Project 444825

Lay Abstract: Breast cancer remains a leading cause of mortality of women in Canada and worldwide. Dietary factors including fatty acids are increasingly recognized for their role in preventing or promoting breast cancer. Omega-3 fatty acids are the most promising anticancer nutrients. However, there remains much confusion over the best form of omega-3 fatty acids. While the plant-based form, found in flax, soy and canola, is abundantly consumed in N. American diets, much of the research has focused on omega-3 fatty acids found in fish oil. Furthermore, the potential benefits and mechanisms by which omega-3 fatty acids protect against different types of breast cancers are poorly understood. Therefore, the overall objective is to strengthen our confidence that omega-3 fatty acids are protective against breast cancer. This will be done in two ways by defining mechanisms of action and generalizing these effects in different breast cancers. Mechanistic studies are vital to providing biological insights relevant to humans. Thus, this knowledge is key to advancing our approach to cancer prevention. Overall, this work has value answering a practical question posed by researchers and the public, "Which is better: omega-3's from plants or seafood and for what types of cancers?" Answering these questions will contribute to the translation of preclinical research to human studies and practical applications.