One of the main reasons cancer can be so difficult to beat is because of its ability to spread through the body, even after the primary tumor has been surgically removed. But now researchers from Vanderbilt University have developed a new technique that uses nanoparticles to enhance immune cells, helping them hunt down cancer cells migrating through the bloodstream.
Wherever it may start in the body, cancer can become exponentially more deadly once it metastasizes, spreading to other organs via the bloodstream. Frustratingly, in some types of cancer attempts to surgically remove the primary tumor can actually trigger metastasis, as cells are shed or the wound becomes inflamed. That may increase the chances that rogue cells will venture out and grow into a new tumor somewhere else, like the world's worst Whack-A-Mole game.
So the Vanderbilt team developed a way to seek and destroy these circulating cancer cells. The creation is called TNF-related apoptosis-inducing ligand (TRAIL), and is made up of two proteins attached to the surface of lipid nanoparticles, along with an adhesion receptor called E-selectin.
Once these nanoparticles are injected into the bloodstream, the E-selectin allows them to stick to white blood cells called leukocytes. These immune cells are already on the prowl for attackers like cancer, but the TRAIL coating makes them far more effective killers.
"Collisions between the TRAIL-coated leukocytes and cancer cells in the bloodstream are happening constantly," says Michael King, lead researcher on the study. "We've tested this both in the bloodstream and in hundreds of blood samples from cancer patients being treated in clinics across the country. In all cases, within two hours, the viable cancer cells are cleared out. This has worked with breast, prostate, ovarian, colorectal and lung cancer cells."
The researchers say this technique has had promising results in previous tests, but in this case, they managed to hone the treatment into three doses. The idea is that during surgery to remove a primary tumor, this treatment can be administered into the bloodstream to catch the escaping cells and prevent them from metastasizing later on. The team also suggests that it could be given to patients with cancer that's already spread to different sites.
While most of these tests so far have been conducted on mice, the team says that the transition to human trials should be relatively quick. That's because all the components of the treatment – the proteins, nanoparticles, and leukocytes – already occur naturally in the human body.
This technique is just the latest in a long line of research into preventing cancer from spreading. Other recent developments include identifying certain proteins involved in the process and either boosting or inhibiting their levels, molecules that could silence the spread or even blasting rogue cells with lasers.
The research was published in the journal Science Advances. The team describes the work in the video below.
Source: Vanderbilt University
