RT Journal Article SR Electronic T1 Ovarian Renin—Angiotensin System-regulating Aminopeptidases Are Involved in Progesterone Overproduction in Rats with Mammary Tumours Induced by N-Methyl Nitrosourea JF Anticancer Research JO Anticancer Res FD International Institute of Anticancer Research SP 4633 OP 4637 VO 29 IS 11 A1 MARÍA DEL PILAR CARRERA A1 MARÍA JESÚS RAMÍREZ-EXPÓSITO A1 MARÍA JESÚS GARCÍA A1 MARÍA DOLORES MAYAS A1 JOSÉ MANUEL MARTÍNEZ-MARTOS YR 2009 UL http://ar.iiarjournals.org/content/29/11/4633.abstract AB A local renin-angiotensin system (RAS) has been found in ovary. This ovarian RAS may regulate ovarian steroidogenesis. Ample studies show that the ovarian hormones estradiol (E2) and progesterone (P) are strongly implicated in the development of breast cancer. Materials and Methods: The aim of the present work was to elucidate if alterations in ovarian RAS, analyzed through their proteolytic regulatory enzymes aminopeptidase A (APA), B (APB) and N (APN), could be responsible for an altered steroidogenesis in rats with mammary tumours induced by N-methyl nitrosourea (NMU). Results: We describe here a highly significant increase of serum P levels in NMU-treated rats, concomitantly with an increase in ovarian aspartyl and glutamyl aminopeptidase activities (named together as APA activity). Moreover, we did not find changes in APB or APN activities, suggesting an increased metabolism from Ang II to Ang III and a decreased catabolism of Ang III. Conclusion: The relationship between ovarian RAS and P overproduction in a rat model of mammary carcinogenesis indicates ovarian RAS as a new potential target in breast cancer therapy.