PHGDH and neoplasm: Of note, the dominant-positive role of 3-PGA binding-defective PHGDH-T57A in phosphorylation of p53-Ser58 was observed across the entire liver of mice without starvation (Supplementary information, Fig. S4c); inside the DEN-induced HCC liver, the increase of the p-Ser58 signal was most evident in the peripheral areas of HCC tumors but not in the most nutrient-stripped central areas of the tumor, where the levels of p-Ser58 were already constitutively high (Fig. 5a, b; see also refs. 64,65).