PHGDH and neoplasm: Cho et al. [22] then sought to determine what happens to the differential expression of PHGDH-specific mRNA in malignant human tumor cells and whether the anticipated elevation in PHGDH protein expression is due to upregulation of PHGDH mRNA at the transcriptional level or is instead the result of modifications in enzymatic characteristics such as Km, Vmax⁡, and/or stability.