{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T12:05:35Z","timestamp":1789992335003,"version":"4.0.1"},"reference-count":51,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T00:00:00Z","timestamp":1789948800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Microbiol."],"abstract":"<jats:p>Gut inflammation associated with colorectal cancer (CRC) is closely linked to gut microbiota dysbiosis and altered microbial metabolites that disrupt intestinal homeostasis. Among these metabolites, indole derivatives produced through microbial tryptophan metabolism have emerged as important regulators of colon health. Recent evidence suggests that indole derivatives can influence gut barrier integrity, colon inflammation, and CRC progression. In this mini-review, we summarize current evidence regarding the role of indole derivatives in gut barrier regulation and CRC development. We also discuss their potential relationship with signaling pathways implicated in CRC progression, particularly the PI3K\/AKT pathway, which may offer new perspectives on improving colon health and preventing inflammation-associated CRC.<\/jats:p>","DOI":"10.3389\/fmicb.2026.1913453","type":"journal-article","created":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T11:13:37Z","timestamp":1789989217000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Gut microbiota-derived indole metabolites in colorectal cancer: potential links to PI3K\/AKT signaling pathway"],"prefix":"10.3389","volume":"17","author":[{"given":"Abrory A. C.","family":"Pramana","sequence":"first","affiliation":[{"name":"Division of Nutritional Sciences, College of Agricultural, Consumer, and Environmental Sciences, University of Illinois","place":["Urbana, IL, United States"]},{"name":"Department of Biochemistry, Faculty of Medicine, Public Health, and Nursing, Universitas Gadjah Mada","place":["Yogyakarta, Indonesia"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alison","family":"Ho","sequence":"additional","affiliation":[{"name":"Department of Food Science and Human Nutrition, College of Agricultural, Consumer, and Environmental Sciences, University of Illinois","place":["Urbana, IL, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Guanying B.","family":"Xu","sequence":"additional","affiliation":[{"name":"Department of Food Science and Human Nutrition, College of Agricultural, Consumer, and Environmental Sciences, University of Illinois","place":["Urbana, IL, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuan-Xiang","family":"Pan","sequence":"additional","affiliation":[{"name":"Division of Nutritional Sciences, College of Agricultural, Consumer, and Environmental Sciences, University of Illinois","place":["Urbana, IL, United States"]},{"name":"Department of Food Science and Human Nutrition, College of Agricultural, Consumer, and Environmental Sciences, University of Illinois","place":["Urbana, IL, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hong","family":"Chen","sequence":"additional","affiliation":[{"name":"Division of Nutritional Sciences, College of Agricultural, Consumer, and Environmental Sciences, University of Illinois","place":["Urbana, IL, United States"]},{"name":"Department of Food Science and Human Nutrition, College of Agricultural, Consumer, and Environmental Sciences, University of Illinois","place":["Urbana, IL, United States"]},{"name":"Cancer Center at Illinois, University of Illinois","place":["Urbana, IL, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,9,21]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","first-page":"716","DOI":"10.1016\/j.chom.2018.05.003","article-title":"Gut microbiota regulation of tryptophan metabolism in health and disease","volume":"23","author":"Agus","year":"2018","journal-title":"Cell Host Microbe"},{"key":"ref2","doi-asserted-by":"publisher","first-page":"1002","DOI":"10.2174\/18715206113139990078","article-title":"Targeted regulation of PI3K\/Akt\/mTOR\/NF-\u03baB Signaling by indole compounds and their derivatives: mechanistic details and biological implications for Cancer therapy","volume":"13","author":"Ahmad","year":"2013","journal-title":"Anti Cancer Agents Med. 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