In the paper, published in February, an international team of scientists demonstrated the effectiveness of using DNA nanorobots to attack tumors in mice and pigs with cancer. These nanometer-sized robots are made of DNA that unfolds itself at precisely the right time and place to deliver a drug to only the exact target in the body. The DNA, folded up like an origami package, held molecules of thrombin, an enzyme that makes blood clot.
DNA origami nanorobot
When this DNA origami nanorobot detects blood vessels associated with tumors, it opens up to deliver thrombin, a clotting factor that chokes off the blood supply to the tumor.
To test whether this novel drug delivery system works, the team of scientists from Arizona State University and the National Center for Nanoscience and Technology of the Chinese Academy of Sciences injected the nanorobots into the bloodstreams of mice with tumors. They found that the treatment effectively targeted tumors, stopping their growth and even initiating tumor death.
One of the problems with fighting cancer cells comes from the inability of drugs to distinguish between the cells that make up a tumor and the body’s own healthy ones. To get around this, the researchers decided not to kill off the cells themselves but the vessels supplying them with blood. And they did this using nanobots.
“We have developed the first fully autonomous, DNA robotic system for a very precise drug design and targeted cancer therapy,” says Hao Yan, co-author of the study published in Nature Biotechnology, in a statement. “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.”
The team took a rectangular piece of DNA origami sheet – measuring just 90 nanometers by 60 nanometers – and peppered it with a protein known as thrombin. This is a naturally occurring enzyme found in the body that induces clotting. The aim here is to deliver the protein to the blood vessels that supply the tumor with its nutrients and cut them off, effectively starving the cancerous cells.
Dr Hao Yan of Arizona State University said in a press release: “We have developed the first fully autonomous DNA robotic system for a very precise drug design and targeted cancer therapy”.
Translation: These little biological weapons were able to deliver a dose of lifeblood-blocking, clot-inducing medicine to mice with human breast cancer tumors. The results included stunted tumor growth, shrinkage of existing tumors and metastasis, and inhibition of metastases. In the melanoma mouse model, 3 in 8 mice had complete tumor regression.
h/t Digital mix guy