doi:10.1002/cpt.639engPatrignani, PSacco, ASostres, CBruno, ADovizio, MPiazuelo, EDi Francesco, LContursi, AZucchelli, MSchiavone, STacconelli, SPatrono, CLanas, A.Low-dose aspirin acetylates cyclooxygenase-1 in human colorectal mucosa: implications for the chemoprevention of colorectal cancer.ART-2017-97965The mechanism of action of low-dose aspirin in the prevention of colorectal cancer (CRC) remains largely hypothetical. We aimed to compare the effects of low-dose aspirin (100 mg/day for 7 days) given to 40 individuals undergoing CRC screening on the extent of cyclooxygenase (COX)-1 acetylation at serine-529 (AceCOX-1), in blood platelets vs colorectal mucosa, at 7 (group 1) and 24 hours (group 2) after dosing. A significantly (P<0.01) lower %AceCOX-1 was detected in colonic and rectal mucosa (average 64%) vs platelets (average 75%) in both groups. This effect was associated with an average 46% (P<0.01) and 35% (P<0.05) reduction in prostaglandin (PG) E2 levels and phosphorylated S6 (p-S6) levels, respectively. Rectal mucosal levels of p-S6/S6 significantly(P<0.01) correlated with PGE2. These findings demonstrate that low-dose aspirin produces long-lasting acetylation of COX-1 and down-regulation of p-S6 in human colorectal mucosa, an effect that may interfere with early colorectal carcinogenesis.2017http://zaguan.unizar.es/record/6449610.1002/cpt.639http://zaguan.unizar.es/record/64496oai:zaguan.unizar.es:64496CLINICAL PHARMACOLOGY & THERAPEUTICS 36 (2017), [29 pp.]All rights reservedhttp://www.europeana.eu/rights/rr-f/info:eu-repo/semantics/openAccess