Many people will tell you that smoking cannabis (aka marijunana, the world’s most famous ‘pot plant’) is bad for you. Another reason to avoid the hallucinogenic plant is provided by work of an international team of immunologists who have discovered that marijuana may trigger a suppression of the body’s immune functions. Working with mice, Venkatesh Hegde et al. (European Journal of Immunology 40: 3358–3371, 2010) found that injected cannabinoids – including the best-known one, THC (delta-9 tetrahydrocannabinol) – can trigger a massive number of myeloid-derived suppressor cells (MDSCs). MDSCs, which actively suppress the immune system, increase in cancer patients and it is believed that they may suppress the immune system against cancer therapy, actually promoting cancer growth. So, although THC may bring pain relief in some medical applications, it could immuno-compromise in other instances with attendant cancer risk. Please remind Frank to say ‘No, thank you’ to drugs!
Aspirin, one of the most famous plant-derived medicines, is often used as an analgesic (to relieve minor aches and pains), as an antipyretic (to reduce fever), and as an anti-inflammatory. Added to this impressive list is a potential new role in reducing the risk of cancer, according to work by Peter Rothwell and colleagues (The Lancet 377: 31–41, 2011). The study – which covered some 25,000 patients, mostly from the UK – found that a small daily dose of aspirin substantially reduces death rates from a range of common cancers; patients who were given aspirin had a 25% lower risk of death from cancer during the trial period (and a 10% reduction in death from any cause) compared with patients who were not given the drug. The benefit in cancer reduction was found from a low daily dose of 75 mg. Aspirin is already known to cut the risk of heart attack and stroke among those at increased risk, but the protective effects against cardiovascular disease are thought to be small for healthy adults, and aspirin increases the risks of stomach and gut bleeds. But the latest findings suggest that aspirin’s benefits often outweighed its associated risk of causing bleeding in older individuals. However, this doesn’t mean that aspirin will counter any negative effects of taking marijuana!