RECENT research indicates that long-term, daily use of aspirin decreases both the incidence and mortality of colorectal cancer (CRC). The study in question, a retrospective cohort study, found that aspirin may act as a protective agent against CRC by enhancing immunosurveillance.
To examine the effects of regular aspirin use on CRC, researchers obtained tissue samples from a total of 238 patients who had undergone surgery for CRC between 2015–2019, 12% of whom were regular users of aspirin. Comparing the data between regular aspirin users and non-aspirin users, the former demonstrated fewer cases of secondary lymphomas, and increased influx of immune cells into tumours.
Analysis of messenger RNA expression of immunosurveillance-linked genes in CRC cell lines, derived from the Gene Expression Omnibus (GEO)-deposited public database (GSE76583), indicated enhanced expression of CD80 protein on immune cells. Heightened expression of this protein was evidenced to increase the cell-signaling capacity of immune cells, enabling them to alert other immune cells to the presence of tumour-specific antigens. In addition to these findings, researchers identified increased expression of CD80 protein in healthy rectal tissues in regular users of aspirin, highlighting enhanced immune surveillance in this cohort.
Despite the promising findings of this study, corresponding author Marco Scarpa, University of Padova, Italy, highlights a fundamental consideration, stating that, due to the nature of absorption along the bowel and in the rectum, “the concentration of orally-administered aspirin can be much lower than in the rest of the colon. Thus, if we want to take advantage of its effects against CRC, we should think of how to guarantee that aspirin reaches the colorectal tract in adequate doses to be effective.”
Looking to the future, this study represents a significant step in our understanding of CRC, its prevention, and its treatment. Where aspirin is classically used in the alleviation of inflammation and, to a lesser extent, in the prevention of various cardiovascular events, it now boasts potential therapeutic use in the treatment of CRC. Additionally, it may represent a potential preventative agent in those most at risk of developing CRC.
Reference:
Ottavia De Simoni et al. IMMUNOREACT 7: regular aspirin use is associated with immune surveillance activation in colorectal cancer. Am Canc Soc. 2024;DOI: 10.1002/cncr.35297.
