Grant: Canada Postdoctoral Research Award (CPRA) program

Despite advances in smoking prevention programs, CT imaging, and targeted therapies, lung cancer remains a major public health challenge in Canada, with only 19% of patients surviving five years after diagnosis. Improvement in early detection and new treatment strategies are urgently needed to change this outcome. A promising but underexplored avenue is the lung microbiome (the community of bacteria that live in the lungs). Research from our group and others have shown that certain bacteria can supply nutrients and metabolites that cancer cells cannot produce themselves. In this way, tumours may "feed" on bacterial by-products to fuel their growth. This discovery has created opportunities for earlier diagnosis and treatment. For early diagnosis, shifts in the lung microbiome composition have been observed more than a year before a formal diagnosis of lung cancer. Identifying a reliable airway bacterial "signature" could lead to a simple, non-invasive test for early detection, particularly in high-risk groups such as current and former smokers or those with chronic lung disease. Using a unique collection of samples from smokers followed for over 10 years, we track bacterial changes over time in individuals who developed lung cancer and those who remained cancer-free. For a novel treatment strategy, we will test whether blocking access to the bacteria-made nutrients can slow or "starve" tumour cells. We will evaluate whether disrupting this microbial fuel supply can form the basis of new therapeutic strategies - by eliminating (a) bacterial production using microbial inhibitors, and (b) preventing tumour cells from using these bacterial nutrients by blocking the pathways they use to take them up. Together, these approaches aim to deliver accessible tools for earlier diagnosis and innovative treatments, ultimately improving outcomes and quality of life for Canadians at risk of or affected by lung cancer.