MALT lymphoma with t(14;18)(q32;q21)/IGH-MALT1 is characterized by strong cytoplasmic MALT1 and BCL10 expression

Mucosa-associated lymphoid tissue (MALT) lymphoma is specifically associated with t(11;18)(q21;q21), t(1;14)(p22;q32) and t(14;18)(q32;q21). t(11;18)(q21;q21) fuses the N-terminus of the API2 gene to the C-terminus of the MALT1 gene and generates a functional API2-MALT1 product. t(1;14)(p22;q32) and t(14;18)(q32;q21) bring the BCL10 and MALT1 genes respectively to the IGH locus and deregulate their expression. The oncogenic activity of the three chromosomal translocations is linked by the physiological role of BCL10 and MALT1 in antigen receptor-mediated NFkappaB activation. In this study, MALT1 and BCL10 expression was examined in normal lymphoid tissues and 423 cases of MALT lymphoma from eight sites, and their expression was correlated with the above translocations, which were detected by molecular and molecular cytogenetic methods. In normal B-cell follicles, both MALT1 and BCL10 were expressed predominantly in the cytoplasm, high in centroblasts, moderate in centrocytes and weak/negative in mantle zone B-cells. In MALT lymphoma, MALT1 and BCL10 expression varied among cases with different chromosomal translocations. In 9/9 MALT lymphomas with t(14;18)(q32;q21), tumour cells showed strong homogeneous cytoplasmic expression of both MALT1 and BCL10. In 12/12 cases with evidence of t(1;14)(p22;q32) or variants, tumour cells expressed MALT1 weakly in the cytoplasm but BCL10 strongly in the nuclei. In all 67 MALT lymphomas with t(11;18)(q21;q21), tumour cells expressed weak cytoplasmic MALT1 and moderate nuclear BCL10. In MALT lymphomas without the above translocations, both MALT1 and BCL10, in general, were expressed weakly in the cytoplasm. Real-time quantitative RT-PCR showed a good correlation between MALT1 and BCL10 mRNA expression and underlining genetic changes, with t(14;18)(q32;q21)- and t(1;14)(p22;q32)-positive cases displaying the highest MALT1 and BCL10 mRNA expression respectively. These results show that MALT1 expression pattern is identical to that of BCL10 in normal lymphoid tissues but varies in MALT lymphomas, with high cytoplasmic expression of both MALT1 and BCL10 characterizing those with t(14;18)(q32;q21).     

Primary macroglobulinemia with t(11;18)(q21;q21)

These are the first cases of primary macroglobulinemia (PMG) with t(11;18)(q21;q21) reported in the literature. The first case was a 77-year-old man with macroglobulinemia (serum IgM: 8.36 g/dL). Abnormal lymphoid cells were detected in the blood and bone marrow. Immunologic and karyotypic analyses revealed that abnormal cells were positive for surface IgM-k, CD19, and CD20, negative for CD5 and CD10, and all had a t(11;18)(q21;q21). The second case was a 57-year-old woman with macroglobulinemia (serum IgM: 12.0 g/dL). Abnormal lymphoid cells were detected in blood and marrow, and cells were positive for surface IgM-lambda, CD19, and CD20, and negative for CD5 and CD10. Plasma cells bearing cytoplasmic IgM-lambda were increased in pleural fluid. Karyotyping demonstrated t(2;11;18)(q21-23;q21;q21). Rearrangements within BCL2 and YES genes located at 18q21 were not detected. Sixteen other cases with t(11;18)(q21;q21) have been reported in marginal zone B-cell lymphoma. Therefore, our report is in agreement with the finding that part of primary macroglobulinemia is a variant of marginal zone B-cell lymphoma.     

t(18;22)(q21;q11) with rearrangement of BCL2 as a possible secondary change in a lymphocytic lymphoma

We report a lymphocytic lymphoma showing a combination of two characteristic neoplasia-associated chromosomal changes: trisomy 12, commonly observed in chronic lymphocytic leukemia and lymphocytic lymphoma, and t(18;22)(q21;q11), a variant form of the t(14;18)(q32;q21) found in most follicular lymphomas. Southern blot analysis was performed using probes for the 5' end of the BCL2 gene (18q21) and for the J lambda as well as C lambda immunoglobulin genes (22q11). With these two probes, a unique rearranged fragment was detected. Thus the t(18;22)(q21;q11) can be considered as a variant translocation of t(14;18)(q32;q21). The karyotypic analysis supports the assumption that in our case trisomy 12 occurred first, and t(18;22) appeared during tumor progression as part of the clonal evolution. This is at variance with the typical t(14;18), which has never been found to occur as a secondary change.     

t(11;18)(q21;q21) is a recurrent chromosome abnormality in small lymphocytic lymphoma.

