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B-cell Malignancies (b-cell + malignancy)
Selected AbstractsSignificance of lymphoglandular bodies in bone marrow aspiration smearsDIAGNOSTIC CYTOPATHOLOGY, Issue 4 2001Robert C. Stern M.D. Abstract The presence of lymphoglandular bodies (LGB) or Söderström bodies is often stated to be a feature of lymphoid processes. In our experience, LGB are typically identified in B-cell processes but not in T-cell lymphomas or myeloid leukemias. We reviewed 136 bone marrow aspirate smears. The number of LGB per five high-power fields was counted, and median counts for B-cell processes, non-B-cell processes, myeloid leukemias, and T-cell malignancies were obtained and compared by the Wilcoxon rank sum test. Bone marrow aspirate smears involved with B-cell malignancies contained a median of 30 (range, 1,250) LGB per five high-power fields. Compared to myeloid leukemias (median, 11; range, 1,253) and T-cell malignancies (median, 7; range, 0,41), the differences were statistically significant (P < 0.001 and P = 0.01, respectively). While lymphoglandular bodies can be seen in a variety of malignant hematopoietic and nonhematopoietic disorders, they are found in significantly greater numbers in B-cell malignancies. Diagn. Cytopathol. 24:240,243, 2001. © 2001 Wiley-Liss, Inc. [source] TCL1 is activated by chromosomal rearrangement or by hypomethylationGENES, CHROMOSOMES AND CANCER, Issue 4 2001Martin R. Yuille TCL1 is an oncogene activated by recurrent reciprocal translocations at chromosome segment 14q32.1 in the most common of the mature T-cell malignancies, T-cell prolymphocytic leukemia. It acts to transport Akt1 to the nucleus and enhance Akt1's serine-threonine kinase activity. TCL1 is also expressed in the B-cell malignancy, Burkitt's lymphoma (BL). However, 14q32.1 breakpoints have not been detected in BL, and we therefore investigated in more detail how expression was activated. No evidence for rearrangement near TCL1 was found in BL. Instead, a NotI site adjacent to the TATA box in the TCL1 promoter was found to be unmethylated. By contrast, tumor cell lines not expressing TCL1 were fully methylated at this NotI site, while normal somatic cells were hemimethylated. We also found that TCL1 was expressed in B-cell chronic lymphocytic leukemia (CLL) and the related disorder splenic lymphoma with villous lymphocytes (unlike in normal mature B-cells), and that the NotI site was unmethylated on both alleles. This correlation of repression and methylation was tested in vitro. When cells with both alleles methylated at the NotI site were demethylated, TCL1 expression was induced. These data provide evidence that in mature B-cell malignancies there is an alternative mechanism of TCL1 activation that apparently involves loss of methylation of one promoter allele. We discuss the significance of this for CLL tumorigenesis and for genomewide hypomethylation in CLL. © 2001 Wiley-Liss, Inc. [source] In vitro Epstein-Barr virus-immortalized lymphoma cell line carrying t(9;14)(p13;q32) chromosome abnormality, derived from splenic lymphoma with villous lymphocytesINTERNATIONAL JOURNAL OF CANCER, Issue 2 2006Masanori Daibata Abstract We herein describe splenic lymphoma with villous lymphocytes (SLVL) carrying t(9;14)(p13;q32). The t(9;14)(p13;q32) is a rare reciprocal chromosome translocation found in a subset of B-cell malignancies, mainly in low-grade non-Hodgkin's lymphomas. In t(9;14)(p13;q32), PAX-5 gene on 9p13 is involved with the immunoglobulin heavy-chain gene on 14q32. It has been thought that the deregulated expression of PAX-5 as a result of t(9;14)(p13;q32) may contribute to abnormal cell proliferation. Although continuous cell lines are invaluable tools for studying lymphomagenesis in the t(9;14)(p13;q32)-bearing lymphomas, establishment of such cell lines is extremely difficult since they are usually mature B-cell malignancies. In an attempt to transform the SLVL cells into a proliferating cell line, we examined the responses of the cells to infection by Epstein-Barr virus (EBV). SLVL cells were found to be susceptible to immortalization by EBV, resulting in a permanent cell line. The cell line, designated SL-15, possessed the t(9;14)(p13;q32). Genotype analysis and immunophenotype profiles confirmed