Abnormalities In Lymphoma Research Articles

An Evaluation of Hemostatic Dysregulation in Canine Multicentric Lymphoma

Multiple hemostatic abnormalities are associated with paraneoplastic syndrome and some malignant tumors. Lymphoma is the most common hematopoietic neoplasm in dogs, sometimes associated with hemostatic changes. The objectives of this study were to evaluate the behavior of coagulation parameters in dogs with multicentric lymphoma compared with diseased dogs without lymphoma, to separately evaluate the effect of immunophenotype (B lymphoma versus T lymphoma) on the variables of interest as well as the effect of disease stage (stage II to IV versus stage V). Specifically, a cross-sectional study was performed with a matched comparison group considering 170 dogs with B or T lymphoma (group 1) and 170 dogs with no lymphoma or other neoplastic processes but other diseases (group 0). Eight coagulation parameters were evaluated: platelet count (Plt), activated partial thromboplastin time (aPTT), prothrombin time (PT), thrombin time (TT), fibrinogen, fibrin/products of fibrinogen degradation (FDPs), fibrin D-dimers, and antithrombin (AT). Dogs with lymphoma showed prolonged PT and TT, decreased fibrinogen, increased FDP, and decreased Plt compared with group 0. The effect of disease stage was evaluated separately for dogs with stage II to IV lymphoma and dogs with stage V lymphoma; patients with stage II–IV lymphoma showed no significant differences, while in dogs with stage V lymphoma, a prolongation of PT and TT, a decrease in fibrinogen, an increase in FDPs and a decrease in Plt were found compared with the group 0. Finally, the comparison between B lymphoma and T lymphoma showed no significant differences in coagulation parameters between the two groups. Logistic regression analysis demonstrated that low fibrinogen and platelet levels were the most significant predictors of lymphoma in a cohort of canine patients. These hemostatic abnormalities in lymphoma appeared to be associated with the stage of the disease rather than the lymphoma immunophenotype. These findings pave the way for the possible scenario of lymphoma-associated fibrinolysis and the so far undescribed pattern of hyperfibrinolysis associated with the most severe stage of lymphoma.

Study of Molecular Cytogenetic Abnormalities in Lymphoma and Their Clinical Relevance

Objective: To investigate the issue of molecular cytogenetic abnormalities in lymphoma and to study their clinical relevance. Methods: First, medium-term chromosomes of healthy men and women were prepared. Normal human peripheral blood lymphocytes were stimulated with PHA, treated with MTX synchronization, blocked with colchicine, cultured for 3 days, routinely treated with hypotonicity, cells were obtained, and steam-dried method was used to drop slices for backup. Next, comparative genomic hybridization. Preparation of probes; processing of normal human mid-term split images; hybridization; washing of slices after hybridization; staining; fluorescence microscopy observation, uptake and analysis of fluorescence signals. Results: Lymphoma CGH test results; Relationship between CGH abnormalities and lymphoma histological subtypes:Hodgkin's lymphoma CGH abnormalities, diffuse large B-cell lymphoma (DLBCL) CGH abnormalities, follicular lymphoma (FL) CGH abnormalities, and follicular lymphoma (FL) CGH abnormalities; Correlation between CGH test results and lymphoma clinical features: CGH test results and lymphoma patients, the type of CGH abnormality correlated with the clinical features of lymphoma, simple CGH abnormalities and complex CGH abnormalities correlated with the clinical features of lymphoma patients, and CGH abnormalities at specific chromosomal sites correlated with the clinical features of lymphoma. Conclusion:Conventional model analysis examines both chromosomal translocations and gene deletions or spreads, fails to observe the full picture of the lymphoma genome, and fails to detect new chromosomal abnormalities.

Imaging of primary pediatric lymphoma of bone.

