This research was funded by the Italian Association for Cancer Research (AIRC), grant IG17413 to SP. The assistant position (RTDa) of SA is fully supported by the University of Trieste, in agreement with the actuation of the strategic planning financed by the Italian Ministry for University and Research (MIUR, triennial program 2016–2018) and the Regione Friuli Venezia Giulia (REFVG, strategic planning 2016-18), assigned to SP. This award is deeply acknowledged.