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Grade 3B follicular lymphoma (G3B FL) is rare, accounting for only 5-10% of FLs. Not only has it been routinely excluded from clinical trials, but data published on diagnosis, outcomes, choice of therapies and role of imaging are conflicting. With the advent of increasingly diverse treatment options for low-grade (G1-3A) FL, and the molecular subcategorisation of high-grade B-cell lymphomas, characterisation and treatment of G3B FL is ever more important as extrapolation of data becomes more difficult. New data have emerged exploring unique genetic characteristics, specific features on positron emission tomography imaging, choice of therapy, and outcomes of G3B FL in the current era. The present review will summarise and appraise these new data, and offer recommendations based on current evidence., (© 2021 British Society for Haematology and John Wiley & Sons Ltd.)

Myeloid/lymphoid neoplasms with eosinophilia and gene rearrangement are a unique category in the WHO classification, and include cases with rearrangement of PDGFRA, PDGFRB, FGFR1, and PCM1-JAK2. We report three patients presented with eosinophilia and FLT3 rearrangement: the first case with chronic eosinophilic leukemia, not otherwise specified and T-lymphoblastic leukemia/lymphoma; the second case with myeloid sarcoma; and the last case with high-grade myelodysplastic syndrome. The first case showed t(13;14)(q12;q32), which encoded FLT3-TRIP11. The patient was treated with intense chemotherapy and subsequently sorafenib with clinical improvement. Unfortunately, the patient showed persistent residual disease and passed away 9 months after the diagnosis from pneumonia. The other two cases both showed ETV6-FLT3. The second patient was treated with local radiation and systemic chemotherapy including sorafenib and was alive. The third patient was treated with chemotherapy but showed transformation to acute myeloid leukemia and died 15 months after diagnosis. These cases are among a growing number of cases with FLT3 rearrangement that all showed similar clinicopathologic features characterized by myeloproliferative neoplasm with eosinophilia and frequent T lymphoblastic leukemia/lymphoma. Therefore, we propose that the myeloid/lymphoid neoplasms with eosinophilia and FLT3 rearrangement be included in the WHO category of myeloid/lymphoid neoplasms with eosinophilia and gene rearrangement., (Copyright © 2020. Published by Elsevier Ltd.)

The clinical impact of minimal residual disease detection at early time points or during follow-ups has been shown to accurately predict relapses among patients with lymphomas, mainly in follicular and diffuse large B cell lymphoma. The field of minimal residual disease testing in mantle cell lymphoma is still evolving but has great impact in determining the prognosis. Flow cytometry and polymerase chain reaction-based testing are most commonly used methods in practice; however, these methods are not sensitive enough to detect the dynamic changes that underline lymphoma progression. Newer methods using next-generation sequencing, such as ClonoSeq, are being incorporated in clinical trials. Other techniques under evolution include CAPP-seq and anchored multiplex polymerase chain reaction-based methods. This review article aims to provide a comprehensive update on the status of minimal residual disease detection and its prognostic effect in mantle cell patients. The role of circulating tumor DNA-based minimal residual disease detection in lymphomas is also discussed.

Background: Multiple Myeloma (MM) is a hematological malignancy with genomic heterogeneity and poor survival outcome. Apart from the central role of genetic lesions, epigenetic anomalies have been identified as drivers in the development of the disease., Methods: Alterations in the DNA methylome were mapped in 52 newly diagnosed MM (NDMM) patients of six molecular subgroups and matched with loci-specific chromatin marks to define their impact on gene expression. Differential DNA methylation analysis was performed using DMAP with a ≥10% increase (hypermethylation) or decrease (hypomethylation) in NDMM subgroups, compared to control samples, considered significant for all the subsequent analyses with p<0.05 after adjusting for a false discovery rate., Results: We identified differentially methylated regions (DMRs) within the etiological cytogenetic subgroups of myeloma, compared to control plasma cells. Using gene expression data we identified genes that are dysregulated and correlate with DNA methylation levels, indicating a role for DNA methylation in their transcriptional control. We demonstrated that 70% of DMRs in the MM epigenome were hypomethylated and overlapped with repressive H3K27me3. In contrast, differentially expressed genes containing hypermethylated DMRs within the gene body or hypomethylated DMRs at the promoters overlapped with H3K4me1, H3K4me3, or H3K36me3 marks. Additionally, enrichment of BRD4 or MED1 at the H3K27ac enriched DMRs functioned as super-enhancers (SE), controlling the overexpression of genes or gene-cassettes., Conclusions: Therefore, this study presents the underlying epigenetic regulatory networks of gene expression dysregulation in NDMM patients and identifies potential targets for future therapies.

