PLAU and neoplasm: Since the very first description of the receptor for the urokinase plasminogen activator (uPAR) in 1985 [1], a large amount of works have identified the urokinase plasminogen activator system as the mediator of many aspects of cancer cell malignancy, modulating numerous signaling events, cell survival, invasion and migration, angiogenesis and intra-tumor recruitment of inflammatory cells [2,3,4].