The genes, MMP9, OPN (SPP1), TIMP1, TIMP2, TGFβ1, p14ARF, AKT1, HRAS, BRAF, and RKIP, presented equal expression levels between BC and normal tissue; whereas genes that presented significantly lower expression levels in BC vs. normal tissue were MMP2, FGF2, ARAF and RAF1. This evidence concerns the gene MMP9 and breast cancer.