Pre-B-cell leukemia with a t(8; 14) and a t(14; 18) translocation is preceded by follicular lymphoma

We have performed gene rearrangement studies on the leukemic blasts of a patient with acute pre-B-cell leukemia. The patient had a 5 year history of follicular lymphoma, which developed into acute pre-B-cell leukemia. The leukemic blasts revealed a karyotype with two translocations, t(8; 14) and t(14; 18), characteristic for Burkitt's lymphoma and follicular lymphoma. The cells are TdT positive, do not possess surface immunoglobulin, and they show immunoglobulin gene rearrangement. The mu heavy chain and kappa light chain constant (C mu and C kappa) loci are deleted, while the gamma and lambda light chain constant (C gamma and C lambda) region genes are rearranged. Both alleles of the heavy chain joining segment (JH) are rearranged on chromosome 14q+, one of them with the bcl-2 oncogene from chromosome 18. The breakpoint of the t(14; 18) translocation occurs in the major breakpoint cluster region in the 3' untranslated region of bcl-2. On chromosome 8 a c-myc rearrangement was mapped immediately 5' to the c-myc first exon in a region involved in sporadic Burkitt lymphoma. The data are consistent with our previous hypothesis on the evolution of B-cell malignancies: a rare pre-B cell develops a t(14; 18) translocation during immunoglobulin VDJ joining that results in an expansion of a follicular lymphoma clone carrying an activated bcl-2 gene. Within the clone of pre-B cells a second translocation, t(8; 14), occurs during heavy chain isotype switching that results in the deregulation of the c-myc involved in the translocation.     

bcl-2 translocation in Japanese B cell lymphoma: novel bcl-2 translocation with immunoglobulin heavy chain diversity segment

Breakpoints of a lymphoma case with bcl-2 gene rearrangement that did not show comigration of immunoglobulin (Ig) heavy chain joining (JH) fragment were cloned. Sequence analysis revealed that the translocation broke the 3' side of the Ig heavy chain diversity (DH) segment at the heptamer recombination signal and each end was ligated to the bcl-2 locus. Since Southern blot demonstrated that both alleles of JH were rearranged, this translocation was suggested to have occurred at the step of VH-DH, or DH-DHJH recombination, one step later than that of DH-JH recombination where the common pattern of bcl-2 rearrangement generally occurs. Cases that showed comigration with JH fragment were also studied by polymerase chain reaction with 5' bcl-2 oligomer and 3' JH consensus anti-sense oligomer since it has been demonstrated that bcl-2 translocation at the major breakpoint clustering region (mbr) in American cases clusters within an about 150 bp region in the mbr. The results demonstrated that four out of five cases studied were amplified, indicating that the same clustering mechanism exists for Japanese cases. The present study, together with our previous report on Ig kappa-bcl-2, indicated that bcl-2 translocation in Japanese B cell lymphomas might occur at a later stage of B cell development, as compared with that in American cases. Less involvement of bcl-2 in Japanese B cell lymphoma may also be in part explainable by low susceptibility to bcl-2 rearrangement at the step of DH-JH recombination.     

Involvement of the bcl-2 gene in Hodgkin's disease

A major obstacle to investigations of Hodgkin's disease is the paucity of malignant cells, i.e., Reed-Sternberg cells and their variants, in tissues of patients with this disease. Consequently, the pathogenesis, cell of origin, and clonality of this relatively frequent lymphoma have remained unresolved. Results of recent studies suggest that in some instances Reed-Sternberg cells carry rearranged immunoglobulin heavy-chain joining region (JH) loci as well as chromosomal translocations involving band 14q32. Prompted by these findings, we sought to determine if the t(14;18) (q32;q21) translocation of follicular, non-Hodgkin's B-cell lymphoma was associated with Hodgkin's disease. To detect the possible t(14;18) (q32;q21) translocation within the rare malignant cells of Hodgkin's disease, we amplified sequences created by the t(14;18) translocation using the polymerase chain reaction (PCR). With this approach, DNA sequences carrying the direct fusion of the major breakpoint region of the candidate oncogene, bcl-2, derived from chromosome 18q21, with JH on chromosome 14q32 can be detected in as few as one in 10(5)-10(6) cells. In the present study, joined bcl-2/JH sequences were detected in tissues involved by Hodgkin's disease in 17 of 53 (32%) patients. The frequent association of bcl-2 translocation with Hodgkin's disease suggests that this oncogene has a role in the pathogenesis of Hodgkin's disease. That bcl-2 is involved in a major class of lymphoma in addition to follicular lymphoma implies a role for additional factors responsible for generating the two distinctive clinical and pathologic disease states.     

