Researchers at the Niels Bohr Institute, University of Copenhagen have made considerable inroads in the search for a treatment that attacks cancer cells on the cellular level. This new type of treatment would target and destroy cancer cells and leave healthy cells unharmed. It would provide a gentler alternative to the more invasive cancer treatments currently used.
Chemotherapy and radiation are the most common forms of cancer treatment today. Each of these treatments is effective at killing cancerous cells, but unfortunately harms and destroys healthy cells at the same time. This results in many side effects, some of which are debilitating. In addition, the efficacy of these treatments is limited in cases where cancer has spread from the primary tumor site to other parts of the body.
In response to these issues with current cancer treatments, the researchers at the Niels Bohr Institute have been working towards finding a treatment that specifically targets malignant cells. The scientists have attempted to deceive cancer cells into absorbing a cytotoxin that ultimately destroys them, while leaving healthy cells unaffected.
Physicist Murillo Longo Martins, a post-doc in X-Ray and Neutron Science at the Niels Bohr Institute, hypothesized that there must be a way to create a microscopic vehicle that could move through the bloodstream and carry the cytotoxin directly to the cancer cells. This vehicle would then incite the cell to allow the cytotoxin in, which would ultimately lead to the destruction of the cell by the cytotoxin.
Martins used tiny magnetic beads to act as the vehicle. After the beads were injected into the bloodstream, a magnet was placed at the site of the tumor. The tiny beads, attracted by the pull of the magnet, traveled towards the tumor.
Once the vehicle was created, the researchers moved on to creating the load that the vehicle would carry. They encased the cytotoxin surrounding the magnetic beads in a ring-shaped sac, essentially creating a cytotoxic parcel.
Now that they had the vehicle and the parcel, the next step was to figure out how to get the cell to accept the parcel. Every cell has a protective membrane that guards against harmful substances and allows helpful substances to enter through receptors, or doorways. Each of these helpful substances must have a key that fits a specific doorway in the cell membrane. The researchers needed to figure out a helpful substance that would provide the key to allow the vehicle and its cytotoxic load to enter the cancer cell.
“I thought, why do breast cancer, lung cancer and ovarian cancer so often spread to the bones? 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,” explained Martins in a news release from the Niels Bohr Institute. He ultimately decided to coat the cytotoxic parcel with calcium phosphate.
The researchers conducted experiments using breast, lung and colon cancer cells, as well as healthy cells. The results were just what Martins had imagined.
“We could see that the nanoparticles with the cytotoxin 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. The healthy cells, meanwhile, do not show any evidences of absorbing the packages with the cytotoxin. This suggests that the method can be used to send cytotoxin around the body with reduced toxicity and could therefore be potentially safer for healthy cells,” explains Heloisa Bordallo, Associate Professor in X-Ray and Neutron Science at the Niels Bohr Institute.
Findings from the study were published in the journal Scientific Reports.
News release, Niels Bohr Institute – University of Copenhagen