t(9;14)(p13;q32) involving the PAX-5 gene: a unique subtype of 14q32 translocation in B cell non-Hodgkin's lymphoma

Newly identified t(9;14)(p13;q32) is a subtype of the well-defined 14q32 translocation and is closely associated with lymphoplasmacytic lymphoma (Revised European-American Classification of Lymphoid Neoplasms). The analysis of the breakpoint of t(9;14) unraveled its molecular structure as being the recombination of the PAX-5 gene on 9p13 with IgH locus located on 14q32. The molecular event does not seem to cause structural alteration of the protein product of PAX-5 and, instead, its deregulation is most likely the essential outcome of this translocation. In vitro experiments have shown that the overexpression of PAX-5 resulted in enhanced proliferation of B cells, implicating its potential capacity for lymphomagenesis. PAX-5 is crucial during most developmental stages of B cells mainly through regulating the expression of a variety of genes. Therefore, elucidating the nature of the altered expression of these downstream genes as well as the PAX-5 gene itself would be indispensable in clarifying the precise mechanism of lymphomagenesis caused by t(9;14).     

Intravascular large B-cell lymphoma associated with t(14;19)(q32;q13) translocation

We report a 59-year-old man with intravascular large B-cell lymphoma (IVLBCL) associated with hemophagocytic syndrome, disseminated intravascular coagulopathy, and lung involvement. G-banding analysis of the metaphase spreads obtained from the bone marrow showed that the lymphoma cells were near-tetraploid and included two homologues of the 14q+ chromosome. Spectral karyotyping revealed that complex translocations occurred among chromosomes 3, 12, 14, and 19, and additional materials of 14q+ were from chromosome 19 with the breakpoint at 14q32 and 19q13. To the best of our knowledge, this is the first report describing t(14;19)(q32;q13) in IVLBCL.     

Double-hit lymphoma with t(8;14)(q24;q32) and t(12;14)(q24;q32) chromosomal translocations

A 50-year-old man presented with an ileocecal tumor and a large amount of ascites. Lymphoma cells obtained from the ascitic fluid were CD10(+), CD20(+), CD38(+), HLA-DR(+), BCL6(-), MUM1/IRF4(+), BCL2(+), and immunoglobulin μ/γ(+). The karyotype determined by G-banding and spectral karyotyping was 46, XY, der(3)t(1;3)(q12;p12), -4, +7, t(8;14)(q24;q32), t(12;14)(q24;q32), der(17)t(4;17)(q21;p11). Fluorescence in situ hybridization disclosed that 93% of interphase cells were positive for the c-MYC and immunoglobulin heavy chain gene fusion. The patient was treated with intensive chemo-immunotherapy, resulting in a complete response. The t(8;14)-t(12;14) double-hit may have generated molecular abnormalities analogous to those of a previously cloned three-way translocation t(8;12;14).     

Translocation t(9;14)(p13;q32) in cases of splenic marginal zone lymphoma

Translocation t(9;14)(p13;q32) involving PAX5 and IGH genes was first described in lymphoplasmacytic lymphoma. New data suggest that this translocation is not restricted to a specific morphologic subtype but occurs in other B-cell lymphomas. We present three cases with a diagnosis of splenic marginal zone lymphoma and t(9;14) confirmed by fluorescent in situ hybridization.     

Analysis of 2 men with t(8;22)(q13;q13) and t(8;14)(q13;q22) chromosomal translocation karyotypes

Male infertility is a multifactorial condition that is closely associated with chromosomal abnormalities. Reciprocal chromosomal translocation (RCT) is a significant structural genetic abnormality. The specific mechanisms of forms of RCT affecting male infertility include the product of chromosomally unbalanced gametes, thereby disrupting the structure and function of important genes responsible for spermatogenesis. RCT breakpoints have been found to disrupt gene structure and function in many medical fields However, the relationship between RCT breakpoints and male infertility remains to be determined. The purpose of this study is to describe 2 male carriers of RCTs 46,XY,t(8;22)(q13;q13) and 46,XY,t(8;14)(q13;q22). Both patients were collected from the second hospital of Jilin University. Semen parameters were detected using the computer-aided semen analysis system. Cytogenetic analysis was performed using standard operating procedure. Related genes on chromosomal breakpoints were searched using Online Mendelian Inheritance in Man. One man had semen parameters within the normal range, but the couple was infertile after 5 years of marriage. The other man showed normal semen parameters, and his wife had experienced 2 spontaneous miscarriages. Using a literature search, the association between chromosome 22q13 breakpoint and fertility were investigated. The results suggest that physicians should focus on the clinical phenotype of the patients and the breakpoints of RCT in genetic counseling. An important gene related to human male infertility is clearly located in chromosome region 22q13, and its function is worthy of further study.     

