RAF1 and lung cancer: Transient knockdown (KD) of RASON using siRNA in human cells (H358, H23), KRASG12C mutant mouse lung cancer cells (LLC) and KRASG12C-transformed Ras-less mouse embryonic fibroblast cells (MEFG12C) resulted in significant downregulation of KRAS downstream signaling pathways, including the MAPK (RAF-MEK-ERK) and PI3K-AKT pathways (Fig. 2A).