Promotion of metastasis by hypoxic tumour cells

Nine out of ten Canadians who are killed by cancer die because their tumour has metastasized, or spread, to other parts of their body. Metastasis occurs when tumour cells escape from the original, or primary, tumour and then grow into life-threatening metastatic tumours in other organs. Despite the fact that thousands of tumour cells can escape from a primary tumour every day, most cells do not live long enough to grow into metastatic tumours. As well, metastatic tumour cells can only grow in specific organs. Most primary tumours contain cells at lower oxygen levels than normal tissues, and these low-oxygen tumour cells make tumours more aggressive and metastatic.

Based on these facts, Dr. Bennewith's team is developing new approaches to help identify tumours that contain low-oxygen tumour cells in patients. In addition, Dr. Bennewith and his colleagues have recently discovered that proteins made by low-oxygen tumour cells cause the body's normal bone marrow cells to enter the bloodstream and build up in specific organs. These cells create an environment where metastasizing tumour cells can survive and grow into metastatic tumours. Dr. Bennewith’s team intends to identify the specific proteins that control bone marrow cell behavior in order to develop targeted therapies that will prevent the build-up of bone marrow cells in organs and thus inhibit metastatic tumour growth. Metastatic tumours are very difficult to treat, but by studying how tumour cells spread and grow into tumour metastases, more effective cancer treatments can be designed. Dr. Bennewith's expertise in metastasis research combined with his unique research program will improve our understanding of how low-oxygen tumour cells promote metastasis. Importantly, his work will help to create more effective methods to both detect and to treat metastatic cancer in the clinic.