title: Colorectal adenoma and carcinoma specific miRNA profiles in biopsy and their expression in plasma specimens.
abstract: MiRNA expression markers are well characterized in colorectal cancer (CRC), but less is known about miRNA expression profiles in colorectal adenomas. Genome-wide miRNA and mRNA expression analyses were conducted through the colorectal adenoma dysplasia sequence. Furthermore, analysis of the expression levels of miRNAs in matched plasma samples was performed, focusing on biomarker candidates; miRNA and mRNA expression analyses were performed on colorectal biopsies and plasma samples (20 normals; 11 tubular and 9 tubulovillous adenomas; 20 colorectal carcinomas) by miRNA 3.0 and Human Transcriptome Array (Affymetrix) and validated by RT-qPCR. Microarray data were analyzed using Expression Console and mRNA targets were predicted using miRWALK 2.0.
  
  
  
  Based on microarray analysis, 447 miRNAs were expressed in tissue and 320 in plasma. Twelve were upregulated (miR-31, 8-foldp< 0.001) and 11 were downregulated (miR-10b 3-foldp< 0.001) in neoplastic lesions compared to normal group. Eleven miRNAs showed altered expression between adenoma subtypes (miR-183 2.8-fold change,p< 0.007). Expression level of 24 miRNAs differed between adenoma and CRC groups (including miR-196a, 3.5-fold). Three miRNAs (miR-31, miR-4506, miR-452*) were differentially expressed in adenoma compared to normal both in tissue and plasma samples. miRNA expression data were confirmed by RT-PCR both in plasma and matched tissue samples.
  
  
  
  MiRNAs showed characteristic expression changes during CRC development in tissue. miRNAs were also presented in plasma and positively correlated with matched tissue expression levels. The identified miRNA expression changes could be verified RT-PCR methods facilitating routine application.
authors.affiliation: Molecular Gastroenterology Laboratory, 2nd Department of Internal Medicine, Semmelweis University, Szentkirályi Str. 46, Budapest, 1088 Hungary.
authors.forename: Zsófia Brigitta
authors.initials: ZB
authors.lastname: Nagy
authors.affiliation: Molecular Medicine Research Group, Hungarian Academy of Sciences, Budapest, Hungary.
authors.forename: Barnabás
authors.initials: B
authors.lastname: Wichmann
authors.affiliation: Molecular Gastroenterology Laboratory, 2nd Department of Internal Medicine, Semmelweis University, Szentkirályi Str. 46, Budapest, 1088 Hungary.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Kalmár
authors.affiliation: Molecular Medicine Research Group, Hungarian Academy of Sciences, Budapest, Hungary.
authors.forename: Orsolya
authors.initials: O
authors.lastname: Galamb
authors.affiliation: Molecular Gastroenterology Laboratory, 2nd Department of Internal Medicine, Semmelweis University, Szentkirályi Str. 46, Budapest, 1088 Hungary.
authors.forename: Barbara Kinga
authors.initials: BK
authors.lastname: Barták
authors.affiliation: Current Address: Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA USA.
authors.forename: Sándor
authors.initials: S
authors.lastname: Spisák
authors.affiliation: Molecular Medicine Research Group, Hungarian Academy of Sciences, Budapest, Hungary.
authors.forename: Zsolt
authors.initials: Z
authors.lastname: Tulassay
authors.affiliation: Molecular Medicine Research Group, Hungarian Academy of Sciences, Budapest, Hungary.
authors.forename: Béla
authors.initials: B
authors.lastname: Molnár
mesh_terms: D000236:Adenoma / Q000097:blood / Q000235:genetics*; D015179:Colorectal Neoplasms / Q000097:blood / Q000235:genetics*; D003198:Computer Simulation; D020869:Gene Expression Profiling / Q000379:methods*; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D035683:MicroRNAs / Q000235:genetics*; D020411:Oligonucleotide Array Sequence Analysis; D060888:Real-Time Polymerase Chain Reaction
chemical_list: D035683:MicroRNAs
keywords: Colorectal adenoma; Colorectal cancer; Microarray; Real-time PCR; miRNA profiling; microRNA