Recent developments in molecular imaging
Imagion Biosystems demonstrates that anti-HER2 iron oxide nanoparticles can be used for image-based diagnosis and treatment monitoring by both SPMR and MRI
MELBOURNE | 9 SEPTEMBER 2019
A new set of data presented by Imagion Biosystems, a company specialising in the emerging field of nanobiotechnology, makes it possible to detect elusive HER2 breast cancer cells.
HER2, human epidermal growth factor receptor 2, is a gene that can play a role in the development of breast cancer. The HER2 gene codes for HER2 proteins, which usually regulate a range of breast cell metabolic processes, namely cell growth, cell division and tissue repair. However, in about one fifth of breast cancer cases, the HER2 gene is unable to function correctly, leading to HER2 protein overexpression which causes breast cells to grow and divide in an uncontrolled manner. HER2-positive breast cancers tend to be more aggressive than other types of breast cancers, are more likely to recur than other forms of HER2-negative cancer, and has the potential to significantly impact treatment recommendations and decisions.
A recent study by Imagion Biosystems aimed to demonstrate the potential imaging utility of superparamagnetic iron oxide nanoparticles (SPION) for detecting HER2 positive breast cells. This study produced the company’s first reported results which show that SPION nanoparticles are able to achieve dual function – of being able to provide specific targeting of cancer cells in Imagion’s MagSense™ technology as well as become a multi-modal molecular imaging agent in magnetic resonance imaging (MRI). The results of the study were organised in a poster form and presented at the 2019 World Molecular Imaging Congress that was held in Montreal, Canada earlier this month.
Previously, SPION were only utilised in the company’s trademark technology, MagSense™ -- a technology based on superparamagnetic relaxometry (SPMR) – that aims to facilitate the early detection of various types of cancers. SPMR is a highly sensitive detection technology that is able to differentiate the magnetic signature of nanoparticles bound to tumour cells and from unbound nanoparticles. Nanoparticles that reach and bind to the target cells act as a magnetic beacon and are detectable by MagSense™ sensors. A spatial contour map of the magnetic field distribution determines the location of the source in three dimensions as well as the magnetic moment, achieving unprecedented levels of in vivo tumour detection sensitivity with tumour type specificity. As an additional benefit, SPMR technology entails fewer risks as it uses very low magnetic fields, and is less expensive to manufacture and install.
The study has found that the MagSense™ nanoparticles may be equally effective as a multi-modal molecular imaging agent in MRI. It has been noted that an effective in vivo functional imaging tracer or imaging agent must be able to provide both specificity and sensitivity. The nanoparticles’ ability to target carcinogenic elements in the human body showcases its precision, and its ability to provide contrast based on varying tissue depth for MRI scans demonstrates its sensitivity. Together, these factors allow for the MagSense™ nanoparticles to achieve diagnostic utility as a molecular imaging modality.
“This study provides further evidence and insight into the effectiveness of our nanoparticles and their ability to specifically bind to targeted tissue, where they then act as a magnetic tag or beacon and a non-invasive imaging tool,” Said Bob Proulx, CEO of Imagion Biosystems.
Indeed, the implementation of this new technology could possibly fill up a large vacuum in the MRI technologies in commercial hospitals. Usually, imaging agents injected intravenously into the patient’s body before the MRI scan only have one purpose – to enhance image quality and improve image resolution. These imaging agents are only able to create contrast at tissue boundaries and are unable to achieve functional imaging utility.
A targeted MagSense™ nanoparticle detectable by SPMR that could also be used as a contrast agent to enhance MR image of specific tissue would create an opportunity for Imagion to work with the large installed base of existing MRI machines already in hospitals. “While development of our proprietary magnetic relaxometry technology has been our focus to date, this new preliminary work shows the potential for our MagSense™ nanoparticles to work with MRI and could open up a new commercial pathway as an contrast agent that can be used to improve the effectiveness of MRI in the detection and monitoring of HER2 breast cancer.” Mr Proulx noted.
These studies lay out groundwork for early and metastatic breast cancer tumour detection as well as monitoring therapy response. Moving forward, Imagion Biosystems plans to embark on more in-depth studies to explore how their technology could be optimally positioned alongside existing clinical practices to enhance its commercial potential.
The poster for the study was presented at the World Molecular Imaging Congress by Dr Marie Zhang, VP of Research and Pre-Clinical Development at Imagion Biosystems.
This article was contributed by Michelle Tan Min Shuen, an editorial intern at World Scientific Publishing Co. and a contributing writer for Asia-Pacific Biotech News. She is from Nanyang Girls' High School, has a keen interest in chemistry and the life sciences, and pursues taekwondo in her free time.