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Motoko Yamaguchi

Publications and source records attributed to Motoko Yamaguchi.

26 records · Page 2Linked to original sources
PubMed2004

[Diffuse large B-cell lymphoma of the knee occurring 70 years after tuberculous arthritis].

A 72-year-old woman presented with a progressive swollen and painful left knee over a period of a month. The patient had a history of tuberculous arthritis of the left knee joint at the age of 1-2 years. Since then the knee showed a deformity and contraction. MRI scan demonstrated a soft tissue tumor measuring 7 x 8 x 6 cm in the front of the knee, a biopsy specimen taken from which revealed large B-cell lymphoma. The tumor cells showed a phenotype of CD3- CD5- CD10- CD20+ CD21- BCL2+, and surface immunoglobulin M-kappa. Since the lymphoma cells were found to be negative for Epstein-Barr virus encoded RNA by means of in situ hybridization, the DLBCL in this patient was thought to be caused by a different mechanism from pyothorax-associated lymphoma. The patient was treated with chemotherapy (CHOP) followed by radiotherapy, and obtained partial remission. There is no evidence of progression seven months after diagnosis.

Aged↗
PubMed2003

Microarray reveals differences in both tumors and vascular specific gene expression in de novo CD5+ and CD5- diffuse large B-cell lymphomas.

Malignant lymphoma is a heterogeneous disease with different clinical features. Among diffuse large B-cell lymphomas (DLBCLs), a unique subtype has been identified recently based on cell surface marker CD5 and clinicopathological features. These de novo CD5(+) DLBCLs account for approximately 10% of all of the DLBCLs and have poorer prognosis. To additionally understand this subtype of DLBCLs at the molecular level and to find genes that are differentially expressed in de novo CD5(+) DLBCLs, CD5(-) DLBCLs, and mantle cell lymphomas, which also have poor prognosis, we performed gene expression profiling using cDNA microarray technology. Data from a total of 9 samples of CD5(-) DLBCLs, 11 samples of de novo CD5(+) DLBCLs, and 10 samples of mantle cell lymphomas were acquired. A series of genes were identified that distinguish these three types of lymphomas. Among DLBCL cases, integrin beta1 and/or CD36 adhesion molecules were overexpressed in most cases of CD5(+) DLBCL. An immunohistochemical confirmation study revealed that integrin beta1 was expressed on lymphoma cells, which may account for the high extranodal involvement and poor prognosis of CD5(+) DLBCLs. In contrast, CD36 was overexpressed on vascular endothelia in CD5(+) DLBCLs, although there was no difference in vascularity detected by von Wilbrand factor antibody between CD5(+) and CD5(-) DLBCLs. Those results suggest that CD5(+) and CD5(-) DLBCLs have different gene expression signatures in both tumor cells and their vascular systems.

Aged↗
PubMed2003

Hypermethylation of death-associated protein (DAP) kinase CpG island is frequent not only in B-cell but also in T- and natural killer (NK)/T-cell malignancies.

Death-associated protein (DAP) kinase is a pro-apoptotic serine/threonine kinase with a death domain, which is involved in apoptosis induced by interferon-gamma, tumor necrosis factor-alpha, and Fas ligand. Down-regulation of DAP kinase gene expression by hypermethylation of its promoter region might result in resistance to apoptotic cell death, and could provide a basis for tumor development. In the present study, we employed methylation-specific polymerase chain reaction to examine the methylation status of CpG islands in the DAP kinase gene in 19 cases of T-cell malignancies (including eight adult T-cell leukemia/lymphoma), 24 of natural killer (NK)/T-cell, and 34 of B-cell. Frequency of methylation was significantly higher in B-cell (27 of 34, 79.4%) than in T-cell malignancies (nine of 19, 47.4%) (P<0.05). Fifteen of 24 (62.5%) NK/T-cell lymphomas showed DNA methylation. One B-cell lymphoma cell line with DNA methylation was resistant to apoptotic stimuli, and treatment of the cells with a demethylating agent restored apoptotic cell death. These findings suggested that suppression of DAP kinase expression by DNA methylation might play a substantial role in the development of not only B-cell, but also T- and NK/T-cell lymphomas.

