(IMAGE) Tokyo Medical and Dental University Caption Usually, blood vessels are stabilized, and their barrier function is maintained by the tight adhesion between vascular endothelial cells (①). When cancer cells metastasize to distant organs via blood vessels, the morphology of vascular endothelial cells changes in response to the growth factors or cytokines secreted by the cancer cells. This results in the loss of adhesion between vascular endothelial, destabilization of the vessels and loss of their barrier function. These changes facilitate invasion, “intravasation" (②) of cancer cells into blood vessels and allow the cancer cells to travel through the body in the bloodstream. When cancer cells reach the distant organs, they migrate out of the blood vessels in a process called "extravasation" (③) by inducing vascular destabilization, followed by formation of distant metastatic sites. Credit Department of Biochemistry, TMDU Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.