Both JQ1 and PFI-1, another highly selective inhibitor of BRD4 and BRD2, also displayed significant antitumor activities in vivo in xenograft models of DLBCL, Burkitt’s lymphoma or acute myeloid leukemia and thereby improved survival of engrafted mice [399–402, 406]. This evidence concerns the gene BRD2 and Burkitt lymphoma.