KLF2 and breast cancer: We propose that the loss of miR-126 oncosuppressive activity in BC mainly relies on the chromatin transcriptional silencing of EBF1, ETS2, and KLF2, leading to the upregulation (through reduced miR-126 expression) and downregulation (directly and/or indirectly, by reducing the expression of other TFs) of miR-126 target genes.