BATF and breast cancer: In line with these observations, the identified candidate SEs for the essential genes listed above had prominent peaks for IRF4, vIRF3, and/or BATF in BC-3 cells (examples are shown in Fig. 3D and E; see also Fig. S7G and H), suggesting that the role of IRF4 in these SEs involves both vIRF3 and BATF.