Gold is precious in more ways than one. In the fight against cancer, gold nanoparticles allowed scientists to trace the path of radiation through the body. Using this information, the researchers then tagged the gold nanoparticles with drugs that hit cancer right where it counts. The effect was a one-two punch to cancer cells.
Scientists have devised numerous ways to kill cancer. However, a long-standing obstacle has been effectively targeting the drugs to the cancer cells and not the healthy cells. In fact, some studies show that only a very small percent of anticancer drugs actually makes it to the desired tumor location. Thus, in many cases, cancer treatments become a delicate balancing act for both doctors and patients.
To know precisely where anticancer drugs end up, scientists at the Oxford Institute for Radiation Oncology outfitted drugs with gold nanoparticles laced with minute quantities of a radioactive tracer. This allowed the team to track the path of the drugs to inside the nucleus of cells, where the telomeres are located.
Telomeres are like protective caps at the ends of chromosomes. But these structures get shorter and shorter with each successive replication cycle. When it becomes too short, the cell dies. In effect, proper telomeres prevent cells from living immortal lives. In the case of some cancers, more telomerase enzymes are made, which bypasses telomere shortening and allows cancer cells grow and divide endlessly.
Knowing this, the team targeted the gold nanoparticles to a telomerase-positive cancer. They followed the exact path of the drug and showed the direct hit on telomerases, which more effectively killed the cancer cells because they become more sensitive to radiation.
“We have used tiny gold nanoparticles loaded with targeted drugs to kill cancer cells in the laboratory. Our long term goal is to design new treatments for cancer patients based on this promising approach," said Kate Vallis, the study’s lead author.
"Gold has been used in medicine for many years and this research adds further insight into its potential. Ensuring that treatment is accurately targeted at cancer and avoids healthy cells is the goal for much of cancer research, and this is an exciting step towards that,” said Harpal Kumar, Cancer Research UK's chief executive.
"Research continues to shed light on how cancer cells behave and how to effectively deliver a lethal payload to the tumour. This exciting research offers that potential and needs further investigation to see how it would be used in patients. The future looks exciting with research such as this improving the way the disease is treated,” said Karen Kennedy, Director of the NCRI.
Additional sources: Cancer Research UK, Azo Nano