While MYC is the key target of JQ1 in hematopoietic cancers, FOSL1 is a major JQ1 target in lung adenocarcinoma [134] and other solid tumors, such as osteosarcoma and childhood sarcoma, in which Fra-1 downregulation phenocopies the effect of the BRD4 inhibitor [135,136]. Here, FOSL1 is linked to hematopoietic and lymphoid cell neoplasm.