Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.24.11 (CD10)
 9,792 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Epstein-Barr virus (EBV) immortalized cells and Burkitt lymphoma cells have a completely different growth pattern and phenotype. EBV immortalized cells express a set of 11 viral genes to accommodate B cell activation and proliferation, whereas EBV-positive Burkitt lymphoma cells highly express the c-myc oncogene that is activated through translocation into 1 of the immunoglobulin loci and EBNA1 as the only viral protein. We have developed a primary human B cell line conditionally immortalized by Epstein-Barr virus in which the viral gene program responsible for the induction of proliferation can be switched on and off by the addition or withdrawal of estrogen (cell line EREB2-5). Starting from this cell line we have generated 2 daughter cell lines that proliferate in a c-myc dependent fashion, 1 with a highly active exogenous c-myc gene (cell line A1) and 1 with a regulatable c-myc gene that can be switched on by withdrawal and switched off by addition of tetracycline (cell line P493-6). The comparison of the 3 cell lines has allowed us to dissect the contribution of c-myc and EBV genes to the regulation of the growth pattern and expression of cell surface molecules. We show that MYC and EBNA2 (and their respective target genes) have opposing effects on the expression of several surface markers involved in B cell activation. We show that MYC contributes to the phenotype of Burkitt lymphoma cells by upregulating CD10 and CD38 and downregulating activation markers. The phenotype of the cells is determined on one hand by the absence of the viral gene products EBNA2 and LMP1 that mediate the phenotype of activated lymphoblasts and to a lesser extent by an active contribution of the c-myc gene.
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PMID:Antagonistic effects of c-myc and Epstein-Barr virus latent genes on the phenotype of human B cells. 1151 42

A chromosomal translocation involving the MYC gene is characteristic of Burkitt lymphoma (BL) and represents a molecular disease marker with diagnostic and clinical implications. The detection of MYC breakpoints is hampered by technical problems, including the distribution of the breakpoints over a very large genomic region of approximately 1,000 kb. In this article, we report on the testing and validation of a segregation fluorescence in situ hybridization (FISH) assay for MYC breakpoints on a large series of BLs. A contig of overlapping genomic clones was generated, and two probe sets flanking the MYC gene were selected. Both probe sets were tested in an interphase FISH segregation assay on 8 B-cell lymphoma cell lines and 32 lymphoma samples with proved 8q24/MYC abnormalities and validated in 47 BLs from The Netherlands, Brazil, and Uganda. MYC translocation breakpoints were identified in 98% of the tumors of the test series and in 89% of the cases of the validation series. In 89% of all positive samples, the breakpoints were located between 190 kb 5' and 50 kb 3' of MYC. Nine cases had more distant breakpoints, and in one patient an insertion of MYC into the IGH region was detected. In two of the three BLs lacking CD10 expression, no breakpoint could be detected, suggesting that CD10 is a discriminative marker of BL. We did not find consistent differences between BL and atypical BL in incidence of an MYC breakpoint.
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PMID:Interphase fluorescence in situ hybridization for detection of 8q24/MYC breakpoints on routine histologic sections: validation in Burkitt lymphomas from three geographic regions. 1503 63

Mature B-cell acute lymphoblastic leukemia (ALL) is typically associated with the FAB-L3 morphology and rearrangement of the MYC gene, features characteristic of the leukemic phase of Burkitt's lymphoma. However, the term 'mature' has also been used to describe other rare cases of B-ALL with light-chain surface immunoglobulin expression. In contrast, infantile B-cell ALL is generally characterized by rearrangement of the MLL gene, an immature pro-B-cell phenotype, and CD10 negativity. We describe two unusual cases of infantile B-ALL with non-L3 morphology, expressing a mature B-cell phenotype (lambda sIg+, CD19+, CD10-, TdT-, and CD34-), and showing MLL rearrangement without MYC rearrangement at presentation. Both infants relapsed after months of morphologic and genetic remission. At relapse, the t(9;11) translocation was detected in both cases by spectral karyotyping. After the initial relapse, both cases followed a rapid and aggressive course. Literature search identified few similar cases, all expressed lambda surface immunoglobulin and showed MLL rearrangement (majority with the t(9;11) translocation). These cases show that B-ALL with MLL rearrangement, especially the t(9;11) translocation, can express a 'mature' B-cell phenotype and may represent a distinct subset. Identification of additional cases will further clarify the significance of MLL rearrangements in mature B-ALL.
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PMID:Mature B-cell acute lymphoblastic leukemia with t(9;11) translocation: a distinct subset of B-cell acute lymphoblastic leukemia. 1509 14

