Lee et al. (2015) found the following phenomenon in the study of the treatment mechanism of JQ1—a bromodomain and extra terminal domain (BET) protein inhibitor—in human osteosarcoma: although the inhibition of bromodomain-containing protein 4 (BRD4) by JQ1 could inhibit the growth of osteosarcoma cells in vitro. The gene discussed is BRD4; the disease is osteosarcoma.