Cancer-associated fibroblasts as key regulators of lipid metabolism in the tumour microenvironment.

Alterations in metabolism are recognised as a hallmark of cancer, allowing for rapid proliferation in an environment often hypoxic and short of nutrients. Cells within the tumour microenvironment (TME) often undergo metabolic alterations to adapt to these conditions, and this can also contribute to tumour progression. Cancer associated fibroblasts (CAFs) are amongst the most abundant non-cancerous cells in the TME and the main cells responsible for production and maintenance of the extracellular matrix. However, CAF subtypes can impact tumours in different ways and have been shown to play a role in alterations to lipid metabolism within tumours, being able to produce and secrete lipids, internalise them from the surrounding environment, and undergo fatty acid oxidation. Whilst this is still an emerging area of research, it appears that CAFs can have opposing roles in lipid metabolism in different types of cancer. Understanding the different metabolic pathways utilised in both CAFs and cancer cells and how external factors such as obesity and high fat diets influence them, could provide novel treatment avenues in the future. This review explores the literature surrounding lipid metabolism in CAFs and how this influences tumour progression and treatment resistance.