In addition, another major problem with BRD4 inhibitors is that drug resistance to BRD4 inhibitors often appears in various cancer types with different mechanisms of action, especially as BRD4 inhibitors are less effective in solid tumors than in hematological malignancies (Jin et al., 2018; Pawar et al., 2018; Wang W. et al., 2021). This evidence concerns the gene BRD4 and cancer.