mTOR, a key downstream effector pathway of RAS35,36 involved in cell growth and protein synthesis,35,36 was strongly reduced in both KPC;KhkC−/− and KPC;KhkA/C−/− tumors, as shown by reduced expression of phospho-RPS6 in immunoblot analysis and by immunofluorescence staining of mouse tumor cells treated with mTOR inhibitor rapamycin, as well as from mouse tumor tissue sections (Figures 5D, 5E and S5C). This evidence concerns the gene RPS6 and neoplasm.