Blood clot

Link between high levels of blood clotting protein and poorer breast cancer outcomes

  • Research

One in five patients with cancer develop blood clots which can be serious, life-threatening and even fatal. As there are over 2 million people worldwide diagnosed with breast cancer every year, it is not only the world’s most prevalent cancer but also most commonly associated with these life-threatening blood clots.

For the first time, new research from RCSI has provided insight into how breast cancer tumour cells may cause this increase risk of blood clotting to occur and how this may contribute to breast cancer spread throughout the body. The findings will help researchers and doctors to better understand and treat breast cancer to reduce the risk of life-threatening blood clots and may help identify new treatments to help reduce cancer spread in patients and thus improve survival.

Published in the Journal of Thrombosis and Haemostasis, the research found that patients with breast cancer had very high levels of a key protein involved in blood clotting called von Willebrand Factor in their bloodstream and that these patients had the poorest outcomes. This work suggests that analysis of von Willebrand Factor levels may be useful to help predict clinical outcomes in patients with breast cancer.

The study also examined how breast cancer triggers high levels of von Willebrand Factor and found that breast tumour cells cause release of the clotting protein directly from the blood vessels which helps the breast tumour cells to circulate in the bloodstream.

Anticoagulant medication or blood-thinners which are already used to treat blood clots could inhibit this effect by reducing levels of von Willebrand Factor and also preventing the spread of cancer cells in the bloodstream.

The findings of the research will help doctors to better understand why patients with breast cancer have increased risk of blood clots and also why this may contribute to worse disease, cancer progression and spread throughout the body.

The research was conducted by the Irish Centre for Vascular Biology, School of Pharmacy and Biomolecular Sciences, RCSI, in collaboration with Cellular and Molecular Imaging Core, RCSI and Manchester Cancer Research Centre, The University of Manchester, UK.

The research was funded by LEO Pharma through an industry partnership with the Irish Research Council.


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