Grant: Banting Postdoctoral Fellowship Program

Metastatic triple negative breast cancer (mTNBC) is an aggressive form of the disease with limited therapeutic options. Immunotherapy, a type of therapy that uses the patient's own immune system to target and kill cancer cells within the body, has shown promise for aggressive and difficult to treat tumours. Unfortunately, only ~10% of mTNBC patients benefit from immunotherapy treatments. In order to design better therapies for mTNBC patients that can harness the patient's immune system to kill the cancer within them, we first need a better understanding of the underlying interactions between different immune cells in that cancer. Recent studies have shown that the presence of B cells in TNBC are predictive of improved outcomes. However, nothing is known about their relevance in metastatic disease. Additionally, extensive clinical documentation shows a negative impact of myeloid cells within the tumour, though little is known about how they affect other cell types. In our proposed studies, we will investigate the impact of myeloid cells on B cells frequency and function as well as their role in the organization of immune cells within both primary and metastatic tumours from TNBC patients. These studies will allow us to delineate the prognostic relevance of B cells in mTNBC so that we may better identify which patients can benefit from immunotherapy treatments. We can also use this information to design novel targeted therapies for mTNBC patients. Using human samples and a mouse model of mTNBC allows us to identify and assess B cell subsets within human samples and investigate how they are affected by myeloid cells in murine models. This work will fill a critical void in the field and improve our knowledge for clinical management of mTNBC.