Adult T-cell leukemia/lymphoma in which the pathohistological diagnosis was identical to that of Ki-1 positive anaplastic large cell lymphoma

Primary and isolated adult T-cell leukemia/lymphoma of the bone marrow

The distribution of adult T-cell leukemia/lymphoma (ATLL) is typically systemic. In addition to peripheral blood (PB) and lymph nodes, extranodal sites such as the skin, lung, liver, gastrointestinal tract, and central nervous system are frequently involved. We report a unique case of ATLL in which the patient presented with prolonged fever. A 65-year-old man had high-grade fever lasting for 2 weeks. He showed no lymphadenopathy, hepatosplenomegaly, skin lesions, or PB involvement. Bone marrow examination showed widespread infiltration of ATLL cells. (18)F-fluorodeoxy glucose positron emission tomography (FDG-PET) revealed that the disease was confined to the bone marrow.

Susceptibility of human T-cell leukemia virus type I-infected cells to humanized anti-CD30 monoclonal antibodies in vitro and in vivo

Adult T-cell leukemia (ATL) is an aggressive malignancy of activated CD4(+) T cells associated with human T-cell leukemia virus type I (HTLV-I) infection. No conventional chemotherapy regimen has appeared successful in patients with ATL, thus establishing effective therapy is urgently required. In some cases, ATL tumor cells express CD30 on the cell surface, therefore, a therapy with mAb against CD30 would be beneficial. To investigate the effect of CD30-mediated therapy on ATL, we assessed SGN-30, a chimeric anti-CD30 mAb, and SGN-35, a monomethyl auristatin E-conjugated anti-CD30 mAb, in vitro and in vivo. Three HTLV-I-infected cell lines were co-cultured with SGN-30 or SGN-35, and the growth-inhibitory effects on the HTLV-I-infected cells were evaluated using an in vitro cell proliferation assay and cell cycle analysis. SGN-30 and SGN-35 showed growth-inhibitory activity against the HTLV-I-infected cell lines by apoptosis and/or cell growth arrest in vitro. To further investigate the effects of SGN-30 and SGN-35 on HTLV-I-infected cells in vivo, we used NOD/SCID mice subcutaneously engrafted with HTLV-I-infected cells. Both mAbs significantly inhibited the growth of HTLV-I-infected cell tumors in the NOD/SCID murine xenograft models. These data suggest that CD30-mediated therapy with SGN-30 or SGN-35 would be useful for patients with ATL.

Marek's disease is a natural model for lymphomas overexpressing Hodgkin's disease antigen (CD30)

Animal models are essential for elucidating the molecular mechanisms of carcinogenesis. Hodgkin's and many diverse non-Hodgkin's lymphomas overexpress the Hodgkin's disease antigen CD30 (CD30(hi)), a tumor necrosis factor receptor II family member. Here we show that chicken Marek's disease (MD) lymphoma cells are also CD30(hi) and are a unique natural model for CD30(hi) lymphoma. Chicken CD30 resembles an ancestral form, and we identify a previously undescribed potential cytoplasmic signaling domain conserved in chicken, human, and mouse CD30. Our phylogeneic analysis defines a relationship between the structures of human and mouse CD30 and confirms that mouse CD30 represents the ancestral mammalian gene structure. CD30 expression by MD virus (MDV)-transformed lymphocytes correlates with expression of the MDV Meq putative oncogene (a c-Jun homologue) in vivo. The chicken CD30 promoter has 15 predicted high-stringency Meq-binding transcription factor recognition motifs, and Meq enhances transcription from the CD30 promoter in vitro. Plasma proteomics identified a soluble form of CD30. CD30 overexpression is evolutionarily conserved and defines one class of neoplastic transformation events, regardless of etiology. We propose that CD30 is a component of a critical intracellular signaling pathway perturbed in neoplastic transformation. Specific anti-CD30 Igs occurred after infection of genetically MD-resistant chickens with oncogenic MDV, suggesting immunity to CD30 could play a role in MD lymphoma regression.