Mutant p53 drives ferroptosis resistance through metabolic plasticity in pancreatic cancer

Pancreatic cancer is one of the deadliest malignancies known to medicine, and its resistance to virtually every conventional therapy has long frustrated oncologists worldwide. Now, a team of researchers at the University of Verona in Italy has uncovered a mechanism that helps explain why pancreatic ductal adenocarcinoma, or PDAC, is so stubbornly difficult to kill—and, crucially, how that defense might be dismantled. In a study published in the journal Molecular Cancer, the group led by Massimo Donadelli and Alessandra Fiore demonstrates that mutant versions of the p53 protein, one of the most commonly altered genes in pancreatic cancer, actively protect tumor cells from ferroptosis, an iron-dependent form of cell death that has attracted intense interest as a therapeutic vulnerability. The findings suggest that combining ferroptosis-inducing drugs with agents that restore normal p53 function could open a powerful new front against this aggressive disease.

Ferroptosis is a relatively recent addition to the family of regulated cell death pathways, and it differs fundamentally from apoptosis, the form of cell death most traditional therapies aim to trigger. Instead of orderly cellular dismantling, ferroptosis is a violent, iron-driven process in which lipid membranes are destroyed by peroxidation—essentially, the cell’s fatty boundaries are oxidized until they rupture. Because cancer cells often possess elevated iron stores and heightened baseline oxidative stress, researchers have long hypothesized that they might be exquisitely sensitive to this form of death. Yet pancreatic tumors have proven resistant even to ferroptosis-inducing compounds, and the Verona team set out to discover why.

Their central suspect was p53, the famous “guardian of the genome.” In healthy cells, p53 acts as a tumor suppressor, halting cell division and initiating death programs when damage is detected. But in pancreatic cancer, the TP53 gene is frequently mutated—and, remarkably, many of these mutations do not merely disable the protein. Instead, they endow it with new, gain-of-function activities that actively promote tumor survival, metastasis, and therapy resistance. Whether mutant p53 influenced ferroptosis susceptibility had remained poorly understood, and the answer, it turns out, is emphatically yes.

To isolate the effect, the researchers employed isogenic pancreatic cancer cell models—cell lines that are genetically identical except for the status of TP53. Using CRISPR-Cas9 gene-editing technology, they created TP53 knockout cells in which the mutant gene was deleted entirely, and they also transiently overexpressed common mutant TP53 variants in these backgrounds. The comparison proved striking. When mutant TP53 was removed, pancreatic cancer cells became dramatically more vulnerable to ferroptosis. They accumulated more reactive oxygen species, suffered greater lipid peroxidation—as measured by markers including 4-hydroxynonenal—and displayed clear signs of mitochondrial dysfunction. The deletion of mutant p53, in other words, stripped away a protective shield, leaving the cells exposed to the oxidative assault that defines ferroptotic death.

Conversely, cells expressing mutant p53 preserved the structural integrity of their mitochondria under ferroptotic stress, sustaining their bioenergetic flexibility even as the lethal insult pressed in. Transmission electron microscopy and measurements of mitochondrial membrane potential confirmed that these cells kept their power factories functional where their p53-deficient counterparts faltered. This mitochondrial preservation was not a passive trait but the visible outcome of an elaborate adaptive program that mutant p53 orchestrates at the transcriptional level.

To map that program, the researchers turned to RNA sequencing, profiling the full complement of gene expression changes triggered by ferroptosis inducers in cells with and without mutant p53. The transcriptomic analysis revealed a multi-layered defensive network. Mutant p53-expressing cells ramped up antioxidant genes that neutralize the reactive oxygen species driving lipid peroxidation, and simultaneously activated a suite of metabolic genes. Among the most significant pathways to emerge was PI3K–AKT signaling, a pro-survival cascade that in these cells was linked to a selective shift toward glycolysis—the fermentation of glucose into lactate—as a means of maintaining cellular ATP, the universal energy currency.

