Endothelial deletion of the neddylation E2 enzyme UBE2M inhibits tumor growth by promoting non-productive angiogenesis.

Abstract

Neddylation is highly activated in many human cancers and may serve as a therapeutic target for clinical treatment. However, it remains unclear regarding the role of neddylation in tumor angiogenesis. Here, we demonstrate that the neddylation E2 enzyme UBE2M is upregulated in tip cells and is essential for tumor vascular sprouting. We show that UBE2M-mediated neddylation of STAT1 enhances its phosphorylation and promotes the transcription of DLL4. This elevated DLL4 expression in tip cells activates Notch signaling in adjacent stalk cells, thereby maintaining the tip-stalk cell balance and ensuring organized vascular patterning. Consequently, endothelial-specific deletion of UBE2M reduces DLL4 expression, leading to excessive but non-productive sprouting due to uncontrolled tip cell formation and lack of stalk cell support, which ultimately suppresses tumor growth. Importantly, targeting endothelial neddylation potently sensitizes various tumors to anti-VEGF therapy. Together, our findings unveil UBE2M as a key regulator of angiogenic signaling and identify it as a promising anti-angiogenic target in cancer.