One in 20 carriers of human T-cell leukemia virus type 1 (HTLV-1) will develop adult T-cell leukemia/lymphoma (ATL), a disease frequently associated with hypercalcemia, bone destruction, and a fatal course refractory to current therapies. Overexpression of the HTLV-1-encoded Tax oncoprotein under the human granzyme B promoter causes large granular lymphocytic leukemia/lymphomas in mice. We foun...

To evaluate the relationships between human T lymphotropic virus type I (HTLV-I) and hepatitis virus type B (HBV) infections, we compared both individual and geographical distributions of carriers of HTLV-I and HBV, and antibody positives to HBV in two ATL-endemic islands in Kyushu, Japan. The positive rates of antibodies to HTLV-I (anti-HTLV-I-Ab) in sera among healthy inhabitants older than 3...

Mathematical analysis is carried out that completely determines the global dynamics of a mathematical model for the transmission of human T-cell lymphotropic virus I (HTLV-I) infection and the development of adult T-cell leukemia (ATL). HTLV-I infection of healthy CD4þ T cells takes place through cell-to-cell contact with infected T cells. The infected T cells can remain latent and harbor virus...

Human T-cell leukemia virus type 1 (HTLV-1) causes adult T-cell leukemia-lymphoma (ATL) and inflammatory diseases in a small percentage of infected individuals. Host immune responses, in particular cytotoxic T lymphocytes (CTLs), influence the proliferation and survival of ATL cells and HTLV-1-infected cells. We generated recombinant vaccinia viruses (rVVs) expressing HTLV-1 basic leucine zippe...

Human T-cell leukemia virus type 1 (HTLV-1) is the etiological agent of adult T-cell leukemia (ATL), and the viral oncoprotein Tax plays key roles in the immortalization of human T cells, lifelong persistent infection, and leukemogenesis. We herein identify the ubiquitin-specific protease 10 (USP10) as a Tax-interactor in HTLV-1-infected T cells. USP10 is an antistress factor against various en...

The study of tumor viruses paves the way for understanding the mechanisms of virus pathogenesis, including those involved in establishing infection and dissemination in the host tumor affecting immune-compromised patients. The processes ranging from viral infection to progressing malignancy are slow and usually insufficient for establishment of transformed cells that develop cancer in only a mi...

Adult T-cell leukemia (ATL) is a malignant tumor of human CD4(+) T cells infected with a human retrovirus, T lymphotropic virus type-1 (HTLV-1). The aim of the present study was to investigate the apoptotic effects of phenoxazines, 2-amino-4,4alpha-dihydro-4alpha,7-dimethyl-3H-phenoxazine-3-one (Phx-1), 3-amino-1,4alpha-dihydro-4alpha,8-dimethyl-2H-phenoxazine-2-one (Phx-2), and 2-aminophenoxaz...

Retroviral infection is associated with a number of pathologic abnormalities, including a variety of cancers, immunologic diseases, and neurologic disorders. Shortly after its discovery in 1980, human T cell leukemia virus type I (HTLV-I) was found to be the etiologic agent of both adult T cell leukemia (ATL) and HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP), a neurologic ...

Adult T-cell leukemia (ATL) is a malignancy of mature lymphocytes caused by the retrovirus human T-cell lymphotrophic virus-I (HTLV-I). It is an aggressive leukemia with an overall mortality rate of 50% within 5 months; no conventional chemotherapy regimen appears successful in inducing long-term disease-free survival in ATL patients. However, ATL cells constitutively express high-affinity inte...

Human T-cell leukemia virus type I (HTLV-I) is a causative agent of adult T-cell leukemia (ATL). To elucidate the role of HTLV-I in leukemogenesis, we examined the biological activity of a defective HTLV-I provirus with the env-pX 3' long terminal repeat region cloned from leukemic cells of an ATL patient. Transfection experiments showed growth stimulation of NIH 3T3 cells--growing beyond the s...