Scientists have created what is effectively a "cluster bomb" that targets cancer. The new treatment delivers the chemotherapy drug cisplatin with the help of tiny nanoparticles.
"The negative side effects of cisplatin are a long-standing limitation for conventional chemotherapy," said Jinzhi Du, one of the researchers. "In our study, the delivery system was able to improve tumor penetration to reach more cancer cells, as well as release the drugs specifically inside cancer cells through their size-transition property."
In this latest study, the researchers used nanoparticles that enhanced cisplatin drug accumulation in tumor tissues. The particles themselves start out relatively large at 100 nanometers wide. This allows them to smoothly transport into the tumor through leaky blood vessels. When they encounter acidic conditions close to tumors, though, these particles release tiny "cluster bombs" of nanoparticles that are just 5 nanometers in size. Cisplatin itself works by crosslinking and damaging DNA inside tumor cells.
In order to test this method, the researchers gave mice bearing human pancreatic tumors this treatment. The scientists found that when the mice were given the same doses of free cisplatin or cisplatin clothed in the nanoparticles, the level of platinum in tumor tissues was seven times higher with the nanoparticles.
In addition, the researchers found that the nanoparticles were actually effective against a cisplatin-resistant lung cancer and an invasive metastatic breast cancer model in mice.
So what does this mean? The nanoparticles make the treatment far more effective. Not only that, but it could be that nanoparticle delivery of just a limited dose would limit adverse side effects from the treatment. Adverse side effects can include toxic effects to the kidneys, nerves and inner ear.
The new method could be huge when it comes to helping patients with cancer. With that said, this method has only been tested in animals. It could be quite some time before it will be transferred into humans. However, the current findings are optimistic. If the researchers are able to refine this method, it could be a huge boon for patients in the future.
The findings are published in the March 2016 journal Proceedings of the National Academy of Sciences.