PHGDH and leukemia: On the whole, the results of Cho et al. [22] establish that upregulation of PHGDH at the transcriptional level may be responsible for the elevated enzymatic activity reported in neoplasia by Snell et al. [18–20] and suggest that their assertion of application to human expression can be generalized to include most leukemias and lymphomas of human and murine origin.