We have identified two cases of previously untreated, small lymphocytic lymphoma with extranodal involvement, which had a reciprocal translocation, t(11;18)(q21;q21), as the sole cytogenetic abnormality. These two cases are remarkably similar to two previously reported cases carrying this translocation with regard to clinical features, cytogenetic abnormality, histologic subtype, and immunophenotype. Molecular genetic analysis of these two cases revealed clonal gene rearrangement of the IGH locus but only germline configuration of the BCL2 oncogene at 18q21 when probes and conditions that usually identify BCL2 rearrangement in lymphomas were used. Lymphomas bearing an (11;18) rearrangement appear to make up a phenotypically identifiable subgroup. Identification of the genes at the translocation breakpoints will be important.     

Follicular lymphoma with trisomy 18 and over-expression of BCL2 in the absence of t(14;18)(q32;q21)

A 66-year-old female who presented with cervical lymphadenopathy and splenomegaly was found to have large B-cell lymphoma on lymph node biopsy. However, trephine biopsy revealed involvement of the marrow by follicular lymphoma, and cytogenetic study showed an abnormal clone with 47,XX,+18.     

Molecular mapping of the chromosome 11 breakpoint of t(11;17)(q13;q21) in a t(11;14)(q13;q32)-positive B non-Hodgkin's lymphoma

The FAU gene is the cellular homologue of the viral FOX sequences in the genome of the Finkel-Biskis-Reilly murine sarcoma virus (FBR-MuSV); the viral FOX sequences have been shown to increase the transforming capacity of FBR-MuSV in vitro. The human FAU gene has recently been isolated, characterized, and mapped to chromosome band 11q13. Here, we report results of fluorescence in situ hybridization (FISH) analysis which indicate that the FAU gene maps proximally to the putative oncogene BCL1 at 11q13. Furthermore, we identified a t(11;17)(q13;q21) translocation in tumor cells of a t(11;14)(q13;q32)-positive B-cell non-Hodgkin's lymphoma patient by FISH analysis using a FAU containing cosmid clone as molecular probe and by double-colour chromosome painting analysis using chromosome 11- and chromosome 17-specific painting probes. The position of the chromosome 11 breakpoint of the t(11;17) translocation was pinpointed to a human DNA region around the FAU gene of about 40 kbp. © 1993 Wiley-Liss, Inc.     

A novel t(2;6)(p12;q23) appearing during transformation of follicular lymphoma with t(18;22)(q21;q11) to diffuse large cell lymphoma

Follicular lymphoma is characterized genetically by t(14;18)(q32;q21), whereas t(18;22)(q21;q11), a rare variant form of t(14;18), has been preferentially observed in chronic lymphocytic leukemia (CLL). We describe here an unusual case of follicular lymphoma with a t(18;22)(q21;q11), that progressed to diffuse large cell lymphoma with a novel t(2;6)(p12;q23). Spectral karyotyping revealed that add(2)(p12) and add(6)(q23) were derived from a t(2;6)(p12;q23). Fluorescence in situ hybridization analysis confirmed rearrangements of the BCL2 gene at 18q21 and the BCL6 gene at 3q27. Our results indicate that a reciprocal translocation involving 6q23 could be implicated in the progression of follicular lymphoma and that t(18;22) may have a specific role in the pathogenesis of follicular lymphoma as well as CLL.     

The 11q23 breakpoint in acute leukemia with t(11;19)(q23;p13) is distal to those of t(4;11), t(6;11) and t(9;11).

Thirteen cosmid probes were mapped on the long arm of chromosome 11 between 11q22 and 11q24 by nonradioactive in situ hybridization. Starting with these localizations and those of other probes mapped to 11q23, four acute leukemias with translocations involving 11q23 were studied with the same method. The translocation breakpoints of the t(4;11)(q21;q23), t(6;11)(q27;q23), t(9;11)(p21-p22;q23), and t(11;19)(q23;p13) were confirmed to be distal to CD3D. The probe cC111-304 was proximal to the t(11;19) breakpoint while distal to the breakpoints of the other rearrangements. In view of the diversity of chromosomal abnormalities involving band 11q23, our finding extends the molecular heterogeneity of the breakpoint localization in leukemias with rearrangements involving 11q23.     

t(11;18)(q21;q21) may delineate a spectrum of diffuse small B-cell lymphoma with extranodal involvement

