title: MicroRNA expression analysis in high fat diet-induced NAFLD-NASH-HCC progression: study on C57BL/6J mice.
abstract: BACKGROUND
  Hepatocellular carcinoma (HCC) is the most common malignant tumor of the liver. Non-alcoholic fatty liver disease (NAFLD) is a frequent chronic liver disorder in developed countries. NAFLD can progress through the more severe non alcoholic steatohepatitis (NASH), cirrhosis and, lastly, HCC. Genetic and epigenetic alterations of coding genes as well as deregulation of microRNAs (miRNAs) activity play a role in HCC development. In this study, the C57BL/6J mouse model was long term high-fat (HF) or low-fat (LF) diet fed, in order to analyze molecular mechanisms responsible for the hepatic damage progression.
  
  
  METHODS
  Mice were HF or LF diet fed for different time points, then plasma and hepatic tissues were collected. Histological and clinical chemistry assays were performed to assess the progression of liver disease. MicroRNAs' differential expression was evaluated on pooled RNAs from tissues, and some miRNAs showing dysregulation were further analyzed at the individual level.
  
  
  RESULTS
  Cholesterol, low and high density lipoproteins, triglycerides and alanine aminotransferase increase was detected in HF mice. Gross anatomical examination revealed hepatomegaly in HF livers, and histological analysis highlighted different degrees and levels of steatosis, inflammatory infiltrate and fibrosis in HF and LF animals, demonstrating the progression from NAFLD through NASH. Macroscopic nodules, showing typical neoplastic features, were observed in 20% of HF diet fed mice. Fifteen miRNAs differentially expressed in HF with respect to LF hepatic tissues during the progression of liver damage, and in tumors with respect to HF non tumor liver specimens were identified. Among them, miR-340-5p, miR-484, miR-574-3p, miR-720, whose expression was never described in NAFLD, NASH and HCC tissues, and miR-125a-5p and miR-182, which showed early and significant dysregulation in the sequential hepatic damage process.
  
  
  CONCLUSIONS
  In this study, fifteen microRNAs which were modulated in hepatic tissues and in tumors during the transition NAFLD-NASH-HCC are reported. Besides some already described, new and early dysregulated miRNAs were identified. Functional analyses are needed to validate the results here obtained, and to better define the role of these molecules in the progression of the hepatic disease.
authors.affiliation: Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, via Vetoio - Coppito 2, 67100, L'Aquila, Italy. alessandra.tessitore@univaq.it.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Tessitore
authors.affiliation: Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, via Vetoio - Coppito 2, 67100, L'Aquila, Italy. ge.c@live.it.
authors.forename: Germana
authors.initials: G
authors.lastname: Cicciarelli
authors.affiliation: Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, via Vetoio - Coppito 2, 67100, L'Aquila, Italy. filippo.delvecchio1@graduate.univaq.it.
authors.forename: Filippo
authors.initials: F
authors.lastname: Del Vecchio
authors.affiliation: Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, via Vetoio - Coppito 2, 67100, L'Aquila, Italy. agata.gaggiano@gmail.com.
authors.forename: Agata
authors.initials: A
authors.lastname: Gaggiano
authors.affiliation: Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, via Vetoio - Coppito 2, 67100, L'Aquila, Italy. danielaverzella@tiscali.it.
authors.forename: Daniela
authors.initials: D
authors.lastname: Verzella
authors.affiliation: Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, via Vetoio - Coppito 2, 67100, L'Aquila, Italy. f.fausta@hotmail.it.
authors.forename: Mariafausta
authors.initials: M
authors.lastname: Fischietti
authors.affiliation: Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, via Vetoio - Coppito 2, 67100, L'Aquila, Italy. valentina.mastroiaco@graduate.univaq.it.
authors.forename: Valentina
authors.initials: V
authors.lastname: Mastroiaco
authors.affiliation: Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, via Vetoio - Coppito 2, 67100, L'Aquila, Italy. antonella.vetuschi@univaq.it.
authors.forename: Antonella
authors.initials: A
authors.lastname: Vetuschi
authors.affiliation: Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, via Vetoio - Coppito 2, 67100, L'Aquila, Italy. roberta.sferra@univaq.it.
authors.forename: Roberta
authors.initials: R
authors.lastname: Sferra
authors.affiliation: S. Salvatore Hospital, Unit of Laboratory Medicine, L'Aquila, Italy. barnabeiremo@vodafone.it.
authors.forename: Remo
authors.initials: R
authors.lastname: Barnabei
authors.affiliation: Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, via Vetoio - Coppito 2, 67100, L'Aquila, Italy. dariacapece@gmail.com.
authors.forename: Daria
authors.initials: D
authors.lastname: Capece
authors.affiliation: Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, via Vetoio - Coppito 2, 67100, L'Aquila, Italy. francesca.zazzeroni@univaq.it.
authors.forename: Francesca
authors.initials: F
authors.lastname: Zazzeroni
authors.affiliation: Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, via Vetoio - Coppito 2, 67100, L'Aquila, Italy. edoardo.alesse@univaq.it.
authors.forename: Edoardo
authors.initials: E
authors.lastname: Alesse
mesh_terms: D000818:Animals; D006528:Carcinoma, Hepatocellular / Q000235:genetics* / Q000473:pathology; D045744:Cell Line, Tumor; D002784:Cholesterol / Q000097:blood; D059305:Diet, High-Fat; D004195:Disease Models, Animal; D018450:Disease Progression; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008113:Liver Neoplasms / Q000235:genetics* / Q000473:pathology; D051379:Mice; D035683:MicroRNAs / Q000096:biosynthesis* / Q000235:genetics; D065626:Non-alcoholic Fatty Liver Disease / Q000235:genetics* / Q000473:pathology; D014280:Triglycerides / Q000097:blood
chemical_list: D035683:MicroRNAs; D014280:Triglycerides; D002784:Cholesterol