ANPEP and neoplasm: Classically, it is widely recognized that canonical RECK is involved in suppression of tumor invasion, angiogenesis and metastasis, in part, by negatively regulating at least three MMPs, namely: MMP-9, MMP-2 and MT1-MMP [9–12], as well as the extracellular metalloproteinases ADAM10 and CD13/aminopeptidase N [13, 14].