Molecular Mechanism and Malignant Clonal Evolution of Multiple Myeloma / 中国实验血液学杂志

Almost all patients with multiple myeloma (MM) have chromosomal translocation which can result in genetic variation. There are mainly five types of chromosomal translocations, involving the IGH gene translocation to 11q13 (CCND1), 4p16 (FGFR/MMSET), 16q23 (MAF), 6p21 (CCND3) and 20q11 (MAFB). It is possible that all IGH translocations converge on a common cell cycle signal pathway. Some MM develops through a multistep transformation from monoclonal gammopathy of undetermined significance (MGUS) to smoldering MM (SMM) and eventually to MM and plasma cell leukemia (PCL). Similarly to what Darwin proposed in the mid-19th century-random genetic variation and natural selection in the context of limited resources, MM clonal evolution follow branching and nonlinear mode. The failure of MM treatment is usually related with the minimal subclone which is hardly found at newlydiagnosed.

Correlation of immunoglobulin variable heavy chain gene mutation status with prognosis in patients with mantle cell lymphoma / 中华病理学杂志

<p><b>OBJECTIVE</b>To study the relationship between immunoglobulin variable heavy chain (IgVH) gene mutation status and clinical features, pathologic findings and biologic behavior of mantle cell lymphoma (MCL).</p><p><b>METHODS</b>IgVH gene was amplified in 60 cases of MCL with FR1-JH and FR2-JH primers in BIOMED-2. The sequence was determined by cloning. The IgVH somatic mutational status was analyzed using NCBI's Ig-Blast tool. The relationship between IgVH gene mutation status and clinicopathologic features was also analyzed.</p><p><b>RESULTS</b>Forty percent (24 cases, 28 functional Ig genes) of the MCL cases displayed somatically mutated VH genes (defined as > 2% mutated), whereas 60.0% (36 cases, 40 functional Ig genes) showed unmutated VH genes. The most widely used genes were VH3-21 (27.9%) and VH4-34 (19.1%). The former were mainly used by unmutated cases, while the later mainly by mutated cases.Intraclonal heterogeneity was noted in 19 cases. There was no correlation of VH mutation status and specific VH gene with survival (P > 0.05).</p><p><b>CONCLUSIONS</b>MCL comprises at least two subsets that do not correlate with morphology: one with unmutated VH genes and one with mutated VH genes. The biased use of VH3-21 and VH4-34 is noted. The nonrandom usage of IgVH segments suggests specific antigens may play a role in the pathogenesis and progression of MCL subsets. There is no correlation of IgVH mutation status and specific VH gene with survival.</p>

Immunoglobulin heavy chain gene rearrangement in non B-cell haematological malignancies / Reordenamiento del gen de la cadena pesada de inmunoglobulina en las neoplasias hematológicas de linfocitos no B

PURPOSE: Clonality detection through amplifying immunoglobulin heavy chain (IGH) gene rearrangements by polymerase chain reaction (PCR) is a useful tool in diagnosis of various B-lymphoid malignancies. Immunoglobulin heavy chain gene rearrangement can be an optimal target for clonality detection in B-lymphoid malignancies. In the present study, we evaluated the presence of IGH gene rearrangement in non B-cell haemato-oncologypatients including T-cell acute lymphoblastic leukaemia (T-ALL), acute myeloblastic leukaemia (AML) and biphenotypic leukaemia. METHODS: We studied 18 cases of haematological malignancies which comprised five patients with TALL, 12 patients with AML and one with biphenotypic leukaemia. RESULTS: We found that the incidence of IGH gene rearrangement in T-ALL and AML were three (60%) and two (16.7%), respectively. The patient with biphenotypic leukaemia was negative for IGH gene rearrangement. CONCLUSION: Immunoglobulin gene rearrangement, which occurs in almost all haematological malignancies of B-cell lineage, also presents in a very small proportion of T-cell or myeloid malignancies.

OBJETIVO: La detección de la clonalidad mediante amplificación de los reordenamientos del gen de la cadena pesada (IGH) de inmunoglobulina por reacción en cadena de la polimerasa (RCP) es una herramienta útil en el diagnóstico de varios tumores malignos linfoides de células B. El reordenamiento del gen de la cadena pesada de inmunoglobulina puede ser un objetivo óptimo de la detección de la clonalidad en tumores malignos linfoides de células B. En el presente estudio, se evaluó la presencia de reordenamiento del gen IGH en pacientes de hemato-oncología de células no B, incluyendo la leucemia linfoblástica aguda de células T (LLA-T), leucemia mieloblástica aguda (LMA), y leucemia bifenotípica. MÉTODOS: Se estudiaron 18 casos de neoplasias malignas hematológicas que abarcaron cinco pacientes con (LLA-T), 12pacientes con AML y uno con leucemia bifenotípica. CONCLUSIÓN: Reordenamiento del gen de la inmunoglobulina que ocurre en casi todas las neoplasias malignas hematológicas del linaje de las células B, también se presenta en una proporción muy pequeña de células T o las neoplasias mieloides.

