Rac1b can mediate EMT and genomic instability induced by MMP3 by producing ROS in certain microenvironments, thus increasing the malignant transformation of breast cancer cells [75].Under pathological conditions, Rac1 activation can mediate EMT in cells [76] and induce invasion and metastasis of a breast cancer cell line model in vivo by promoting cell migration [77]. This evidence concerns the gene MMP3 and breast cancer.