In multiple myeloma (MM), MYC rearrangements that result in increased MYC expression are associated with an aggressive form of MM and adverse outcome. However, the consequences of MYC amplification in MM remain unclear. Here, we describe an unusual case of plasma cell leukemia (PCL) harboring MYC amplification on double minute chromosomes (dmin). A 79-year-old woman was initially diagnosed as having BJP-κ type MM with bone lesions. After seven months, the disease progressed to secondary PCL: leukocytes 49.1 × 10 9 /L with 77% plasma cells showing lymphoplasmacytic appearance. The bone marrow was infiltrated with 76% plasma cells immunophenotypically positive for CD38 and negative for CD45, CD19, CD20, and CD56. The karyotype by G-banding and spectral karyotyping was 48,XX,der(14)t(11;14)(q13;q32),+der(14)t(14;19)(q32;q13.1),+18,6~95dmin[15]/46,XX[5]. Fluorescence in situ hybridization detected multiple MYC signals on dmin and double IGH/CCND1 fusion signals on der(14)t(11;14) and der(14)t(14;19). Most plasma cells were diffusely and strongly positive for MYC and CCND1 by immunohistochemistry. The patient died of progressive disease after one week. MYC amplification led to high expression of MYC and rapid disease progression, indicating its clinical significance in the pathogenesis of MM/PCL. MYC amplification on dmin may be a very rare genetic event closely associated with the progression to PCL and coexistence of IGH/CCND1 fusions., Competing Interests: Declaration of Competing Interest Dr. Minami reports honoraria from Janssen, Novartis, and Ono, and research grant from Ono. Other authors have no conflict of interest., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Hereditary spherocytosis (HS) is a heterogeneous genetic disorder characterized by spherocytosis on peripheral blood smear with hemolytic anemia, accompanied by signs of hemolysis. Herein, we report a 5-month-old Korean girl with HS resulting from a de novo 271 Kb microdeletion of 14q23.3. She presented with hemolytic anemia and mild splenomegaly. Spherocytosis was seen on examination of peripheral blood. Eosin-5'-maleimide (EMA) test and flow cytometric osmotic fragility test were positive. She had no relevant family history of spherocytosis. No pathogenic single nucleotide variants or small insertions/deletions were detected in HS-associated genes. Array comparative genomic hybridization analysis revealed a 271 Kb deletion at chromosome 14q23.3, encompassing the SPTB, CHURC1, GPX2, RAB15, FNTB, and MAX genes. We found a deletion affecting 5' UTR, exon 1, and part of intron 1 of the SPTB gene using targeted next-generation sequencing (NGS) analysis, suggesting that NGS may be able to identify disease-causing copy number variations (CNVs), as well as small point mutations in HS patients. In addition, chromosomal microarray may be useful in defining combined deleted genes. Additional evaluations should thus be considered in the diagnosis of HS, especially when CNV is revealed as disease-causing abnormality.

The Myeloma X trial (ISCRTN60123120) registered patients with relapsed multiple myeloma. Participants were randomised between salvage autologous stem cell transplantation (ASCT) or weekly cyclophosphamide following re-induction therapy. Cytogenetic analysis performed at trial registration defined t(4;14), t(14;16) and del(17p) as high-risk. The effect of cytogenetics on time to progression (TTP) and overall survival was investigated. At 76 months median follow-up, ASCT improved TTP compared to cyclophosphamide (19 months (95% confidence interval [95% CI] 16-26) vs. 11 months (9-12), hazard ratio [HR]: 0·40, 95% CI: 0·29-0·56, P < 0·001), on which the presence of any single high-risk lesion had a detrimental impact [likelihood ratio test (LRT): P = 0·011]. ASCT also improved OS [67 months (95% CI 59-not reached) vs. 55 months (44-67), HR: 0·64, 95% CI: 0·42-0·99, P = 0·0435], with evidence of a detrimental impact with MYC rearrangement (LRT: P = 0·021). Twenty-one (24·7%) cyclophosphamide patients received an ASCT post-trial, median OS was not reached (95% CI: 39-not reached) for these participants compared to 31 months (22-39), in those who did not receive a post-trial ASCT. The analysis further supports the benefit of salvage ASCT, which may still be beneficial after second relapse in surviving patients. There is evidence that this benefit reduces in cytogenetic high-risk patients, highlighting the need for targeted study in this patient group., (© 2019 The Authors. British Journal of Haematology published by British Society for Haematology and John Wiley & Sons Ltd.)

