The effect of 5-Lox inhibition on the K-Ras pathway was examined and found that 5-Lox inhibition by MK591 or shRNA dramatically inhibits the protein level of K-Ras and downstream activating phosphorylation of c-Raf and ERKs in pancreatic cancer cells (Figures 5I, J). This evidence concerns the gene KRAS and pancreatic neoplasm.