Scientists Used a Hydrogel to Reprogram Cancer Cells in Just 24 Hours. Here's Why It Matters

Researchers at Hokkaido University in Japan, working with collaborators at Japan's National Cancer Center Research Institute, demonstrated a technique that does something remarkably close to that.

In a study published in Nature Biomedical Engineering in 2021, the researchers reported that a specially designed hydrogel could rapidly reprogram differentiated cancer cells, encouraging them to acquire characteristics associated with cancer stem cells. The changes appeared within approximately 24 hours in experiments involving six human cancer cell lines.

The finding matters because cancer stem cells are associated with tumor growth, treatment resistance, and the recurrence of some cancers. Studying these cells can be difficult because they may represent only a small proportion of the cells in a tumor.

The researchers' approach offers a way to generate cancer stem-cell-like populations in the laboratory, potentially making it easier to investigate their biology and identify vulnerabilities.

The surprising part is the material itself.

The hydrogel is a water-rich polymer network designed to provide cells with a particular physical environment. Rather than relying exclusively on added biological signals or genetic manipulation, the researchers used the properties of the material beneath the cells to influence their behavior.

The discovery illustrates a growing principle in biomedical science: the physical environment surrounding a cell can influence what that cell becomes and how it behaves.

It does not mean that a hydrogel cures cancer or that every cancer cell can be transformed in the same way. The results are experimental findings that offer researchers a new tool for investigating a difficult problem in cancer biology.

A hydrogel is a material made from a network of molecules that can absorb and retain large amounts of water.

Its structure combines the wet, soft characteristics of a water-rich environment with a network that gives the material its physical form.

Hydrogels can be manufactured with different chemical compositions, stiffnesses, charges, and internal structures. Those differences can influence how cells attach to a surface, interact with their surroundings, and respond to physical and chemical signals.

Because living tissues also contain large amounts of water and have complex physical structures, hydrogels are widely studied in biomedical engineering.

Researchers investigate them for applications including tissue engineering, wound dressings, drug delivery, cell culture, and regenerative medicine.

But hydrogels are not all alike. A material designed to support one type of cell may have a very different effect on another.

That variation was central to the Hokkaido University research.

What makes the researchers' hydrogel different?

The team used a material called a double-network hydrogel, or DN gel.

A double-network gel contains two interpenetrating polymer networks. Combining the networks can produce distinctive mechanical and chemical properties that differ from those of either network used alone.

The researchers investigated whether this specially engineered material could reproduce aspects of the cellular environment associated with cancer stem-cell behavior.

They discovered that cancer cells placed on the gel rapidly formed three-dimensional spherical clusters and displayed changes in gene expression associated with stem-cell characteristics.

The response was not reproduced in the same way by the comparison materials used in the study.

This suggested that the gel's particular combination of properties mattered. It was not simply a case of placing cancer cells on any wet surface.

Cancer stem cells, often abbreviated CSCs, are a population of cancer cells that exhibit stem-cell-like properties.

Depending on the tumor and experimental context, these properties can include self-renewal, the ability to generate different tumor-cell populations, and an ability to contribute to tumor growth.

The term does not mean that these cells are ordinary healthy stem cells that have simply moved into a tumor. They are cancer cells with particular biological characteristics.

Researchers study them because some cancer stem-cell populations appear to survive treatments that eliminate more sensitive tumor cells.

If surviving cells retain the capacity to regenerate a tumor, they may contribute to cancer returning after an initial response to treatment.

However, cancer stem-cell biology is complex. The importance of these cells varies across cancer types, and the markers used to identify them are not universal. Researchers cannot assume that one marker or laboratory test identifies every clinically relevant cancer stem cell.

Why can they be difficult to study?

In many tumors, cells with stem-like characteristics may be relatively uncommon.

Researchers trying to understand these cells face several challenges:

• They may be mixed with much larger populations of other cancer cells.
• Their characteristics can change depending on their environment.
• There is no single universal marker that reliably identifies every cancer stem cell in every tumor.
• Isolating enough representative cells for experiments can be difficult.
• Laboratory conditions may alter the very properties researchers want to investigate.

These obstacles make it harder to study the molecular mechanisms associated with treatment resistance and recurrence.