Immunophenotypes and prognosis of diffuse large B-cell lymphoma: a study of 500 cases / 中华病理学杂志

<p><b>OBJECTIVE</b>To study the immunophenotype and overall survival of diffuse large B-cell lymphoma (DLBCL) classified according to the 2008 World Health Organization classification of tumors of hematopoietic and lymphoid tissues.</p><p><b>METHODS</b>Five hundred cases of DLBCL were retrospectively analyzed with histologic review, immunohistochemistry, gene rearrangement study, in situ hybridization and fluorescence in situ hybridization. Follow-up data were collected. The overall survival rates of germinal center B-cell (GCB) and non-germinal center B-cell (non-GCB) subtypes, as well as those of DLBCL, not otherwise specified (NOS) and Epstein-Barr virus (EBV)-positive DLBCL of the elderly, were compared.</p><p><b>RESULTS</b>DLBCL-NOS was the commonest subtype which accounted for 77.2% (386/500) of the cases. EBV-positive DLBCL of the elderly, primary DLBCL of central nervous system, primary mediastinal (thymic) large B-cell lymphoma and T cell/histiocyte-rich large B-cell lymphoma accounted for 9.4% (47/500), 4.4% (22/500), 2.8% (14/500) and 2.6% (13/500), respectively. 68.5% (219/320) of DLBCL-NOS belonged to non-GCB subtype. The percentage of GCB subtype and CD5-positive subtype were 28.4% (91/320) and 3.1% (10/320), respectively. Comparison of the overall survival, GCB and non-GCB immunophenotypic groups have no significant difference (P = 0.93). And the same result in which of the EBV-positive DLBCL of the elderly and DLBCL-NOS group, before and after age matched (P = 0.13 and 0.28, respectively). A double-hit lymphoma was found by FISH detection, which presenting as gray zone lymphoma in morphology.</p><p><b>CONCLUSIONS</b>By using Hans algorithm, GCB and non-GCB subtypes show no significant difference in overall survival. EBV-positive DLBCL of the elderly and DLBCL-NOS also do not have significant difference in overall survival. Fluorescence in situ hybridization technique is helpful in identification of DLBCL with rare phenotypes.</p>

Detection of bcl-2/IgH fusion gene in lymphoma by real-time polymerase chain reaction and its clinical significance / 中国实验血液学杂志

The aim of this study was to investigate the bcl-2/IgH expression levels in patients with follicular lymphoma (FL) and diffuse large B-cell lymphoma (DLBCL) and its clinical significance. The bcl-2/IgH expression levels in bone marrow (BM) and/or peripheral blood (PB) of 20 patients were detected by using SYBR Green I real-time polymerase chain reaction, and the dynamic monitoring for bcl-2/IgH expression level in 4 of these patients was performed. The results showed that in patients with bcl-2/IgH-positive there was no statistically significant difference in the relative copy-numbers of bcl-2/IgH fusion gene in BM and PB (4.23 and 2.73 respectively, p = 0.107), but the difference was significant before and after treatment (3.61 and 2.69 respectively, p = 0.000), the expression level of bcl-2/IgH fusion gene in newly diagnosed and relapsed group was remarkably higher than that in remission group (p = 0.008). The bcl-2/IgH expression level in PB increased evidently 3 months prior to the clinical relapse in one case out of dynamically monitored 4 cases. It is concluded that the bcl-2/IgH expression level is associated with the disease status, the expression level is high in newly diagnosed and relapsed patients and low in those who achieved remission, the bcl-2/IgH fusion gene expression level decreased evidently after therapy, this change may be related to the clinical disease progression, the results suggest that peripheral blood can be regarded as the resource for detection of bcl-2/IgH fusion gene.

