To determine whether systemic inhibition of PI recycling preferentially reduces pro-angiogenic signaling in tumor-associated ECs but not in quiescent endogenous ECs, we analyzed ECs from both tumors (Fig. 4e–i, o–q) and from livers/lungs (Fig. 4j–n, r–t) of the same Cds2 vMO (Fig. 4e–n) or L-690,488 (Fig. 4o–t) treated, LLC-allografted mice using immunostaining and western blot analysis. Here, CDS2 is linked to neoplasm.