The ultrastructure of mantle cell lymphoma and other B-cell disorders with translocation t(11;14)(q13;q32)

We conducted an ultrastructural study in 22 cases of B-lymphoproliferative disorders in leukaemic phase bearing the t(11;14) translocation. The features of peripheral blood leukaemic cells in nine cases of mantle cell lymphoma (MCL) were compared to those diagnosed as B-prolymphocytic leukaemia (B-PLL) (five cases), splenic lymphoma with villous lymphocytes (SLVL) (four cases), lymphoplasmocytic lymphoma (LPL) (one case), chronic lymphocytic leukaemia with >10% prolymphocytes (CLL/PL) (one case) and unclassified B-non Hodgkin's lymphoma (B-NHL) (two cases). The ultrastructural characteristics were also compared to those present in B-NHL without t(11;14), including cases of follicular centre lymphoma (FCL). This study shows that MCL has distinct ultrastructural features including a cleaved or indented nucleus with an even heterochromatin distribution, an absent or inconspicuous nucleolus, low N/C ratio, abundant mitochondria, a well developed Golgi zone, profiles of endoplasmic reticulum and centrioles. This pattern clearly differs from that found in FCL cells. The nuclear pattern of MCL cells also differed from the cells in the other disorders with t(11;14), but shared an organelle-rich cytoplasm, and features which were not apparent in cases without t(11;14). The cytoplasmic changes observed in cells bearing t(11;14) suggest increased cellular activity which may relate to the chromosome translocation and the resulting over-expression of bcl-1.     

t(9;14)(p13;q32) denotes a subset of low-grade non-Hodgkin's lymphoma with plasmacytoid differentiation.

In this series of 426 consecutively ascertained, karyotypically abnormal non-Hodgkin's lymphomas (NHLs) derived from 407 patients, a t(9;14)(p13;q32) was encountered in 7 cases; an additional case demonstrated t(9;14)(p1?3;q32). At the time of detection of t(9;14), four cases were small lymphocytic lymphomas with plasmacytoid features; in three of these the t(9;14) was the sole karyotypic abnormality. In two cases of large-cell NHL demonstrating t(9;14), retrospective review of prior lymph node biopsies showed the presence of a small lymphocytic lymphoma of the plasmacytoid subtype. The remaining two cases comprised a large-cell lymphoma of the brain and a follicular NHL. Thus, six of eight cases (75%) had an initial identical low-grade histology. Immunohistochemical analysis of six cases showed no reactivity with CD1, CD2, CD4, CD5, CD8, and CD10 and high reactivity with CD19 and CD20. All four lymphocytic lymphomas and one of the two large-cell NHLs showed cytoplasmic Ig, consistent with plasmacytoid differentiation. Of the eight cases in this series, six presented with or developed stage IV disease; all were characterized by a 6-month to 5-year clinical phase of indolent disease before treatment was instituted. All five patients with low-grade NHL at the time of cytogenetic analysis were alive with recurrent disease at 3-year median follow-up. The remaining three patients with large-cell diffuse histologies relapsed after intensive therapy and expired at a median of 3 years from diagnosis; two of these showed previous or metachronous small lymphocytic tumors. These results suggest a novel biologically distinct subset of NHL; a neoplasm of mature B lymphocytes with plasmacytoid differentiation, characterized by t(9;14); and an indolent presentation followed by gradual clinical progression of disease.     

Characterization of a new non-Hodgkin's lymphoma cell line (NCEB-1) with a chromosomal (11:14) translocation [t(11:14)(q13;q32)]

A new cell line, NCEB-1, was established by Epstein-Barr virus (EBV) transformation of peripheral blood mononuclear cells from a patient with centroblastic-centrocytic diffuse lymphoma expressing IgM lambda. The transformed cells were lymphoblastoid, with many cells showing a plasmacytoid morphology. The NCEB-1 cells had cytoplasmic Ig (CyIg), with loss of the surface Ig (SIg) expression. Cytogenetic analysis of the cell line demonstrated two clones with variations: a hypodiploid clone, with a complex karyotype including a t(11;14)(q13;q32) similar to the original tumor cells, and a near tetraploid clone with the same markers. Southern blot analysis of DNA from the patient's neoplastic cells and NCEB-1 demonstrated identical Ig heavy chain gene rearrangement, confirming the origin of the cell line. The cell line was not tumorigenic when tested in an in vitro assay using immunosuppressed mice. NCEB-1 has been in continuous culture for 9 months and will be valuable for the in vivo study of non-Hodgkin's lymphoma and EBV transformation.     

