In the current study, depletion of NCOA3-p300-NF-κB members and NCOA3 inhibitors simultaneously decreased the expression levels of BCL2, BCL2A1, BCL2L2, and MCL1, suggesting that targeting NCOA3 or the assembly of the NCOA3-p300-NF-κB complex might be a new and effective approach for inhibiting breast tumor growth. Here, EP300 is linked to breast neoplasm.