Cysteinyl leukotriene 2 receptor promotes endothelial permeability, tumor angiogenesis, and metastasis

Significance Cysteinyl leukotrienes (cys-LTs) are proinflammatory mediators and regulate endothelial cell contraction, permeability, and angiogenesis via a cys-LT receptor, CysLT2 R. In response to the challenges of finding therapies that can combat tumor angiogenesis and metastases, we explored the advantage of targeting this receptor. We show that CysLT2 R mediates tumor angiogenesis and contributes to metastasis in vivo independent of VEGF by enhancing leakiness and permeability of blood vessels. We propose that a CysLT2 R antagonist, BayCysLT2 , can normalize vessels, reducing tumor growth and metastasis.