title: A miRNA signature for an environmental heterocyclic amine defined by a multi-organ carcinogenicity bioassay in the rat.
abstract: Heterocyclic amines (HCAs) produced during high-temperature cooking have been studied extensively in terms of their genotoxic/genetic effects, but recent work has implicated epigenetic mechanisms involving non-coding RNAs. Colon tumors induced in the rat by 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) have altered microRNA (miRNA) signatures linked to dysregulated pluripotency factors, such as c-Myc and Krüppel-like factor 4 (KLF4). We tested the hypothesis that dysregulated miRNAs from PhIP-induced colon tumors would provide a "PhIP signature" for use in other target organs obtained from a 1-year carcinogenicity bioassay in the rat. Downstream targets that were corroborated in the rat were then investigated in human cancer datasets. The results confirmed that multiple let-7 family members were downregulated in PhIP-induced skin, colon, lung, small intestine, and Zymbal's gland tumors, and were associated with c-myc and Hmga2 upregulation. PhIP signature miRNAs with the profile mir-21high/mir-126low/mir-29clow/mir-215low/mir-145lowwere linked to reduced Klf4 levels in rat tumors, and in human pan-cancer and colorectal cancer. It remains to be determined whether this PhIP signature has predictive value, given that more than 20 different genotoxic HCAs are present in the human diet, plus other agents that likely induce or repress many of the same miRNAs. Future studies should define more precisely the miRNA signatures of other HCAs, and their possible value for human risk assessment.
authors.affiliation: Center for Epigenetics and Disease Prevention, Texas A&M University College of Medicine, 2121 W Holcombe Blvd., Houston, TX, 77030, USA.
authors.forename: Ying-Shiuan
authors.initials: YS
authors.lastname: Chen
authors.affiliation: Linus Pauling Institute, Oregon State University, Corvallis, OR, USA.
authors.forename: Rong
authors.initials: R
authors.lastname: Wang
authors.affiliation: Center for Epigenetics and Disease Prevention, Texas A&M University College of Medicine, 2121 W Holcombe Blvd., Houston, TX, 77030, USA.
authors.forename: Wan-Mohaiza
authors.initials: WM
authors.lastname: Dashwood
authors.affiliation: College of Veterinary Medicine, Oregon State University, Corvallis, OR, USA.
authors.forename: Christiane V
authors.initials: CV
authors.lastname: Löhr
authors.affiliation: Linus Pauling Institute, Oregon State University, Corvallis, OR, USA.|Department of Environmental and Molecular Toxicology, Oregon State University, Corvallis, OR, USA.
authors.forename: David E
authors.initials: DE
authors.lastname: Williams
authors.affiliation: Linus Pauling Institute, Oregon State University, Corvallis, OR, USA.|College of Public Health and Human Sciences, Oregon State University, Corvallis, OR, USA.
authors.forename: Emily
authors.initials: E
authors.lastname: Ho
authors.affiliation: Department of Clinical Cancer Prevention, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Susanne
authors.initials: S
authors.lastname: Mertens-Talcott
authors.affiliation: Center for Epigenetics and Disease Prevention, Texas A&M University College of Medicine, 2121 W Holcombe Blvd., Houston, TX, 77030, USA. rdashwood@ibt.tamhsc.edu.|Department of Clinical Cancer Prevention, The University of Texas MD Anderson Cancer Center, Houston, TX, USA. rdashwood@ibt.tamhsc.edu.|Department of Molecular and Cellular Medicine, Texas A&M College of Medicine, College Station, TX, USA. rdashwood@ibt.tamhsc.edu.|Department of Nutrition and Food Science, Texas A&M University, College Station, TX, USA. rdashwood@ibt.tamhsc.edu.
authors.forename: Roderick H
authors.initials: RH
authors.lastname: Dashwood
mesh_terms: D000588:Amines / Q000737:chemistry / Q000633:toxicity*; D000818:Animals; D015197:Carcinogenicity Tests / Q000379:methods*; D005786:Gene Expression Regulation / Q000187:drug effects*; D006801:Humans; D007093:Imidazoles / Q000633:toxicity; D000090062:Kruppel-Like Factor 4; D008297:Male; D035683:MicroRNAs / Q000032:analysis*; D009369:Neoplasms / Q000235:genetics*; D011916:Rats, Inbred F344
chemical_list: D000588:Amines; D007093:Imidazoles; C000715467:KLF4 protein, human; C000715469:Klf4 protein, rat; D000090062:Kruppel-Like Factor 4; C548145:MIRNLET7 microRNA, rat; D035683:MicroRNAs; C049584:2-amino-1-methyl-6-phenylimidazo(4,5-b)pyridine
keywords: Colorectal cancer; MYC; MicroRNA; Pan-cancer; PhIP; TCGA