KRAS and cancer: Transgenic mouse models have established a causal relationship between K-Ras and p53 mutations in LC (Guerra et al, 2003; Tuveson et al, 2004; Meylan et al, 2009; de Seranno & Meuwissen, 2010; Farago et al, 2012), where cancer induction by urethane (Kelly-Spratt et al, 2009) or lung-specific expression of mutant p53273His either accompanied by K-Ras mutations or via conditional expression of oncogenic K-Ras showed that K-Ras mutations are an initiating event in NSCLC development (de Seranno & Meuwissen, 2010; Farago et al, 2012).