Adult T-cell leukemia (ATL) occurs in a small population of human T-cell leukemia virus type 1 (HTLV-1)-infected individuals. Although the critical risk factor for ATL development is not clear, it has been noted that ATL is incidentally associated with mother-to-child infection, elevated proviral loads, and weakness in HTLV-1-specific T-cell immune responses. In the present study, using a rat s...

Human T-cell leukemia virus type 1 (HTLV-1) infection causes adult T-cell leukemia (ATL), which is frequently resistant to currently available therapies and has a very poor prognosis. To prevent the development of ATL among carriers, it is important to control HTLV-1-infected cells in infected individuals. Therefore, the establishment of novel therapies with drugs specifically targeting infecte...

Human T-cell leukemia virus type I (HTLV-I) is recognized as the etiologic agent of adult T-cell leukemia (ATL), a disease endemic in certain regions of southeastern Japan, Africa, and the Caribbean basin. Although HTLV-I can immortalize T lymphocytes in culture, factors leading to tumor progression after HTLV-I infection remain elusive. Previous attempts to propagate the ATL tumor cells in ani...

In this issue of ONCOLOGY, Tobinai reviews the management of human T-cell lymphotropic virus type 1 (HTLV-1)–associated adult T-cell leukemia/lymphoma (ATL). Although rare in the United States, an estimated 10 to 20 million people are infected with HTLV-1 worldwide and 2% to 5% will develop ATL.[1] The prevalence of HTLV-1 infection and the consequent poor prognosis of ATL mark the disease as a...

conclusions we observed upper limit values of the normal range for mg in the atl cases which may not be neglected from a clinical point of view. the other measurements did not show a remarkable difference with normal levels. introduction adult t‐cell leukemia (atl) is a rare neoplasm of post-thymic lymphocytes observed in only 3% - 4% of patients infected with human t-lymphotropic virus (htlv-1...

Adult T-cell leukemia-lymphoma (ATL) is a distinct malignancy of regulatory T cell (Treg)/TH2 cells caused by human T-cell lymphotropic virus type I (HTLV-1), with a high frequency of expression of CD3/CD4/CD25/CCR4 and FoxP3 in about half of the cells. However, in primary ATL cells, although expression of the virus, including the Tax oncoprotein, appears just after an in vitro culture, integra...

Adult T-cell leukemia (ATL) caused by human T-cell leukemia virus type I (HTLV-I) is characterized by poor prognosis after chemotherapy. Recent clinical trials have indicated, however, that allogeneic but not autologous hematopoietic stem cell transplantation (HSCT) for ATL can yield better clinical outcomes. In the present study, we investigated cellular immune responses of ATL patients who ob...

Adult T-cell leukemia-lymphoma (ATL) is a unique T-cell cancer first described in Japan. We estimate that more than 200 patients a year have been detected in Kyushu. The surface phenotype of ATL cells characterized by monoclonal antibodies is T3+, T4+, T8-, T11+, and Tac+. In all cases the serum is positive for anti-human T-cell leukemia (lymphotropic) virus (HTLV-I) antibodies and the ATL cell...

Purpose: Indoleamine 2,3-dioxygenase 1 (IDO1: IDO), an enzyme catabolizing tryptophan (Trp) into the kynurenine (Kyn) pathway, is increasingly being recognized as an important microenvironmental factor suppressing antitumor immune responses. The purpose of the present study was to determine the prognostic significance of Trp catabolism in adult T-cell leukemia/lymphoma (ATL). Experimental Desig...

Adult T cell leukemia (ATL) is associated with human T cell leukemia virus type 1 (HTLV-1) infection, and almost all ATL patients have the complication of hypercalcemia. To understand the mechanism of the high incidence of hypercalcemia in ATL, we studied the expression of a parathyroid hormone-related protein (PTHrP) gene that has been proposed as a causative factor of hypercalcemia in some so...