2023-04-24 21:00:02
A drug administered through a novel gel cured 100% of the mice with a aggressive brain cancer, a surprising result that offers new hope to patients diagnosed with glioblastoma, one of the deadliest and most common brain tumors in humans. The question is, will it work in humans?
Despite recent technological advances, there is a pressing need for new treatment strategies. “We believe that this hydrogel will be the future and will complement current brain cancer treatments,” says Cui, a chemical and biomolecular engineer at Johns Hopkins University (USA), who led the research.
Cui’s team combined an anti-cancer drug and an antibody in a solution that self-assembles into a gel to fill in the tiny grooves left after surgical removal of a brain tumor. The gel can reach areas that surgery might miss and that current drugs cannot reach to kill stubborn cancer cells and suppress tumor growth. The results were published in the “Proceedings of the National Academy of Sciences.”
The gel also appears to trigger an immune response that the mouse’s body has a hard time firing on its own in the fight against glioblastoma. When the researchers re-attacked the surviving mice with a new glioblastoma, their immune systems defeated the cancer on its own without additional medication.
According to the researchers, it appears that the gel not only repels cancer, but helps rewire the immune system to discourage recurrence through immunological memory.
Still, surgery is essential to this approach, the researchers noted. Application of the gel directly to the brain without surgical removal of the tumor resulted in a 50% survival rate.
“Surgery will likely relieve some of that pressure and give the gel more time to activate the immune system and fight cancer cells,” Cui explained.
The gel solution consists of nanometer-sized filaments made from paclitaxel, a drug approved for breast, lung and other types of cancer. The filaments serve as a vehicle to deliver an antibody called aCD47. By uniformly covering the tumor cavity, the gel consistently releases the medication for several weeks and its active ingredients remain close to the injection site.
By using that specific antibody, the team is attempting to overcome one of the most difficult hurdles in glioblastoma research. He addresses the macrophagesa type of cell that sometimes supports immunity, but other times protects cancer cells, allowing aggressive tumor growth.
One of the gold standard therapies for glioblastoma is a pill, Gliadel, which releases a biodegradable polymer after surgical removal of the tumor. Gliadel showed significant survival rates in laboratory experiments.
One of the handicaps in the treatment of patients with brain tumors and, specifically, with glioblastomas is the difficulty for the drug to reach the brain, Pilar Sánchez Gómez, head of the Neuro-oncology Unit in the Chronic Disease Research Unit (UFIEC-ISCIII). “Several years ago there were already some clinical trials using Gliadel,” he says.
Although Gliadel did not prove to be effective in patients with glioblastomas, adds Sánchez Gómez, “the great advances that have been made in understanding the biology of these tumors, together with improvements in the design of drug-release gels, allow be optimistic regarding future clinical trials.”
“We don’t usually see 100% survival in mouse models of this disease,” says researcher Betty Tyler. “To think that there is a chance that this new combination of hydrogels could change that survival curve for glioblastoma patients is very exciting.”
The new gel offers hope for the future treatment of glioblastoma because it integrates anti-cancer drugs and antibodies, a combination of therapies that the researchers say is difficult to administer simultaneously due to the molecular composition of the ingredients.
To think that there is a possibility that this new combination of hydrogels could change that survival curve for glioblastoma patients is very exciting.
“This hydrogel combines chemotherapy and intracranial immunotherapy,” explains Tyler. “The gel is implanted at the time of tumor resection, which makes it work really well.”
not so optimistic Jordi Bruna Escuercoordinator of the Neurooncology Unit of the Biomedical Research Institute of Bellvitge (IDIBELL) and researcher of the Neuroplasticity and Regeneration Group of the Autonomous University of Barcelona. Speaking to SMC: “The animal model on which the study is based is not at all representative of what a human glioblastoma is,” he warns.
And he adds that affirming that the mouse’s immune reaction to this experimental glioma is the same as that of the patient “is a more than considerable leap of faith. There is still a long way to go before the therapy they propose can be tested in patients to first assess safety and then some type of efficacy.
#gel #stops #cancer #mice #humans