That metabolic pivot proved to be the linchpin of the resistance. Using metabolic flux assays, the team measured both glycolytic activity and mitochondrial respiration, quantified through the oxygen consumption rate, and found that mutant p53-expressing cells could flexibly toggle between oxidative phosphorylation and glycolysis to keep their energy supply steady under stress. The functional consequences were demonstrated directly: supplementing the culture medium with extra glucose enhanced the survival of mutant TP53 cells treated with ferroptosis inducers, while blocking glycolysis with inhibitors such as 2-deoxy-D-glucose impaired their survival. Critically, neither manipulation had the same effect in TP53-knockout cells, confirming that the glycolytic lifeline exists only where mutant p53 is present.

The most clinically significant portion of the study came next. Rather than attacking the metabolic adaptation alone, the researchers tested whether pharmacological reactivation of wild-type p53 could collapse the entire defensive network. They used APR-246, also known as eprenetapopt, a small molecule designed to restore wild-type conformation and function to mutant p53, in combination with ferroptosis inducers including imidazole ketone erastin, a well-characterized inhibitor of the cystine transporter that fuels the antioxidant machinery of cells. The combination proved devastating to the tumor cells. Reactivating wild-type p53 disrupted the adaptive transcriptional and metabolic program, abrogated the glycolytic reprogramming that had sustained ATP production, and significantly increased ferroptotic cell death.

Importantly, this effect was not confined to laboratory dishes. The researchers validated their findings in orthotopic murine models—in which pancreatic tumors are established in the pancreas of living animals, recreating the tumor microenvironment far more faithfully than cell culture. In these models, the combination of p53 reactivation and ferroptosis induction significantly increased tumor cell death, providing in vivo evidence that the strategy could translate beyond the petri dish. The work also benefited from mouse KPC-derived cell lines, 7940Bb and MT3, derived from genetically engineered mouse models of pancreatic cancer and provided through collaborations with Cold Spring Harbor Laboratory and the University of Pennsylvania.

The implications for treatment are considerable. Pancreatic ductal adenocarcinoma is characterized by late diagnosis, rapid progression, and profound resistance to chemotherapy, radiotherapy, and the targeted agents that have transformed outcomes in other cancers. Most patients survive only months after diagnosis, and the five-year survival rate remains among the lowest of any major cancer. Ferroptosis induction has been proposed as a way around this resistance precisely because it targets vulnerabilities—iron metabolism, lipid repair, antioxidant defense—that conventional therapies ignore. But the Verona study demonstrates that pancreatic tumors are not passive targets: mutant p53 endows them with a metabolically flexible, transcriptionally orchestrated armor that must be breached for ferroptosis to succeed.

The study also adds a new dimension to the biology of mutant p53 gain-of-function. Rather than simply evading apoptosis or promoting proliferation, mutant p53 here acts as a metabolic arbiter, rewiring how cells produce and protect energy so that lethal lipid peroxidation can be withstood. It links three of the hottest themes in modern cancer research—p53 biology, ferroptosis, and metabolic plasticity—into a single mechanistic framework. The finding that PI3K–AKT signaling couples p53 mutation to glycolytic shift suggests additional pharmacological points of intervention; the researchers demonstrated that glycolytic inhibition and PI3K pathway blockade each undermined the survival advantage of mutant TP53 cells under ferroptotic stress.

The authors are careful to frame the work as preclinical, and substantial hurdles remain before a combination of eprenetapopt and ferroptosis inducers reaches the clinic. Eprenetapopt itself has had a mixed record in clinical trials for blood cancers, and questions of drug delivery to the dense, poorly vascularized pancreatic tumor microenvironment remain formidable. Still, the identification of a therapeutically actionable vulnerability—one that can be pharmacologically flipped—offers a rare piece of good news in a disease that has seen painfully few. The work was supported by the Italian Association for Cancer Research, the Italian Ministry of University and Research, and European recovery fund programs, reflecting sustained investment in pancreatic cancer metabolism research at Verona.

What makes the study resonate beyond pancreatic cancer is the broader principle it establishes: cell death pathways do not operate in isolation from tumor metabolism, and the mutated genes that drive cancer also decide which death programs remain available. For the many tumors that harbor TP53 mutations, the ability of restored wild-type p53 to sensitize cells to ferroptosis suggests a generalizable combination strategy. For patients with pancreatic ductal adenocarcinoma—a disease desperate for options—the demonstration that a drug pair can strip away a tumor’s metabolic armor and ignite ferroptosis from within represents exactly the kind of mechanistic insight from which the next generation of therapies may be built.