IRF4 and cancer: Importantly, in normal and cancer cells, more than half of all BRD4 proteins are bound to a small number of enhancers (super-enhancers) that control the expression of genes fundamental to the control and establishment of individual cell identities, such as PAX5, BCL6, CD79A, CD79B, FOXO1 in B-cells or PRDM1, IRF4 and MUM1 in plasma cells [22–24].