Some tumors are hard to find, while others are hard to destroy. Fortunately, a new research study from the University of California, Davis, has developed a new type of nanoparticle that could one day do both.
Reporting in the latest issue of Nature Communications, researchers in the laboratory of UC Davis’ Dr. Kit Lam describe a type of ‘dynamic nanoparticle’ that they created, which not only lights up tumors during an MRI or PET scan, but which may also serve as a microscopic transport vehicle, carrying chemotherapy drugs through the blood stream—and releasing them upon reaching the tumor.
This is not the first time scientists have attempted to develop nanoparticles for medicinal purposes, but is perhaps one of the more successful. As Yuanpei Li, one of the study’s co-first authors stated in a news release:
“These are amazingly useful particles. As a contrast agent, they make tumors easier to see on MRI and other scans. We can also use them as vehicles to deliver chemotherapy directly to tumors.”
Nanoparticles can be constructed out of virtually any material—but the material used often determines for what purpose they can be used. Nanoparticles made of gold-based materials, for example, may be strong for diagnostic purposes, but have been shown to have issues with safety and toxicity. On the flip side, nanoparticles made from biological materials are safer, but inherently lack imaging ability. What would be great, the team reasoned, was a new type of nanoparticle that had the best qualities of both.
In this study, which was funded in part by CIRM, Lam and the UC Davis team devised a new type of nanoparticle that was ‘just right,’—simple to make, safe and able to perform the desired task, in this case: attack tumors.
Built of organic porphyrin and cholic acid polymers and coated with the amino acid cysteine, the 32 nanometer-wide particles developed in this study offer a number of advantages over other models. They are small enough to pass into tumors, can be filled with a chemo agent and with a specially designed cysteine coating, and don’t accidentally release their payload before reaching their destination.
And this is where the truly ingenious part kicks in. With a simple flash of light, the researchers could direct the particles to drop their payload—at just the right time, offering some intriguing possibilities for new ways to deliver chemotherapy drugs.
But wait, there’s more. The fact that these new particles, which the team are calling cysteine nanoparticles, or CNP’s, appear to congregate inside tumors means that they also end up being easy to spot on an MRI.
Continued Li in the same release:
“These particles can combine imaging and therapeutics. We could potentially use them to simultaneously deliver treatment and monitor treatment efficacy. This is the first nanoparticle to perform so many different jobs. From delivering chemo, photodynamic and photothermal therapies to enhancing diagnostic imaging. It’s the complete package.”
And while the team cautions that these results are preliminary, they open the door to an entirely new and far more exact method of drug delivery to tumors—no matter how well-hidden in the body they may be.