Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0079731 (B-cell lymphoma)
 16,671 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

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.
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PMID:Accumulation of miR-155 and BIC RNA in human B cell lymphomas. 1573 15

In a previous study we demonstrated high expression of the non-coding BIC gene in the vast majority of Hodgkin's lymphomas (HLs). Evidence suggesting that BIC is a primary microRNA transcript containing the mature microRNA-155 (miR-155) as part of a RNA hairpin is now accumulating. We therefore analysed HL cell lines and tissue samples to determine whether miR-155 is also expressed in HL. High levels of miR-155 could be demonstrated, indicating that BIC is processed into a microRNA in HL. Most non-HL subtypes were negative for BIC as determined by RNA-ISH. However, in diffuse large B cell lymphoma (DLBCL) and primary mediastinal B cell lymphoma (PMBL), significant percentages of positive tumour cells were observed in 12/18 and 8/8 cases. A higher proportion of tumour cells were positive for BIC in DLBCL with activated B cell-like phenotype than in DLBCL with germinal centre B cell-like phenotype. Differential BIC expression was confirmed by qRT-PCR analysis. Northern blot analysis showed expression of miR-155 in all DLBCL and PMBL derived cell lines and tissue samples analysed. In summary, we demonstrate expression of primary microRNA BIC and its derivative miR-155 in HL, PMBL and DLBCL.
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PMID:BIC and miR-155 are highly expressed in Hodgkin, primary mediastinal and diffuse large B cell lymphomas. 1604 95

Fast and reliable differential diagnosis of Burkitt lymphoma (BL) vs. diffuse large B cell lymphoma (DLBCL) is of major importance for therapeutic decisions and patient outcome. Aggressive B cell non-Hodgkin lymphomas (B-NHLs) that do not belong to the abovementioned entities were categorized by the current WHO lymphoma classification as "B-cell lymphoma, unclassifiable, with features intermediate between DLBCL and BL" (DLBCL/BL). We have recently described a DLBCL/BL subgroup with recurrent chromosome 11q aberrations, resembling BL (B-NHLs[11q]). Here, we analyzed 102 prospectively collected fine needle aspirates from patients with aggressive B-NHLs in order to investigate the potential of microRNA (miR)-155, its precursor BIC, as well as miR-21 and miR-26a to differentiate BL from DLBCL, and from DLBCL/BL that include B-NHLs[11q]. Both BL and DLBCL/BL cases, including B-NHLs[11q], demonstrated significantly lower expression levels of miR-155/BIC, miR-21, and miR-26a compared to primary DLBCL. In conclusion, the miRs expression in B-NHLs[11q] provides a new suggestion, in addition to pathomorphological and clinical similarities between classical, i.e., MYC translocation-positive BL, and B-NHLs[11q], to recognize the B-NHLs[11q] subgroup of DLBCL/BL category as a MYC translocation-negative variant of BL in most cases, and points to the potential utility of miR-155/BIC/miR-21/miR-26a for the differential diagnosis of a heterogeneous category of DLBCL/BL.
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PMID:miR expression in MYC-negative DLBCL/BL with partial trisomy 11 is similar to classical Burkitt lymphoma and different from diffuse large B-cell lymphoma. 2567 2