Accumulation of miR-155 and BIC RNA in human B cell lymphomas Academic Article uri icon


MeSH Major

  • Lymphoma, B-Cell
  • Lymphoma, Large B-Cell, Diffuse
  • MicroRNAs
  • RNA, Untranslated


  • We show that the microRNA miR-155 can be processed from sequences present in BIC RNA, a spliced and polyadenylated but non-protein-coding RNA that accumulates in lymphoma cells. The precursor of miR-155 is likely a transient spliced or unspliced nuclear BIC transcript rather than accumulated BIC RNA, which is primarily cytoplasmic. By using a sensitive and quantitative assay, we find that clinical isolates of several types of B cell lymphomas, including diffuse large B cell lymphoma (DLBCL), have 10- to 30-fold higher copy numbers of miR-155 than do normal circulating B cells. Similarly, the quantities of BIC RNA are elevated in lymphoma cells, but ratios of the amounts of the two RNAs are not constant, suggesting that the level of miR-155 is controlled by transcription and processing. Significantly higher levels of miR-155 are present in DLBCLs with an activated B cell phenotype than with the germinal center phenotype. Because patients with activated B cell-type DLBCL have a poorer clinical prognosis, quantification of this microRNA may be diagnostically useful.

publication date

  • March 8, 2005



  • Academic Article



  • eng

PubMed Central ID

  • PMC552785

Digital Object Identifier (DOI)

  • 10.1073/pnas.0500613102

PubMed ID

  • 15738415

Additional Document Info

start page

  • 3627

end page

  • 32


  • 102


  • 10