TP53 and neoplasm: In this study, we comprehensively investigated genomic and transcriptomic differences between Rs and NRs to 5-FU and oxaliplatin-based chemotherapy, estimated from PDX experiments, and identified several important tumor biology pathways associated with drug response (Fig. 6a, b): (1) defective p53 signaling, in NRs; (2) increased metabolic processes, in Rs; and (3) increased cell-to-cell and cell-to-ECM interactions, in NRs.