In turn, the FOXP3+ T cells exert both potentially beneficial and harmful effects: they may suppress the growth of autologous ATLL clones and also may suppress the host's cytotoxic T lymphocyte response, which normally limits HTLV-1 replication and reduces the risk of HTLV-1 infection-associated diseases. Here, FOXP3 is linked to adult T-cell leukemia/lymphoma.