The present study has compared immunohistological marker expression profiles and genomic imbalances in seven African endemic Burkitt's lymphomas (eBLs) with those in ten European B-cell lymphomas with MYC rearrangement as shown by fluorescence in situ hybridization (FISH) analysis. eBLs showed a typical histomorphology and a homogeneous immuno-profile: CD10+, CD38+, CD77+, bcl-2-, and IgM+. Epstein-Barr virus (EBV) DNA was present in all cases. On comparative genomic hybridization (CGH), only three out of six eBLs showed imbalances (median number of imbalances = 2), with gains on chromosome 17 in two eBLs. The European lymphomas were all highly proliferating, with a Ki-67 index of at least 90%, and included seven with morphology typical of sporadic Burkitt's lymphoma (sBL) and three immunoblastic diffuse large B-cell lymphomas with MYC rearrangement (MYCre+DLBCL). In contrast to eBL, the immuno-profiles of the European lymphomas were less homogeneous and inconsistent for CD10, CD38, CD77, IgM and bcl-2 expression. EBV DNA was not detected. In five of seven sBLs, CGH showed a higher number of imbalances (median = 6), with recurrent gains on chromosome 1q (3/7) and losses on 12q and 17p (2/7), whereas all three MYCre+DLBCLs had fewer imbalances (median = 4), with gains on 17q in two of three lymphomas. It is concluded that eBL has a homogeneous immunohistology and few secondary genomic aberrations, whereas MYC-rearranged and highly proliferating European B-cell lymphomas are a heterogeneous group that includes sBL and a subgroup of diffuse large B-cell lymphomas.
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PMID:Homogeneous immunophenotype and paucity of secondary genomic aberrations are distinctive features of endemic but not of sporadic Burkitt's lymphoma and diffuse large B-cell lymphoma with MYC rearrangement. 1525 97

In 1974, a 28-year-old man presented with a 12 cm sized ulcerated tumor involving the middle third of the stomach, which was originally diagnosed as "lymphosarcoma". Clinical recurrence of the lymphoma resulted in rapidly progressing disease and the patient died 4 months after initial diagnosis. Retrospective work-up of the 29-year-old tumor blocks revealed the typical histologic appearance and phenotype (CD20, CD10, BCL-6 positive) of Burkitt's lymphoma (BL) with a proliferation rate of 95%. By fluorescence in situ hybridization (FISH). the tumor cells were shown to harbor an IGH-MYC fusion indicating the presence of the hallmark Burkitt-translocation t(8;14)(q24;q32). Considering the typical clinical features of BL requiring appropriate treatment regimes the case presented here highlights the importance of modern histopathologic and molecular cytogenetic techniques for the proper classification of such rare lymphomas presenting at atypical sites.
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PMID:Burkitt's lymphoma of the stomach: a case report with molecular cytogenetic analysis. 1529 67

