title: Targeting aminopeptidase N (APN/CD13) with cyclic-imide peptidomimetics derivative CIP-13F inhibits the growth of human ovarian carcinoma cells.
abstract: Aminopeptidase N (APN/CD13) is an essential peptidase involved in the process of tumor growth, metastasis and angiogenesis. Inhibition of APN/CD13 may be an effective strategy for cancer treatment. CIP-13F is a cyclic-imide peptidomimetics compound designed to fit the active pockets S1 and S'1 of APN/CD13 that act in tumor proliferation. Our aim in this study was to evaluate the efficacy of CIP-13F as a candidate compound for cancer treatment. The experiments were performed on the human ovarian carcinoma (OVCA) ES-2 and HRA cell lines, which have high and low levels of APN/CD13 respectively. CIP-13F significantly blocked APN/CD13 activity on the surface of ES-2 cells as measured by quantitating the enzymatic cleavage of the substrate l-leucine-p-nitroanilide. CIP-13F effectively inhibited ES-2 cell growth and migration without significant cytotoxic effect. In contrast, CIP-13F did not significantly inhibit HRA cell growth, indicating that CIP-13F may inhibit ES-2 cell growth via suppression of APN/CD13. The suppression of APN/CD13 was also observed by using the assays of flow cytometry and Western blot analysis. Further, the inhibitory effects of CIP-13F on APN/CD13 and on ES-2 proliferation were supported by the induction of ES-2 apoptosis. CIP-13F-treated ES-2 cells resulted apoptotic characteristics, such as induction of externalization of phosphatidylserine and DNA laddering fragment. The activation of caspase-3 and poly ADP-ribose polymerase (PARP) was also enhanced. The inhibitory effects of CIP-13F on APN/CD13 expression and on ES-2 proliferation were confirmed in mice bearing ES-2 xenografts. CIP-13F delayed the growth of ES-2 xenografts in mice after 2 weeks of vena caudalis injection. These results suggest that CIP-13F has a high inhibitory effect on the growth of OVCA cells via decreasing the activity and expression of APN/CD13.
authors.affiliation: Shandong Medical Biotechnology Centre, Jinan 250062, China.
authors.forename: Shu-Xiang
authors.initials: SX
authors.lastname: Cui
authors.forename: Xian-Jun
authors.initials: XJ
authors.lastname: Qu
authors.forename: Zu-Hua
authors.initials: ZH
authors.lastname: Gao
authors.forename: Yu-Sheng
authors.initials: YS
authors.lastname: Zhang
authors.forename: Xiao-Fan
authors.initials: XF
authors.lastname: Zhang
authors.forename: Cui-Rong
authors.initials: CR
authors.lastname: Zhao
authors.forename: Wen-Fang
authors.initials: WF
authors.lastname: Xu
authors.forename: Qian-Bin
authors.initials: QB
authors.lastname: Li
authors.forename: Jin-Xiang
authors.initials: JX
authors.lastname: Han
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000737:chemistry / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D015153:Blotting, Western; D018826:CD13 Antigens / Q000037:antagonists & inhibitors*; D002455:Cell Division / Q000187:drug effects*; D045744:Cell Line, Tumor; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D007094:Imides / Q000737:chemistry*; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D008958:Models, Molecular; D018716:Molecular Mimicry; D010051:Ovarian Neoplasms / Q000201:enzymology / Q000473:pathology*; D010456:Peptides, Cyclic / Q000737:chemistry / Q000494:pharmacology*; D010880:Piperidines / Q000494:pharmacology*; D011480:Protease Inhibitors / Q000737:chemistry / Q000494:pharmacology*
chemical_list: C549025:2-amino-N-(1-(2-(hydroxyamino)-2-oxoethyl)-2,6-dioxopiperidin-3-yl)-3-phenylpropanamide; D000970:Antineoplastic Agents; D007094:Imides; D010456:Peptides, Cyclic; D010880:Piperidines; D011480:Protease Inhibitors; D018826:CD13 Antigens