BCL-2 gene in lymphocytic malignancy

In t(14;18) (q32;q21) lymphomas, bcl-2 gene is activated by the juxtaposition of immunoglobulin (Ig) gene. The fused bcl-2-Ig gene generates chimeric mRNAs which consist of bcl-2 at 5' portion and Ig at 3' portion. Chimeric mRNA does not disrupt the bcl-2 coding frame of 239 amino acid polypeptide. Bcl-2-Ig transgenic mice demonstrated the extended B cell survival and the follicular lymphoproliferation, but they did not develop a malignancy until 25 weeks. Ten percent of them, however, developed malignant diffuse large-cell lymphomas after a long latency. Forty percent of these malignancies demonstrated the c-myc rearrangement, indicating that multiple step changes are required for malignant transformation in bcl-2 activated cells. Study on the bcl-2 gene rearrangement in Japanese B cell lymphoma and B-CLL revealed that 10 out of 32 cases of follicular lymphoma (31%), 5 out of 56 cases of diffuse lymphoma (9%) and 2 out of 30 cases of B-CLL (7%) were rearranged. Less frequency of B cell lymphoma, particularly follicular lymphoma in Japan might be partly due to the less bcl-2 involvement than in American cases. The ratio of bcl-2 involvement in B-CLL is not significantly different between Japan and U.S.A.. bcl-2 rearrangement at 5' promoter region is noted for Japanese B-CLL which was demonstrated for American cases. The clinical application of polymerase chain reaction for bcl-2 translocation was also discussed.     

Concurrent activation of c-myc and inactivation of bcl-2 by chromosomal translocation in a lymphoblastic lymphoma cell line

We have characterized a chromosomal translocation in a cell line (SU-DUL5) established from a patient with lymphoblastic lymphoma in which the c-myc gene on chromosome 8 was juxtaposed to a t(14;18). Cytogenetic analysis of this cell line showed 14q+, 18q-, and 8p+q+ marker chromosomes in the absence of t(14;18). Genomic Southern blot analysis showed juxtaposition of the immunoglobulin heavy chain joining region (JH) with chromosome 18 near the minor breakpoint cluster region (mcr) of the bcl-2 gene. There was also a rearranged c-myc gene detectable with a 5' c-myc probe. Molecular cloning studies showed that the c-myc gene was joined to chromosome 18 DNA. Nucleotide sequence analysis of cloned breakpoint DNA revealed that the crossover between chromosomes 8 and 18 occurred at the 3' end of the bcl-2 gene resulting in replacement of the bcl-2 gene on the 14q+ chromosome with the c-myc gene. As a result of this translocation the SU-DUL5 cell line contains no detectable bcl-2 mRNA or protein but has abundant levels of c-myc mRNA. Our data suggest that bcl-2 inactivation occurred simultaneously with c-myc translocation in a B cell lymphoblastic lymphoma.     