Generation of cytotoxic T lymphocytes specific for B-cell acute lymphoblastic leukemia family-shared peptides derived from immunoglobulin heavy chain framework region / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Immunoglobulin heavy chain variable region (IgHV) is a well-characterized tumor antigen for B-cell malignancies. It can function as a target for T cell-mediated immune response. Clinical trials of IgHV protein vaccines against lymphoma have demonstrated induction of tumor-specific cytotoxic T lymphocyte (CTL) responses. However, complementary determining regions-based individual vaccines have disadvantages for wide clinical application. Although a recent study demonstrated that immunogenic peptides are derived from framework regions (FR) shared among patients with B-cell lymphoma, how to choose the appropriate peptides for each patient is still unsolved. The aim of this study was to investigate whether immunoglobulin heavy chain FR-derived peptides shared in each IgHV family are potential CTL epitopes presented by B-cell acute lymphoblastic leukemia (B-ALL). Such CTL epitopes might be beneficial to shifting vaccination strategies against B-ALL from individual specificity to family specificity.</p><p><b>METHODS</b>Seven IgHV gene families were amplified respectively by PCR and sequenced directly from 71 childhood B-ALL cases. Bioinformatics was applied in analyzing characteristics of sequences available and predicting HLA-A*0201-restricted CTL epitopes for each IgHV family. An antigen-specific T cell expansion system was used to generate peptide-specific CTLs. The cytotoxicity of CTLs against B-ALL cells was assessed in the lactate dehydrogenase release assay.</p><p><b>RESULTS</b>Complete IgHV rearrangements were identified in all of the 71 B-ALL cases. All of 40 sequences available showed > or = 98% homology with the nearest germline IgHV genes, indicating IgHV genes in B-ALL of germline nature. Twelve nonapeptides of high HLA-A*0201-binding scores were obtained from 26 productive IgHV protein sequences. Ten (83%) of the peptides were located in FR1 and FR3 shared among the corresponding IgHV family. CTLs specific for the peptide QLVQSGAEV located in FR1 (3 - 11) shared among the IgHV1 family could be successfully generated from peripheral blood mononuclear cells of two HLA-A*0201 + healthy donors in vitro and were capable of killing HLA-matched B-ALL cell clones belonging to the IgHV1 family.</p><p><b>CONCLUSION</b>Anti-B-ALL CTLs against immunoglobulin heavy chain FR-derived peptides have family-specific cytotoxicity.</p>

Cytogenetic and interphase FISH studies in the diagnosis of malignant lymphomas / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To evaluate the role of cytogenetic study and interphase FISH analysis in differential diagnosis of patients with clinical and/or cytological diagnosis as lymphoma or "suspicious for lymphoma".</p><p><b>METHODS</b>Routine histology, immunohistochemistry, cytogenetics and interphase FISH studies were used to assess 223 cases with superficial lymph nodes of not less than 1. 5 cm in diameter. The probe used in the interphase FISH assays is the Vysis' LSI IGH Dual Color, Break Apart Rearrangement Probe.</p><p><b>RESULTS</b>Based on these studies, forty-four patients were diagnosed as Hodgkin's lymphomas ( HL) , 162 as Non-Hodgkin's lymphomas ( NHL) , 11 with benign diseases and 4 as other malignancies, while the remaining 2 cases were discarded due to tissue necrosis. Using interphase FISH, abnormalities of immunoglobulin heavy chain gene (IGH) were detected in 6/44 (13.6%) and 83/162 (51.2%) in the HIL and NHL cases, respectively, while none was observed in 11 cases with a benign disease (P <0. 001). Combining cytogenetics and FISH studies, the detection rates for HL and NHL cases then increased to 15.9% and 77. 8%, respectively, otherwise, 3 of whom could not have made definite diagnosis.</p><p><b>CONCLUSION</b>Interphase FISH assay is a rapid and sensitive tool for detecting IGH abnormalities. Both cytogenetics and interphase FISH analyses may play a significant role in diagnosis of lymphomas.</p>

Rearrangement of immunoglobulin heavy chain variable region genes in human neonates / 南方医科大学学报

<p><b>OBJECTIVE</b>To study the rearrangement of immunoglobulin (Ig) heavy chain variable region (V(H)) genes in human neonates with different gestational ages (GA).</p><p><b>METHODS</b>Peripheral blood from the neonates with GA of 27 weeks (4 cases), 28-32 weeks (9 cases), 33-36 weeks (12 cases), and 37-42 weeks (13 cases) was collected. RT-PCR was used to amplify the Ig V(H) gene, and the PCR products were separated by electrophoresis and analyzed using 6% denaturing PAGE gel.</p><p><b>RESULTS</b>All Ig V(H) family genes had several rearranged genes in each GA group, and the neonates with different GA showed no significant difference in the median molecular weight for each rearranged Ig V(H) family gene.</p><p><b>CONCLUSION</b>The neonates with GA of 27-42 weeks exhibit diversity in Ig V(H) gene rearrangement, and for the same Ig V(H) family, the median length of the arranged Ig V(H) genes is independent of the gestational age.</p>

Diversification of Immunoglobulin Heavy Chain Genes in Bovine IPP Follicles / 대한면역학회지

No abstract available.