A reliable method for generating cancer stem-cell-like populations could help researchers obtain more material for experiments and investigate how these cells differ from other tumor cells.

That is the problem the hydrogel approach was designed to address.

The researchers investigated whether the physical and chemical properties of the cell-culture environment could encourage cancer cells to acquire stem-like characteristics.

They placed differentiated cancer cells on the double-network hydrogel and observed their behavior over time.

Within approximately 24 hours, the cells formed spherical structures and displayed changes associated with cancer stem-cell characteristics.

The team detected increased expression of several genes associated with stemness, including SOX2, OCT3/4, and NANOG.

These genes are involved in biological programs associated with stem-cell identity and cell-state regulation. Their expression can provide important evidence that a cell's biological state is changing.

But gene markers alone do not prove that a cell has every functional property of a cancer stem cell. Researchers need additional experiments to determine what the cells can do.

The team therefore investigated the biological behavior of the cells, not just their appearance.

What does "reprogramming" mean here?

In biology, reprogramming refers to a change in a cell's state or identity.

A cell's behavior is influenced by its genetic information, gene regulation, signaling pathways, and surrounding environment. Changes in those factors can alter which genes are active and which biological programs the cell follows.

The hydrogel did not need to rewrite the entire DNA sequence of each cancer cell to produce a change in cell state.

Instead, the research indicated that the material could trigger changes in cellular signaling and gene expression associated with stem-like behavior.

This distinction is important. Reprogramming a cell's characteristics does not necessarily mean changing its underlying DNA sequence.

The researchers' findings support the idea that the cell's physical environment can help regulate its biological identity.

One of the notable aspects of the original study was that the researchers did not investigate only a single type of cancer cell.

They reported rapid induction of cancer stem-cell characteristics in six human cancer cell lines representing:

• Brain cancer
• Uterine cancer
• Lung cancer
• Colon cancer
• Bladder cancer
• Sarcoma

The study also included brain cancer cells obtained from a patient with glioblastoma.

This breadth matters because different cancers can have very different genetic alterations, signaling pathways, and responses to their environment.

A technique that works in one cell line may not work in another.

The results suggested that the hydrogel approach could have broader research applications than a method restricted to a single tumor model.

However, the six cell lines do not represent every cancer type, every patient, or every biological subtype of those cancers.

The findings should therefore be understood as evidence of a promising laboratory technique — not proof of a universal process that can turn any cancer cell into a cancer stem cell.

Cancer cells can form clusters for several reasons. A spherical shape alone does not establish that a group of cells has acquired cancer stem-cell properties.

To investigate the significance of the observed changes, the research team examined molecular markers and tested the biological behavior of the resulting cells.

The team reported elevated expression of stemness-associated genes, including SOX2, OCT3/4, and NANOG.

They also tested brain cancer cells grown on the double-network hydrogel in an animal model.

When the hydrogel-cultured cells were injected into the brains of immunodeficient mice, they showed greater tumor-forming ability than cells cultured on single-network gels under the study's comparison conditions.

This result provided additional evidence that the changes were biologically meaningful.

Nevertheless, animal experiments are not equivalent to clinical trials. The findings do not demonstrate that the method improves patient outcomes, predicts how a human tumor will respond to treatment, or provides a new therapy.

The experiment's significance is that it gave researchers a way to generate and investigate cancer cells with characteristics associated with stemness under controlled conditions.

That can help scientists ask questions that are otherwise difficult to answer.

At first glance, deliberately encouraging cancer cells to develop properties associated with treatment resistance may sound counterproductive.

The researchers' objective, however, was not to make cancer more dangerous in patients. It was to create a more accessible laboratory model for studying cancer stem cells.

The logic is straightforward: if researchers can reliably generate cells with relevant characteristics, they may be able to study those cells in greater detail and test possible ways of targeting them.

Investigating treatment resistance

Some cancer stem-cell populations can be relatively resistant to chemotherapy or radiation in particular experimental and clinical settings.

Researchers want to understand what makes these cells survive, whether the relevant mechanisms differ between tumors, and which pathways might be vulnerable to treatment.

A laboratory model that generates stem-like cancer cells could help researchers compare their responses with those of other tumor cells.

