PRDM9 and adult T-cell leukemia/lymphoma: Although recent treatment modalities for ATLL such as the immunomodulator lenalidomide, anti-CCR4 antibody mogamulizumab, histone deacetylase inhibitor tucidinostat, and histone methyltransferase EZH1/2 dual inhibitor valemetostat are available in Japan for the treatment of ATLL, these treatment options lack antiviral approaches to suppress HTLV-1 replication and transmission70–73.