smooth muscle cells in all studied samples. OTR staining occurred in most of these cells in BPH while controls contained only scattered cells positive for OTR. There were no apparent differences in immunostaining for p21 while immunoreactivity for caveolin 1 was observed in most cells in BPH and only in few cells in controls. Caveolin 1 was mostly colocalized with ABP and OTR in BPH samples while controls did only occasionally show this colocalization. Our observations indicate an interaction of ABP and OTR, associated with caveolin 1, which may account in part for known non-genomic actions of gonadal steroids. Androgen dependent prostate growth in BPH may be linked to these mechanisms.
No preview · Article · Mar 2008 · Anantomia Histologia Embryologia
[Show abstract][Hide abstract] ABSTRACT: Several observations suggest that caveolin-1 has an important role in control of cell proliferation and cancerogenesis. For instance, oxytocin provokes a proliferative response in the prostate tissue when the oxytocin receptor is localized mainly in caveolin-1-enriched domains and an anti-proliferative effect when the same receptor is not localized in caveolae. Moreover, oxytocin concentrations are elevated in prostate tissue of patients with benign prostatic hyperplasia (BPH). In this study the expression pattern of the molecules caveolin-1, oxytocin receptor, androgen receptor and p21 (cell cycle arrest indicator) was investigated in the prostate tissue of BPH patients and of young controls. We found that both caveolin-1 and oxytocin receptor expression is drastically increased with age in both smooth muscle and epithelium of the prostate. We also found a significantly increased co-localization of the oxytocin receptor with caveolin-1 in both the muscle and the epithelium, especially in BPH patients. Androgen receptor and p21 staining was found throughout the prostate but did not change significantly with age or in BPH patients. We conclude that oxytocin may have a proliferative effect on the prostate tissue through the caveolae-associated receptors and thus contribute to BPH. This process seems to be androgen receptor independent.
No preview · Article · Nov 2007 · Anantomia Histologia Embryologia