Decoding the spatial organizations of chromosomes has crucial implications for studying eukaryotic gene regulation. Recently, chromosomal conformation capture based technologies, such as Hi-C, have been widely used to uncover the interaction frequencies of genomic loci in a high-throughput and genome-wide manner and provide new insights into the folding of three-dimensional (3D) genome structure. In this paper, we develop a novel manifold learning based framework, called GEM (Genomic organization reconstructor based on conformational Energy and Manifold learning), to reconstruct the three-dimensional organizations of chromosomes by integrating Hi-C data with biophysical feasibility. Unlike previous methods, which explicitly assume specific relationships between Hi-C interaction frequencies and spatial distances, our model directly embeds the neighboring affinities from Hi-C space into 3D Euclidean space. Extensive validations demonstrated that GEM not only greatly outperformed other state-of-art modeling methods but also provided a physically and physiologically valid 3D representations of the organizations of chromosomes. Furthermore, we for the first time apply the modeled chromatin structures to recover long-range genomic interactions missing from original Hi-C data.

Maintaining genome integrity is crucial for normal cellular functions. DNA double-strand breaks (DSBs), when unrepaired, can potentiate chromosomal translocations. t(14;18) translocation involving BCL2 gene on chromosome 18 and IgH loci at chromosome 14, could lead to follicular lymphoma. Molecular basis for fragility of translocation breakpoint regions is an active area of investigation. Previously, formation of non-B DNA structures like G-quadruplex, triplex, B/A transition were investigated at peak I of BCL2 major breakpoint region (MBR); however, it is less understood at peak III. In vitro gel shift assays show faster mobility for MBR peak III sequences, unlike controls. CD studies of peak III sequences reveal a spectral pattern different from B-DNA. Although complementary C-rich stretches exhibit single-strandedness, corresponding guanine-rich sequences do not show DMS protection, ruling out G-quadruplex and triplex DNA. Extrachromosomal assay indicates that peak III halts transcription, unlike its mutated version. Taken together, multiple lines of evidence suggest formation of potential cruciform DNA structure at MBR peak III, which was also supported by in silico studies. Thus, our study reveals formation of non-B DNA structure which could be a basis for fragility at BCL2 breakpoint regions, eventually leading to chromosomal translocations., (Copyright © 2017 Elsevier B.V. All rights reserved.)

The genetic abnormalities underlying multiple myeloma (MM) are notoriously complex and intraclonal heterogeneity is a common disease feature. In the current study, we describe the establishment of a monoclonal immunoglobulin A (IgA) kappa (κ) MM cell line designated MC-B11/14. Cytogenetic and fluorescence in situ hybridization analyses of the original and relapse patient samples revealed that the MM clone was nonhyperdiploid and possessed an 11;14 chromosomal translocation. The MC-B11/14 cell line, established from the relapse sample, is tetraploid and houses the t(11;14) abnormality. Given our long-standing interest in Ig function and secretion, we next used CRISPR technology to knock out IgA heavy-chain expression in the MC-B11/14 cells to assess the biological consequences of converting this cell line to one only expressing κ light chains. As expected, secretion of intact IgA was undetectable from MC-B11/14 IgA- cells. Sensitivity to pomalidomide treatment was similar between the MC-B11/14 WT and MC-B11/14 IgA- cells; however, MC-B11/14 IgA- cells were found to be significantly more resistant to bortezomib treatment. This study describes the establishment of a new human MM cell line tool with which to study disease biology and the use of CRISPR technology to create a potentially useful model with which to study MM light-chain escape., (Copyright © 2018 ISEH – Society for Hematology and Stem Cells. Published by Elsevier Inc. All rights reserved.)

