Arrest of B16 melanoma cells in the mouse pulmonary microcirculation induces endothelial nitric oxide synthase-dependent nitric oxide release that is cytotoxic to the tumor cells.

Metastatic cancer cells seed the lung via blood vessels. Because endothelial cells generate nitric oxide (NO) in response to shear stress, we postulated that the arrest of cancer cells in the pulmonary microcirculation causes the release of NO in the lung. After intravenous injection of B16F1 melanoma cells, pulmonary NO increased sevenfold throughout 20 minutes and approached basal levels by 4 hours.