Quantitative technologies establish a novel microRNA profile of chronic lymphocytic leukemia.

MicroRNAs (miRNAs) are a novel class of small noncoding RNAs that modulate the expression of genes at the posttranscriptional level. These small molecules have been shown to be involved in cancer, apoptosis, and cell metabolism. In the present study we provide an informative profile of the expression of miRNAs in primary chronic lymphocytic leukemia (CLL) cells using 2 independent and quantitative methods: miRNA cloning and quantitative real-time-polymerase chain reaction (qRT-PCR) of mature miRNAs. Both approaches show that miR-21 and miR-155 are dramatically overexpressed in patients with CLL, although the corresponding genomic loci are not amplified. miR-150 and miR-92 are also significantly deregulated in patients with CLL. In addition, we detected a marked miR-15a and miR-16 decrease in about 11% of cases. Finally, we identified a set of miRNAs whose expression correlates with biologic parameters of prognostic relevance, particularly with the mutational status of the IgV(H) genes. In summary, the results of this study offer for the first time a comprehensive and quantitative profile of miRNA expression in CLL and their healthy counterpart, suggesting that miRNAs could play a primary role in the disease itself.

[1]  C. Burge,et al.  Conserved Seed Pairing, Often Flanked by Adenosines, Indicates that Thousands of Human Genes are MicroRNA Targets , 2005, Cell.

[2]  S. Ōmura,et al.  Deregulation of the ubiquitin system and p53 proteolysis modify the apoptotic response in B-CLL lymphocytes. , 2000, Blood.

[3]  K. Rajewsky,et al.  Tracing B cell development in human germinal centres by molecular analysis of single cells picked from histological sections. , 1993, The EMBO journal.

[4]  Emili Montserrat,et al.  ZAP-70 expression as a surrogate for immunoglobulin-variable-region mutations in chronic lymphocytic leukemia. , 2003, The New England journal of medicine.

[5]  Mariette Schrier,et al.  A Genetic Screen Implicates miRNA-372 and miRNA-373 As Oncogenes in Testicular Germ Cell Tumors , 2006, Cell.

[6]  Hervé Seitz,et al.  Rethinking the Microprocessor , 2006, Cell.

[7]  C. Croce,et al.  MicroRNA deregulation in human thyroid papillary carcinomas. , 2006, Endocrine-related cancer.

[8]  Arndt Borkhardt,et al.  High expression of precursor microRNA‐155/BIC RNA in children with Burkitt lymphoma , 2004, Genes, chromosomes & cancer.

[9]  Yi Zhao,et al.  NONCODE: an integrated knowledge database of non-coding RNAs , 2004, Nucleic Acids Res..

[10]  G. Hannon,et al.  Control of translation and mRNA degradation by miRNAs and siRNAs. , 2006, Genes & development.

[11]  N. Rajewsky,et al.  Cell-type-specific signatures of microRNAs on target mRNA expression. , 2006, Proceedings of the National Academy of Sciences of the United States of America.

[12]  K. Gunsalus,et al.  Combinatorial microRNA target predictions , 2005, Nature Genetics.

[13]  Z. Mourelatos,et al.  A human, ATP-independent, RISC assembly machine fueled by pre-miRNA. , 2005, Genes & development.

[14]  Jian Gu,et al.  Small RNA database , 1996, Nucleic Acids Res..

[15]  R. Stephens,et al.  Unique microRNA molecular profiles in lung cancer diagnosis and prognosis. , 2006, Cancer cell.

[16]  F. Mancini,et al.  Chronic lymphocytic leukemia patients with highly stable and indolent disease show distinctive phenotypic and genotypic features. , 2003, Blood.

[17]  C. Croce,et al.  MicroRNA profiling reveals distinct signatures in B cell chronic lymphocytic leukemias. , 2004, Proceedings of the National Academy of Sciences of the United States of America.

[18]  K. Rajewsky,et al.  Detection of clonal B cell populations in paraffin-embedded tissues by polymerase chain reaction. , 1993, The American journal of pathology.

