Grant: Master's Award: Canada Graduate Research Scholarships - Master's program

Each year, 3000 Canadians are diagnosed with ovarian cancer. After treatment, only 15% of patients will survive ten years or more. What makes these long-term survivors different, and what can we learn from them to help more people live longer, healthier lives? Long-term survivors often have lots of immune cells inside their tumours, notably a type of immune cell called tumour-infiltrating B cells (TIL-B). However, it is unclear how TIL-B attack tumours. Normally, B cells release antibodies that travel through the blood to ‘tag’ harmful cells, so other immune cells can recognize and destroy these marked cells. Intriguingly, my research has revealed antibody deposits on ovarian tumours and in the blood vessels that feed them. Does this mean TIL-B are tagging ovarian cancer for destruction? To answer this, I will assess whether TIL-B are linked to anti-tumour antibodies that (a) circulate in the blood, (b) spare healthy tissue and (c) contribute to longer patient survival. In Aim 1, tumour-reactive antibodies will be measured in metastatic HGSC patients by assessing whether antibodies in their serum bind to tumour and blood vessel cells. In Aims 2 and 3, primary and metastatic tumour samples will be examined alongside healthy tissue using immunofluorescent imaging to determine how selectively these antibodies target cancer, and whether TIL-B, other immune cells and anti-tumour antibodies are more common in long-term survivors. This research will address a critical gap in understanding how the immune system uses circulating anti-tumour antibodies to battle the spread of metastatic cancer. Ultimately, this work aims to guide the development of new antibody-based immunotherapies, so that long-term survival becomes the norm, not the exception.