To test our hypothesis that exposure to platinum may induce a metabolic rewiring involving, among other processes, also downregulation of serine biosynthesis, we measured PHGDH levels in the OVC1a PDX model, established from a chemo-naïve platinum sensitive tumor, and in the matched OVC1b PDX model, established from the clinical relapse after platinum treatment in the same patient (Supplementary Table 3). This evidence concerns the gene PHGDH and neoplasm.