Translocation (14;19)(q32;q13.1) in a Young Patient who Developed a Large Cell Lymphoma after an Initial Diagnosis of CLL

A translocation (14;19)(q32;q13.1) was found in a 31 year old man with a large cell lymphoma which had evolved from chronic lymphocytic leukaemia (CLL). Molecular analysis showed a monoclonal proliferation of B cells with rearrangement of the immunoglobulin (Ig) heavy and kappa light chain genes, and of the bcl-3 gene on chromosome 19q. Nine cases with t(14;19) from the literature were reviewed; B cell lymphoma had been diagnosed in eight and acute biphenotypic leukaemia in one of these cases. Four had transformed from CLL to a more aggressive disease, as in the present case. Two out of seven patients as well as the present one, with t(14;19) and CLL were young (less than 40). The t(14;19) is usually associated with other cytogenetic abnormalities; in our case a (15;16)(q15;p13) translocation was found and appears to be an additional nonrandom aberration in t(14;19) disorders.     

Chromosome 14 translocation in african and north american burkitt's lymphoma

Two established North American Burkitt lymphoma cell lines were studied by chromosomal banding techniques. The SU-AmB-1 line previously shown to be negative for the Epstein-Barr virus (EBV) was found to have, among other changes, a translocation from the long arm (q) of chromosome 8 onto 14q. The SU-AmB-2 line, which contains the EBV genome, also displayed the same 8/14 translocation. These results were compared with data from three EBV-positive tumor cell lines derived from patients with African Burkitt's lymphoma. Our findings indicate that a translocation from 8q onto 14q occurs in both African and North American Burkitt lymphomas, and that this abnormality apparently is not related directly to EBV. This chromosome translocation therefore may be an important event in the development of human lymphocytic malignancy, analogous to the occurrence of the Philadelphia chromosome rearrangement in chronic myelogenous leukemia.     

Bcl-2 Gene and Prognosis of B-cell Lymphoma

Both the polymerase chain reaction (PCR) and Southern blot analysis were used to detect bcl-2 gene rearrangement in B-cell lymphoma. Recent molecular studies have shown that the translocation of karyotypic abnormalities t(14;18) results in the juxtaposition of the candidate proto-oncogene bcl-2 on chromosome 18 with the immunoglobulin heavy-chain locus on chromosome 14. We detected the bcl-2 rearrangement in three of six follicular lymphomas (50%), two of five follicular and diffuse lymphomas (40%), one of 13 diffuse medium-sized cell lymphomas (7.7%) and two of 33 diffuse large cell lymphomas (6.0%) through Southern blot analysis. With PCR, the rearrangement was demonstrated in five of eight follicular (63%), three of five follicular and diffuse (60%), seven of 36 diffuse large cell lymphomas (19%) and two of 13 diffuse medium-sized lymphomas (15%). Diffuse large cell lymphomas with bcl-2 rearrangement detected by PCR have a good prognosis as do cases of follicular lymphoma The bcl-2 gene is closely related to follicular lymphoma as described in previous reports and has general prognostic importance in diffuse large cell lymphoma of B cell type.     

A variant translocation t(2;18) in follicular lymphoma involves the 5' end of bcl-2 and Ig kappa light chain gene

We have examined three cases of human lymphoma bearing a t(2;18)(p11;q21) chromosome translocation. The bcl-2 gene appeared to be rearranged in all three cases and breakpoints were clustered in the 5' flanking region of the gene. In all three cases, bcl-2 was juxtaposed to J segments of the Ig kappa gene. This juxtaposition of the bcl-2 and Ig kappa genes is very similar to the variant chromosome translocations of Burkitt lymphoma that juxtapose the c-myc locus to IgL genes.     

Mantle Cell Lymphoma: An Update

Mantle cell lymphoma is a distinctive pathologic entity that incorporates the previous histopathologic categories of centrocytic lymphoma and lymphocytic lymphoma of intermediate differentiation. These lymphomas are characterized by common histologic and immunologic characteristics that suggest derivation from the follicular mantle zone. Mantle cell lymphomas are characterized by the t(11;14) (q13;q32) translocation and its molecular counterpart bcl-1 rearrangement. This translocation activates a gene called BCL-1/PRAD-1. The identification of the BCL-1 gene product as a cyclin has added a new dimension to our understanding of the variety of mechanisms involved in lymphomagenesis.     

