Anti-angiogenic therapy has immense clinical potential to not only impede tumor growth but also to inhibit tumor metastases. The first small molecule anti-angiogenic agent to enter clinical trials was the fumagillin derivative, TNP-470 (AGM1470), despite a limited knowledge of its mode of action. Our long-term goal is the exploration of TNP-470's molecular mechanism of action and the application of this information in the development of novel anti-angiogenic agents. We previously identified methionine aminopeptidase 2 (MetAP2) as the direct binding protein of fumagillin, and demonstrated that TNP-470 functions via p53 and p21 to induce its G, cell cycle arrest. To understand better the role of MetAP-2 in angiogenesis, we have generated a null-MetAP-2 and several MetAP-2-conditional knockout mouse lines. We have shown that induced loss of MetAP-2 in the endothelium results in an embryonic lethality at a similar developmental stage observed when other proteins known to be important in angiogenesis are required. Interestingly, complete loss of MetAP-2 results in an earlier embryonic lethality and defective gastrulation. We have subsequently shown that TNP-470 treatment or MetAP-2 knock down (via antisense morpholino oligonucleotides) in zebrafish result in a cell morphogenetic defect identical to misregulation of a non-canonical Wnt signaling pathway. This is consistent with the previously reported finding in Drosophila that MetAP-2 loss of function mutation results in ommatidial rotation defects and loss of ventral tissue in the eye, which is another phenotype indicative of defects in the non-canonical Wnt planar cell polarity (PCP) pathway. These genetic results strongly suggest that the non-canonical Wnt signaling pathway is regulated by TNP-470 via inhibition of MetAP2. In this study, we plan to characterize adult MetAP-2 KO mice histologically, behaviorally, and, in particular, for their angiogenic and tumor-bearing potential. We also plan to study the role that MetAP-2 plays in the non-canonical Wnt pathway and the importance of this pathway in endothelial cell growth control. Finally, we plan to identify and validate downstream MetAP-2 substrates. The combination of biochemical and cell culture approaches in the murine models provides a unique opportunity to characterize the relevant step or target for TNP-470 anti-angiogenesis intervention. The information generated from this study will contribute new information regarding angiogenic regulation and may provide new targets for the development of additional anti-angiogenic agents
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