CBD could help stop the growth of intractable brain cancer in both humans and dogs, according to a new study conducted by Colorado State University (CSU).
In a new study that has yet to be fully published, researchers investigated the effects of medical cannabis on glioblastoma, a deadly form of brain cancer. Survival rates for this form of cancer — which affects humans, as well as dogs — are extremely low, and traditional cancer treatments have had limited success in stopping the growth of these tumors.
"Further research and treatment options are urgently needed for patients afflicted by brain cancer," said Chase Gross, a student at CSU's Doctor of Veterinary Medicine/Master of Science program, in a statement. "Our work shows that CBD has the potential to provide an effective, synergistic glioblastoma therapy option and that it should continue to be vigorously studied."
In their experiment, CSU researchers grew human and canine glioblastoma cells in a cell culture and exposed them to two different CBD extracts. One of these extracts was 100 percent pure CBD isolate, and the other was a naturally-derived CBD extract that contained trace amounts of CBG, THC, and other cannabinoids.
Researchers found that CBD killed human and canine glioblastoma cells and also slowed their overall growth. Both the CBD isolate and the extract had similar rates of success. During the experiment, researchers observed that CBD caused the cancer cells' intracellular vesicles to swell. After this swelling, the cells' membranes began to bulge and eventually break down, killing the cells.
The current study will join a growing body of research studies suggesting that CBD and other cannabinoids can help fight various forms of cancer. An Israeli study from last year found that whole-plant cannabis extracts can promote the death of cancer cells. Another recent research review found that synthetic or natural cannabis extracts have helped treat brain, blood, oral, breast, and prostate cancers. Other studies have found that other cannabinoids like CBG and CBC, as well as cannabis flavonoids, can also have cancer-fighting effects.
Scientists don’t know exactly how the anti-cancer effects of cannabis work, but the present study suggests that CBD can damage cancer cells' mitochondria, the structures that produce energy for the cell. The experiments found that cells treated with CBD showed significant decreases in mitochondrial activity before finally breaking down entirely.
"CBD has been zealously studied in cells for its anticancer properties over the last decade," Gross explained in the statement. "Our study helps complete the in vitro puzzle, allowing us to move forward in studying CBD's effects on glioblastoma in a clinical setting using live animal models. This could lead to new treatments that would help both people and dogs that have this very serious cancer."
The present experiment is only the first stage in a long-term project that may take up to 15 years to complete. For the next step, researchers will move on from cell cultures and begin testing CBD on animal models. If these trials are successful, researchers at CSU's Veterinary Teaching Hospital could begin clinical trials on dogs that are suffering from glioblastoma. From there, researchers could then begin testing the effects of CBD on human brain cancers.
Gross was due to present the findings of this new research at the American Society for Pharmacology and Experimental Therapeutics annual meeting in San Diego this month, but the event was cancelled due to the ongoing coronavirus pandemic. An abstract of the study was published in this month's issue of The FASEB Journal, but the full study has not yet been released.