For example, investigators might examine differences in gene expression, cell signaling, metabolism, or sensitivity to candidate drugs.

Such experiments could help identify promising targets for further investigation.

Understanding cancer recurrence

Cancer can return even after a treatment has reduced a tumor substantially.

There are multiple reasons this can happen, including residual disease, tumor evolution, and the survival of cells that escape treatment.

Cancer stem cells are one important area of research into this problem, although they are not the sole explanation for recurrence in every cancer.

By studying cells with stem-like properties, researchers can investigate how these populations survive, reproduce, and interact with their environment.

A hydrogel that helps generate such cells could make those investigations easier.

Identifying potential drug targets

Researchers may use hydrogel-generated cells to investigate molecular pathways that distinguish them from other cancer cells.

If a pathway proves important for maintaining a harmful cellular state, scientists can test whether disrupting it changes the cells' behavior.

This process can generate hypotheses for new therapies, but identifying a possible target is only an early step. The target must be validated, and any potential treatment must undergo extensive testing for effectiveness and safety.

The hydrogel is a research tool that could support this process. It is not itself an established cancer treatment.

One of the most interesting questions is how a material's physical properties can influence cellular behavior.

Cells do not exist in isolation. In living tissue, they interact with surrounding molecules, neighboring cells, and the extracellular matrix — the network of proteins and other materials that helps support tissue structure.

These interactions can influence signaling pathways that regulate growth, movement, differentiation, and survival.

A laboratory surface can change those interactions.

Its stiffness, charge, molecular composition, and ability to interact with proteins can all affect how a cell senses and responds to its environment.

This area of biology is closely connected to mechanobiology, the study of how physical forces and mechanical properties influence living systems.

The role of physical and chemical signals

The Hokkaido University research suggested that the double-network hydrogel's properties created conditions that encouraged cancer cells to acquire stem-like characteristics.

The researchers investigated molecular mechanisms involved in this response, including calcium-channel signaling and the protein osteopontin.

Calcium signaling is used by cells to regulate a wide range of processes. Osteopontin is a signaling-related protein involved in several biological contexts, including interactions between cells and their surroundings.

The study identified these mechanisms as important parts of the reprogramming process.

The result illustrates how a physical material can influence biological signaling rather than acting only as a passive support.

Scientists are still investigating how the material's different properties interact with the molecular machinery inside cells. Understanding those relationships could help researchers design more precise laboratory environments for studying cancer.

The double-network hydrogel study was published in 2021, but the broader idea of using engineered materials to induce cancer stem-cell characteristics has continued to attract research interest.

In a 2024 review-style article published in the Japanese Journal of Pediatric Hematology/Oncology, Hokkaido University researcher Shinya Tanaka discussed the creation of cancer stem cells using hydrogels and the concept known as hydrogel-activated reprogramming, or HARP.

The article describes the observation that cells placed on certain hydrogels can form spherical structures within 24 hours while increasing the expression of stemness-associated markers.

The work reflects an ongoing effort to understand how the physical environment can influence cancer-cell states and how the phenomenon might be used in cancer research.

A 2025 study examined pancreatic cancer cells

A further study published in Biochemical and Biophysical Research Communications in 2025 investigated a different hydrogel, called PCDME, in pancreatic cancer cells.

The researchers reported that the hydrogel rapidly induced pancreatic cancer cell spheroids with elevated levels of stemness-associated markers, including SOX2, OCT3/4, and NANOG.

The study also reported a change in the cells' growth behavior and examined associated metabolic characteristics.

This work is relevant because pancreatic cancer is an area in which researchers are actively investigating treatment resistance and the biology of cancer stem-cell populations.

However, the 2025 paper should not be confused with the original double-network hydrogel experiment. It examined a different material and a particular pancreatic cancer model.

Nor does it establish that every hydrogel will produce the same result or that the method is ready for clinical use.

Taken together, these studies suggest that researchers are exploring engineered hydrogels as a way to manipulate and study cancer-cell states in controlled laboratory environments.

One possible long-term application is the study of cancer cells obtained from individual patients.

Cancer varies substantially between people. Even tumors that originate in the same organ can have different genetic changes, signaling pathways, and responses to treatment.

