Irene Cafferati

Introduction: Individuals with Familial Adenomatous Polyposis (FAP) or APC-associated polyposis, an autosomal dominant inherited condition, develop multiple adenomatous polyps and have an increased colorectal cancer (CRC) risk. A change in diet can help reduce cancer risk, and several dietary components have an antitumor effect. We aimed to evaluate the potential of the anti-inflammatory and anticancer substances quercetin (QER), epigallocatechin gallate (EGG) and fisetin (FIS) in decreasing the risk of CRC by reducing the growth of polyps in an organoid model. Methods: Patient-derived organoid (PDO) lines were generated from polyps obtained from patients with FAP undergoing prophylactic colectomy. PDOs were treated with QER, EGG, or FIS to determine their effect on cell growth. Changes in caspase 3/7 activity and expression of inflammation and apoptosis mediators were assessed by luminescent and colorimetric assays. Results: Three PDO lines with different inactivating pathogenic variants in the APC gene were developed using a combinatorial approach. FIS was the most active of the three substances tested, presenting the lowest IC50 in all PDO lines (range: 42.6-9.2 uM). The IC50 was defined as the concentration required to halve the number of cells after 72 hours. All molecules tested induced apoptosis through activation of caspases 3/7. Conclusions: QER, EGG, and FIS can be easily taken from foods or dietary supplements, show toxicity on PDOs derived from adenomatous polyps, while they are known to be harmless on normal cells. Diets enriched with these substances could be potential supplemental treatments to reduce the risk of CRC in individuals with FAP.