By Gianluca D’Elia
Researchers from the Robert Wood Johnson Medical School at Rutgers University have been analyzing the dispersal of tumor cells, hoping to slow down the spread of a highly malignant brain tumor, glioblastoma.
Ramsey Foty, an associate professor at Rutgers, discussed the theories, methods and results of the university’s work on Friday, Feb. 17, as part of Rider’s Science Friday series, which features speakers from chemistry, astrophysics, biology and Earth sciences twice a month.
“Most people with glioblastoma don’t live past three years,” Foty said. “This disease is difficult to treat because a lot of chemotherapy can’t cross the blood-brain barrier.
“Tumor cells, like stem cells, are resistant to conventional chemotherapy,” he explained. “They have pumps in their cell membranes that detect drugs and spit them back out.”
Furthermore, the brain is susceptible to damage, making the treatment of the disease even more complicated.
“Even if you could find a drug that could cross the blood-brain barrier, the brain doesn’t like having a lot of toxins in it,” he said. “The brain has a limited capacity for self-repair.”
There is also a limit to the “surgical margins” when it comes to brain surgeries, Foty said.
“You have a limited amount of tissue you can remove before you start causing problems for the patient.”
Because of complications like these, treatment options for glioblastoma are limited.
“Glioblastoma comes back 100 percent of the time,” Foty said. “Long-term, disease-free progression is practically impossible. You can’t remove as much as you need to remove to get every single tumor cell because 95 percent of them recur at the site of the original lesion or 2 to 3 centimeters from the surgical border.”
Foty and other researchers applied multiple methods to decrease the velocity at which tumor cells would spread, by making the cells more cohesive and keeping them glued together, so they don’t “crawl through the spaces between normal cells,” Foty said.
The process of studying tumor cells, which often involves testing on mouse brains, is what Rider biology professor Jonathan Yavelow describes as a model system.
“If you could take the cells from a tumor, put them in a dish and find ways to kill them — that’s an example of a model system,” Yavelow explained. “And this sounds yucky, but if you could take a slice of brain and put it in a sterile dish, and then put the cancer cells on top of it and look at creative ways to kill it, that would be an even better example — this use of model systems is very elegant.”
By limiting the dispersal of the tumor cells, it may be possible to delay the recurrence of glioblastoma after chemotherapy. There is no known cure, so the best scientists can do for now is find ways to make the disease’s recurrence easier to deal with, Foty told students.
“The idea behind it is to push people as far out as the [tumor’s] recurrence can hold off,” Foty explained. “It’s not a cure, but it’s at least a control. Anything can happen in that time frame — maybe other scientists will develop a new immunology drug — but the whole point is to keep patients as healthy as possible, for as long as possible until the disease gets them.”
The most ideal drug for treating the recurrence of glioblastoma tumor cells, according to Foty, would be one that is safe, efficient, selective about which cells it kills, able to cross the blood-brain barrier and has low side effects. The drug that meets this criteria the most is one called dexamethasone, and even dexamethasone has its problems — it causes side effects after prolonged use, and it is not selective, which means it would attack other cells in the body the way it is supposed to attack cancer cells.
Senior biology major Robert Raggi said, “I loved learning about new techniques in how to address a serious situation. When you think of drugs, you think of using a certain drug to cure a disease, but instead they’re using this drug to contain.”
“The tragedy of glioblastomas, unfortunately, is mostly known in the families who have people suffering,” Yavelow added. “Any increase in life with such a wonderfully-tolerated drug as dexamethasone would be very welcomed.”