Diamonds - A cancer patient's best friend
Diamonds have long been recognised as a girl’s best friend. But now a European Union (EU)-funded research project has demonstrated that the unique properties of diamonds extend far beyond that legendary sparkle. They also offer a radical new way to detect the onset of cancer far earlier than has previously been possible – opening up the possibility of more effective treatment and potentially saving the lives of countless cancer patients.
It was to address this challenge that DINAMO, a three-year project bringing together partners from Belgium, the Czech Republic, Germany, the US and Australia, was established in 2010. The key challenge facing the consortium was that all previous attempts had failed because it had proved impossible to find a way of monitoring processes within living cells for any extended period of time which did not in itself disrupt normal cellular function.
The DINAMO consortium focused on developing an entirely novel technique based on the use of tiny pieces of diamond known as nanodiamond particles (NDPs). The team successfully demonstrated that the specific combination of properties found in diamonds made NDPs a highly suitable material for the construction of probes capable of sensing biomolecules ranging from proteins to DNA. Such probes could be used to study molecular processes in cells at the nano scale.
First and foremost, the small size of the NDPs enables them to penetrate individual cell membranes in a non-invasive way which causes no damage to the cell. Equally importantly, NDPs are ‘biocompatible’ – in other words, they can remain for prolonged periods inside cells without influencing any cellular mechanisms.
On top of this, NDPs can be engineered so that they possess a range of unique optical, electrical and surface properties which mean that, once in place within the target cell, the probe is able to detect, and relay information about, the processes taking place in individual cancer cells. As DINAMO’s project co-ordinator, Professor Milos Nesladek, Strategic Research Manager Material Physics at Belgium-based research institute IMEC, explains, these ‘engineered’ properties include both luminescence and certain magnetic qualities.
“This is one of the beauties of the story,” says Professor Nesladek. “Both the luminescence and the magnetic properties change depending on the NDP’s interaction with the cellular environment, providing us with information on the processes that are occurring there, probe that is being developed at the University of Stuttgart in Germany.
In addition, collaborative research between the Julius Maximilians Universitaet Wuerzburg in Germany and the Academy Science of the Czech Republic has demonstrated that the surface properties of the diamond particles are such that they can be treated in a way which makes it possible to attach specific biomolecules to them, such as primary DNA molecules. Delivered precisely to the target cell, these biomolecules can measure, monitor or even alter biological components within the cell. The NDP thus becomes not only a tool to monitor and detect pre-cancerous changes, but also potentially to rectify them.
“Taken together, this combination of properties make NDPs unique in their ability not only to track and provide images of cellular processes and biomolecular events, but also to achieve the precisely targeted delivery of specific biomolecules for potentially therapeutic as well as monitoring purposes,” says Professor Nesladek.
So far, the DINAMO project has focused on the use of NDP probes in the context of breast cancer and colorectal cancer, but there is no reason, says Professor Nesladek, why the technique could not be applied more generally to a wide range of other cancers. Experiments at Northwestern University in the US have already shown that using NDPs to deliver anti-cancer treatments to tumours both reduces the toxic side-effects associated with existing drugs, while also resulting in more effective treatment.
But the story need not stop even there. One of the key remaining aims of the DINAMO project, says Professor Nesladek, is to explore the possibility of using NDP probes to detect cancer stem cells. These are the cells that are believed to lie at the heart of cancers and drive the re-growth of tumours after initial treatment. To date, no diagnostic method for detecting these cells exists.