Scientists at Johns Hopkins University have developed a treatment that could provide new hope for aggressive brain cancers. Injecting a drug-laden hydrogel into the brain after tumors have been surgically removed was found to launch a combined chemo- and immunotherapy attack that prevented the cancer from returning in 100% of treated mice.
Glioblastoma is one of the most common and, unfortunately, deadly brain cancers in humans. Surgery to remove it is usually the best treatment option, but frustratingly the cancer tends to return with a vengeance in most cases, leading to very low survival rates.
But the new study may offer renewed hope. The Johns Hopkins team developed a hydrogel that can be applied to the cavity in the brain left behind after the tumor is removed, slowly releasing medication over a few weeks to kill any cancer cells left behind and prevent their resurgence.
The hydrogel is made up of nano-filaments containing an FDA-approved chemotherapy drug called paclitaxel, as well as an antibody called aCD47 that helps the immune system better recognize the disease and fight back.
“This hydrogel combines both chemotherapy and immunotherapy intracranially,” said Betty Tyler, co-author of the study. “The gel is implanted at the time of tumor resection, which makes it work really well.”
The team tested the technique in five groups of mice, each containing eight individuals. A control group had their tumors removed but no hydrogel implanted afterwards, and unsurprisingly 100% of them had died within about five weeks. A second group, which received hydrogel with no drugs in it, lasted about the same time.
The third group received hydrogel loaded with paclitaxel but no antibodies, which saw a 50% survival rate. A group that received hydrogel with antibodies but no paclitaxel, meanwhile, saw a survival rate of just 25%. The fifth and final group received hydrogel with both paclitaxel and the aCD47 antibodies, and they had an astonishing 100% survival rate.
“We don't usually see 100% survival in mouse models of this disease," said Tyler. “Thinking that there is potential for this new hydrogel combination to change that survival curve for glioblastoma patients is very exciting.”
Even more encouraging results followed when the scientists later injected the mice with new glioblastoma cells, and found that the animals’ immune systems were still able to fight off the cancer, indicating a kind of vaccine effect at play.
Of course, as promising as these results look there’s still plenty of work to do before this treatment could find its way to humans. It does, however, add to a growing body of work that finds that hydrogels that slowly release drugs could be an important new therapy for various cancers.
The research was published in the journal Proceedings of the National Academy of Sciences.
Source: Johns Hopkins University