Primary splenic lymphoma with t(3;14)(q27;q32) chromosomal abnormality and rearrangement of BCL-6 gene]

Primary splenic lymphoma (PSL) is extremely rare, accounting for less than 1% of all reported cases of extranodal lymphoma. A 62-year-old woman was referred to our hospital because of general fatigue. A heterogenous mass with irregular margins was detected in the spleen by abdominal computed tomographic scan, and Gallium scintigraphy demonstrated abnormal accumulation only in the spleen. Malignant lymphoma was strongly suspected on the basis of histologic findings from an ultrasonically guided needle biopsy. The final diagnosis was established by splenectomy as PSL of diffuse large B-cell type. After 6 courses of CHOP chemotherapy, the patient recovered and has been disease-free more than a year. Chromosomal analysis of her tumor cells detected t(3;14)(q27;q32), an abnormality not reported in cases of PSL to date. The rearrangement of BCL-6 was also observed. We discuss the possibility of BCL-6 involvement in Japanese cases of PSL, with reference to case reports dating back over the past decade.     

Multiple myeloma and the translocation t(11;14)(q13;q32): a report on 13 cases

Complex cytogenetic abnormalities have been described in patients with multiple myeloma (MM). To better understand the significance of the most frequent translocation observed in MM, we studied the clinical characteristics of patients with MM and the t(11;14)(q13;q32) abnormality. A search of the cytogenetic database at the Mayo Clinic identified patients with MM and t(11;14)(q13;q32). The medical records were reviewed for the clinical characteristics of these patients. We identified 13 patients with MM and t(11;14)(q13;q32) determined by standard cytogenetic analysis; in 10 patients the abnormality was detected at the time of relapse (three with previously normal results of cytogenetic examination). At the time the translocation was detected, plasma cell (PC) leukaemia was clinically diagnosed in two patients. The median number of circulating PCs, as determined by the cytoplasmic immunofluorescence of T-cell-depleted peripheral blood mononuclear cells, was 1.1 × 10⁹/l (mean 1.74; range 0.0017–6.26 × 10⁹/l). On linear regression analysis there was a strong correlation between the number of circulating PCs and the number of bone marrow PCs. The median survival after demonstration of the translocation was 8.1 months. Of all patients, 10 died of disease progression and three were alive. Patients with MM who have t(11;14)(q13;q32) seem to have an aggressive clinical course, even when the abnormality is detected at the time of diagnosis, with evidence of many circulating PCs.     

Clinical implications of t(11;14)(q13;q32), t(4;14)(p16.3;q32), and -17p13 in myeloma patients treated with high-dose therapy

Fluorescence in situ hybridization (FISH) is more sensitive than conventional cytogenetics for recognizing chromosomal changes. Several FISH-detected abnormalities have been associated with inferior prognosis, including deletion of chromosomes 17 and 13 (Delta13) and t(4;14)(p16.3;q32). We analyzed the prognostic value of FISH testing in 238 patients who received high-dose therapy between January 1990 and September 2001. All patients had pretransplantation cytoplasmic immunoglobulin FISH done on cytospin slides from bone marrow aspirates for t(11;14), t(4;14), and -17(p13.1) (TP53). Time to progression and overall survival were significantly shorter for patients with t(4;14) and those with -17(p13.1) but were not affected by t(11;14). Overall survival was significantly shorter for patients with both t(4;14) and Delta13 abnormalities than for those with Delta13 alone (26.8 vs 18.8 months). In a multivariable analysis of the effect of Delta13 and t(4;14), the risk ratio for t(4;14) was greater than for Delta13 (2.6 vs 1.5). For high-dose therapy patients, -17(p13) and t(4;14) have clinical importance for estimating time to progression and overall survival. The presence of t(4;14) identifies a subset of patients whose time to progression is only 8.2 months. These patients receive minimal benefit from autologous stem cell transplantation and are candidates for novel therapeutic approaches.     

Large variation in t(11;14)(q13;q32) and t(14;18)(q32;q21) translocation product size is confirmed by sequence analysis of PCR products

Polymerase chain reaction is commonly used to detect t(11;14)(q13;q32) and t(14;18)(q32;q21) chromosomal translocations associated with mantle cell lymphoma and follicular lymphoma. We tested a total of 482 samples from patients with suspected non-Hodgkin's lymphoma and sequenced unusual-sized t(11;14)(q13;q32) and t(14;18)(q32;q21) products from 33 of these patients. BCL-1 or BCL-2 gene rearrangements were confirmed in 23 of 33 patients (70%). Considerable size variation was observed using t(11;14) primers, with MTCA and MTCB t(11;14) products ranging from 234 to 934 bp and 143 to 560 bp respectively. Less variability was observed for t(14;18) Major Breakpoint Region (MBR) products (100-252 bp) but Minor Cluster Region (MCR) products ranged from 217 to 498 bp. We demonstrate the utility of sequence analysis to confirm unusual-sized translocation products and reduce false-positive results because of nonspecific amplification.     

