Metastatic breast cancer hitches a free ride from the immune system

Inflammatory breast cancer (IBC) spreads easily through the lymphatic and blood vessels, forming deadly metastasis. New research demonstrates how IBC cells use IL-8, a compound secreted as part of the anti-inflammatory response by a specific set of white blood cells (monocytes), to increase fibronectin expression. Fibronectin is a cell-adhesion molecule usually involved in wound healing and cell migration, but over-expression of this molecule is thought to allow cancer to metastasize. Prof Mona Mohamed from Cairo University used a cytokine antibody array to identify which immune-regulating molecules were secreted by monocytes and found that, while monocytes secreted a small amount each of a wide range of molecules, there was up to 10 times more IL-8 and MCP-1. The cocktail of immune-regulating molecules from the monocytes was able to increase the amount of fibronectin produced in IBC cells and in 3D culture produced branch-like structures typical of fibronectin over-expression.