Metformin, aspirin, and colorectal cancer outcomes

Abstract

Colorectal cancer is the second most incident cancer in men and women in Ireland and is the third greatest cause of cancer death. Metformin and aspirin, two drugs which are commonly used in type 2 diabetes and cardiovascular disease, have been identified as having a potential role in the treatment of colorectal cancer. Preclinical studies have demonstrated an inhibitory effect on colorectal tumours with each drug, and a range of potential mechanisms of action for their anti-cancer effects have been proposed. Metformin may act to inhibit colorectal tumours through direct actions on cancer cells or may have an indirect effect through insulin-related signalling pathways. Similarly, aspirin may have a direct effect by inhibiting the COX-2 enzyme in cancer cells, or may act to prevent tumour spread through mechanisms related to platelet inhibition.