MAPK7 and neoplasm: ERK5 is also implicated as having a role in tumor cell invasion,with its activity in triple-negative breast cancer cell lines maintainingthe expression of the transcription factor Slug, which represses genesinvolved in an epithelial-to-mesenchymal transition.34 Furthermore, ERK5 has been shown to induce the phosphorylationof FAK to promote cell motility but in an ERK5 kinase-independentmanner.31 Consistent with these findings,ERK5 silencing has been shown to reduce the invasion of breast tumorcell lines in vitro and the metastasis of breast cancer xenograftsin vivo.34,31,35