Protein removal may slow blood vessel, tumor growth
Scientists have discovered a new protein which triggers the growth of blood vessels in breast cancer tumors that have spread to the brain, a common location for breast cancer to metastasize. These findings were published in Nature Communications (2015; doi:10.1038/ncomms8286). Withholding the DOCK4 protein in mouse models led to a particular part of the blood vessel not forming as quickly, and so tumors grew at a slower rate.
"The finding gives an important indicator of how the protein affects the growth of secondary breast tumors in the brain,” said Georgia Mavria, PhD, of the University of Leeds in the United Kingdom. “The discovery could also enable experts to predict which patients might be at risk of their breast cancer spreading, and develop drugs to prevent the growth of secondary tumors."
Working with Professor Chris Marshall, DPhil, Professor of Cell Biology at The Institute of Cancer Research in London and the late Tony Pawson, PhD, at the Lunenfeld-Tanenbaum Research Institute in Toronto, Canada, researchers found that a complex of two related proteins, DOCK4 and DOCK9, is critical in the formation of the lumen, the interior space of a vessel through which blood flows.
By impeding the speed at which the lumen forms, tumors are not fed as effectively by blood vessels.
Normally, when breast cancer spreads to other parts of the body, it forces new blood vessels to form to supply it with nutrients and oxygen to help it to grow, resulting in tumors that are very difficult to treat.
"Our study reveals new insights into how the complex process of forming blood vessels is controlled,” said Marshall. “This knowledge could lead to new approaches to preventing the blood supply to tumors and metastases. If we can find new ways to reduce the blood supply to tumors, we might be able to find new ways to slow cancer growth in future."The research was funded by Breast Cancer Now, Yorkshire Cancer Research, and Cancer Research UK.