A prompt distinction of Burkitt lymphoma (BL) versus diffuse large B cell lymphomas (DLBCL) has important clinical implications; however, this distinction can be difficult. We analyzed 74 adult gray zone and 10 reference pediatric BL using immunohistochemistry (Ki-67, CD10, bcl2, bcl6) and fluorescence in situ hybridization (FISH) for MYC, BCL2, and BCL6 breakpoints. Two algorithms for classification were followed: algorithm A used a two-step review by four hemato-pathologists and algorithm B a set of only biologic markers (Ki-67 > or = 90%, CD10+, bcl6+, bcl2-, MYC breakpoint+, BCL2 and BCL6 breakpoint-). Both algorithms categorized all reference cases as BL. In the adult group, algorithm A resulted in 21 adult BL and 52 DLBCL and algorithm B in 23 BL and 51 "non-Burkitt" lymphomas (nBL); 9 cases (12%) contained two different translocations and were categorized as nBL in algorithm B. Fifteen cases (20%) fulfilled the BL criteria of both algorithms. Although not considered as BL according to both algorithms, many other lymphomas showed nonetheless a phenotypic and/or genetic shift to BL. BL according to algorithm B was more homogeneous with respect to clinical presentation (gender and localization) than BL defined by algorithm A. Our data suggest that only a few cases of these gray zone lymphomas represent true de novo BL. Immunohistochemistry for Ki-67, CD10, and bcl2 with analysis of MYC and preferably also BCL2 and BCL6 may be advised as a marker panel for this diagnostic dilemma.
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PMID:Clinical, immunophenotypic, and genetic analysis of adult lymphomas with morphologic features of Burkitt lymphoma. 1600 5

Adult, de novo B-cell lymphomas meeting the WHO morphologic criteria for atypical Burkitt/Burkitt-like lymphoma cause diagnostic difficulty for pathologists because the genetic and clinical characteristics of this group of lymphomas have not been clearly defined. Thirty-one such lymphomas, designated as Burkitt-like lymphomas (BLL), were selected based on morphologic features and evaluated for immunophenotype, MYC and BCL2 status, and clinical features. Nine childhood Burkitt lymphomas (BL) and 87 adult, de novo diffuse large B-cell lymphomas (DLBL) were similarly evaluated for comparison. The BL group demonstrated uniform characteristics: all had Burkitt lymphoma morphology, an identical immunophenotype (positive for CD20, CD10, bcl-6, CD43, and p53; negative for CD138, CD23, bcl-2), high MIB-1 positivity, IGH/MYC translocation, no IGH/BCL2 translocation, and all patients were alive at the last follow-up. The BLL and DLBL groups were heterogeneous. Burkitt-like morphology alone correlated with decreased survival. IGH/MYC or IGL/MYC fusion was identified in 11 of 27 (41%) BLL and 4 of 76 (5%) DLBL and was associated with decreased survival in both groups. MIB-1 positivity did not correlate with morphology, MYC abnormalities, or survival. We propose that adult B-cell lymphomas with BLL morphology are a phenotypically and genetically heterogeneous group of aggressive lymphomas, biologically distinct from childhood BL. Until biologically accurate subgroups within this morphologically defined group are identified, it is appears that both recognition of BLL morphology and direct evaluation for the presence of MYC fusion to immunoglobulin genes are important for identification of adult patients with poorer prognosis than those with DLBL.
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PMID:Adult B-cell lymphomas with burkitt-like morphology are phenotypically and genotypically heterogeneous with aggressive clinical behavior. 1632 38

Among aggressive mature B-cell lymphomas, a reproducible morphological and immunohistological distinction between Burkitt's lymphoma and diffuse large B-cell lymphoma (centroblastic variant) is impossible in a substantial number of cases. The German reference centres for hematopathology collected 220 retrospective cases of aggressive mature B-cell lymphoma whose classification according to the current World Health Organisation criteria was reviewed. Gene expression analysis (Affymetrix) was performed in all cases and chromosomal translocations were determined using fluorescence in situ hybridization. Chromosomal losses and gains were analysed by matrix comparative genomic hybridisation and clinical data were successfully collected for most patients. The application of a novel bioinformatics method led to the identification of a stable and reproducible gene expression signature specific for Burkitt's lymphoma. A total of 44 cases were identified by this molecular signature [designated molecular Burkitt's lymphoma (mBL)]. These molecular Burkitt's lymphomas showed the morphology and immunohistology of classical or atypical Burkitt's lymphoma cases in 29 instances. However, 15 of the molecular Burkitt's lymphoma cases had the morphology of diffuse large B-cell lymphoma or could not be further specified. All molecular Burkitt's lymphomas showed an expression of BCL-6 and CD10, but a MYC translocation was not demonstrable in more than 10% of cases. Of significance is that more than 20% of the molecular Burkitt's lymphomas expressed BCL-2, although weakly in most instances. Our data demonstrate that: (1) the morphological, immunophenotypical and genetic spectrum of Burkitt's lymphoma is broader than previously expected, and (2) our molecular Burkitt's lymphoma signature enables a more precise and extended definition this lymphoma.
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PMID:[Burkitt's and Burkitt-like lymphoma. Molecular definition and value of the World Health Organisation's diagnostic criteria]. 1721 14