Primary pediatric bone lymphoma is a rare form of non-Hodgkin lymphoma. Unlike nodal forms of lymphoma, imaging abnormalities in lymphoma of bone do not resolve rapidly in conjunction with treatment and radiologic findings can remain abnormal for years, making it difficult to evaluate treatment response. To evaluate the utility of imaging in assessment of patients with primary pediatric bone lymphoma. At our institution between 2004 and 2013, six cases of pathology-proven primary pediatric bone lymphoma were diagnosed. Retrospective chart review was performed to assess imaging utilization. Our data were qualitatively compared with existing literature to construct an algorithm for imaging patients with primary lymphoma of bone. Imaging evaluation of patients with primary pediatric bone lymphoma was highly variable at our institution. Conventional imaging was routinely used to evaluate response to treatment, despite lack of appreciable osseous change. Imaging in the absence of symptoms did not alter clinical management. Only positron emission tomography CT (PET/CT) proved capable of demonstrating imaging changes from the pretreatment to the post-treatment scans that were consistent with the clinical response to treatment. Surveillance imaging is likely unnecessary in patients with a known diagnosis of pediatric lymphoma of bone. Pretreatment and post-treatment PET/CT is likely sufficient to assess response. There is little data to support the use of interim and surveillance PET/CT.

FOXP1 abnormalities in lymphoma: translocation breakpoint mapping reveals insights into deregulated transcriptional control

Deregulation of FOXP1 expression plays an important role in lymphoma development although the underlying molecular mechanism is poorly understood. FOXP1 is targeted by chromosome translocations in MALT lymphoma and diffuse large B-cell lymphoma, where high-level protein expression is associated with poor prognosis. Nonetheless, the incidence and nature of FOXP1 abnormalities at both the genetic and protein levels, and their correlation in these lymphomas are not well established. We investigated FOXP1 translocation, copy number change and protein expression in MALT lymphoma (n=321), MALT lymphoma with a diffuse large B-cell lymphoma component (59), nodal diffuse large B-cell lymphoma (64) and extranodal diffuse large B-cell lymphoma (151) by interphase fluorescence in situ hybridization and immunohistochemistry. FOXP1 translocation was found in eight MALT lymphomas and three MALT lymphomas with diffuse large B-cell lymphoma, with all positive cases originating in the stomach. In diffuse large B-cell lymphoma, the translocation was seen in 5 cases originating in the stomach (2), tonsil (1), large intestine (1) and lymph node (1). Immunoglobulin heavy chain gene was the translocation partner in 11 of the 16 positive cases. Fluorescence in situ hybridization mapping revealed FOXP1 breakpoints within the 5′ untranslated region of the gene (upstream of exon 6, the first coding exon of full-length FOXP1) in 14 cases, but downstream of exon 6 (most likely upstream of exon 8) in the remaining 2 cases. Three copies of the FOXP1 gene were observed in MALT lymphoma (17%), MALT lymphoma with diffuse large B-cell lymphoma (12%) and diffuse large B-cell lymphoma (32%), including cases with FOXP1 translocation (19%). Immunohistochemistry showed strong/moderate FOXP1 staining in all the cases with FOXP1 translocation. However, FOXP1 expression was independent of FOXP1 translocation or copy number changes. Our findings suggest that (1) FOXP1 translocation may disrupt the full-length FOXP1 transcript and lead to expression of FOXP1 transcript variants with alternate 5′ ends and (2) mechanisms other than translocation and copy number changes are also responsible for FOXP1 overexpression in lymphoma.

Lymphoma Associated Chromosomal Abnormalities Can Be Easily Detected by FISH on Tissue Imprints. an Underused Diagnostic Alternative.

