title: Chemoprevention of cigarette smoke-induced alterations of MicroRNA expression in rat lungs.
abstract: We previously showed that exposure to environmental cigarette smoke (ECS) for 28 days causes extensive downregulation of microRNA expression in the lungs of rats, resulting in the overexpression of multiple genes and proteins. In the present study, we evaluated by microarray the expression of 484 microRNAs in the lungs of either ECS-free or ECS-exposed rats treated with the orally administered chemopreventive agents N-acetylcysteine, oltipraz, indole-3-carbinol, 5,6-benzoflavone, and phenethyl isothiocyanate (as single agents or in combinations). This is the first study of microRNA modulation by chemopreventive agents in nonmalignant tissues. Scatterplot, hierarchical cluster, and principal component analyses of microarray and quantitative PCR data showed that none of the above chemopreventive regimens appreciably affected the baseline microRNA expression, indicating potential safety. On the other hand, all of them attenuated ECS-induced alterations but to a variable extent and with different patterns, indicating potential preventive efficacy. The main ECS-altered functions that were modulated by chemopreventive agents included cell proliferation, apoptosis, differentiation, Ras activation, P53 functions, NF-kappaB pathway, transforming growth factor-related stress response, and angiogenesis. Some microRNAs known to be polymorphic in humans were downregulated by ECS and were protected by chemopreventive agents. This study provides proof-of-concept and validation of technology that we are further refining to screen and prioritize potential agents for continued development and to help elucidate their biological effects and mechanisms. Therefore, microRNA analysis may provide a new tool for predicting at early carcinogenesis stages both the potential safety and efficacy of cancer chemopreventive agents.
authors.affiliation: Department of Health Sciences, University of Genoa, Italy.
authors.forename: Alberto
authors.initials: A
authors.lastname: Izzotti
authors.forename: George A
authors.initials: GA
authors.lastname: Calin
authors.forename: Vernon E
authors.initials: VE
authors.lastname: Steele
authors.forename: Cristina
authors.initials: C
authors.lastname: Cartiglia
authors.forename: Mariagrazia
authors.initials: M
authors.lastname: Longobardi
authors.forename: Carlo M
authors.initials: CM
authors.lastname: Croce
authors.forename: Silvio
authors.initials: S
authors.lastname: De Flora
mesh_terms: D000111:Acetylcysteine / Q000494:pharmacology; D000818:Animals; D016588:Anticarcinogenic Agents / Q000494:pharmacology*; D018890:Chemoprevention / Q000379:methods; D016000:Cluster Analysis; D004791:Enzyme Inhibitors / Q000494:pharmacology; D015870:Gene Expression / Q000187:drug effects*; D007211:Indoles / Q000494:pharmacology; D017879:Isothiocyanates / Q000494:pharmacology; D008168:Lung / Q000187:drug effects*; D008297:Male; D035683:MicroRNAs / Q000032:analysis / Q000096:biosynthesis* / Q000187:drug effects*; D020411:Oligonucleotide Array Sequence Analysis; D025341:Principal Component Analysis; D011719:Pyrazines / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013871:Thiones; D013876:Thiophenes; D014028:Tobacco Smoke Pollution / Q000009:adverse effects*; D019324:beta-Naphthoflavone / Q000494:pharmacology
chemical_list: D016588:Anticarcinogenic Agents; D004791:Enzyme Inhibitors; D007211:Indoles; D017879:Isothiocyanates; D035683:MicroRNAs; D011719:Pyrazines; D013871:Thiones; D013876:Thiophenes; D014028:Tobacco Smoke Pollution; D019324:beta-Naphthoflavone; C026209:oltipraz; C058305:phenethyl isothiocyanate; C016517:indole-3-carbinol; D000111:Acetylcysteine