The distinction between Burkitt (BL) or atypical Burkitt/Burkitt-like lymphomas harboring a MYC translocation (MYC+) and diffuse large B-cell lymphomas (DLBCLs) with high proliferation fractions but without a MYC translocation (MYC-) can be difficult using standard morphologic and immunohistochemical criteria. Recently, unique gene expression profiles differentiating BL and DLBCL were reported and include higher transcript levels of T-cell leukemia-1 (TCL1) and CD38 and lower transcript levels of CD44 in MYC+ BL relative to MYC- DLBCL. We examined a cohort of 67 cytogenetically defined aggressive lymphomas using immunohistochemical techniques for expression of TCL1, CD38, and CD44 and found distinct expression patterns between MYC+ and MYC- tumors. Furthermore, these markers are better predictors of MYC status than combined staining for CD10 and BCL2. Thus staining for TCL1, CD38, and CD44 are useful ancillary tests to identify B-cell tumors for which confirmatory cytogenetic and/or fluorescent in situ hybridization studies assessing the status of the MYC locus should be pursued.
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PMID:Characteristic expression patterns of TCL1, CD38, and CD44 identify aggressive lymphomas harboring a MYC translocation. 1816 78

Burkitt lymphoma (BL) has a characteristic clinical presentation, morphology, immunophenotype and primary chromosomal aberration, that is, the translocation t(8;14)(q24;q32) or its variants. However, diagnostic dilemmas may arise in daily practice due to overlap of BL with subsets of other aggressive, mature B-cell lymphomas such as diffuse large B-cell lymphomas (DLBCL). Recently, two gene expression studies have described a distinct molecular profile for BL, but also showed the persistence of some cases intermediate between BL and DLBCL. An alternative approach to define BL is to consider (cyto)genetic data, in particular chromosomal abnormalities other than the t(8;14) or its variants. In this review the 'Mitelman Database of Chromosome Aberrations in Cancer,' harboring the majority of all published neoplasia-related karyotypes, was explored to define a cytogenetic profile of 'true' BL. This core subset of BL showed a very low complexity of chromosomal abnormalities with 40% of the cases having the IG-MYC fusion as the sole abnormality. In the remaining cases, additional recurrent but partially exclusive abnormalities included gains at chromosomes 1q, 7 and 12, and losses of 6q, 13q32-34 and 17p. Within the core subset, no differences were found between pediatric and adult patients. In addition, the genetic profile of the core subset was significantly different from BL with an 8q24 breakpoint not affecting one of the three immunoglobulin loci, BL with a translocation involving 18q21/BCL2, 3q27/BCL6 or 11q13/BCL1, additionally to a breakpoint at 8q24/MYC, and from other morphological types of lymphomas with an 8q24/MYC breakpoint. These groups showed a higher cytogenetic complexity than the core subset of BL. BL without a detectable 8q24/MYC breakpoint might be heterogeneous and deserves further studies. We suggest that, concordant with the WHO classification to be published in 2008, the diagnosis of BL should be restricted to cases with expression of CD10 and BCL6, absence or very weak expression of BCL2 protein, a homogeneously very high proliferation index and a proven IG-MYC translocation without evidence of a chromosomal translocation typical for other lymphoma entities. In addition, a high number of nonspecific cytogenetic abnormalities should suggest need for a critical review of the diagnosis of BL.
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PMID:Translocations involving 8q24 in Burkitt lymphoma and other malignant lymphomas: a historical review of cytogenetics in the light of todays knowledge. 1892 40


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