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217CLL

ABSTRACT: In this study we compared the miRNA expression profile of 217 CLL cases versus various normal B cell subpopulations in the attempt of finding the normal cell subset most similar to CLL cells and gain information on possible miRNA deregulations. Our analyses indicated that CLL cells exhibited a miRNA expression pattern close to memory and marginal zone-like B cells. Conversely, tonsil GC and CD19+ peripheral blood B cells appeared only distantly related to CLL. Memory and marginal zone B cells were used as reference to identify differentially expressed miRNAs in CLL, which included miR-193b, miR-33b*, miR-365, miR-181b and miR-196a/b among the down-regulated and miR-23a/b, miR-26a, miR-130a, miR-532 (5p and 3p) among the up-regulated miRNAs. We also investigated differences of miRNA expression related to the IGHV somatic mutation status and to deletions at 13q, 11q and 17p or trisomy 12. Little differences were detected between unmutated (UM) versus mutated (M) CLLs, although miR-29c, miR-29c* and miR-146b were strongly down-modulated in the UM-CLL subgroup. Each of the cytogenetic classes of CLL was characterized by uniquely abnormally expressed miRNAs. Deletion at 13q displayed a reduced expression of miR-16, more evident if the deletion was biallelic. Deletion of 17p was characterized by the strong reduction of miR-34a expression and up-regulation of miR-96. Deletion at 11q was characterized by the up-regulation of miR-338-3p and miR-769-5p. Trisomy 12 was characterized by a strong down-regulation of miR-483-5p.

ORGANISM(S): Homo sapiens

SUBMITTER: Manuela Ferracin

PROVIDER: E-MTAB-1454 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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