Imaging and treating cancerous tumors simultaneously

Simultaneously visualizing and treating a cancerous tumor could soon be within reach thanks to a promising innovation developed by chemists, biophysicists, and biologists from CNRS.

In an article published in PNAS, scientists present self-assembling nanosystems that enable the precise imaging of a tumor via fluorine magnetic resonance while simultaneously delivering a targeted anti-cancer agent.


Theranostics is an emerging field in medicine that combines diagnosis and therapy into a single integrated approach. It aims to personalize and optimize medical treatments by using agents and technologies capable of simultaneously diagnosing a disease and treating it, while also allowing for real-time monitoring of the treatment's effectiveness.

In this context, fluorine magnetic resonance imaging, known as MRI-¹⁹F, is a highly precise biomedical imaging technique that uses fluorine to generate images. Unlike the proton, which is the basis of most clinical MRI exams, fluorine is absent from most biological systems, enabling the unambiguous detection of administered fluorinated molecules and high specificity in imaging their sites of accumulation. However, its usage has been limited thus far by the lack of safe, water-soluble imaging agents containing a large amount of fluorine.


Scientists from the Interdisciplinary Center of Nanoscience of Marseille (CNRS/Aix Marseille University), the Center for Biological and Medical Magnetic Resonance (CNRS/Aix-Marseille University), and the Cancer Research Center of Marseille (CNRS/INSERM/Aix-Marseille University/Paoli-Calmette Institute) have recently developed amphiphilic dendrimers that could overcome these obstacles and develop innovative imaging agents for MRI-¹⁹F.

These molecules, which combine fluorinated sections at the ends of hydrophilic dendrons with hydrophobic segments, were designed to self-assemble into supramolecular nanomicelles with the fluorinated entities exposed on the surface. Negatively charged carboxylate groups also present on the micelle surface prevent the aggregation of fluorinated entities through electrostatic repulsion.

This strategy allows the transport of fluorinated nuclei through the body, leading them directly to the tumor, which is detected using MRI-¹⁹F.

But that's not all: these self-assembling nanosystems can also be used to encapsulate and deliver multiple compounds in the body. For example, a near-infrared fluorescent (NIRF) agent and an anticancer drug like paclitaxel. The scientists selected these two compounds to precisely visualize the tumor using multimodal imaging (MRI-¹⁹F and NIRF) and to initiate in situ its theranostic treatment.

In studies on mice with human pancreatic cancer xenografts, these agents not only specifically visualized the tumors but also demonstrated superior efficacy compared to paclitaxel alone in treating the cancer.


These results open new perspectives for the design of MRI-¹⁹F agents and theranostic treatments. By leveraging the self-assembling supramolecular dendrimer chemistry, this work could lead to significant advances in cancer management and other diseases requiring precise imaging and targeted treatments.

The next steps will be to refine this technology and conduct clinical trials to evaluate its efficacy and safety in humans.

Editor: AVR

Reference:
Self-assembling dendrimer nanosystems for specific fluorine magnetic resonance imaging and effective theranostic treatment of tumors
PNAS 2024