TP53 and cancer: Researchers have designed a PROTAC that selectively targets MDM2 within p53-mutated/deficient TNBC cells, inducing proteasome-mediated degradation through high-affinity binding and VHL recruitment, thereby promoting TC apoptosis without toxicity to normal cells and significantly extending survival, offering an innovative potential therapeutic strategy for TNBC.327 In EGFR-mutated lung cancer brain metastasis models, upregulation of S100A9 in cancer cells activates the retinoic acid signaling pathway by upregulating ALDH1A1 expression, driving fatal brain recurrence.