Antibodies, Monoclonal↗
PubMed2002

De novo CD5+ diffuse large B-cell lymphoma: a clinicopathologic study of 109 patients.

De novo CD5+ diffuse large B-cell lymphoma (CD5+ DLBCL) is known to have phenotypically and genotypically different characteristics than CD5- DLBCL and mantle cell lymphoma (MCL). To further characterize CD5+ DLBCL, 109 patients with CD5+ DLBCL were reviewed, and the results were compared with those of 384 CD5- DLBCL and 128 cyclin D1+ MCL patients. Patients with CD5+ DLBCL showed a higher age distribution (median, 66 years; P =.0083) and a female predominance (male-female ratio, 49:60, P =.011) compared with those with CD5- DLBCL. CD5+ DLBCL was more closely associated with many aggressive clinical features or parameters than CD5- DLBCL: 69% older than 60 years (P =.039), 34% with performance status greater than 1 (P =.0016), 69% with serum lactate dehydrogenase level higher than normal (P <.0001), 62% with stage III/IV disease at diagnosis (P =.0023), 35% with more than one extranodal site (P =.023), and 40% with B symptoms (P =.0031). The overall International Prognostic Index score was thus significantly higher for the patients with CD5+ DLBCL than for those with CD5- DLBCL (P =.00005). The most frequent site of extranodal involvement was bone marrow (28%), a higher frequency than that for CD5- DLBCL (P <.0001) but lower than that for cyclin D1+ MCL (P =.0015). Histopathologically, CD5+ DLBCL showed centroblastic morphology except for 3 patients with immunoblastic disease, and interfollicular growth pattern (7%) and intravascular or intrasinusoidal infiltration (19%) were observed. Immunophenotypically, CD5+ DLBCL was characterized by a CD5+CD10-CD19+CD20+CD21-CD23- cyclin D1- phenotype and a predominance of surface IgMkappa. Of particular interest is that CD5+ DLBCL was characterized by a survival curve significantly inferior to that for patients with CD5- DLBCL (P =.0026). These findings suggest that CD5+ DLBCL may constitute a unique subgroup of DLBCL.

Adolescent↗
PubMed2002

MUM1/IRF4 expression is an unfavorable prognostic factor in B-cell chronic lymphocytic leukemia (CLL)/small lymphocytic lymphoma (SLL).

B-Cell chronic lymphocytic leukemia (B-CLL) / small lymphocytic lymphoma (SLL) consists of heterogeneous diseases that are distinguished by morphological, immunophenotypic and molecular features. MUM1 (multiple myeloma oncogene 1) is a protooncogene that is deregulated as a result of (6;14)(p25;q32) chromosomal translocation in multiple myeloma, and is also expressed in a variety of malignant lymphoma entities. We examined the expression of MUM1 in B-CLL / SLL, and found that 2 of 4 B-CLL-derived cell lines and 14 of 29 patients' specimens expressed MUM1 by immunohistochemical analysis. MUM1 expression was not associated with CD38 expression, somatic hypermutation of immunoglobulin heavy chain gene variable region (IgV(H)), or any other clinical characteristics of the patients. Interestingly, the patients who were positive for MUM1 showed shorter overall survival times than those who were negative for MUM1 (50% survival: 22 months vs. 82 months) (P = 0.0008, log-rank test). Multivariate analysis by Cox's proportional-hazards regression model showed that MUM1 expression and unmutated IgV(H) status were independent unfavorable prognostic factors in patients with B-CLL / SLL. These findings suggest that MUM1 expression is a useful prognostic factor in B-CLL / SLL. The biological role and mechanism of action of MUM1 in B-CLL / SLL need to be clarified for the development of therapies for patients with the poor prognostic subtype.

ADP-ribosyl Cyclase↗