Identification of Genes Associated with the Progression of Adult T Cell Leukemia (ATL)

Patients with adult T‐cell leukemia/lymphoma (ATL) exhibit a variety of clinical features, and this disease is therefore clinically subclassified into acute, lymphomatous, chronic, and smoldering types. Acute ATL is a typical leukemic form of ATL with rapid progression, and chronic ATL is a less aggressive clinical form allowing long‐term survival even without chemotherapy. In the present study, we used fresh peripheral blood mononuclear cells (PBMC) from both types of ATL patients to identify molecules that may contribute to the difference between acute and chronic ATL. Isolated mRNAs expressed differentially between the two types of ATL include a T‐cell differentiation antigen (MAL), a lymphoid‐specific member of the G‐protein‐coupled receptor family (EBI‐1/CCR7), a novel human homologue to a subunit (MNLL) of the bovine ubiquinone oxidoreductase complex, and a human fibrinogen‐like protein (hpT49). We found that the former three are upregulated in acute ATL and the last is down‐regulated in both chronic and acute ATL. We speculate that dysregulation of the genes may account for the malignant features of ATL cells, in terms of growth, energy metabolism, and motility.