MTHFD2 and cancer: However, in recent years, it was reported that C1 metabolism in the mitochondria was markedly enhanced in a comprehensive gene analysis of cancer cell lines and tumor tissues of cancer patients, such as serine hydroxymethyltransferase 2 (SHMT2) and methylenetetrahydrofolate dehydrogenase 2 (MTHFD2) [13, 14].