title: Signatures of microRNAs and selected microRNA target genes in human melanoma.
abstract: Small noncoding microRNAs (miRNA) regulate the expression of target mRNAs by repressing their translation or orchestrating their sequence-specific degradation. In this study, we investigated miRNA and miRNA target gene expression patterns in melanoma to identify candidate biomarkers for early and progressive disease. Because data presently available on miRNA expression in melanoma are inconsistent thus far, we applied several different miRNA detection and profiling techniques on a panel of 10 cell lines and 20 patient samples representing nevi and primary or metastatic melanoma. Expression of selected miRNAs was inconsistent when comparing cell line-derived and patient-derived data. Moreover, as expected, some discrepancies were also detected when miRNA microarray data were correlated with qPCR-measured expression levels. Nevertheless, we identified miRNA-200c to be consistently downregulated in melanocytes, melanoma cell lines, and patient samples, whereas miRNA-205 and miRNA-23b were markedly reduced only in patient samples. In contrast, miR-146a and miR-155 were upregulated in all analyzed patients but none of the cell lines. Whole-genome microarrays were performed for analysis of selected melanoma cell lines to identify potential transcriptionally regulated miRNA target genes. Using Ingenuity pathway analysis, we identified a deregulated gene network centered around microphthalmia-associated transcription factor, a transcription factor known to play a key role in melanoma development. Our findings define miRNAs and miRNA target genes that offer candidate biomarkers in human melanoma.
authors.affiliation: Life Sciences Research Unit, University of Luxembourg, Freiburg, Germany.
authors.forename: Demetra
authors.initials: D
authors.lastname: Philippidou
authors.forename: Martina
authors.initials: M
authors.lastname: Schmitt
authors.forename: Dirk
authors.initials: D
authors.lastname: Moser
authors.forename: Christiane
authors.initials: C
authors.lastname: Margue
authors.forename: Petr V
authors.initials: PV
authors.lastname: Nazarov
authors.forename: Arnaud
authors.initials: A
authors.lastname: Muller
authors.forename: Laurent
authors.initials: L
authors.lastname: Vallar
authors.forename: Dorothee
authors.initials: D
authors.lastname: Nashan
authors.forename: Iris
authors.initials: I
authors.lastname: Behrmann
authors.forename: Stephanie
authors.initials: S
authors.lastname: Kreis
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000235:genetics* / Q000378:metabolism; D002460:Cell Line; D005260:Female; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic; D056726:Genetic Association Studies; D006801:Humans; D008297:Male; D008544:Melanocytes / Q000378:metabolism; D008545:Melanoma / Q000235:genetics* / Q000473:pathology; D035683:MicroRNAs / Q000502:physiology*; D051739:Microphthalmia-Associated Transcription Factor / Q000235:genetics / Q000378:metabolism; D008875:Middle Aged; D009508:Nevus, Pigmented / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012878:Skin Neoplasms / Q000235:genetics* / Q000473:pathology
chemical_list: D014408:Biomarkers, Tumor; D035683:MicroRNAs; D051739:Microphthalmia-Associated Transcription Factor; D012333:RNA, Messenger