PAK1 and pancreatic neoplasm: Additionally, KRASG12D-driven pancreatic tumor formation was significantly impaired in Rac1-deficient mice [46], Pak1-deficient mice or those treated with anti-Pak1 [47], Rala/Ralb-deficient mice [48], Pik3ca variant–bearing mice [49,50], in mice deficient in both Mek1 and Mek2 or mice deficient in both Erk1 and Erk2 [51], and Raf1/Craf-deficient mice [48,51,52].