PHGDH and cancer: Recent findings suggest, for example, that EHMT2 depletes serine and its downstream metabolites by repressing the transcription of genes involved in their biosynthesis such as phosphoglycerate dehydrogenase (PHGDH), phosphoserine aminotransferase 1 (PSAT1), phosphoserine phosphatase (PSPH), and serine hydroxymethyltransferase 2 (SHMT2) leading to a growth arrest in cancer cell lines of different tissue origins [22].