Detection of specific chromosomal abnormalities is essential in the diagnosis of several lympholiferative disorders. However, conventional cytogenetic studies are not frequently carried out from biopsies as it is in bone marrow (BM) specimens. On the contrary, FISH is usually performed on paraffin embedded tissue, an alternative with potential technical nuances both in its application and its interpretation. In our experience, FISH on tissue imprints is the ideal alternative to overcome these problems. In the present study, 46 tissue imprints and 17 BM smears from 43 patients with lymphomas were selected to investigate the presence of t(14;18)(q32;q21), t(11;14)(q13;q32), t(8;14)(q24;q32) and t(3;var)(q27;var). Representativity of the samples was assured prior to FISH by rapid May-Grümwald staining (Diff-Quick, QCA, Spain). Twenty imprints from reactive palatine tonsils and adenoids were used as negative controls. FISH was performed with specific dual-color dual-fusion FISH (D-FISH) probes for the first 3 translocations and a dual-color break-apart FISH probe for t(3;var)(q27;var) following the instructions of the probes supplier (Vysis, Inc). All except one sample (a BM smear stored at room temperature over 9 years), rendered satisfactory FISH hybridizations. In any case, all 43 patients could be successfully studied by FISH (the case referred above in which FISH failed in a first attempt was successfully analyzed using a different sample). The results supported the suspected diagnosis of follicular lymphoma in 22 patients, mantle cell lymphoma in 12 patients, large B-cell lymphoma in 5 patients, marginal zone lymphoma in 2 patients and B chronic lymphocytic leukemia in 2 patients. In one case, the observation of t(11;14) by FISH allowed to reclassify the case from follicular to mantle cell lymphoma and also to demonstrate clonal evolution by studying sequential tissue imprints stored for more than 6 years. Negative results also aided in the assignment of patients to proper diagnostic categories. FISH performed on tissue imprints and BM smears constitutes an optimal strategy for retrospective and prospective investigation of chromosomal abnormalities in lymphomas. Tissue imprints and BM smears conventionally stored at room temperature even for long periods of time can be safely used and sent by ordinary mail without special considerations for this purpose. Based on our experience we recommend to perform and routinely store tissue imprints whenever fresh tissue is available.

MALT1 Is an Essential Regulator of Antigen Receptor Mediated NF-kappaB Activation.

The translocation t(11;18)(q21;q21) is the most common chromosomal abnormality in lymphomas of mucosa associated lymphoid tissue (MALT lymphoma). Molecular cloning of the breakpoint demonstrated that t(11;18) leads to the fusion of the IAP2 gene to the novel gene MALT1. MALT1 encodes a paracaspase that can bind to BCL10 but its cellular function was unknown. We have previously demonstrated that BCL10, which is involved in independent MALT lymphoma translocations, functions as a positive regulator of lymphocyte proliferation. BCL10 connects antigen receptor signaling in B and T cells to NF-kappa B activation. To identify the physiological role of MALT1 we have now disrupted the MALT1 gene in mice. Here we are using both MALT1 and BCL10 deficient animals and show that MALT1 is essential for functional T cell activation, proliferation and cytokine production in response to T cell receptor (TCR) ligation. Similar to BCL10 we found MALT1 to be strictly required for signal-specific NF-kappaB activation in response to TCR ligation but not for TNF-alpha or IL-1 signaling. MALT1 operates downstream of BCL10, controls the catalytic activity of IKK and additionally regulates signaling of p38 and JNK MAP kinases. Moreover we found MALT1 to be critical for B1 and marginal zone (MZ) B cell development. In contrast to BCL10 disruption however, inactivation of MALT1 has only mild effects on conventional B2 B cell activation, BCR induced NF-kappaB signaling in splenic B lymphocytes and does not cause defects during embryonic development. Thus, MALT1 is an essential regulator of BCL10 mediated NF-kB induction that is differentially required depending on the cellular context. Together these data support the view that normal expression of BCL10 and MALT1 are necessary for controlled NF-kB signaling in lymphocytes whereas deregulation of either BCL10 or MALT1 through chromosomal translocation results in increased lymphocyte growth and survival

Differential Requirement for Malt1 in T and B Cell Antigen Receptor Signaling

The translocation t(11;18)(q21;q21) involving MALT1 is the most common chromosomal abnormality in lymphomas of mucosa-associated lymphoid tissue. Although the paracaspase MALT1 can bind to BCL10, the physiological function of MALT1 is unknown. Using mouse models, we show that Malt1 is essential for T cell activation, proliferation, and IL-2 production in response to TCR ligation and strictly required for signal-specific NF-κB activation induced by the TCR but not TNF-α or IL-1 signaling. Malt1 operates downstream of Bcl10, controls the catalytic activity of the canonical IKK complex, and regulates the signaling of Jnk and p38 MAP kinases. In contrast to Bcl10 disruption, however, inactivation of Malt1 has only mild effects on B cell activation and does not cause defects during neurodevelopment. Thus, Malt1 is an essential regulator of Bcl10 signaling that is differentially required depending on cellular context.

