However, expression of viral virulence factors such as Tax and HTLV-1 bZIP factor (HBZ), and host epigenetic and immune changes, in particular expression of cytokines, activate NK cells and T-lymphocytes; the altered cell signalling pathways subsequently promote progress toward HAM/TSP and ATLL [3–5]. Here, CNTN2 is linked to adult T-cell leukemia/lymphoma.