We have identified several genes that regulate the metastatic process. By understanding how these genes act to control metastasis, we can develop effective therapies which directly target these genes or other genes controlled by these metastasis regulators. Another important aspect of our research is to examine human breast cancer tissues for evidence that the gene identified in our preclinical models is also relevant in the human disease.

Metastasis Regulating Genes

We have shown that some of the genes we have identified, including caveolin-1, microRNA-200 and BMP4, are able to suppress metastasis. With BMP4, we have found that its metastasis suppressing activity is in part through the inhibition of G-CSF, which controls the mobilisation and differentiation of neutrophils. In the presence of a tumour, the activity of neutrophils can be changed from infection fighting to supporting the spread of cancer cells to other organs, such as the lung. This led to our demonstration in our preclinical models that blocking the mobilisation of neutrophils can reduce metastasis. We are now probing more deeply to understand how neutrophil function is altered by factors released from tumours and the relevance of this to patients with breast cancer.

Much of our research is focused on immune regulation of metastasis by the innate immune system (including macrophages and neutrophils), but some of the other genes we have identified appear to act directly on the tumour cells to prevent their ability to metastasise.

Metastatic Dormancy

Breast cancer is noted for the long latency between diagnosis and therapy for the primary cancer and development of secondary cancers, which can cause ongoing anxiety for patients fearing a recurrence. We are investigating how tumour cells can disseminate from the primary tumour and remain alive but clinically undetectable for many years, and how they start expanding into life-threatening cancers in some patients. We are seeking therapies that prevent the expansion of these dormant cancer cells into new tumours.

Drug Discovery and Delivery

We have collaborated with Dr Ian Street and the Walter and Eliza Hall Institute drug discovery team to identify small molecules that can be developed into drugs to combat metastatic disease. We also work with the ARC Centre of Excellence in Convergent Bio-Nano Science and Technology (Monash University) to improve drug delivery to tumours using nanoparticle technology.