Immune Senescence-Related Gene Expression Profile in CD4+ T-Lymphocytes of HTLV-1 Asymptomatic Carriers and Patients with Adult T-Cell Leukemia/Lymphoma (ATLL): A Brazilian Preliminary Study

Introduction: Adult T-cell leukemia/lymphoma (ATLL) is a rare and aggressive neoplasm caused by the human T-lymphotropic virus type 1 (HTLV-1). It is estimated, worldwide, that at least 5-10 million people carry HTLV-1 and 2-5% out of them will develop ATLL. Previously, our group demonstrated an increase of cells in G0/G1 phase of cell cycle and aneuploidy in CD4+ T-cells in HTLV-1 asymptomatic carriers [1]. These findings may reflect an adverse intracellular environment, caused by genetic stress due to viral particles inserted into host DNA. Intracellular mechanisms aiming to control and prevent replication of cells carrying genetic aberrations in genes involved in cell cycle regulation, DNA repair and apoptosis could be activated to hold cell division while DNA damage is repaired. Based on this hypothesis, delay of cell cycle in G0/G1 may be a step in the process of oncogenesis [1]. Herein, we did a pilot study in order to analyze the pattern of expression of a set of genes involved in cell cycle control and senescence in CD4+ T-lymphocytes of HTLV-1 infected individuals searching for additional genetic abnormalities in this setting.