that the cell line arose from the primary lymphoma cells. The cells had characteristic cytoplasmic villi. SL-15 cells has been growing over 2 years equivalent to 350,400 population doubling levels without proliferative crisis that is often observed in EBV-positive lymphoblastoid cell lines. Furthermore, SL-15 cells, when inoculated into nude mice, formed t(9;14)(p13;q32)-bearing tumors with cytoplasmic villi. The validated SLVL-derived cell line provide a useful model system to study molecular biology of t(9;14)(p13;q32)-bearing B-cell malignancies as well as lymphomagenesis of SLVL in vitro and in vivo. © 2005 Wiley-Liss, Inc. [source] Rituximab: Applications in dermatologyINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 10 2006Mitra M. Fatourechi Rituximab is a chimeric anti-CD20 monoclonal antibody which has been used extensively for B-lymphocytic malignancies. In addition, applications for autoimmune diseases have emerged in recent years. Case reports support the use of rituximab in certain dermatologic conditions, including paraneoplastic pemphigus, pemphigus vulgaris, graft versus host disease, and cutaneous B-cell malignancies. Clinical trials are lacking and would be an appropriate next step. [source] Dissimilar aggregation processes govern precipitation and gelation of human IgM cryoglobulinsJOURNAL OF MOLECULAR RECOGNITION, Issue 2 2007Vicky Vallas Abstract Cryoglobulinemia is associated with a range of diseases including rheumatoid arthritis, B-cell malignancies, and chronic viral infections. This "cold-sensitivity" condition is caused by cryoglobulins that precipitate, gel, or occasionally crystallize in the cold. Clinical manifestations vary widely in severity, depending on many factors, including the type of cryoglobulin (monoclonal or mixed immunoglobulins) and the physical nature of the aggregates (precipitate, gel, or crystal). Dynamic light scattering (DLS) was used to examine the cold-induced precipitation or gelation of two human cryoglobulins, namely, Pot IgM and Yvo IgM. The DLS assay was highly reproducible, sensitive, and had low intra-assay variations for both IgM cryoglobulins. Distinct processes were revealed to contribute to precipitation and gelation of cryoglobulins. The precipitation of Pot IgM displayed a rapid transition from solution to solid phases, with a wide distribution of aggregate sizes. In contrast, the gelation of Yvo IgM progressed gradually across a broad temperature range to produce a relatively uniform gel matrix. Initial cryoglobulin concentrations determined the kinetics and critical temperatures for both precipitation and gelation. Moreover, the Yvo IgM was observed to have a distinct relationship between concentrations and mean hydrodynamic diameters or particle sizes. Concentration-dependent effects on particle sizes were present, but not as pronounced for the Pot IgM. Precipitation and gelation of cryoglobulins were also found to be differentially responsive to changes in the aqueous environment. Our results indicate that DLS is a rapid, reliable, and sensitive method for characterizing the nature of disease-associated cryoglobulins. Copyright © 2007 John Wiley & Sons, Ltd. [source] Rituximab (B-cell depleting antibody) associated lung injury (RALI): A pediatric case and systematic review of the literaturePEDIATRIC PULMONOLOGY, Issue 9 2009Martin Bitzan MD Abstract Introduction Pulmonary toxicity of delayed onset is a rare complication of B-lymphocyte depleting antibody therapy and has been almost exclusively reported in older patients with B-cell malignancies. Aims To describe a pediatric patient with rituximab-associated lung injury (RALI), to systematically analyze previous reports of pulmonary complications, and to summarize common clinico-pathological features, treatment, and outcome. Results A teenage boy with focal segmental glomerulosclerosis (FSGS) presented with progressive dyspnea, fever, hypoxemia and fatigue 18 days after the completion of a second course of rituximab infusions for calcineurin inhibitor-dependent nephrotic syndrome. Respiratory symptoms started while he received high-dose prednisone for persistent proteinuria. Bilateral, diffuse ground-glass infiltrates corresponded to the presence of inflammatory cells in the bronchioalveolar lavage fluid. Empiric