Human T cell leukemia virus type 1 (HTLV-1) is the etiological agent of adult T cell leukemia/lymphoma (ATLL) and several inflammatory diseases. Tax, the protein encoded by HTLV-1, may be responsible for the development of the diseases caused by this virus. To investigate the pathogenic role of Tax, several transgenic mouse strains expressing Tax have been developed in recent years. These mice ...

The current World Health Organization (WHO) classification of hematopoietic malignancies defines several types of mature T-cell leukemia including T-cell prolymphocytic leukemia (T-PLL), Sezary syndrome (SS), and T-cell large granular lymphocytic (T-LGL) leukemia. These neoplasms can show overlapping features with each other and with T-cell lymphomas involving peripheral blood (PB). We analyzed...

Out of 153 newly referred human T-lymphotropic virus type I infected patients, 42 (27%) had 5% or more abnormal lymphocytes, consistent with the diagnosis of smoldering adult T-cell leukemia/lymphoma. The abnormal lymphocyte percentage was higher in patients with human T-lymphotropic virus type I associated inflammatory disease compared with asymptomatic carriers (P=0.006). Over 4.5 years media...

Adult T-cell leukemia/lymphoma (ATL) is a malignancy of mature CD4+ T-cells caused by human T-cell lymphotropic virus type 1 (HTLV-1). Twenty million people are believed to be infected throughout the world, mostly in Japan, Africa, the Caribbean, and South America, particularly in Brazil and Peru. ATL affects about 5% of infected individuals and is classified in the following clinical forms: ac...

Adult T-cell leukemia-lymphoma (ATL) was first described in 1977 as a distinct clinico-pathological entity with a suspected viral etiology. Subsequently, a novel RNA retrovirus, human T-cell leukemia/lymphotropic virus type 1 (HTLV-1) was isolated from a cell line established from the leukemic cells of an ATL patient, and the finding of a clear association with ATL led to its inclusion among hu...

Although extensive clinical data have established that the loss of Ikaros tumor suppressor activity via genetic inactivation is a major contributor to leukemogenesis leading to B-cell ALL, less is known about the role of Ikaros in T-cell leukemia. The T-cell malignancies observed in Ikaros-deficient mice suggest that Ikaros is likely to function as a tumor suppressor in T-cells. In human, multi...

Adult T-cell leukemia/lymphoma is a rare malignancy associated with the human retrovirus human T-cell lymphotropic virus type 1. It is characterized by the proliferation of highly pleomorphic lymphocytes. Involvement of peripheral blood, bone marrow, lymph nodes, spleen, and extranodal sites such as skin, liver, gastrointestinal tract, and central nervous system can occur. There are four distin...

Adult T-cell lymphoma/leukemia (ATL) is a rare T-cell lymphoproliferative neoplasm caused by human T-lymphotrophic virus 1. In its more common, aggressive forms, ATL carries one of the poorest prognoses of the non-Hodgkin lymphomas. The disease has clinical subtypes (ie, acute, lymphoma, chronic, and smoldering forms) defined by the presenting features, and therefore, the clinical course can va...