The detection of specific gene rearrangements in non-Hodgkin's lymphoma using the polymerase chain reaction.

Characteristic gene rearrangements are present in most non-Hodgkin's lymphomas (NHL). These are usually detected by Southern blotting techniques. In this study, the ability of the polymerase chain reaction (PCR) to detect the t(14;18) chromosomal translocation and immunoglobulin heavy chain (IgH) gene rearrangement was evaluated. DNA from 14 follicular and 42 diffuse B-cell lymphomas was examined using oligonucleotide primers specific for opposing sides of the IgH gene rearrangement on chromosome 14 (towards conserved VH and JH sequences) and opposing sides of the t(14;18) chromosomal translocation (towards the major breakpoint region of the bcl-2 gene on chromosome 18 and conserved JH sequence on chromosome 14). The t(14;18) translocation was detected in 57% of follicular lymphomas and 21% of diffuse B-cell lymphomas. Clonal IgH gene rearrangements using PCR were detected in 50% follicular and 52% of the diffuse lymphomas. Either or both of these rearrangements were detected in 93% follicular and in 59% of diffuse lymphomas. PCR is a rapid and easy technique that can detect the abnormal rearrangement of the bcl-2 gene and clonal IgH rearrangement, indicating the presence of lymphoma. This may be of benefit in monitoring response to therapy and in predicting prognosis in this disease.     

The establishment of Epstein-Barr virus nuclear antigen-positive (SP-50B) and Epstein-Barr virus nuclear antigen-negative (SP-53) cell lines with t(11;14)(q13;q32) chromosome abnormality from an intermediate lymphocytic lymphoma

Two lymphoma cell lines, SP-50B and SP-53, were established from peripheral blood of a 58-year-old woman with leukemic conversion of intermediate lymphocytic lymphoma. These cell lines grew in suspension with or without forming clumps of cells. SP-50B was morphologically similar to the common Epstein-Barr (EB) virus-transformed lymphoblastoid cell lines and was positive for EB virus nuclear antigen (EBNA), whereas SP-53 closely resembled the patient's lymphoma cells and was negative for EBNA. Both cell lines expressed the same phenotypic markers as original lymphoma cells (CpIg+, SmIg+, OKIa1+, Leu12+) and possessed t(11;14)(q13;q32) chromosome translocation. These results indicate that although morphologically different, SP-50B and SP-53 were both derived from patient's lymphoma cells. The long-term cultivation of EBNA-positive and EBNA-negative B-cell lymphoma lines from a single donor has not been previously reported. These cell lines would provide useful tools for studying the oncogenic role of EB virus and bcl-1 oncogene that is located on chromosome 11q13.     

Nonrandom rearrangement of chromosome 14 at band q32.33 in human lymphoid malignancies with mature B-cell phenotype

Chromosomes were studied in 61 patients with differentiated B-cell malignancies including 21 with non-Hodgkin's lymphoma (NHL), three with hairy cell leukemia (HCL), eight with Waldenstr?m's macroglobulinemia (WM), and 29 with plasma cell disorder. Chromosomally abnormal clones were identified in 35 of 61 patients studied: all with NHL, all with HCL, three of eight with WM, and eight of 29 with plasma cell disorder. The most recurrent chromosomal abnormality, observed in 26 of the 35 patients whose chromosomes were abnormal, was a rearrangement involving chromosome 14, in which an additional segment was attached at band 32 in the long arm to form a 14q+ marker chromosome. This rearrangement was seen in 17 patients with NHL, three with HCL, one with WM, and five with plasma cell disorder. In NHL, the rearrangement correlates with histological subclasses: t(14;18) in all four patients with malignant lymphoma (ML)-follicular, mixed small cleaved and large cell; t(8;14) or its variant form, t(8;22), in all six with ML-small noncleaved cell; and t(11;14) in two of three with ML-diffuse, mixed small and large cell. A t(14;18) was also found in each patient with ML-diffuse, large cell, WM, and multiple myeloma, and a variant three-way translocation, t(5;18;14) (q13;q21;q32), in one with ML-diffuse, small cleaved cell. The donor sites for these 14q+ were assigned to oncogene loci: c-myc (8q24), bcl-1 (11q13), and bcl-2 (18q21). Moreover, the donor sites were also located near immunoglobulin light chain gene loci in each patient with leukemic ML-diffuse, mixed small and large cell, t(2;14) (p13;q32.3), and HCL, t(14;22)(q32.3;q11.2). These findings suggest that chimeric DNA formation, not only between an immunoglobulin gene and a certain oncogene, but also between the IgH gene and one of the IgL genes may be potentially relevant in malignant B-cell proliferation.     