Disease Overview: Follicular lymphoma is generally an indolent B cell lymphoproliferative disorder of transformed follicular center B cells. Follicular lymphoma (FL) is characterized by diffuse lymphoadenopathy, bone marrow involvement, splenomegaly, and less commonly other extranodal sites of involvement. In general cytopenias can occur but constitutional symptoms of fever, nightsweats, and weight loss are uncommon., Diagnosis: Diagnosis is based on histology of preferably a biopsy of a lymph node. Immunohistochemical staining is positive in virtually all cases for cell surface CD19, CD20, CD10, and monoclonal immunoglobulin, as well as cytoplasmic expression of bcl-2 protein. The overwhelming majority of cases have the characteristic t(14;18) translocation involving the IgH/bcl-2 genes., Risk Stratification: The Follicular Lymphoma International Prognostic Index prognostic model for FL uses five independent predictors of inferior survival: age >60 years, hemoglobin <12 g/dL, serum LDH > normal, Ann Arbor stage III/IV, number of involved nodal areas > 4. The presence of 0, 1, 2, and  ≥ 3 adverse factors defines low, intermediate, and high-risk disease. With the use of more modern therapies, outcomes have improved., Risk-Adapted Therapy: Observation continues to be adequate for asymptomatic patients with low bulk disease and no cytopenias. For patients needing therapy, most patients are treated with chemotherapy plus rituximab, which has improved response rates, duration of response and overall survival. Randomized studies have shown additional benefit for maintenance rituximab both following chemotherapy-rituximab and single agent rituximab. Experimental therapies as well as stem cell transplantation (SCT) are considered for recurrent disease., (Copyright © 2014 Wiley Periodicals, Inc.)

The International Myeloma Working Group recommends that fluorescence in situ hybridization (FISH) be performed on specifically identified plasma cells (PC). This is because chromosomal abnormalities are not frequently detected by traditional karyotyping due to the low proliferative rate of PC in multiple myeloma (MM). Conventional FISH enhances the sensitivity but lacks the specificity, as it does not distinguish PC from other hematopoetic cells. To fulfill this recommendation, PC need to be selected either by flow cytometry or immunomagnetic bead-based PC sorting or by concomitant labeling of the cytoplasmic immunoglobulin light chain, which allows for unambiguous identification. These techniques require expertise, time, and funding and are not easily incorporated into the routine workflow of the cytogenetic laboratory. We have modified and refined the technique using fixed cell pellets to achieve nicely separated and easily identifiable PC. With immunostaining and subsequent FISH (i.e., cytoplasmic immunoglobulin FISH, cIg-FISH), this technique can be easily incorporated into every cytogenetic laboratory. Twenty samples from patients with MM were subjected to routine FISH, cIg-FISH, and chromosomal karyotyping and the results were compared. Three FISH probes, which enabled detection of the t(4;14), t(14;16) and deletion of TP53, were used to validate this modified technique successfully., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Disease Overview: Mantle cell lymphoma (MCL) is a non-Hodgkin lymphoma characterized by involvement of the lymph nodes, spleen, blood, and bone marrow with a short remission duration to standard therapies and a median overall survival of 4-5 years., Diagnosis: Diagnosis is based on lymph node, bone marrow, or tissue morphology of centrocytic lymphocytes, small cell type, or blastoid variant cells. A chromosomal translocation t(11:14) is the molecular hallmark of MCL, resulting in the overexpression of cyclin D1. Cyclin D1 is detected by immunohistochemistry in 98% of cases. The absence of SOX-11 or a low Ki-67 may correlate with a more indolent form of MCL. The differential diagnosis of MCL includes small lymphocytic lymphoma, marginal zone lymphoma, and follicular lymphoma., Risk Stratification: The Mantle Cell Lymphoma International Prognostic Index (MIPI) is the prognostic model most often used and incorporates ECOG performance status, age, leukocyte count, and lactic dehydrogenase. A modification of the MIPI also adds the Ki-67 proliferative index if available. The median overall survival (OS) for the low risk group was not reached (5-year OS of 60%). The median OS for the intermediate risk group was 51 months and 29 months for the high risk group., Risk-Adapted Therapy: For selected indolent, low MIPI MCL patients, initial observation may be appropriate therapy. For younger patients with intermediate or high risk MIPI MCL, aggressive therapy with a cytarabine containing regimen ± autologous stem cell transplantation should be considered. For older MCL patients with intermediate or high risk MIPI, combination chemotherapy with R-CHOP, R-Bendamustine, or a clinical trial should be considered. At the time of relapse, agents directed at activated pathways in MCL cells such as bortezomib (NFkB inhibitor) or lenalidamide (anti-angiogenesis) are approved agents. Clinical trials with Ibruitinib (Bruton's Tyrosine Kinase inhibitor) or Idelalisib (PI3K inhibitor) have demonstrated excellent clinical activity in MCL patients. Autologous or allogeneic stem cell transplantation can also be considered in young patients., (Copyright © 2013 Wiley Periodicals, Inc.)

