While miR-34a is downregulated in many cancer types [152,153,154], we observed that miR-34a is more abundant in HTLV-1-infected cell lines and in ATLL cells compared to control CD4+ cells [136,155], and provided evidence that both p53 and NF-κB promote miR-34a expression in the context of HTLV-1 infection [136]. The gene discussed is CD4; the disease is adult T-cell leukemia/lymphoma.