We describe a patient with stage IV non-Hodgkin's lymphoma (NHL) and a t(11;18)(q21;q21) translocation. He presented with a gastric small B-cell lymphocytic lymphoma, expressing IgAL immunoglobulins without expression of CD10, CD5, and CD23 antigens. The lymphoma was the final development of a 6-year history of a monoclonal IgAL increase complicated by severe renal failure due to membranoproliferative glomerulonephritis. The clinical, histological, immunologic, and cytogenetic features of this patient are very similar to those observed in the five other patients with t(11;18) reported to date. This translocation therefore seems to delineate a new subtype of diffuse small B-cell lymphoma with involvement of mucosal sites. Involvement of the BCL2 oncogene on 18q21 could not be detected using molecular techniques with 5′ as well as 3′ BCL2 probes, indicating that other, so far unknown, genes relevant to lymphoid differentiation could be located in 18q21 and 11q21. © 1993 Wiley-Liss, Inc.     

Molecular cloning of a t(11; 14)(q13;q32) translocation breakpoint centromeric to the BCLI-MTC

In B-cell malignancies, the t(11;14)(q13;q32) at the 11q13 BCLI locus is characterized by a scattering of breakpoint sites along a 100 kb genomic region, between the BCLI major translocation cluster (MTC) and the PRADI (also termed cyclin DI or CCNDI) gene. Recently, the 11q13 breakpoint region was extended on both sides, centromeric to the MTC and telomeric to PRADI. We report here the molecular cloning of a new t(11;14) breakpoint site, 20 kb centromeric to the MTC, from a patient with prolymphocytic leukemia. We subcloned a non-repetitive DNA fragment near the breakpoint and mapped this new 11q13 probe (pHOII_c) relative to already identified breakpoint sites, using long- and short-range physical mapping within the BCLI locus. Rearrangements in the BCLI locus are associated with deregulation of the PRADI gene, which is often overexpressed, particularly in mantle-cell malignancies. The detectable but weak PRADI expression in the case we present suggests that this breakpoint centromeric to the MTC still lies inside the BCLI locus boundaries. We think that attention should be focused on this region centromeric to the BCLI-MTC, where the investigation of previously unidentified translocations may increase understanding of the PRADI gene deregulation in t(11;14) associated pathologies.     

Four cases of follicular lymphoma with t(14;18)(q32;q21) and t(3;4)(q27;p13) with LAZ3 (BCL6) rearrangement.

We report four cases of follicular lymphoma with both t(14;18)(q32;q21) and the newly characterized t(3;4)(q27;p13). Molecular investigation confirmed LAZ3 (BCL6) rearrangement for all patients. The 3q27 aberrations have been rarely described in low-grade lymphomas and may represent secondary events whose implication remains to be elucidated.     

t（11;18）（q11;q23）一家系

先证者　男 ,30岁 ,表型正常。婚后 3年 ,其妻怀孕 5次 ,均在孕 2～ 3个月自然流产 ,妇科检查正常。夫妇非近亲结婚。患者外生殖器正常。精液检查精子数量正常。细胞遗传学检查 :外周血细胞染色体观察 ,常规外周血淋巴细胞培养 ,G显带分析30个细胞 ,先证者核型为 46 ,XY,t(11;18) (11pter→ 11q11∷18q2 3→ 18qter;18pter→ 18q2 3∷ 11q11→ 11qter) ,其妻染色体核型正常。先证者性细胞联会复合体 (synaptonemal complex,SC)观察 ,方法参照文献 [1]。睾丸活检微铺展的 SC电镜观察 ,分析 30个精母细胞 (从早粗线期到晚粗线期 )中 SC图…     

Unique three-way translocation, t(3;14;18)(q27;q32;q21), in follicular lymphoma

A 43-year-old woman was diagnosed as having stage IV follicular lymphoma. Phenotypically, the lymphoma cells were CD5(-), CD10(+), CD19(+), CD20(+), CD23(-), HLA-DR(+), and IgM-lambda(+). Conventional chromosomal analysis showed a three-way t(3;14;18)(q27;q32;q21) in the lymphoma cells, which was confirmed by spectral karyotyping (SKY) and fluorescence in situ hybridization (FISH). Immunohistochemistry revealed that both BCL2 and BCL6 proteins were expressed in the lymphoma cells, whereas only the BCL6 gene, and not the BCL2 gene, was rearranged by Southern blotting. The patient received combination chemotherapy and has been well for 3 years. This is the first reported case showing a three-way translocation involving 2 major lymphoma-specific abnormalities, 3q27 and t(14;18)(q32;q21).