antibiotic treatment including clarithromycin was given, but the microbiological work-up remained negative. Serum IgE, C3, and C4 concentrations were normal. He recovered within 3 weeks after onset. We systematically reviewed 23 reports describing 30 additional cases of rituximab-associated lung disease. Twenty eight patients had received rituximab for B-cell malignancies, one for graft-versus-host disease and one for immune thrombocytopenia. Median age was 64 years (interquartile range [IQR] 58,69 years). Seventy one percent received concomitant chemotherapy. Time to onset from the last rituximab dose was 14 days (IQR 11,22 days). Eleven of 31 patients required mechanical ventilation, and 9 died (29%). Ventilation was a significant predictor of fatal outcome (odds ratio 46.7; confidence interval 9.5,229.9). High dose glucocorticoid therapy did not improve survival or prevent severe lung disease or death. Conclusions With the expanding use of rituximab for novel indications, additional cases of RALI affecting younger age groups are expected to emerge. Mechanical ventilation predicts poor outcome. Glucocorticoids may not be protective. Pediatr Pulmonol. 2009; 44:922,934. © 2009 Wiley-Liss, Inc. [source] Serum BLyS levels increase after rituximab as initial therapy in patients with follicular grade 1 non-Hodgkin lymphoma,AMERICAN JOURNAL OF HEMATOLOGY, Issue 2 2009Stephen M. Ansell Serum B-lymphocyte stimulator (BLyS) levels are elevated in a subset of non-Hodgkin lymphoma (NHL) patients, particularly those with a family history of B-cell malignancies or a polymorphism in the BLyS gene. BLyS promotes growth of malignant B-cells and increased serum BLyS levels are associated with a poor clinical outcome. In this study, BLyS levels were measured before and after 4 weekly doses of rituximab in 30 patients with previously untreated follicular Grade 1 NHL. A significant increase was seen in the serum levels of BLyS (P = 0.0001) after rituximab therapy. The increase was independent of genetic variability in the BLyS gene. Am. J. Hematol., 2009. © 2008 Wiley-Liss, Inc. [source] Application of combined immunofluorescence and fluorescence in situ hybridization on paraffin-embedded sections to characterize T-cell lymphoma with EBV-infected B-cell blastsGENES, CHROMOSOMES AND CANCER, Issue 4 2004Genevieve K. Temple Combined immunofluorescence (IF) and fluorescence in situ hybridization (FISH) on formalin-fixed, paraffin-embedded tissue sections were used to examine lymph node tissue from two patients diagnosed with T-cell lymphoma with Epstein,Barr virus (EBV),infected B-cell blasts. The majority of cells within the samples comprised T-cells staining positively for CD3. In addition, both patients had a population of large pleiomorphic cells that were positive for the B-cell marker CD20 and for EBV LMP-1. Standard PCR clonality testing of the nodes revealed both immunoglobulin heavy chain (IGH) and T-cell receptor (TCR) clonal rearrangements in one patient, although in the other case monoclonality was demonstrated only for TCRG. Cytogenetics of cultured lymphocytes from nodal tissue revealed two apparently unrelated abnormal clones in both patients. Combined IF and FISH revealed that these phenomena reflected two abnormal populations of B- and T-cells rather than reactive B-cell hyperplasia or biphenotypic evolution from a common ancestral lymphoma. True B-cell malignancy probably emerged within a preexisting but unrelated T-cell lymphoma. This is the first study to relate the phenotype of the abnormal cells in such cases to specific clonal populations of cells, and it demonstrates a method that may easily be introduced into a diagnostic cytogenetics laboratory with access to standard pathology laboratory resources. © 2004 Wiley-Liss, Inc. [source] TCL1 is activated by chromosomal rearrangement or by hypomethylationGENES, CHROMOSOMES AND CANCER, Issue 4 2001Martin R. Yuille TCL1 is an oncogene activated by recurrent reciprocal translocations at chromosome segment 14q32.1 in the most common of the mature T-cell malignancies, T-cell prolymphocytic leukemia. It acts to transport Akt1 to the nucleus and enhance Akt1's serine-threonine kinase activity. TCL1 is also expressed in the B-cell malignancy, Burkitt's lymphoma (BL). However, 14q32.1 breakpoints