2 October 2015
Described as potentially ‘the best cloaking mechanism yet’ a novel method of disguising cancer drugs as blood cells is being tested on mice and showing exciting results.
Camouflaging therapeutic drugs, particularly cancer drugs, is important. The body’s immune system often recognises the alien drug molecules as a threat and sets about destroying them. The current lifespan of a cancer drug in the body is about six hours. Indeed cancer drugs often are a threat to any healthy tissue they come into contact with, hence the debilitating side effects for which they are notorious.
What is most exciting about this research is that, because cancer cells need blood platelets in order to thrive, they naturally attract the platelets to them. Furthermore, because this technology, developed by scientists at University of North Carolina, uses a patient’s own platelets, the team believe the drugs can be transported to the target sites without alerting the immune system.
The approach uses two anti-cancer drugs, Dox and TRAIL. The platelet membranes are extracted from the platelet and then coated first with a nanoscale gel containing the anti-cancer drug Dox. The solution is then compressed to create spheres comprising platelet membranes with Dox-gel cores. These spheres are given a coating of TRAIL which is particularly effective at attacking the membranes of cancer cells. This second coating keeps the pseudo platelet circulating around the bloodstream for up to 30 hours – five times longer than the average cancer drugs. The pseudo platelet in this time targets the primary tumour, but also attacks cancer cells that are in the bloodstream before they take hold in other tissue.
So far the technology has been tested in mice, but it seems to offer an exciting proposition for directly targeting drugs to where they are needed. Whether this approach works better than alternatives where drugs are masked in order to mimic viruses or bacteria is unclear. The North Carolina scientists will be working to find this out in future studies. They also hope to investigate how this approach might be used for other conditions, specifically heart disease.