MAPK3 and lung carcinoma: We then focused on the MAPK and mTORC pathways, 2 major regulatory pathways of cell growth and survival (47, 48), and found that UBE2C knockdown caused moderate inactivation of MAPK signaling with a moderate reduction in p-ERK1/2, but significant inactivation of mTORC1/2 signaling with a remarkable reduction in p-S6K1/p-4EBP1 (mTORC1) and p-AKT (mTORC2) in both A427 and H1792 lung cancer cells (Figure 3A).