For decades, cancer medicine has largely worked by blocking the parts of a tumor that keep it alive, like a lock jammed against a door. A team at the University of Michigan has tried something less intuitive: a molecule that binds two prostate cancer-driving proteins, the androgen receptor and its helper p300, and holds them together in a configuration that disables them. In laboratory and animal studies, this approach has shown far greater tumor-killing power than the conventional pairing of separate inhibitors, while leaving healthy cells largely untouched. Whether this quiet rewiring of cel
Molecular 'Glue' Reprograms Prostate Cancer Proteins in Preclinical Study
Instead of blocking the proteins, they glued them together
Mark
What's actually new here? Drugs that target AR and p300 already exist as inhibitors.
Mimi
The new part is the strategy. Instead of blocking each protein, the molecule joins them in an abnormal configuration that traps both in an inactive state, shutting down two pathways at once.
Mark
And the results were better than using both inhibitors together?
Mimi
Yes. The team reports greater tumor killing than the combined inhibitors, and less effect on normal cells. Wang puts the potency at about 1,000 times higher in tumor cells.
Luke
That 1,000-fold figure comes from the lead researcher describing the optimized molecule in laboratory tumor cells. It isn't a patient outcome, and the source doesn't say how it was measured.
Mark
What about the resistant tumors?
Mimi
In animal models, the approach produced durable responses and worked against tumors resistant to standard treatments. Chinnaiyan framed it as an opportunity for castration-resistant disease, if it translates.
Luke
That 'if' carries a lot. Cell lines, mice and organoids are the evidence so far. We don't know yet about safety in humans, or what dose would work.
Mark
Why does the oral detail matter?
Mimi
Making the molecules orally bioavailable is a step toward a pill, which would be far more practical for patients.
Luke
Still a step, not an arrival. The team says it is looking for a drug candidate suitable for human trials, so none has been chosen yet. The claim that it could work in other cancers is also a belief, not a result.
Il Polso
- Prostate cancer that has stopped responding to standard treatment leaves patients with few options, and this study aims to change that.
- Researchers are gluing the androgen receptor and p300 together, trapping them in an inactive state instead of simply blocking them.
- The lead molecule proved about 1,000 times more potent against tumor cells than combined inhibitors, while sparing normal cells.
- Mice with resistant tumors responded durably, and the molecules were optimized for oral dosing, a step toward pill form.
- The work is still preclinical, and the team is now hunting for a drug candidate ready for human trials.
For decades, cancer medicine has largely worked by blocking the parts of a tumor that keep it alive, like a lock jammed against a door. A team at the University of Michigan has tried something less intuitive: a molecule that binds two prostate cancer-driving proteins, the androgen receptor and its helper p300, and holds them together in a configuration that disables them. In laboratory and animal studies, this approach has shown far greater tumor-killing power than the conventional pairing of separate inhibitors, while leaving healthy cells largely untouched. Whether this quiet rewiring of cellular partnerships can cross from mice and cell cultures into human patients remains an open question.
Most cancer drugs work by blocking something inside a tumor. Researchers at the University of Michigan Health Rogel Cancer Center tried the reverse. They designed a molecule that locks two cancer-driving proteins into a new, disabled arrangement, and in preclinical work it outperformed the usual approach.
The two proteins are the androgen receptor, known as AR, and a helper called p300. Together they switch on genes that fuel prostate cancer growth. Instead of breaking their partnership apart, the team joined them in an abnormal configuration using a bifunctional molecule they called DALTAC. Arul Chinnaiyan, who co-led the study, described it as a brace that traps both proteins and shuts down two growth pathways at once. The chemistry came from Shaomeng Wang's lab, which built each molecule from two linked inhibitors.
Testing spanned prostate cancer cell lines, mice, and three-dimensional organoids grown from human cells. The molecules killed tumor cells far more effectively than the two inhibitors used separately, and the optimized version was roughly 1,000 times more potent against tumor cells while sparing normal ones. In mice, responses were durable, including in tumors that had resisted standard treatment. The molecules were also refined for oral absorption, a key step toward a pill.
The researchers see this as part of a growing field called chemically induced proximity, which also includes PROTACs. They believe reprogramming protein interactions could eventually reach other cancers and other proteins. For now, the teams are searching for a candidate ready for human trials, and the outcome of that search remains unknown.
Most cancer drugs work by blocking something: a protein, a signaling pathway, a single step in the machinery a tumor uses to grow. Researchers at the University of Michigan Health Rogel Cancer Center have tried the opposite for prostate cancer. They designed a molecule that binds two cancer-driving proteins together and holds them there, and in preclinical work it outperformed the conventional approach.
The two proteins are the androgen receptor, known as AR, and a helper protein called p300. Together they activate genes that fuel prostate cancer growth. Rather than trying to break up that partnership, the team used a bifunctional small molecule to join the proteins in an abnormal configuration. The researchers named the approach DALTAC, short for domain-alteration chimeras. The findings are published in Nature.
Arul M. Chinnaiyan, M.D., Ph.D., a senior author of the study, director of the Michigan Center for Translational Pathology and the S.P. Hicks Professor of Pathology at Michigan Medicine, described the molecule as a kind of brace. It connects the two proteins and traps them in an inactive state, he said, shutting down two oncogenic signaling pathways at once.
The chemistry comes from the lab of Shaomeng Wang, Ph.D., the other senior author. Wang is the Warner-Lambert/Parke-Davis Professor in Medicine and directs the Michigan Center for Therapeutic Innovation. He explained that each molecule consists of two inhibitors joined by a carefully designed short linker. By gluing the proteins together, the molecules change how the proteins naturally interact. The work paired the Chinnaiyan laboratory's expertise in prostate cancer biology with the Wang laboratory's strength in medicinal chemistry and drug discovery.
The team tested the approach in prostate cancer cell lines, in mouse models, and in three-dimensional organoids derived from human cells. The DALTAC molecules were substantially more potent and more effective at killing tumor cells than a combination of AR and p300 inhibitors used separately, and they showed strong selectivity for tumor cells over normal cells. Wang said the optimized molecule was approximately 1,000 times more potent in tumor cells than the combined inhibitors, while sparing normal cells that lack these protein interactions. In animal models, the approach produced durable responses and worked against tumors that had become resistant to standard treatments.
The researchers also optimized the molecules for oral bioavailability, which Wang called a key step toward a pill for patients. Chinnaiyan called the preclinical results remarkable and said the durable responses point to an opportunity for a more effective treatment for advanced prostate cancer, including castration-resistant prostate cancer, if the findings translate to patients.
The work belongs to a growing field called chemically induced proximity, in which small molecules bring proteins together to change cellular functions. Other approaches in the field include proteolysis-targeting chimeras, or PROTACs, which trigger the degradation of specific proteins, and transcriptional/epigenetic chemically induced proximity, or TCIP.
The research remains at the preclinical stage. Wang said the teams are working closely to identify a drug candidate suitable for human clinical trials. The researchers also believe that reprogramming protein interactions could be a broadly applicable drug development strategy, with possible uses in cancers beyond prostate cancer and for proteins beyond AR and p300. The co-first authors are Jie Luo of the Chinnaiyan lab and Jianzhang Yang of the Wang lab, joined by a long list of additional collaborators.
Citazioni salienti
Our molecule acts like a molecular brace, connecting these two cancer-driving proteins in an abnormal configuration that traps them in an inactive state.— Arul M. Chinnaiyan, M.D., Ph.D., senior study author
Our teams are working closely to identify a drug candidate suitable for testing in human clinical trials.— Shaomeng Wang, Ph.D., senior study author
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