Scientists have developed a new bio-nanocomposite which they hope can help diagnose and treat breast cancer in the future. Credit: Dreamstime
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One in eight women will develop breast cancer during their lifetime, making it the most common cancer in the UK. If caught early, treatment options are positive. Unfortunately this type of cancer can spread to other places in the body, such as bones, which increases morbidity. But suppose you could engineer an army of biological nano-soldiers? Using magnetic navigation to guide them to breast tissue, they could use in-built technology to find, engage and fight breast cancer cells. Sounds impossible? Well, a collaboration between scientists from Denmark, Brazil, Germany and the UK have developed a new bio-nanocomposite which they hope, with more research, will be able to do just that!
Current detection methods, such as x-ray mammography, only detect between 65% and 95% of cancers. Imaging techniques, such as MRI, which has a higher detection rate, are not very reliable due to the presence of false positives. Therefore a more efficient detection and drug delivery system for breast cancer diagnosis is a priority.
Fortunately, cancer cells have an affinity for hydroxyapatite, a major component of bone tissue; a molecule which has been shown to reduce metastatic activity. In light of this, scientists have developed a new delivery system that capitalises on such an attraction.
The team has synthesised magnetic nanoparticles coated with a biocompatible polymer; the polymer itself is modified to include nanocrystals of hydroxyapatite. Such a system will give a higher contrast on MRI scans; the magnetic nanocomposites detecting and flagging the cancer cells by binding to them. However not only can these nanocomposites aid diagnostics but they also have the potential to treat the cancer since apatite has been shown to have an inhibitory effect on breast cancer cells. Furthermore these nanoparticles have the potential to act as a drug delivery system by carrying with them anticancer drugs and directing them to the specific tumour sites. A further advantage comes from the magnetic structure of the nanocomposite, which offers the possibility to direct them to the breast cancer tissue using external magnets.
The team used neutron diffraction to assess the ionic distribution in the nanoparticles. To do this they used the POLARIS instrument at ISIS. Murillo Martins, University of Copenhagen, explains “It is very important to tune the magnetic properties of our material depending on its final application. To do so, one of the parameters that must be controlled is the ionic distribution along the magnetic nanoparticle´s microstructure. The neutron powder diffraction data showed that all the Zn ions, which have no magnetic moment, are in the tetrahedral sites of the nanoparticles. It is an important result because such ionic distribution provides the highest magnetic saturation to the nanoparticles and, therefore, a lower amount of material will be required to generate the contrast signal needed for both diagnosis purposes and to carry an anti-tumour drug.”
Neutron scattering allows us to look deep into matter without destroying it. The technique gives insights into the dynamics and local geometry of the motions of confined molecules. Neutrons can also tell us about the distribution of atoms in a lattice and the magnetic orientation of those atoms. According to Heloisa Bordallo, Murillo’s supervisor at the University of Copenhagen, “This is just the information needed” to demonstrate that Murillo’s idea, of encapsulating a drug in a delivery system, works.
Scanning Electron Microscopy (SEM) of the bio-nanocomposite.
The next step is to incorporate an anti-tumour drug into the material to enhance its effectiveness against breast cancer. Neutrons will be able to ‘see’ if the drug is really encapsulated, and more importantly, if encapsulation changes its three dimensional structure. In the meantime, the first in vitro assays with cancer cells are being performed.
Murillo explains, “This publication is a tiny, but important, step toward achieving our final goal. A lot of experimental work is still needed, but we are getting there. In the beginning people were sceptical, now they are starting to understand the general idea. At the end, a lot of perseverance, the possibility to work in an open environment and access to facilities like ISIS, where you can get support and be exposed to a good scientific environment, is the key.”
Collaborative partner and ISIS research scientist, Mark Telling, said “It is still very early days. I see a future fraught with trial and error, many more neutron studies and a lot more inter-disciplinary research needed to be done. However, this work demonstrates the potential for this type of drug delivery vehicle and that is very exciting.”
Felice Laake and Mark Telling
Murillo Martins et al.
Research date: October 2013
Murillo L. Martins, Margarida Juri Saeki, Mark T.F. Telling, Joao P.R.L.L. Parra, Sven Landsgesell, Ron I. Smith, and Heloisa N. Bordallo. Development and characterization of a new bio-nanocomposite (bio-NCP) for diagnosis and treatment of breast cancer. Journal of Alloys and Compounds. (2014). 584, 514-519.
For further information please contact Dr Mark Telling
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