Signatures of microRNAs and selected microRNA target genes in human melanoma.

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.

Philippidou D ，Schmitt M ，Moser D ，Margue C ，Nazarov PV ，Muller A ，Vallar L ，Nashan D ，Behrmann I ，Kreis S ... -  《-》

Characterization of B- and T-lineage acute lymphoblastic leukemia by integrated analysis of MicroRNA and mRNA expression profiles.

Acute lymphoblastic leukemia (ALL) is an heterogeneous disease comprising several subentities that differ for both immunophenotypic and molecular characteristics. Over the years, the biological understanding of this neoplasm has largely increased. Gene expression profiling has allowed to identify specific signatures for the different ALL subsets and permitted the identification of pathways deregulated by a given lesion. MicroRNAs (miRNAs) are small noncoding RNAs, which play a pivotal role in several cellular functions. In this study, we investigated miRNAs expression profiles in a series of adult ALL cases by microarray analysis. Unsupervised hierarchical clustering largely recapitulated ALL subgroups. Furthermore, we identified miR-148, miR-151, and miR-424 as discriminative of T-lineage versus B-lineage ALL; ANOVA highlighted a set of six miRNAs-namely miR-425-5p, miR-191, miR-146b, miR-128, miR-629, and miR-126-that can discriminate B-lineage ALL subgroups harboring specific molecular lesions. These results were confirmed and extended by quantitative-PCR on a further cohort of cases. Finally, we used Pearson correlation analysis to combine miRNA and gene expression profiles. The distribution of correlation coefficients generated by comparing the expression of every miRNA/gene pair in our data set shows enrichment of both positively and negatively correlated pairs over background distributions obtained using randomized data. Moreover, a clear enrichment for predicted miRNA:target pairs is observed at negative correlation coefficient intervals. Signal-to-noise ratio highlighted several miRNA/gene pairs with a possible role in the disease. In fact, gene set enrichment analysis of genes composing the selected miRNA/gene pairs displays over-representation of functional categories related to cancer and cell-cycle regulation.

Fulci V ，Colombo T ，Chiaretti S ，Messina M ，Citarella F ，Tavolaro S ，Guarini A ，Foà R ，Macino G ... -  《-》

Comparative microarray analysis of microRNA expression profiles in primary cutaneous malignant melanoma, cutaneous malignant melanoma metastases, and benign melanocytic nevi.

Sand M ，Skrygan M ，Sand D ，Georgas D ，Gambichler T ，Hahn SA ，Altmeyer P ，Bechara FG ... -  《-》

Integrative high-resolution microarray analysis of human myeloma cell lines reveals deregulated miRNA expression associated with allelic imbalances and gene expression profiles.

Lionetti M ，Agnelli L ，Mosca L ，Fabris S ，Andronache A ，Todoerti K ，Ronchetti D ，Deliliers GL ，Neri A ... -  《-》

Altered expression of selected microRNAs in melanoma: antiproliferative and proapoptotic activity of miRNA-155.

Levati L ，Alvino E ，Pagani E ，Arcelli D ，Caporaso P ，Bondanza S ，Di Leva G ，Ferracin M ，Volinia S ，Bonmassar E ，Croce CM ，D'Atri S ... -  《INTERNATIONAL JOURNAL OF ONCOLOGY》