TP53 Y220C

This work establishes a mechanistic foundation for rational stabilizer design, proposing a new strategy centered on allosteric network restoration and mutation-adaptable anchoring. It offers broader implications for targeting conformationally unstable transcription factors previously considered "undruggable".

Our results demonstrated the viability of the DUBTAC strategy for p53 Y220C, successfully re-establishing conformation and promoting deubiquitination. More importantly, this study provides the first proof-of-concept for DUBTAC application in vivo, establishing targeted deubiquitination as a therapeutic approach.

Our findings position JC16 and JC36 as early-stage chemical leads with potential to restore mutant p53 function in a context-dependent manner. While their exact mechanism of action remains to be fully elucidated, these results provide a foundation for further development of indazole-based scaffolds as reactivators of the p53-Y220C mutant in cancer therapy.

In this work, we show that missense mutant forms of p53, which occur in >60% of HGSOC, bind and inhibit ERα function and confer resistance to fulvestrant and elacestrant. Mechanistically, we show that mutant p53 predominantly inhibits one arm of the ERα pathway-the transactivation of jointly regulated ERα-SP1 target genes such as the mTOR regulator DEPTOR We show that silencing mutant p53 restores the ability of ERα to transactivate ERα-SP1 target genes and renders HGSOC markedly more sensitive to endocrine therapy. Consistent with this premise, we show that the p53 mutant Y220C refolding compound rezatapopt enhances fulvestrant response in a Y220C mutant cell line.

The resulting bifunctional molecule promotes formation of a p53Y220C-PLK1 ternary complex, mislocalizes PLK1, inhibits PLK1 activity, elicits selective G2/M arrest and induces apoptosis in TP53Y220C cells while sparing wild-type TP53 cells. These data exemplify a potentially generalizable framework for targeting TP53 missense mutations by leveraging mutant p53 protein abundance to induce cell death, independent of p53's transcriptional activity.

P1/2, N=300, Recruiting, PMV Pharmaceuticals, Inc | N=230 --> 300 | Trial completion date: Jul 2026 --> Dec 2027 | Trial primary completion date: Mar 2026 --> Aug 2026

Overall, our study provides evidence that CGP significantly improves the identification of molecular targets in HGSOC, supporting its importance in the clinical practice to provide patients with more therapeutic options.

NCT04585750 (ClinicalTrials.gov).

P1, N=82, Not yet recruiting, Zhongshan Hospital, Fudan University; Zhongshan Hospital, Fudan University

Notably, co-treatment with Olaparib synergistically enhanced apoptosis, as indicated by increased caspase-3 and PARP1 cleavage and elevated γH2AX levels. These findings suggest that HO-3867 reactivates mutant p53 and potentiates Olaparib efficacy by promoting apoptosis and amplifying DNA damage, offering a promising therapeutic strategy for TP53-mutant ovarian cancer.

Our results demonstrated that these network theory-based protocols effectively detected the differential efficacies of small molecule allosteric effector drug compounds in restoring long-range electrostatic dynamics in the Y220C mutant. Furthermore, our approach identified key long-range electrostatic interactions critical to both the nominal and drug-rescued functionality of the p53-DBD, providing valuable insights into allosteric modulation and its therapeutic potential.

Rezatapopt is an investigational small molecule p53 reactivator that binds specifically to the Y220C-mutant p53 protein without interacting with wild-type or other mutant p53 proteins...There are several wild type Tp53 regulated pathways that could play a role in reversing the inflammatory response and tumor growth observed in this patient case. This perspective explores the signal transduction pathways involved in this cancer mediated inflammation and the extensive reduction of detectable tumor tissue.