The findings were presented at the annual meeting of the American Association for Cancer Research.
The finding builds on the recent discovery of the body’s own cannabinoid system, Preet says. Known as endocannabinoids, the natural cannabinoids stimulate appetite and control pain and inflammation.
THC seeks out, attaches to, and activates two specific endocannabinoids that are present in high amounts on lung cancer cells, Preet says. This revs up their natural anti-inflammatory properties. Inflammation can promote the growth and spread of cancer.
In the new study, the researchers first demonstrated that THC inhibited the growth and spread of cells from two different lung cancer cell lines and from patient lung tumors. Then, they injected THC into mice that had been implanted with human lung cancer cells. After three weeks, tumors shrank by about 50%, compared with tumors in untreated mice.
Paul B. Fisher, PhD, a professor of clinical pathology at Columbia University, says that though the work is “interesting,” it’s still very early.
“The issue with using a drug of this type becomes the window of concentration that will be effective. Can you physiologically achieve what you want without causing unwanted effects?” he tells WebMD.”