Tiny cancer-fighting ROBOTS injected into patients' bodies could find and destroy tumours
Tiny ‘nanorobots’ could soon be launched into patients’ bodies to seek and destroy tumours , new research suggests.
In experiments, the tiny machines – a thousand times smaller than the width of a human hair – were programmed to cut off the tumour’s blood supply.
They were successful in treating breast, melanoma, ovarian and lung cancer in mice.
The technique uses a process called ‘DNA origami’ in which a key blood clotting enzyme called thrombin is attached to a sheet of genetic material.
Thrombin can block tumour blood flow by clotting the blood within the vessels that feed it – causing a sort of mini-heart attack for the cancer killing the tissue.
Professor Hao Yan, of Arizona State University , said: “We have developed the first fully autonomous, DNA robotic system for a very precise drug design and targeted cancer therapy.
“Moreover, this technology is a strategy that can be used for many types of cancer, since all solid tumor-feeding blood vessels are essentially the same.”
In the study, human cancer cells were injected into a mouse to induce tumour growth, before nanorobots were deployed to come to the rescue.
Around four thrombin molecules were attached to a flat DNA scaffold, before the flat sheet folded into a circle to make a hollow tube.
The key to programming a nanorobot that only attacks a cancer cell was to include a special payload on its surface, called a DNA aptamer.
The DNA aptamer could specifically target a protein, called nucleolin, that is made in high amounts only on the surface of tumour cells – and not healthy ones.
Once bound, the nanorobot was programmed to deliver its drug cargo in the very heart of the tumour.
The nanorobots worked fast, congregating in large numbers to quickly surround the tumour just hours after injection.
Lead scientist Professor Yuliang Zhao, said: “The nanorobot proved to be safe and immunologically inert for use in normal mice and, also in Bama miniature pigs, showing no detectable changes in normal blood coagulation or cell morphology.”
Most importantly, there was no evidence of the nanorobots spreading into the brain where it could cause unwanted side effects, such as a stroke.
After attacking tumors, most of the nanorobots were cleared and degraded from the body after 24 hours.
While the system is yet to be tested in humans, the researchers are optimistic about its use in the future.
Professor Yan added: “I think we are much closer to real, practical medical applications of the technology.”