Can Aspirin protect against skin cancer?
Aspirin (acetylsalicylic acid) is an interesting and versatile drug. Its main indication for many years has been in pain reduction by COX-2 inhibition (preventing the release of prostaglandins). Research over the years has highlighted the additional benefits of taking the drug. Its antiplatelet properties have been known for some time and it is still extensively used in the prevention of arterial thrombosis - the main cause of heart attacks and strokes . In addition, there have been numerous reports on its effects in the prevention of certain types of cancer (breast, prostate and gastric) and particularly colorectal cancer [2, 3].
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This year a paper has been published in the prestigious Journal of Investigative Dermatology which reports that regular aspirin use can help protect both melanocytes and keratinocytes from Ultraviolet Radiation (UVR) damage . When the skin is exposed to quantities of UVR there is a myriad of mechanisms that may promote skin cancer including DNA damage, oxidative stress, immune-suppression, inflammation, and micro-signalling. Chronic inflammation generally has long been recognised as a risk factor for carcinogenesis and UVB exposure is known to cause the appearance of mutagenic products such as cyclopyrimidine dimers (CPDs) and [6,4]- photoproducts in the DNA of keratinocytes and melanocytes in the skin .
The authors of the study propose that the ensuing inflammation arising after UVB exposure is a particular factor in carcinogenesis. Consequently, they suggest anti-inflammatory agents could be key in reducing these negative effects. They demonstrated that aspirin reduced the amount of inflammation and subsequent damage as measured by a reduction in known chemical agents detected in sunburn.
The research is a starting point, in which more work is required to see if the effect translates to human models. If it does, then development work will be needed at potential topical or systemic drugs that may be used – potentially in those groups at high risk of developing keratinocyte skin cancers such as squamous cell carcinoma.
1. Schrör K. Aspirin and platelets: the antiplatelet action of aspirin and its role in thrombosis treatment and prophylaxis. Semin Thromb Hemost. 1997;23(4):349-56.
2. Cuzick J, Otto F, Baron JA, Brown PH, Burn J, Greenwald P, et al. Aspirin and non-steroidal anti-inflammatory drugs for cancer prevention: an international consensus statement. Lancet Oncol. 2009 May;10(5):501-7.
3. Rothwell PM, Wilson M, Elwin CE, Norrving B, Algra A, Warlow CP, et al. Long-term effect of aspirin on colorectal cancer incidence and mortality: 20-year follow-up of five randomised trials. Lancet. 2010 Nov 20;376(9754):1741-50.
4. Rahman H, Kumar D, Liu T, Okwundu N, Lum D, Florell SR, et al. Aspirin Protects Melanocytes and Keratinocytes against UVB-Induced DNA Damage In Vivo. J Invest Dermatol. 2021 2021/01/01/;141(1):132-41.e3.
5. D’Orazio JA. Aspirin’s Protective Effects Highlight the Role of Inflammation in UV-Induced Skin Damage and Carcinogenesis. J Invest Dermatol. 2021 2021/01/01/;141(1):10-11.