Disease Overview: Follicular lymphoma (FL) is generally an indolent B-cell lymphoproliferative disorder of transformed follicular center B cells. FL is characterized by diffuse lymphoadenopathy, involvement of bone marrow, splenomegaly, and less commonly other extranodal sites of involvement. In general, cytopenias can occur but constitutional symptoms of fever, night sweats, and weight loss are uncommon., Diagnosis: Diagnosis is based on histology of preferably a biopsy of a lymph node. Immunohistochemical staining is positive in virtually all cases for cell surface CD19, CD20, CD10, and monoclonal immunoglobulin, as well as cytoplasmic expression of bcl-2 protein. The overwhelming majority of cases have the characteristic t(14;18) translocation involving the IgH/bcl-2 genes., Risk Stratification: The FL International Prognostic Index prognostic model for FL uses five independent predictors of inferior survival: age > 60 years, hemoglobin < 12 g/dL, serum lactate dehydrogenase > normal, Ann Arbor stage III/IV, number of involved nodal areas > 4. The presence of 0, 1, 2, and ≥ 3 adverse factors defines low, intermediate, and high-risk disease with median 10-year survivals in the pre-rituximab era of ~71, 51, and 36 months, respectively. With the use of more modern therapies, specifically anti-CD20 monoclonal antibody, the outcome has improved., Risk-Adapted Therapy: Observation continues to be adequate for asymptomatic patients with low bulk disease and no cytopenias. For patients needing therapy, most patients are treated with chemotherapy plus rituximab, which has improved response rates, duration of response, and overall survival. Randomized studies have shown additional benefit for maintenance rituximab both following chemotherapy-rituximab and single-agent rituximab. Autologous stem cell transplantation (SCT) has not shown a survival benefit in first remission patients. SCT including both autologous and allogeneic SCT or experimental agent therapy is considered for recurrent disease., (Copyright © 2012 Wiley Periodicals, Inc.)

The hallmark t(14;18)(q32;q21) in follicular lymphoma (FL) results in constitutive overexpression of the BCL2 protein, allowing B cells to abrogate the default germinal center apoptotic program. Most tumors are characterized by recurrent secondary genetic alterations including genomic gains, losses, and mutations, some providing a growth advantage, including alterations in MLL2, EPHA7, TNFRSF14, and EZH2. The sequence in which these events occur and how they contribute to progression and ultimately to transformation is unclear. Lastly, crosstalk between neoplastic B cells and non-neoplastic immune and stromal cells in the microenvironment plays an important role in sustaining tumor cell growth, cultivating immune privilege, and promoting transformation.

Mantle cell lymphoma is a B cell malignancy in which constitutive dysregulation of cyclin D1 and the cell cycle, disruption of DNA damage response pathways, and activation of cell survival mechanisms contribute to oncogenesis. A small number of tumors lack cyclin D1 overexpression, suggesting that its dysregulation is always not required for tumor initiation. Some cases have hypermutated IGHV and stable karyotypes, a predominant nonnodal disease, and an indolent clinical evolution, which suggests that they may correspond to distinct subtypes of the disease. In this review, we discuss the molecular pathways that contribute to pathogenesis, and how improved understanding of these molecular mechanisms offers new perspectives for the treatment of patients.

