biostudies-literatureArima KCancer Research UKNIDDK NIH HHSNCI NIH HHS862-874https://www.ebi.ac.uk/biostudies/studies/S-EPMC9509428biostudies-literatureUnknown163(4)<h4>Background & aims</h4>Evidence supports a carcinogenic role of Escherichia coli carrying the pks island that encodes enzymes for colibactin biosynthesis. We hypothesized that the association of the Western-style diet (rich in red and processed meat) with colorectal cancer incidence might be stronger for tumors containing higher amounts of pks⁺E coli.<h4>Methods</h4>Western diet score was calculated using food frequency questionnaire data obtained every 4 years during follow-up of 134,775 participants in 2 United States-wide prospective cohort studies. Using quantitative polymerase chain reaction, we measured pks⁺E coli DNA in 1175 tumors among 3200 incident colorectal cancer cases that had occurred during the follow-up. We used the 3200 cases and inverse probabiliGastroenterologyWestern-Style Diet, pks Island-Carrying Escherichia coli, and Colorectal Cancer: Analyses From Two Large Prospective Cohort Studies.PMC9509428K07 CA188126R35 CA197735U01 CA167552K24 DK098311R01 CA137178P01 CA087969K07 CA19067327140UM1 CA167552R01 CA118553R35 CA253185R01 CA151993P01 CA055075P50 CA127003R01 CA169141P30 DK043351UM1 CA186107Wu KKosumi KSears CLWillett WCGiovannucci ELShi SWang FLau MCVayrynen JPArima KZhao MOgata YSong MAkimoto NFujiyoshi KHaruki KOkadome KBaba HChan ATGiannakis MTwombly TSHuttenhower CUgai TKishikawa JOgino SMehta RSZhong RZhang XFuchs CSGarrett WSMeyerhardt JANowak JAfalseWestern-Style Diet, pks Island-Carrying Escherichia coli, and Colorectal Cancer: Analyses From Two Large Prospective Cohort Studies.<h4>Background & aims</h4>Evidence supports a carcinogenic role of Escherichia coli carrying the pks island that encodes enzymes for colibactin biosynthesis. We hypothesized that the association of the Western-style diet (rich in red and processed meat) with colorectal cancer incidence might be stronger for tumors containing higher amounts of pks⁺E coli.<h4>Methods</h4>Western diet score was calculated using food frequency questionnaire data obtained every 4 years during follow-up of 134,775 participants in 2 United States-wide prospective cohort studies. Using quantitative polymerase chain reaction, we measured pks⁺E coli DNA in 1175 tumors among 3200 incident colorectal cancer cases that had occurred during the follow-up. We used the 3200 cases and inverse probabili2022-01-01T00:00:00Z2022 Oct2025-04-18T23:53:28.029Z2025-04-07T11:13:24.666ZS-EPMC95094283576008610.1053/j.gastro.2022.06.054