Human breast cancer cells that overexpress Notch (green) lose E-cadherin (red) and metastasize.
Breast cancer cells grow aggressively and enter the circulation when they stop expressing E-cadherin, which glues cells together. E-cadherin is suppressed by Notch signaling in some cell types during periods of development, when cells need to move around to form three-dimensional organs.
Increased levels of Notch and its ligand Jagged are found in breast cancer patients who have malignant tumors and are therefore less likely to survive. Leong et al. now find that Notch activation by Jagged frees cancer cells by shutting off their E-cadherin glue.
When Notch receptor levels were increased in E-cadherin–expressing human breast cancer cells, the cells turned on...
