A key line of treatment for many cancers is surgery, but frustratingly, this doesn’t always get rid of the disease. Once a tumor has been removed, it can return, and the cancer can spread to other parts of the body. Now, scientists have found a way to potentially stop this from happening, all thanks to a simple spray-on gel.
Publishing their results in the journal Nature Nanotechnology, a team from UCLA tested the gel on mice whose advanced melanoma tumors had been removed through surgery. They found that it reduced regrowth of the original tumor, which in turn helped to prevent the cancer from popping up elsewhere.
So, how does it work?
Rather than actively attacking the cancer cells, the gel actually works by boosting the patient’s immune system. Cancer cells release a protein called CD47, which basically tells the body not to attack the tumor. The new spray-on gel contains an antibody that blocks this protein, allowing the body’s immune system to identify and kill the cancerous cells.
The antibodies are loaded onto tiny nanoparticles made from calcium carbonate. Calcium carbonate is a key ingredient of eggshells and dissolves in surgical wounds as they are slightly acidic. As it dissolves, it slowly releases the antibodies into the wound. It also boosts the activity of a type of immune cell called a macrophage, which detects and kills unwanted cells by eating them.
The researchers also discovered that their gel could activate another important immune cell called a T cell, enhancing the body’s response to the cancer even more. According to lead author Qian Chen, this provided "another line of attack against lingering cancer cells."
However, it’s important to remember that so far, the new spray has only been tested on mice, not people. More research is needed before it can be clinically tested in human patients to see if it actually works. Still, the results are certainly promising, with half of the mice surviving for at least 60 days without any cancer regrowth.
"This sprayable gel shows promise against one of the greatest obstacles in curing cancer," Zhen Gu, who led the research team, said in a statement. "One of the trademarks of cancer is that it spreads. In fact, around 90 percent of people with cancerous tumors end up dying because of tumor recurrence or metastasis. Being able to develop something that helps lower this risk for this to occur and has low toxicity is especially gratifying."