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Haruhiko Ohashi

Publications and source records attributed to Haruhiko Ohashi.

4 recordsLinked to original sources

Case of Epstein-Barr virus-associated transformation of mantle cell lymphoma.

We report here a case of mantle cell lymphoma (MCL) in a patient who, following Epstein-Barr virus (EBV) infection, developed diffuse large B-cell lymphoma (DLBCL). A 47-year-old woman was diagnosed as having MCL with clinical stage IIIA in July 1990. After treatment with a third-generation chemotherapy without response, she was kept under observation for 8 years. In January 1999, fever and night sweats appeared with laboratory evidence for EBV infection, and acute swelling of lymph nodes and hepatosplenomegaly developed in May 1999. Histopathological examination confirmed the diagnosis of DLBCL. Sequence analysis of the complementarity-determining region (CDR)-III of the immunoglobulin heavy chain gene demonstrated clonal identity between the initial MCL and the subsequent DLBCL. Immunohistochemistry revealed that cyclin D1, CD5, and CD20 were expressed in the MCL but lost in the DLBCL cells, and EBER-ISH confirmed that EBV infection was absent in the former but present in the latter. Southern hybridization with the EBV terminal repeat probe showed a clear monoclonal pattern in the DLBCL specimen. All these results suggest that EBV infection may have been the molecular event that caused transformation of MCL cell(s) to DLBCL in this case. This is, to the best of our knowledge, the first well-documented case of EBV-associated transformation of MCL.

Antigens, CD↗

Failure to detect Epstein-Barr virus (EBV) DNA in plasma by real-time PCR in a case of EBV-associated posttransplantation lymphoproliferative disorder confined to the central nervous system.

We report here a patient who developed multiple central nervous system (CNS) space-occupying lesions 6 months after bone marrow transplantation from an HLA-matched unrelated donor. He had extensive chronic graft-versus-host disease and severe thrombocytopenia. Posttransplantation lymphoproliferative disorder (PTLD) was diagnosed after biopsy of the lesion was facilitated by the transfusion of 40 units of platelets. Epstein-Barr virus (EBV) DNA was not initially detected in the peripheral blood by real-time polymerase chain reaction, and the blood became positive for EBV at a low level only after more than 6 weeks had passed since the initial identification of detectable intracranial lesions. The patient died of cerebral herniation while donor leukocyte infusion was being prepared, and an autopsy confirmed the diagnosis of EBV-associated PTLD restricted to the CNS.

Adult↗

The MAGE-A1 gene expression is not determined solely by methylation status of the promoter region in hematological malignancies.

Tumor antigens such as MAGE-A1 are aberrantly expressed in many human tumors and could be recognized by CTL. Thus, they could be targets for cancer immunotherapy. It is presently considered that the expression of the MAGE-A1 gene is regulated by methylation of its promoter region. To estimate the possibility of activating the MAGE-A1 gene with demethylating agents with a view toward clinical use, we assessed the methylation status of its CpG-rich promoter by sodium bisulfite mapping both of samples that express the gene and those that do not. Cell lines and samples from patients with hematological malignancies were examined. Surprisingly, the methylation status of the MAGE-A1 gene did not clearly correlate with the expression of the gene. Our results indicate that the MAGE-A1 gene expression is not determined solely by the methylation status of the promoter region in hematological malignancies.

Antigens, Neoplasm↗