KRAS and pancreatic neoplasm: A recent study better clarified the role of LKB1 in promoting pancreatic cancer development showing that the oncogenic cooperation between LKB1 loss and KRAS activation is mediated by pronounced mTOR activation, which in turn activates the serine-glycine-one-carbon pathway coupled to S-adenosylmethionine generation; in parallel, DNA methyltransferases are upregulated, leading to elevation in DNA methylation, particularly at the level of retrotransposon elements, with their consequent silencing [246].