BRAF, A gatekeeper controlling endothelial permeability.

The RAF/MEK/ERK signal transduction pathway is commonly deregulated in cancer and is activated by various stimuli regulating a variety of cell responses. In wild-type endothelial cells, upon permeability stimuli, ROKα, RAF1, BRAF, and RAP1 become activated, inducing a cascade of reactions resulting in F-actin remodeling and increased cell permeability. Here, Dorard et al. showed that BRAF ablated cells had more RAF1/ROKα dimerization and relocalization to VE-cadherin occurred, ultimately leading to less F-actin content and reduced vessel permeability.