[19]  Vladimir Benes,et al.  A sensitive array for microRNA expression profiling (miChip) based on locked nucleic acids (LNA). , 2006, RNA.

[20]  K. Kosik,et al.  MicroRNA-21 is an antiapoptotic factor in human glioblastoma cells. , 2005, Cancer research.

[21]  Brian S. Roberts,et al.  Simple, quantitative primer-extension PCR assay for direct monitoring of microRNAs and short-interfering RNAs. , 2005, RNA.

[22]  Phillip A Sharp,et al.  siRNAs can function as miRNAs , 2003 .

[23]  C. Sander,et al.  Identification of microRNAs of the herpesvirus family , 2005, Nature Methods.

[24]  Marc K Hellerstein,et al.  In vivo measurements document the dynamic cellular kinetics of chronic lymphocytic leukemia B cells. , 2005, The Journal of clinical investigation.

[25]  R. Foà,et al.  New developments in the diagnosis, prognosis and treatment of chronic lymphocytic leukemia , 2005, Current opinion in oncology.

[26]  A Benner,et al.  Genomic aberrations and survival in chronic lymphocytic leukemia. , 2000, The New England journal of medicine.

[27]  S. Lowe,et al.  A microRNA polycistron as a potential human oncogene , 2005, Nature.

[28]  L. Rassenti,et al.  Chronic lymphocytic leukemia B cells express restricted sets of mutated and unmutated antigen receptors. , 1998, The Journal of clinical investigation.

[29]  C. Croce,et al.  Frequent deletions and down-regulation of micro- RNA genes miR15 and miR16 at 13q14 in chronic lymphocytic leukemia , 2002, Proceedings of the National Academy of Sciences of the United States of America.

[30]  Muller Fabbri,et al.  A MicroRNA signature associated with prognosis and progression in chronic lymphocytic leukemia. , 2005, The New England journal of medicine.

[31]  David Botstein,et al.  Relation of Gene Expression Phenotype to Immunoglobulin Mutation Genotype in B Cell Chronic Lymphocytic Leukemia , 2001, The Journal of experimental medicine.

[32]  Arthur Weiss,et al.  ZAP-70 compared with immunoglobulin heavy-chain gene mutation status as a predictor of disease progression in chronic lymphocytic leukemia. , 2004, The New England journal of medicine.

[33]  W. Tam,et al.  miR‐155/BIC as an oncogenic microRNA , 2006, Genes, chromosomes & cancer.

[34]  C. Benz,et al.  Optimized high-throughput microRNA expression profiling provides novel biomarker assessment of clinical prostate and breast cancer biopsies , 2006, Molecular Cancer.

[35]  C. Croce,et al.  miR-15 and miR-16 induce apoptosis by targeting BCL2. , 2005, Proceedings of the National Academy of Sciences of the United States of America.

[36]  N. Rajewsky microRNA target predictions in animals , 2006, Nature Genetics.

[37]  F. Slack,et al.  RAS Is Regulated by the let-7 MicroRNA Family , 2005, Cell.

[38]  M. Byrom,et al.  Antisense inhibition of human miRNAs and indications for an involvement of miRNA in cell growth and apoptosis , 2005, Nucleic acids research.

[39]  D. Bartel,et al.  MicroRNAs Modulate Hematopoietic Lineage Differentiation , 2004, Science.

[40]  Adrian Wiestner,et al.  ZAP-70 expression identifies a chronic lymphocytic leukemia subtype with unmutated immunoglobulin genes, inferior clinical outcome, and distinct gene expression profile. , 2003, Blood.

[41]  C. Peschel,et al.  Constitutively activated phosphatidylinositol-3 kinase (PI-3K) is involved in the defect of apoptosis in B-CLL: association with protein kinase Cdelta. , 2002, Blood.

[42]  M. Hallek,et al.  Molecular pathogenesis of chronic lymphocytic leukemia: factors and signaling pathways regulating cell growth and survival , 1999, Journal of Molecular Medicine.

[43]  Wayne Tam,et al.  Accumulation of miR-155 and BIC RNA in human B cell lymphomas. , 2005, Proceedings of the National Academy of Sciences of the United States of America.