Disease Overview: Mantle cell lymphoma (MCL) is a non-Hodgkin lymphoma characterized by involvement of the lymph nodes, spleen, blood, and bone marrow with a short remission duration to standard therapies and a median overall survival of 4-5 years., Diagnosis: Diagnosis is based on lymph node, bone marrow, or tissue morphology of centrocytic lymphocytes, small cell type, or blastoid variant cells. A chromosomal translocation t(11:14) is the molecular hallmark of MCL, resulting in the overexpression of cyclin D1. Cyclin D1 is detected by immunohistochemistry in 98% of cases. The absence of SOX-11 or a low Ki-67 may correlate with a more indolent form of MCL. The differential diagnosis of MCL includes small lymphocytic lymphoma, marginal zone lymphoma, and follicular lymphoma., Risk Stratification: The mantle cell lymphoma international prognostic index (MIPI) is the prognostic model most often used and incorporates ECOG performance status, age, leukocyte count, and lactic dehydrogenase. A modification of the MIPI also adds the Ki-67 proliferative index if available. The median overall survival (OS) for the low-risk group was not reached (5-year OS of 60%). The median OS for the intermediate risk group was 51 and 29 months for the high-risk group., Risk-Adapted Therapy: For selected indolent, low MIPI MCL patients, initial observation may be appropriate therapy. For younger patients with intermediate or high risk MIPI MCL, aggressive therapy with a cytarabine containing regimen ± autologous stem cell transplantation should be considered. For older MCL patients with intermediate or high risk MIPI, combination chemotherapy with R-CHOP, R-Bendamustine, or a clinical trial should be considered. At the time of relapse, agents directed at activated pathways in MCL cells such as bortezomib (NFkB inhibitor), BTK inhibitors or CAL-101 (B-cell receptor inhibitors) or lenalidamide (antiangiogenesis) have clinical activity in MCL patients. Autologous or allogeneic stem cell transplantation can also be considered in young patients., (Copyright © 2012 Wiley Periodicals, Inc.)

This study evaluated the loss and expression level of miRNAs 14q32 clusters in acute lymphoblastic leukemia (ALL) patients with cryptic deletions at 14q32 chromosomal band to investigate their involvement in this disease. We demonstrate that a subset of ALL cases bearing 14q32 LOH showed a down-regulation of miRNA 14q32 clusters, which is directly linked to the submicroscopic chromosomal deletion. As a consequence of miRNAs deregulation we reported an inverse correlation with the expression of their target BCL11a, a transcription factor involved in lymphoid differentiation. These results suggest that 14q32/miRNA clusters LOH may be another mechanism involved in lymphoid B cell transformation and differentiation and therefore, could be used as a diagnostic marker and therapeutic target in subsets of ALL., ((c) 2010 Wiley-Liss, Inc.)

Aneuploidy is a very common prognostic factor in multiple myeloma (MM). Nonhyperdiploidy including near-tetraploidy (NT) is a poor prognostic indicator, compared to hyperdiploidy in multiple myeloma (MM). NT results from endoduplication of hypodiploidy. We report of a 55-year-old female patient diagnosed with advanced stage MM with hyperdiploidy and t(8;14)(q24;q32). The patient responded well to lenalidomide and dexamethasone for approximately 1 year. At the time of progression, she had become unresponsive to lenalidomide and subsequently bortezomib, and was found to have NT and loss of choromosome 13. There is another reported patient who had a possible interchange from nonhyperdiploidy to hyperdiploidy status, however, artifact could not be ruled out. To our knowledge, this is the first patient in whom evolution of an abnormal clone from a hyperdiploidy to a NT abnormal clone has been confirmed during the natural course of MM. This evolution is associated with resistance to novel drugs and poor prognosis in MM., (Copyright 2010 Elsevier Ltd. All rights reserved.)

Sjögren's syndrome (SS) is an autoimmune disease characterized by clonal B cell attack of the exocrine glands and dysregulated expression of B cell-activating factor (BAFF). Based upon the current data of increased rates of lymphoid malignancy, as non-Hodgkin's lymphoma (NHL) is associated with SS, we propose the detection of clonal rearrangements of immunoglobulin heavy chain (IgH) gene in those patients as a predictor of malignant clonal expansion. To test our proposal, we examined the IgH clonal rearrangements in SS patients (60) and healthy control subjects (42) having chronic non-specific sialadenitis, to determine the presence of clonal B cells in minor labial salivary glands (MSG) of SS patients. Clonal B cell expansion was assessed by two polymerase chain reaction (PCR) assays: (i) semi-nested PCR, against sequences encoding framework regions FR3, FR2 and FR1c of the variable chain IgH gene in B cells present in the MSG infiltrate; and (ii) the PCR-enzyme-linked immunosorbent assay (ELISA) technique, against the major and minor breakpoint regions of the Bcl-2 oncogene coupled with a variable segment of the IgH to assess the Bcl-2/JH translocation. When FR3, FR2 and FR1c primers were employed, we detected B cell monoclonality in 87% of the SS patients and 19% of the control subjects. The association between inflammation severity of the MSG pattern and the presence of B cell clonality was found to be statistically significant (P<0.01). We concluded that the presence of B cell clonality in MSG can be used as a index of an altered microenvironment favouring the development of lymphoma in SS patients.

