MiR-193a-3p downregulation was observed in HER2+ BC cells and tissues, and Tang et al. [46] demonstrated that miR-193a-3p methylation led to the progression of HER2+BC by targeting GRB7, that was frequently co-expressed with HER2 and correlated with a metastatic phonotype, ERK1/2, the phosphorylation of which was increased by GRB7 and FOXM1, a transcriptional regulator overexpressed in HER2+ cancers and activated by cyclin–cyclin dependent kinase and ERK-induced phosphorylation. Here, MAPK3 is linked to breast cancer.