BCL-6 and other genomic alterations in non-Hodgkin's lymphoma (NHL).

This study reports on the frequency and disease association pattern of a number of gene rearrangements in a large panel of lymphoid tumours (n = 94). We detected the t(11;14) translocation, involving rearrangement of the BCL-1 locus, in 60% of mantle cell lymphomas. The BCL-2 gene, located at band 18q21, was rearranged in 42% of follicle centre lymphomas (FCL) and in 15% of diffuse large B-cell (DLBC) lymphomas. In this study, 80% of the c-MYC rearrangements were detected in aggressive diffuse lymphoma subsets but, interestingly, 9% of FCL showed involvement of t(8q24) translocation. In our study, rearrangements of the BCL-6 gene at band 3q27 were found in 31% of DLBC lymphomas. Interestingly, 50% of the BCL-6 rearrangement positive lymphoma cases had coexisting gene rearrangements involving all of the aforementioned gene loci. The molecular dissection of these genes will improve our understanding of the genesis of the diverse clinicopathological subtypes.     

Cyclin D1 protein expression in mantle cell lymphoma

BACKGROUND: The t(ll;14)(ql3;q32) is a chromosomal abnormality usually associatedwith mantle cell (centrocytic) lymphomas, although it has occasionallybeen reported in other chronic lymphoproliferative disorderssuch as chronic lymphocytic leukemia, prolymphocytic leukemia,splenic lymphoma with villous lymphocytes, and multiple myeloma.This abnormality results in the translocation of the bcl-1 oncogenefrom chromosome 11 to the immunoglobulin heavy chain locus onchromosome 14. The bcl-1 oncogene is a member of the cyclingene family, and high levels of cyclin Dl mRNA are consistentlyfound in malignant B cell proliferations with t(ll;14). PATIENTS AND METHODS: We examined cyclin D1 protein expression in 33 patients withlow grade lymphoproliferative disorders and 2 patients withreactive hyperplasias by Western blot analysis using a polyclonalantibody. RESULTS: 8/11 mantle cell lymphomas, 0/11 chronic lymphocytic leukemias,0/4 hairy cell leukemias, 0/2 Sezary syn-drome, 0/2 monocytoidB-cell lymphomas, 0/3 follicular lymphomas, and 0/2 reactivehyperplasias had overexpres-sion of cyclin Dl. Cytogenetic analysiswas performed in four cases of mantle cell lymphoma; three ofthese cases had the t(ll;14), one of which was hypotetraploidwith two copies of t(ll; 14). Immunophenotypically, all casesof mantle cell lymphoma and chronic lymphocytic leukemia hadcoexpression ofCD5 and CD20. CONCLUSION: Mantle cell lymphoma may be difficult to discriminate from chroniclymphocytic leukemia, a more indolent disease, on morphologicand immunophenotypic grounds. Our findings suggest that analysisof cyclin Dl protein expression may be helpful in differentiatingmantle cell lymphomas from other low grade lymphoproliferativedisorders. cyclin D1, bcl-1, mantle cell lymphoma, centrocytic lymphoma, t(ll;14)(ql3;q32), low grade lymphoproliferative disorders     