Twenty-five dicentric small supernumerary marker chromosomes (sSMC) derived from #13/21, #14, #15, #18, and #22 were studied by immunohistochemistry for their centromeric activity. Centromere protein (CENP)-B was applied as marker for all centromeres and CENP-C to label the active ones. Three different 'predominant' activation patterns could be observed, i.e., centric fusion or either only one or all two centromeres were active. In one inherited case, the same activation pattern was found in mother and son. In acrocentric-derived sSMC, all three activation patterns could be present. In contrary, in chromosome 18-derived sSMC, only the fusion type was observed. In concordance with previous studies a certain centromeric plasticity was observed in up to 13% of the cells of an individual case. Surprisingly, the obtained data suggests a possible influence of the sSMC carrier's gender on the implementation of the predominant activation pattern; especially, only one active centromere was found more frequently in female than in male carriers. Also, it might be suggested that dicentric sSMC with one active centromere could be less stable than such with two active ones-centromeric plasticity might have an influence here, as well. Also, centromere activity in acrocentric-derived dicentrics could be influenced by heteromorphisms of the corresponding short arms. Finally, evidence is provided that the closer the centromeres of a dicentric are and if they are not fused, the more likely it was that both of them became active. In concordance and refinement with previous studies, a distance of 1.4 Mb up to about 13 Mb the two active centromere state was favored, while centromeric distance of over approximately 15 Mb lead to inactivation of one centromere. Overall, here, the first and largest ever undertaken study in dicentric sSMC is presented, providing evidence that the centromeric activation pattern is, and parental origin may be of interest for their biology. Influence of mechanisms similar or identical to meiotic imprinting in the centromeric regions of human chromosomes might be present. Furthermore, centromeric activation pattern could be at least in parts meaningful for the clinical outcome of dicentric sSMC, as sSMC stability and mosaicism can make the difference between clinically normal and abnormal phenotypes.

Objective: Interleukin (IL)-21, a member of the IL-2 family, has antitumor activity and is now being tested in non-Hodgkin's lymphoma in combination with anti-CD20 antibodies. IL-21 may either induce apoptosis or promote growth in different lymphoid malignancies. We therefore investigated the IL-21/IL-21R system in follicular lymphoma (FL) cells., Materials and Methods: IL-21R expression was studied by reverse transcription polymerase chain reaction, immunofluorescence, and Western blot analyses. Apoptosis was measured by Annexin-V-propidium iodide staining. Signaling via IL-21R was studied using antibodies specific for phosphorylated Janus-activating kinase and signal transducers and activators of transcription proteins by Western Blot., Results: IL-21R was found on primary FL cells in 15 of 15 cases at diagnosis and IL-21 increased apoptosis in 10 of 10 FL samples. However, cells from areas of diffuse growth in FL and from two diffuse lymphomas evolved from previous FL, showed low IL-21R expression. The latter were also resistant to IL-21-mediated apoptosis. Among lymphoma cell lines bearing the t(14;18) translocation, only 1 of 7 showed increased apoptosis in response to IL-21 stimulation. This cell line was IL-21R-positive, whereas five of six nonresponsive cell lines showed very low IL-21R expression. Intriguingly, one of the IL-21-resistant cell lines (DOHH2) expressed high levels of IL-21R. Treatment with IL-21 or IL-4 upregulated suppressor of cytokine signaling 3 gene expression in the IL-21-responsive cell line, but not in DOHH2 cells, which showed defective Janus-activating kinase/signal transducers and activators of transcription signaling in response to IL-21, in relationship to the lack of Janus-activating kinase 3 gene expression., Conclusion: These data indicate that low IL-21R expression or defective signal transduction downstream IL-21R may cause refractoriness to IL-21-mediated effects in some FL cells., (2010 ISEH-Society for Hematology and Stem Cells. Published by Elsevier Inc. All rights reserved.)

