Pancreatic tumor trial identifies KRAS-p53 feedback loop as pan-cancer regulatory node

Investigators administered a dual KRAS G12D inhibitor and p53 reactivator to 42 patients with metastatic disease. Serial biopsies showed rapid collapse of MYC-driven transcription programs within 14 days, with 11 patients exhibiting partial responses lasting beyond six months. Single-cell RNA-seq confirmed loss of a 47-gene signature previously enriched in treatment-refractory clones.

The same KRAS-TP53 circuit appears in TCGA cohorts of lung, colorectal, and ovarian adenocarcinomas at frequencies above 65 percent. CRISPR perturbation screens in isogenic cell lines demonstrated that simultaneous disruption of both nodes reduces viability by 92 percent, exceeding single-target effects by 3.4-fold. No comparable synthetic lethality emerged from parallel screens against PI3K or CDK4/6.

Prior work focused on KRAS or p53 in isolation; the current data indicate the feedback loop itself constitutes the actionable target. Ongoing basket trials now stratify enrollment by circuit activity rather than histology. Regulatory filings for a companion diagnostic measuring the 47-gene signature are expected within 18 months.