Cannabis as a possible treatment for lung cancer
April 17, 2007
Jonathan M. Gitlin, Arstechnica
More news from the American Association for Cancer Research's annual meeting today (although perhaps I should have waited to run it on Friday). Yesterday, I covered research that might bring about an effective therapy for pancreatic cancer, today the topic is that other feared disease, lung cancer.
As with pancreatic cancer, lung cancer is difficult to detect until it's fairly well-advanced and can be very resistant to treatment. A very rare disease before the first World War, the massive growth in tobacco smoking since then has seen a huge increase in the prevalence of this disease, mainly fueled by inhaling carcinogenic tar and smoke into the lungs.
Here's where the story gets interesting. Cannabis is also chiefly administered via smoking and yet doesn't seem to cause lung cancer at nearly the same rate. Now a team of researchers at Harvard have identified an anti-cancer potential for one of the active ingredients in cannabis, delta-tetrahydrocannabinol (THC).
THC acts on pair of receptors, CB1 and CB2. The receptors are found in the brain and peripheral tissues; CB1 activation in the brain is responsible for the psychoactive effects of the drug, CB1 activation in the circulation causes a decrease in blood pressure, and CB2 is involved in modulating immune function.
It has also been noted that CB1 and CB2 receptors are present in biopsy samples from lung cancer patients and from lung cancer cell lines. In this current study, the researchers found that treatment with THC inhibited growth in these cell lines, and also reduced tumor size and weight in a mouse model of lung cancer.
Cannabis has previously been used by chemotherapy patients to combat nausea, but this suggests that one day we might be using the drug to fight cancer itself.