Immunohistochemical detection of angiotensin receptors AT1 and AT2 in adrenal tumors.

Abstract

Angiotensin II is well known to affect the adrenal cell growth and function. Angiotensin receptors AT1 and AT2 were found to be present in the normal adrenal gland. However, the data on the expression of the angiotensin receptors in the adrenal tumors are very scarce. To overcome this gap, the paraffin sections of the adrenal cortical tumors and of pheochromocytomas from the archival material were immunostained with antibodies raised against AT1 (sc-1173) and AT2 (sc-9040) receptor proteins. In hyperplasia of the adrenal cortex and in benign adrenocortical adenomas, both functioning and non-functioning, the AT1 immunostaining was present mainly in the cell membranes. A positive immunoreaction was also found in the subpopulation of cell nuclei and within the cytoplasm. In the adrenal cancer, as well as in pheochromocytomas, neither cell membranes nor cell nuclei were immunostained with anti-AT1 antibody. However, a weak AT1 immunostaining was present within the cytoplasm of tumoral cells. With anti-AT2 antibody, in all tumors investigated, the tumoral cells were immunonegative but moderate to strong AT2 immunostaining was observed in the walls of intratumoral blood vessels and in the interstitial tissue. Our data indicates that the expression of AT1 receptors is altered in adrenal cancer and in pheochromocytomas. The expression of AT2 receptors, in turn, may be connected with the process of tumoral neo-angiogenesis.

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

“…AT1 expression is increased in highly differentiated, but not in poorly differentiated laryngeal cancers [19]. In adrenal tumors, AT1 expression is preserved or even increased in benign adenomas, but decreased in adrenal cancers [20]. The pattern of AT2 immunostaining in prostate cancer samples is identical as that of AT1, namely, the AT2 immunopositivity is enhanced at Gleason 2 grade but similar to the control at higher grades of malignancy.…”

Expression of angiotensin II receptors in aldosterone-producing adenoma of the adrenal gland and their clinical significance

“…International reports on AT 1 R expression in adrenocortical adenoma reveal different viewpoints. The expression of AT 1 R is normal according to Opocher [8] and Marek [9] , but Nawata [10] and Barbara [11] found AT 1 R expression was much higher in adenoma than in normal adrenal gland. In our study, we compared the expression of AT 1 R within adenoma and tissues adjacent to the tumor of 50 APA patients and 12 normal adrenal tissues.…”

Review of Markers of Zona Glomerulosa and Aldosterone-Producing Adenoma Cells

“…Receptors for Angiotensin II, a well-established stimulus of aldosterone secretion (Figure 1, panel E) and cell growth, 41,42 were reported two decades ago. 43,44 Only recently, however, a systematic investigation of human adrenal specimens has shown that type 1 receptors (AT1) are by far the most predominantly receptor in both normal adrenal cortex and APA; AT2 are 10-fold less expressed in the normal adrenal cortex, and even less in APAs.…”