have not been detected in BL, and we therefore investigated in more detail how expression was activated. No evidence for rearrangement near TCL1 was found in BL. Instead, a NotI site adjacent to the TATA box in the TCL1 promoter was found to be unmethylated. By contrast, tumor cell lines not expressing TCL1 were fully methylated at this NotI site, while normal somatic cells were hemimethylated. We also found that TCL1 was expressed in B-cell chronic lymphocytic leukemia (CLL) and the related disorder splenic lymphoma with villous lymphocytes (unlike in normal mature B-cells), and that the NotI site was unmethylated on both alleles. This correlation of repression and methylation was tested in vitro. When cells with both alleles methylated at the NotI site were demethylated, TCL1 expression was induced. These data provide evidence that in mature B-cell malignancies there is an alternative mechanism of TCL1 activation that apparently involves loss of methylation of one promoter allele. We discuss the significance of this for CLL tumorigenesis and for genomewide hypomethylation in CLL. © 2001 Wiley-Liss, Inc. [source] Expression of regulatory genes for lymphoplasmacytic cell differentiation in Waldenstrom MacroglobulinemiaBRITISH JOURNAL OF HAEMATOLOGY, Issue 1 2009Xavier Leleu Summary Waldenstrom Macroglobulinemia (WM) is a B-cell malignancy characterized by excess bone marrow (BM) lymphoplasmacytic cells (LPC). The accumulation of LPC in WM may represent a failure of B-cells to properly differentiate into plasma cells. The present study investigated transcriptional expression of genes involved in late B-cell differentiation, including PRDM1, PAX5, XBP1 transcripts and ERN1, in BM B-cells from 31 patients with WM and six healthy donors. Real time reverse transcription polymerase chain reaction (RT-PCR) determined that approximately 80% of the patients had high XBP1 spliced mRNA expression, 80% of whom had high mRNA ERN1, expression. XBP1, PRDM1 and PAX5 mRNA was present in all patients studied. Using relative quantitative RT-PCR we isolated two groups with low and high expression of XBP1, XBP1 spliced and ERN1,. Sequence analysis showed germline polymorphisms in all genes studied. These data depict for the first time a heterogeneous expression pattern of the genes involved in late differentiation process of plasma cells in patients with WM and propose a role of XBP1-ERN1, in WM pathogenesis. [source] Cantharidin induces apoptosis of human multiple myeloma cells via inhibition of the JAK/STAT pathwayCANCER SCIENCE, Issue 9 2008Morihiko Sagawa Multiple myeloma is an incurable B-cell malignancy requiring new therapeutic strategies in clinical settings. Interleukin (IL),6 signaling pathways play a critical role in the pathogenesis of multiple myeloma. The traditional Chinese medicine cantharidin (CTD) has been shown to inhibit cellular proliferation and induce apoptosis of various cancer cells. The aim of this study was to investigate the possibility of CTD as a novel therapeutic agent for the patients with multiple myeloma. We investigated the in vitro effects of CTD for its antimyeloma activity, and further examined the molecular mechanisms of CTD-induced apoptosis. CTD inhibited the cellular growth of human myeloma cell lines as well as freshly isolated myeloma cells in patients. Cultivation with CTD induced apoptosis of myeloma cells in a cell-cycle-independent manner. Treatment with CTD induced caspase-3, ,8, and ,9 activities, and it was completely blocked by each caspase inhibitor. We further examined the effect of CTD on the IL-6 signaling pathway in myeloma cells, and found that CTD inhibited phosphorylation of STAT3 at tyrosine 705 residue as early as 1 h after treatment and down-regulated the expression of the antiapoptotic bcl-xL protein. STAT3 directly bound and activated the transcription of bcl-xL gene promoter, resulting in the induction of the expression of bcl-xL in myeloma cells. The essential role of STAT3 in CTD effects was confirmed by transfection with the constitutively active and dominant negative form of STAT3 in U266 cells. In conclusion, we have demonstrated that CTD is a promising candidate to be a new therapeutic agent in signal transduction therapy. (Cancer Sci 2008; 99: 1820,1826) [source] | ||||||||||||||||||||||