E2F1 and breast cancer: Concerned with the score of the possible TFs predicted by JASPAR, we overexpressed CREB, SP1, EGR1, KLF5, ELK1, TFAP2A, GCF4, C/EBP alpha, SP3, and E2F1 by transfecting overexpression vector, pcDNA3.1 and P-Enter as empty vectors in BC cells.