A treatment that works well for one tumor may be less effective against another.

Researchers are therefore investigating ways to use patient-derived cells and laboratory models to learn more about individual cancers.

If a hydrogel-based method can reliably generate relevant cancer stem-cell-like populations from patient samples, it might help investigators study the biology of those cells and test candidate treatments in the laboratory.

This could eventually contribute to research into personalized medicine.

However, several steps would be needed before such a method could become a validated clinical tool.

Researchers would have to determine how reliably it works across different patient samples, whether the resulting cells accurately represent important features of the original tumor, and whether laboratory drug responses predict responses in patients.

They would also need standardized procedures, quality controls, and evidence that the results are useful for clinical decision-making.

The current findings establish a research opportunity, not a clinically validated personalized-treatment system.

The hydrogel research is promising, but understanding its limitations is essential.

Laboratory cells are not the same as a whole tumor

Cancer cells grown in a laboratory do not reproduce every feature of a tumor inside the human body.

Real tumors contain blood vessels, immune cells, connective tissue, signaling molecules, and many interacting cell populations. Their environments also change over time.

A hydrogel can recreate selected physical or chemical features, but it cannot automatically reproduce the entire complexity of a tumor.

Cancer stem-cell characteristics are not defined by one marker

The expression of genes such as SOX2, OCT3/4, and NANOG provides evidence of changes associated with stemness, but no single marker is sufficient to establish every functional property of a cancer stem cell.

Different cancers can display different combinations of markers and behaviors.

Researchers therefore need to consider multiple lines of evidence when characterizing the cells generated by a hydrogel.

Results may depend on the cancer type and material

The original study showed responses across six cancer cell lines and patient-derived glioblastoma cells, but that does not guarantee identical behavior in every tumor.

The material's composition and physical properties matter. So do the biological characteristics of the cells being studied.

Further research is needed to establish which combinations are most effective and why.

A research method is not a treatment

The study did not demonstrate that the hydrogel kills cancer, prevents recurrence in patients, or improves survival.

Its potential value is indirect: it could help scientists study cancer stem cells and investigate treatments aimed at them.

Any candidate treatment developed using this model would still require rigorous testing.

These limitations do not diminish the importance of the research. They define what scientists need to investigate next.

The hydrogel study highlights a broader idea in modern science: materials can do more than provide a structure for living cells.

Under the right conditions, the material surrounding a cell can influence its signaling pathways and behavior.

This insight is relevant to tissue engineering, regenerative medicine, developmental biology, and cancer research.

Researchers are increasingly designing laboratory environments to control selected aspects of how cells experience their surroundings. By adjusting physical and chemical properties, they can investigate how those conditions influence cell identity and function.

The goal is not to assume that a material can control every aspect of biology. Rather, it is to understand which features of the environment matter, how they influence cells, and how those effects can be used to answer scientific questions.

In cancer research, the ability to generate hard-to-study cellular states could make it easier to investigate the mechanisms behind treatment resistance and recurrence.

The double-network hydrogel is one example of how materials science and cell biology can work together to address that challenge.

The hydrogel research from Hokkaido University demonstrates that the environment surrounding a cancer cell can influence its biological state.

By using a specially engineered double-network hydrogel, researchers induced cancer stem-cell-associated characteristics in laboratory-grown cells within approximately 24 hours. The team reported effects across six human cancer cell lines and investigated the behavior of cells derived from a glioblastoma patient.

The discovery offers a practical research opportunity. Cancer stem-cell populations can be difficult to isolate and study, and a technique that generates them in the laboratory may help researchers investigate their biology and search for vulnerabilities.

Follow-up work, including a 2025 study involving pancreatic cancer cells, suggests that engineered hydrogels remain an active area of investigation.

But the distinction between research and treatment matters. The hydrogel is not a demonstrated cancer cure, and the findings do not establish that the technique will improve patient outcomes.

Its significance is that it gives scientists another tool for investigating a complicated question: how do cancer cells acquire characteristics that may help them survive and contribute to a tumor's return?

Sometimes a breakthrough does not begin with a new drug. It begins with a better way to reproduce a biological problem in the laboratory — so that researchers can study it, understand it, and eventually discover how to address it.