Distant metastasis reduced by oxidative stress

Although solid cancer cells such as melanoma cells readily enter the circulation system, they are not very efficient at forming metastases at sites away from the original tumour. Sean Morrison and colleagues show that human melanoma cells grown in mice experience high levels of oxidative stress in the bloodstream, such that few metastasizing cells survive to form tumours. The rare melanoma cells that do successfully metastasize undergo metabolic changes that increase their capacity to withstand this stress. Antioxidant treatments increase metastasis by human melanoma cells, while inhibiting antioxidant pathways has the opposite effect.