NRP2 and cancer: NRP1flflNRP2flfl.ECKO PyMT-BO1 tumors were found to be approximately 70% less vascularized than respective Cre-negative control tumors (Fig. 3M and N; Supplementary Fig. S2A and S2B), corroborating our CMT19T studies, and confirming that the expression of NRP1 and NRP2 is essential for tumor angiogenesis in multiple cancer models.