KRAS and familial pancreatic carcinoma: Specifically, in tumors bearing wild-type Raf but mutant Ras (such as pancreatic cancer), Raf inhibitors create feedback activation of MAPK signaling by inducing dimerization of cRaf with BRaf and interaction with the oncoprotein Kras-GTP (Hatzivassiliou et al., 2010; Heidorn et al., 2010; Poulikakos et al., 2011).