Immune pancytopenia associated with a leukemic B-cell tumor carrying t(14;18)(q32;q21) translocation

We report a 75-year-old man who was initially suggested to have acute leukemia. The hemoglobin level was 3.8 g/dL, white cell count was 7,700/μL with an absence of mature neutrophils and 69.0% leukemic cells, and platelet was 0.4 × 10(4)/μL. Coombs' antiglobulin test was positive. Leukemic cells were CD5(-), CD10(+), CD20(+), CD23(-), and IgG/λ(dim+). The bone marrow consisted of normal hematopoietic precursors, whereas fluorescence in situ hybridization detected the BCL2/IgH fusion gene. He was treated with rituximab-containing chemotherapy, resulting in the resolution of pancytopenia. The underlying disease was a leukemic B-cell tumor with t(14;18)(q32;q21), and the pancytopenia was mainly caused by autoimmune mechanisms.     

TEL gene is involved in myelodysplastic syndromes with either the typical t(5;12)(q33;p13) translocation or its variant t(10;12)(q24;p13)

A t(5;12)(q33;p13) translocation is a recurrent chromosome abnormality in a subgroup of myeloid malignancies with features of both myeloproliferative disorders and myelodysplastic syndromes (MDSs). The molecular consequence of a t(5;12) is a fusion between the platelet- derived growth factor receptor-B gene on chromosome 5 and a novel ETS- like gene, TEL, on chromosome 12. We report on three patients with a t(5;12)(q33;p13) diagnosed as chronic myelomonocytic leukemia, and one case of a t(10;12)(q24;p13) in a progressive MDS, with eosinophilia and monocytosis. Involvement of the TEL gene in these chromosome translocations was investigated by fluorescence in situ hybridization (FISH) with cosmid probes containing selectively the 5' end or 3' end of TEL. Hybridization of these cosmids to the der(5)/der(10) or a der(12), respectively, demonstrated a rearrangement of TEL in both translocations, showing that the t(10;12) is a variant translocation of the t(5;12). Cloning of the fusion cDNA of one case of t(5;12) showed that the breakpoint occurred at the RNA level at exactly the same position as reported by Golub et al (Cell 77:307, 1994). In addition, the TEL gene on chromosome 12 could be localized between two probes previously mapped to 12p13, namely PRB1 and D12S178, leading to a better definition of the position of TEL in this chromosome region. Moreover, in the case involving chromosome 10, the breakpoint occurred between cKTN206 and cKTN312/LYT-10 at 10q24. Clinicohematological data in these studies as well as the restriction mapping of chromosomal breakpoints strongly suggest that (1) common features in MDSs involving the TEL gene are monocytosis and eosinophilia, (2) chromosomes other than no. 5 may be involved and at least a t(10;12)(q24;p13) variant chromosome translocation does exist in these MDSs, and (3) both standard and variant 12p/TEL translocations may be identified by FISH with appropriate probes.     

Diffuse large B-cell lymphoma carrying both t(3 ; 7)(q27 ; p12) and t(8 ; 14)(q24 ; q32)

We report a 60-year-old man with diffuse large B-cell lymphoma harboring both t(3 ; 7)(q27 ; p12) and t(8 ; 14)(q24 ; q32). Although he received six courses of conventional combination chemotherapy plus rituximab, early relapse occurred. Four courses of an intensive salvage regimen and high-dose chemotherapy with autologous peripheral blood stem cell transplantation were performed. The patient has remained in complete remission for over 24 months. This case is noteworthy because both genetic abnormalities are implicated in lymphomagenesis.     

An additional breakpoint region in the BCL-1 locus associated with the t(11;14)(q13;q32) translocation of B-lymphocytic malignancy

The t(11;14)(q13;q32) translocation is associated with human B- lymphocytic malignancy. This translocation divides the IgH locus on chromosome 14q32 and may activate a postulated proto-oncogene, bcl-1, located on chromosome 11q13. Two samples of chronic lymphocytic leukemia with the t(11;14)(q32;q13) translocation were studied. The break in one sample was shown to join Jh sequences with the previously described bcl-1 major translocation cluster. DNA blots of the second sample suggested that Jh sequences were joined to a different breakpoint region on chromosome 11. This translocation was cloned and found to link the human Jh3 region and a new breakpoint region 63 kb telomeric of the major translocation cluster. This translocation occurred in part as the result of an aberrant D-J recombination. Recurrent translocations human B-lymphocytic malignancy. The definition of a new breakpoint region may aid the identification of the postulated bcl-1 gene.