Metabolic Abnormalities in Lymphoma

Metabolic abnormalities occur relatively frequently in lymphoma patients undergoing chemotherapy. These abnormalities include hyperuricemia, hypercalcemia, hyperphosphatemia, hypocalcemia, hypomagnesemia, hyponatremia, and hyperkalemia. In addition, tumor lysis syndrome can result in several metabolic abnormalities, leading to potential renal failure. If these syndromes are identified promptly, they can be corrected. Guidelines for identifying metabolic abnormalities in lymphoma patients, as well as management suggestions, are presented.

Strain-dependency of chromosomal abnormalities in lymphomas developed in E(mu)-myc transgenic mice.

We previously showed that B and T cell lymphoma development in Em (immunoglobulin heavy chain enhancer)-myc transgenic mice is dependent on the mouse strain. To determine whether any non-random chromosomal abnormality that was present was caused by variations in the lymphoma cell type or by a different genetic background, we crossed C3H transgenic mice with other inbred strains of mice, C57BL / 6 or BALB / c. Cytogenetic analysis showed a high frequency of non-random chromosomal aberrations, namely, duplication or amplification of part of chromosome 5 containing the transgene and trisomy of chromosome 1, 6, or 12 in the genetic background of C3H x C57BL / 6 mouse and C3H x BALB / c mouse, respectively, regardless of cell type of lymphoma. These results suggest that non-random chromosomal abnormalities in lymphoma cells are dependent on the genetic background of mouse, not on the tumor cell type in Em-myc transgenic mouse.

Strain-dependency of chromosomal abnormalities in lymphomas developed in E mu-myc transgenic mice.

We previously showed that B and T cell lymphoma development in Eμ (immunoglobulin heavy chain enhancer)‐mye transgenic mice is dependent on the mouse strain. To determine whether any non‐random chromosomal abnormality that was present was caused by variations in the lymphoma cell type or by a different genetic background, we crossed C3H transgenic mice with other inbred strains of mice, C57BL/6 or BALB/c. Cytogenetic analysis showed a high frequency of non‐random chromosomal aberrations, namely, duplication or amplification of part of chromosome 5 containing the transgene and trisomy of chromosome 1, 6, or 12 in the genetic background of C3HXC57BL/6 mouse and C3HxBALB/c mouse, respectively, regardless of cell type of lymphoma. These results suggest that non‐random chromosomal abnormalities in lymphoma cells are dependent on the genetic background of mouse, not on the tumor cell type in Eμ‐myc transgenic

Lack of Cytogenetic Abnormalities in Castlemanʼs Disease*

Castleman's disease (CD) is a distinctive type of atypical lymph node hyperplasia that is often clonal. In a previously reported series of CD, clonal populations of plasma cells were detected by immunohistology in 4 of 39 cases (10%, lambda restricted), and immunoglobulin gene rearrangements were detected by paraffin polymerase chain reaction (PCR) analysis in 10 of 37 cases (27%). Cytogenetic analysis has been used to detect clonal proliferations of plasma cells in myeloma and clonal proliferations of lymphocytes in lymphomas and has identified critical gene loci that are important in the histopathogenesis of these disorders. Cytogenetic studies have not been done on a large series of patients with CD. Thus, we reviewed the archives of our institution for cases of CD and lymphoma that had had cytogenetic analysis. The cytogenetic and lymphoma archives of our institution (a tertiary care center) from 1985 to 1998 were reviewed for the diagnoses of CD and lymphoma. There were 21,006 lymphomas, 701 of which had cytogenetic analysis (400 abnormal). There were 162 cases of CD, 7 of which had cytogenetic analysis. The frequency of cytogenetic abnormalities in CD was compared with that in lymphoma. The sensitivity of cytogenetics for defining clonality in CD was compared with immunohistology and paraffin PCR-amplified immunoglobulin heavy-chain gene rearrangement. From 1985 to 1998, 162 cases of CD and 21,006 cases of lymphoma were diagnosed. Cytogenetic analysis yielded adequate numbers of metaphases for analysis of 4 cases of CD and 701 lymphomas. Cytogenetic abnormalities were not identified in CD but were identified in 400 lymphomas (57%). Although 1 of 4 cases of CD was clonal by immunohistology (lambda restricted), no immunoglobulin gene rearrangements were detected by paraffin PCR analysis. The frequency of cytogenetic abnormalities in lymphomas and the lack of cytogenetic abnormalities in CD suggest that cytogenetic abnormalities, as detected by conventional cytogenetic analysis, are important in the pathogenesis of lymphoma but not CD. The lack of cytogenetic abnormalities in CD supports the hypothesis that CD is an interleukin-6-driven lymphoproliferative disorder.

