By Emily Ledger
For decades, advocates of medicinal cannabis have pointed to the plant’s potential anti-cancer properties. In recent years, governments around the world, including in the UK, have begun to allow the use of medicinal cannabis products for the treatment of a limited number of conditions. However, cannabis products may only be prescribed for chemotherapy-induced nausea in relation to cancer.
Now, evidence published by the University of Newcastle in Australia has revealed new findings into the plant’s anti-cancer potential. The tests carried out at the University and the Hunter Medical Research Institute showed that a modified form of cannabis had the potential to kill or inhibit cancer cells. In addition, the high-CBD form of cannabis did not impact other natural cells.
A low-THC form of the cannabis plant known as ‘Eve’, produced by Australian Natural Therapeutics Group was tested by cancer researcher Dr Matt Dun at the New South Wales university. The cannabis variety is high in CBD and contains less than 1% THC.
Past evidence has suggested that THC – the most prevalent cannabinoid found within the cannabis plant – was the main source of the plant’s potential anti-cancer properties. However, the lab tests carried out in collaboration with the Australian Natural Therapeutics Group, revealed that strains high in CBD may be more effective at killing cancer cells.
Dr. Matt Dunn, explains how researchers have been testing the potential of cannabis in the treatment of cancer over the last three years:
“We initially used leukaemia cells and were really surprised by how sensitive they were. At the same time, the cannabis didn’t kill normal bone marrow cells, nor normal healthy neutrophils [white blood cells].”
After initial tests, the researchers became aware that the drug appeared to have a cancer-selective mechanism. Strains of cannabis that lacked high levels of psychoactive cannabinoid THC were actually found to be more effective at killing cancer cells associated with leukemia and paediatric brainstem glioma.
Other trials that have been carried out around the world have revealed that high-THC cannabis may help with symptoms of cancer. In particular, cannabis has been identified as having the ability to improve quality of life for patients suffering from chemotherapy-induced nausea.
However, Dr. Dunn explains that high-THC cannabis may also have some setbacks for some patients:
“You can’t drive, for example, and clinicians are justifiably reluctant to prescribe a child something that could cause hallucinations or other side-effects. The CBD variety looks to have greater efficacy, low toxicity, and fewer side-effects, which potentially makes it an ideal complementary therapy to combine with other anti-cancer compounds.”
The next phase of research in the area will aim to understand what makes cancer cells vulnerable while other cells appear not to be. Researchers will assess whether this is clinically relevant and whether it is reflected in other kinds of cancer.
*Research into the anti-cancer properties of the low-THC cannabis strain is being funded by the producers of the product (Australian Natural Therapeutics Group).