MAPK1 and neoplasm: The addition of the cell-permeable WW peptide, which contains IQGAP1′s binding motif to the ERK protein, and therefore specifically blocks IQGAP1-mediated ERK activation, decreased tumor growth both in xenografts models and in a transgenic mouse model that spontaneously develops lethal pancreatic cancer, and extending the life span of the transgenic mice [22,125].