Update on lymphoma pathology III: lymphoma classification and nodal lymphomas

Lymphoma classification has for years been confusing and at times exasperating, based solely on haematoxylin-and eosin-stained histological sections. Several major advances have allowed a new and less subjective classification to be developed:
 • use of immunostains
 • recognition that extranodal lymphomas are special
 • discovery of specific cytogenetic abnormalities in lymphomas
 • better understanding of lymphocyte physiology

Chromosomal abnormalities in lymphoma and their correlations with nucleic acid flow cytometry

Cytogenetic studies were performed on 25 samples obtained from 25 patients with lymphoma. Fourteen of these were also simultaneously studied with nucleic acid flow cytometry to determine percent S-phase and DNA content (ploidy). In 17 cases (68%), evaluable metaphases were obtained. The evaluable metaphase rate was higher in previously untreated patients ( 15 19 or 79%). All but two cases showed abnormal karyotype. All five cases showing either the t(8;14) or t(8;22) abnormality were associated with extremely high percent S-phase values, ranging from 36% to 47%, which is in the range of high-grade lymphomas according to our previous experience. Four of these cases were diagnosed as Burkitt's lymphoma and one as diffuse large cell lymphoma. Further review of this latter case resulted in the pathologic diagnosis being changed to Burkitt's lymphoma. Three patients had either numerical or structural abnormalities of chromosome #21 [two cases of extra chromosomes and one i(21q)]. All three cases were diagnosed as diffuse large cell lymphoma. Four instances of trisomy 12 were identified. Only one of these was diagnosed as diffuse well-differentiated lymphocytic lymphoma. The remaining three were Burkitt's lymphoma in two and diffuse large cell lymphoma in one. Two instances of t(14;18) were observed. This is the characteristic abnormality of follicular lymphomas. One of these cases was a follicular large cell lymphoma. The second case had possibly originated from a follicular mixed lymphoma and had evolved into a diffuse mixed cell type. Both of these cases had low S-phase values in the range of low-grade lymphomas. The correlation between ploidy as determined by flow cytometry and cytogenetic analysis was good whenever the DNA index was elevated. However, when the DNA index was 1.0 (diploid), concordant measurements were observed in only five of eight cases. Flow cytometry detected one instance of clearly abnormal ploidy, which was thought to be diploid by cytogenetics. This case most likely represents a “false negative” cytogenetic determination.

Karyotype peculiarities of malignant lymphomas

Karyotypes of 30 malignant lymphomas were studied with the aid of G-banding. Frequent occurrence of rearranged chromosomes 14 and 11 was noted. In several tumors, identical acrocentric markers, appearing after translocation of the long arm of chromosome 11 on the long arm of chromosome 14, were revealed. Other common karyotype abnormalities in lymphomas were trisomy 3 and trisomy 18. The chromosomes preferentially involved in karyotype abnormalities of the malignant lymphomas are mostly not altered in other hemoblastoses.

CHROMOSOMAL ABNORMALITIES IN LYMPHOMA.

CHROMOSOMAL ABNORMALITIES IN LYMPHOMA.