E2F1 and breast cancer: Furthermore, regulators cross-linking these modules include the transcription factors STAT1, IRF1, E2F7, E2F1, E2F2, FOXM1, and MYBL2 which were significantly upregulated in BRCA1-MUT BC, and E2F1, FOXM1, STAT1, ZIC3, and IRF9 upregulated in BRCA2-MUT BC.