One of the key challenges for the treatment of brain tumours is the blood-brain barrier (BBB), a membrane which protects the brain from harmful substances. Unfortunately, this also prevents a lot of drugs from accessing the sites of brain tumours. Further insight into the role of the blood-brain barrier is particularly important in the development of new therapies, as our Director of Research explains in his recent article in Oncology News.
One potential approach is the “packaging” of drugs with carrier agents which will allow them to cross the BBB. The Ohio State University Comprehensive Cancer Centre is one of four cancer centres in the U.S. involved in testing a new "nanomedicine" agent – known as BXQ-350 – in advanced solid tumours, including difficult-to-treat high-grade brain tumours.
BXQ-350 combines a protein called Saposin C, which is naturally expressed in humans, with nanobubbles of a fat molecule called DOPS. This combination creates a treatment agent that has the ability to penetrate the blood-brain barrier and also selectively target and kill cancerous tumour cells, largely sparing the surrounding healthy tissues. This medicine may be particularly useful against high-grade brain tumours which do not respond to existing therapies.
"BXQ-350 is the first agent in this class of drugs and has unique properties not seen in conventional cancer treatments. It is made of natural substances present in humans. Lab experiments have shown the agent has the ability to target cancer cells specifically and ultimately eliminate them," says Vinay Puduvalli, MD, one of the lead researchers in the study.
Results from an early phase clinical trial show that the agent is well tolerated by patients with few reported side effects. The next stage trial is currently currently recruiting additional patients in centres within the US. The results demonstrate that research can potentially open new doors to the treatment of high-grade brain tumours and other advanced cancers.
Research is also being carried out at our Centre of Excellence at the University of Portsmouth, where they have developed a model of the BBB and are using it to investigate the use of other agents, such as nanoparticles, to help drugs to cross into the brain to access the tumour site and kill the cells.