Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0079731 (B-cell lymphoma)
 16,671 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

L-PHA reactive oligosaccharides are found on the surface of HBL-2 cells, a lymphoma cell line, established from a human diffuse large B cell lymphoma (DLBCL). Swainsonine (SW) is a potent inhibitor of alpha-mannosidase II which catalyzes the biosynthesis of complex type N-linked oligosaccharides in human cells. CD40L stimulation of HBL-2 cells leads to their prolonged survival. Reduction in the expression of N-linked oligosaccharides, including L-PHA reactive oligosaccharides, on the cell surface by SW treatment resulted in enhancement of HBL-2 cell survival by CD40L stimulation. From an Annexin V assay the enhancement of CD40L-mediated HBL-2 cell survival by SW treatment may have resulted from anti-necrotic effects after 48 h of incubation. Bcl-2 enzyme linked immuno sorbent assay (ELISA) data showed that the expression of bcl-2 protein was enhanced by CD40L stimulation alone and also by CD40L stimulation along with SW treatment. However, there were no significant differences in the amount of bcl-2 protein with these treatments. Therefore, the enhancement of CD40L-mediated cell survival by SW treatment did not depend on the enhancement of bcl-2 protein expression. Furthermore, SW treatment of HBL-2 cells led to degradation of the heavy chain of IgM and rescued HBL-2 cells from anti-IgM-induced growth inhibition. Anti-IgM induced growth inhibition of HBL-2 cells prevented the inhibition of cell death by CD40L. From the present results it is possible that reduction of N-glycosylation of the heavy chain of IgM by SW treatment may reduce anti-IgM-induced growth inhibition, and reduction in anti-IgM-induced growth inhibition due to altered N-glycosylation may enhance CD40-CD40L-mediated cell survival through TRAF2 which interacts with both IgM and CD40 in HBL-2 cells.
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PMID:Regulatory roles of N-glycosylation of immunoglobulin M in CD40-CD40L-mediated cell survival of human diffuse large B cell lymphoma. 1506 43

Beta1-6 branching of L-PHA reactive oligosaccharides, one of the N-glycan structures, plays an important role in the biological behavior of various tumor cell lines. We reported previously that the expression of L-PHA reactive oligosaccharides was closely associated with the prognosis of patients with human diffuse large B cell lymphoma (DLBCL). In the present study, by Western blotting, we analyzed the N-glycosylation patterns in CD45 having L-PHA reactive oligosaccharides. In two cases of DLBCL which do and do not express non-sialylated L-PHA reactive oligosaccharides CD45 was found to be about 180-210 kDa and 180-200 kDa, respectively. Furthermore, after endoglycosidase F3 treatment the CD45 in both cases was found to be 190 or 160 kDa. Therefore, the differences in CD45 molecular weight between the two cases is due to differences in the amount of N-glycosylation. To clarify the biological functions of CD45 N-glycans in DLBCL, we analyzed the antiproliferative effects on human lymphoma cells of bovine galectin-1 (beta-galactoside-binding lectin-1), which reacts with CD45 N-glycans. Bovine galectin-1 stimulation of the DLBCL cell line HBL-2 resulted in inhibition of its growth in vitro. Swainsonine (SW) is a potent inhibitor of alpha-mannosidase II, which catalyzes the synthesis of complex type N-linked oligosaccharides. Reduction in expression of N-linked oligosaccharides, including L-PHA reactive oligosaccharides, on the cell surface by SW treatment prevented the growth inhibition of HBL-2 cells by galectin-1. On Western blots one 190 kDa isoform of the three CD45 isoforms which have N-linked oligosaccharide ligands for galectin-1, was detected with a reduction in molecular weight of about 5 kDa after SW treatment. These data suggested that the amount of CD45 N-glycans is reduced by SW treatment, and that this reduction of N-glycans prevents the interaction between CD45 and galectin-1. Alteration in N-glycosylation of CD45 may regulate lymphoma cell growth in DLBCL through the interaction between the N-glycans of CD45 and galectin-1.
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PMID:Altered N-glycosylation in CD45 and regulatory roles of altered N-glycosylation in galectin-1-induced growth inhibition in human diffuse large B cell lymphoma. 1558 10

To clarify the functions of CD45 N- and O-glycans in diffuse large B cell lymphoma (DLBCL), we analyzed the antiproliferative effects of bovine galectin-1 (beta-galactoside-binding lectin-1), which reacts with CD45 N-glycans and O-glycans, on human lymphoma cells. Bovine galectin-1 induced cell death of the DLBCL cell line HBL-2 in vitro. Swainsonine (SW) is a potent inhibitor of alpha-mannosidase II which catalyzes the synthesis of complex type N-linked oligosaccharides, and benzyl-GalNAc (BZGalNAc) is a potent inhibitor of O-glycosylation. Treatment with SW or BZGalNAc prevented cell death of HBL-2 cells by galectin-1. Western blot analysis revealed SW treatment reduced the molecular weight by about 5 kDa of one isoform at 190 kDa among three isoforms of CD45 which have N-linked oligosaccharide ligands for galectin-1. BZGalNAc treatment reduced the molecular weight of another isoform by about 15 kDa. These data suggest that the amount of CD45 N-glycans or O-glycans was reduced by SW and BZGalNAc treatment, respectively, and that reduction of CD45 N-glycans or O-glycans may prevent the interaction between CD45 and galectin-1. Alteration in CD45 N-glycans or O-glycans may regulate cell death of lymphoma cells through the interaction between CD45 N-glycans or O-glycans and galectin-1 in DLBCL.
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PMID:Regulatory roles of altered N- and O-glycosylation of CD45 in galectin-1-induced cell death in human diffuse large B cell lymphoma. 1575 3

Galectin-3 is a soluble endogenous lectin in vertebrates and is implicated in a variety of biological functions, including tumor cell adhesion, proliferation, differentiation, apoptosis, cancer progression and metastasis. In the present study, we analyzed the role of galectin-3 in apoptosis in human malignant lymphoma. Galectin-3 induced cell death in the HBL-2 human diffuse large B cell lymphoma cell line. A morphological examination and annexin V assays revealed that galectin-3-induced cell death is consistent with apoptosis and swainsonine, a potent inhibitor of alpha-mannosidase II, which catalyzes the synthesis of complex type N-linked oligosaccharides, inhibited galectin-3-induced apoptosis in HBL-2 cells. These results suggest that galectin-3 induces apoptosis in HBL-2 cells by interacting with cell surface N-linked oligosaccharides. Furthermore, treatment of cells with Vibrio Cholerae neuraminidase enhanced galectin-3-induced apoptosis, suggesting that cell surface sialylation regulates galectin-3-induced apoptosis in human B cell lymphoma. In conclusion, our results indicate that galectin-3-induced apoptosis is regulated by cell surface expression of N-glycans and sialic acid in human diffuse large B cell lymphoma. This mechanism may be involved in the malignant behavior of human lymphoma cells.
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PMID:Cell surface N-glycosylation and sialylation regulate galectin-3-induced apoptosis in human diffuse large B cell lymphoma. 1828 10