Metastasis is the process by which tumour cells leave a tumour to start growing at other locations in the body. While many brain and breast cancers are cured through a combination of surgery and chemotherapy or radiation therapy, metastatic disease is frequently incurable.
Since the discovery of cancer-causing genes, decades ago, there has been a great deal of progress on defining how individual proteins either promote or suppress cancer. Despite this, the metastatic process has remained somewhat mysterious.
For some types of cancer, the original tumour is quite similar to its metastatic descendants. Typically, this is true for colon cancer, pancreatic cancer and lung cancer. Although many challenges remain, at least for these tumour types, novel therapies based on properties of the primary tumour have an excellent chance of killing metastatic lesions as well. In contrast, breast cancer and the childhood brain tumour, medulloblastoma, pose a remarkable and difficult additional challenge in that the original tumour and its metastases are frequently very different. This means that therapy directed against the primary tumour has little chance of killing the metastastic growths.
With this information in hand we have chosen a new tack. We have designed experiments, using state-of-the-art technologies, to identify the small number of cancer-causing pathways that are shared by primary tumours and their metastases. We are doing this for both breast cancer and medulloblastoma. Once identified, we will determine which of the shared pathways, when shut down, have the best chance of killing local and metastatic disease.
This new idea, which takes advantage of sophisticated DNA sequencing technology to find all needles in the haystack, by identifying not just one cancer-causing mutation in a breast or brain tumour, but all of them, as well as approaches that allow us to switch on and off particular genes and follow the effect of this in both the primary cancer and the secondary growths. By defining the complete network of cancer-causing mutations common to both primary tumours and metastasis,