Cancer treatments, like chemotherapy and radiation, are notorious for their nasty side effects and the damage they do to healthy cells surrounding the cancerous ones. Researchers are constantly exploring new possible treatments, and a team from the Niels Bohr Institute has developed a different approach to taking out cancer that involves tricking and poisoning cancer cells, leaving healthy cells unaffected.

Physicist Murillo Martins of the University of Copenhagen aimed to construct a nanoscale vehicle capable of transporting a toxin to cancer cells, which would then absorb and destroy it. The researcher and his team had a twofold task: create both the vehicle and the toxic load capable of taking down cancer cells. Martins decided on tiny magnetic beads for the vehicle, an approach well known in medical research. The beads can be injected into the bloodstream, and by placing a magnet at the site of the tumor, researchers can get the beads to move there. Figuring out the toxin was next, and researchers were eventually able to couple it with a ring-shaped sac around the beads. Once the toxin was where it needed to be, the problem shifted to getting the package into a cancer cell.

Cells have surrounding membranes responsible for warding off foreign substances and protecting the cell. However, cell membranes have receptors that, if activated, can allow a substance to enter. Like a key to a lock, the substance must have the right activation on the receptor to be allowed into the cell. based on the spread of certain cancers, Martins created a coating of calcium phosphate for the toxin package.

“I thought, why do breast cancer, lung cancer, and ovarian cancer so often spread to the bones?” Martin said. “Bones are composed of minerals like calcium phosphates. Do cancer cells need these substances to grow? Can these substances be used as doorways to the cell? I decided to investigate this.”

The researchers did experiments with breast, lung, and colon cancer cells, along with healthy ones, to see if the package could really fool its way into a cancer cell. They found that cancer cells and healthy cells responded to the packages quite differently.

“We could see that the nanoparticles with the toxin were absorbed by the cancer cells. This caused the metabolism of the cancer cells to change and the cells showed signs that they were about to die,” said Heloisa Bordallo, associate professor in X-ray and neutron science at the Niels Bohr Institute. “The healthy signs, meanwhile, do not show any evidences of absorbing the packages with the toxin. This suggests that the method can be used to send toxin around the body with reduced toxicity and could therefore be potentially safer for healthy cells.”

Source: Martins M, Ignazzi R, Eckert J, Watts B, Kaneno R, Zambuzzi W, et al. Restricted mobility of specific functional groups reduces anti-cancer drug activity in healthy cells. Scientific Reports. 2016.