A novel microdeletion of 14q13.1q13.3 was identified in a patient with developmental delay and intractable epilepsy. The 2.2-Mb deletion included 15 genes, of which TULIP1 (approved gene symbol: RALGAPA1)was the only gene highly expressed in the brain. Western blotting revealed reduced amount of TULIP1 in cell lysates derived from immortalized lymphocytes of the patient, suggesting the association between TULIP1 haploinsufficiency and the patient's phenotype, then 140 patients were screened for TULIP1 mutations and four missense mutations were identified. Although all four missense mutations were common with parents, reduced TULIP1 was observed in the cell lysates with a P297T mutation identified in a conserved region among species. A full-length homolog of human TULIP1 was identified in zebrafish with 72% identity to human. Tulip1 was highly expressed in zebrafish brain, and knockdown of which resulted in brain developmental delay. Therefore, we suggest that TULIP1 is a candidate gene for developmental delay.

Familial breast cancer represents up to 5% of all breast cancer cases. Recently, our group has performed a new SNP-based linkage study in 19 non-BRCA1/2 families. We found that a single family was linked to regions in two different chromosomes (11q13 and 14q21), and observed a non-parametric LOD score of 11.5 in both regions. In the present study, we ruled out any possible translocation between the chromosomes. We also used both a panel of STRs and an indirect approach based on HapMap data to narrow down these regions from 28 to 7 Mb in chromosome 11 and from 14.5 to 8.5 Mb in chromosome 14. We performed a mutational screening on candidate genes in 11q13 (NUMA1, FGF3, CCND1, RAD9A, RNF121, FADD and hsa-mir-192), and on FOXA1 in 14q21. Although we have not found any deleterious mutations in the coding region of these genes, data from STR markers confirm 11q13 as a candidate region to contain a breast cancer susceptibility gene.

RhoA, a member of the Rho family of small GTPases, directs the organization of the actin cytoskeleton and is involved in regulating cell shape and movement. Its activity is negatively regulated by p190-B RhoGAP (GTPase-activating protein). We investigated DNA copy number aberrations in human hepatocellular carcinoma and esophageal squamous cell carcinoma cell lines using a high-density oligonucleotide microarray and found a novel amplification at chromosomal region 14q12. We identified ARHGAP5 (the gene encoding p190-B RhoGAP) as a probable target for the amplification at 14q12, and our results showed that p190-B RhoGAP promotes cells spreading and migration by negatively regulating RhoA activity in Huh-7 hepatocellular carcinoma cells.

Oncogenes involved in recurrent chromosomal translocations serve as diagnostic markers and therapeutic targets in hematopoietic tumors. In contrast to myeloid and B-cell neoplasms, translocations in peripheral T-cell lymphomas (PTCLs) are poorly understood. Here, we identified recurrent translocations involving the multiple myeloma oncogene-1/interferon regulatory factor-4 (IRF4) locus in PTCLs. IRF4 translocations exist in myeloma and some B-cell lymphomas, but have not been reported earlier in PTCLs. We studied 169 PTCLs using fluorescence in situ hybridization and identified 12 cases with IRF4 translocations. Two cases with t(6;14)(p25;q11.2) had translocations between IRF4 and the T-cell receptor-alpha (TCRA) locus. Both were cytotoxic PTCLs, unspecified (PTCL-Us) involving bone marrow and skin. In total, 8 of the remaining 10 cases were cutaneous anaplastic large-cell lymphomas (ALCLs) without TCRA rearrangements (57% of cutaneous ALCLs tested). These findings identified IRF4 translocations as a novel recurrent genetic abnormality in PTCLs. Cytotoxic PTCL-Us involving bone marrow and skin and containing IRF4/TCRA translocations might represent a distinct clinicopathologic entity. Translocations involving IRF4 but not TCRA appear to occur predominantly in cutaneous ALCLs. Detecting these translocations may be useful in lymphoma diagnosis. Further, due to its involvement in translocations, MUM1/IRF4 protein may play an important biologic role in some PTCLs, and might represent a possible therapeutic target.