BASIC SCIENCE Immunohistochemical detection of angiotensin AT1 and AT2 receptors in prostate cancer

Abstract

IntroductionThe human prostate gland contains all the compounds of the renin-angiotensin system (RAS), including AT1 and AT2 angiotensin receptors. The role of local RAS in the prostate pathology is recently discussed. The aim of the present study was the evaluation of AT1 and AT2 expressions in human prostate cancers.Material and methodsThe investigation was performed in 20 paraffin-embedded needle biopsy specimens from routine diagnostic prostate cancer biopsies. The specimens were stained with hematoxylin and eosin and immunostained with anti-AT1 and anti-AT2 antibodies. For visualization of primary antibodies, the streptavidin-biotin-peroxidase technique was applied. The expression of both receptor proteins was evaluated quantitatively using image analysis method.ResultsThe positive immunostaining with both anti- AT1 and anti-AT2 antibodies can be found in stromal as well as epithelial structures. The results of quantitative evaluation showed the positive correlation between AT1 and AT2 expressions in neoplastic epithelium and overexpression of both AT1 and AT2 in neoplastic epithelium of Gleason grade 2, but not in cancerous structures of Gleason grades 3-5.ConclusionsThe data on AT1 and AT2 receptor expressions may suggest the involvement of RAS in prostate cancerogenesis. Moreover, the persistence of AT1 receptors in prostate cancer speaks in favor of attempts to use of AT1 receptor blockers (i.e. sartanes) and/or AT2 agonists in prostate cancer prophylaxis and/or treatment.

Interaction between angiotensin II and relaxin 2 in the progress of growth and spread of prostate cancer cells

“…Uemura et al (29) found that AT1 receptor mRNA was strongly expressed in LNCaP cells and very poorly in PC3, which may explain the better response of the first line to angiotensin II-induced cell proliferation. Our observation seems compatible also with finding of Pawlikowski et al (30) presenting that expression of Ang II type 1 and 2 receptors in neoplastic epithelium of Gleason grate 2 is higher than in more advanced cancerous structures of Gleason grades 3-5. On the contrary, Chow et al (31) demonstrated that Ang II dose-dependently stimulated DNA synthesis in LNCaP but not PC3 cells suggesting that only LNCaP has the functional state of AT1.…”

Effects of testosterone and 17β-estradiol on angiotensin-induced changes in tyrosine kinase activity in the androgen-independent human prostate cancer cell line, DU145

“…As mentioned earlier, expression of AT1R and AT2R was found in prostate cancer cells (46,47) while expression of both types of receptors can differ in LNcaP and dU145 cells (47). In androgen-positive LNcap cells AT1R expression is higher than in late stage, androgen-independent dU154 cells and in healthy cells (34).…”