Targeting lung-derived proteins as a therapeutic strategy against breast cancer metastasis
Dr. Alison Allan, Senior Oncology Scientist, London Regional Cancer Program
If breast cancer is detected early, traditional surgical and radiation therapy approaches have a high success rate, but once the disease spreads (or metastasizes) beyond the breast, many conventional treatments fail. In particular, the lung is one of the most common and deadly sites of breast cancer metastasis and this has a significant impact on patient quality of life and survival. Treatment of metastasis is often done by delivering drugs to the whole body, causing toxic side effects. However, unlike other metastatic sites the lung has the unique potential to be targeted directly by delivering drugs via inhalation, an approach that has been used in the treatment of respiratory diseases but remains under-explored in oncology. We have previously observed that aggressive breast cancer cells expressing a protein called CD44 on their cell surface are responsible for metastasis. Importantly, we have shown that these CD44+ cancer cells have a particular propensity for migrating (traveling to) and growing in the lung through specific interactions with proteins produced by the lung itself. In this project, my research team aims to understand the interactions between CD44+ breast cancer cells and CD44-interacting proteins produced by the lung microenvironment in order to determine how this helps migration and growth in the lung as part of the metastatic process. We are investigating whether we can use an inhaled drug delivery approach to directly inhibit CD44-interacting proteins in the lung as an effective strategy for reducing breast cancer metastasis as well as toxic side effects. By gaining a greater understanding of the underlying biology and therapeutic potential of lung-derived factors in breast cancer metastasis, we have the potential to positively impact breast cancer patient survival in the future.