Researchers at the University of Newcastle have found that a modified version of medicinal cannabis can kill and inhibit cancer cells without impacting normal cells.
The research comes after a three-year collaboration between cancer researcher Dr. Matt Dun and biotech company Australian Natural Therapeutics Group (ANTG). Throughout the period, Dun and his team tested the company's cannabis strain with less than 1% tetrahydrocannabinol (THC), the psychoactive compound in cannabis, against cancer.
During their research, Dun and his colleagues tested THC-rich cannabis against varieties with higher levels of cannabidiol (CBD). In the end, they found that those rich in CBD tended to be more effective in killing cancer cells from leukemia and pediatric brainstem glioma than high-THC varieties. More than this, they found that low-THC and high-CBD varieties did not kill normal bone marrow cells or healthy white blood cells.
The team also released a literature review of more than 150 academic papers investigating the anti-cancer effects of CBD and THC. In total, they concluded that high CBD varieties tend to be more effective and have lower toxicity and fewer side effects. Dunn said that it might, therefore, be an ideal complementary therapy for other anti-cancer compounds.
The researchers now aim to study why cancer cells are sensitive to CBD and normal cells not. They also want to uncover the clinical relevance of CBD treatment and how many cancers respond.
"We need to understand the mechanism so we can find ways to add other drugs that amplify the effect, and week by week, we're getting more clues. It's really exciting and important if we want to move this into a therapeutic," says Dr. Dun.
Although CBD-enriched cannabis isn't yet clinically approved to treat cancer, Dun hopes that his research will lessen the stigma around cannabis treatments in the future.