Rearrangement of immunoglobulin, T-cell receptor, and bcl-2 genes in malignant lymphomas in Hong Kong

The pattern of malignant lymphomas in the Hong Kong Chinese population is characterized by a low incidence of Hodgkin's disease and follicular lymphomas. The authors studied the immunoglobulin (Ig), T-cell receptor (TCR), and bcl-2 gene rearrangement in 62 cases of malignant lymphoma in this population by Southern blot hybridization. Two cases of Hodgkin's disease showed no rearrangement of the Ig and TCR genes. All 42 cases of B-cell lymphoma had Ig heavy chain (JH) rearrangement with or without additional rearrangement of the light chains (C kappa and C lambda). One case of diffuse B-cell lymphoma had additional T-cell receptor beta-chain (C beta) rearrangement. Sixteen of 18 cases of T-cell lymphoma had C beta rearrangement, and one case of T-lymphoblastic lymphoma had additional JH rearrangement. Two of eight (25%) cases of follicular lymphoma but only one of the 34 (2.9%) cases of diffuse B-cell lymphoma had bcl-2 rearrangement that was detected by pFL-1 probe. None of the 62 cases showed bcl-2 rearrangement using the pFL-2 probe. In conclusion, the Ig and TCR gene rearrangement pattern of the lymphomas found in Hong Kong correlates well with the T-cell and B-cell lineage, which is similar to reports in the white population. However, the incidence of bcl-2 gene rearrangement in follicular B-cell lymphoma is lower than that reported in the US but comparable with that in Japan.     

Establishment of a new human B cell line carrying t(11;14) chromosome abnormality

A new human cell line, SP-49, was established from the peripheral blood of a patient with leukemic conversion of diffuse lymphoma, medium-sized cell type. SP-49 cells were shown to have intracytoplasmic and surface immunoglobulin and Leu-12 antigen, but were negative for Epstein-Barr virus nuclear antigen. Chromosome analysis demonstrated that SP-49 had t(11;14) chromosome translocation involving 11q13 and 14q32, where oncogene bcl-1 and immunoglobulin heavy chain gene, respectively, were reportedly located.     

Juxtaposition of human bcl-2 and immunoglobulin lambda light chain gene in chronic lymphocytic leukemia is the result of a reciprocal chromosome translocation between chromosome 18 and 22

The human bcl-2 gene is a oncogene candidate which is involved in the t(14;18) translocation specifically associated with follicular and diffuse B cell lymphomas. This translocation deregulates bcl-2 gene expression by placing it into immunoglobulin heavy chain locus (IgH). We have recently reported a case of chronic lymphocytic leukemia (CLL 1446) carrying a unique bcl-2 gene rearrangement with the immunoglobulin lambda light chain (Ig lambda) gene. This juxtaposition of the bcl-2 and Ig lambda genes resembles a variant chromosome translocation in Burkitt's lymphoma, although karyotype data of CLL 1446 is not available. In this paper, we completed the structural analysis of the bcl-2/Ig lambda gene rearrangement in CLL 1446 by cloning the corresponding partner of the rearrangement. This revealed that the juxtaposition of the bcl-2 and Ig lambda genes is a result of a reciprocal chromosome translocation between chromosomes 18 and 22 with deletions of 2 and 15 bp, respectively. Although a conserved immunoglobulin recombination signal (7mer-9mer) was absent around the breakpoint on chromosome 18, nonamer-like sequence was recognized within the deleted region at the breakpoint on chromosome 22. No extranucleotide was associated with both joining sites of the t(18;22) translocation. This is in sharp contrast to the t(14;18) translocation involving IgH locus in which the presence of extranucleotides is common and correlates well with the presence and absence of extranucleotides on V-(D)-J joining of IgH and light chain (L) genes, respectively. The data together suggest that the mechanism responsible for the physiological rearrangement of immunoglobulin genes is involved in this translocation.