|Lung cancer invades a healthy cell.|
The Chinese team, lead by oncologist Lu You at Sichuan University in Chengdu, used CRISPR/Cas9 to treat a patient with non-small-cell lung cancer as a part of a clinical trial. This could be the first step toward completely new cancer therapies.
Heralded as one of the biggest biotechnology breakthroughs of the century, the CRISPR/Cas9 technique allows scientists to repair broken genes more easily and more efficiently than previous methods. It starts with an RNA molecule that matches the DNA sequence of a targeted gene. The RNA works like a guide, bringing the enzyme Cas9 to the damaged bit of DNA, where it's used to snip out the damage, replace it or repair it.
The technique, first reported in Science in 2012 by Jennifer Doudna at the University of California, Berkeley, and Emmanuelle Charpentier, now at the Max Planck Institute for Infection Biology in Berlin, lets a researcher change any part of the DNA of any organism. It has the potential to cure diseases, engineer crops to withstand extreme environments and even eradicate pathogens.
After the Science paper was published, several scientists began experimenting with the technique. But then in 2015, scientists in Beijing used CRISPR to modify genes in a human embryo. The embryo was not allowed to develop into a human, but the implications were obvious. CRISPR could be used to modify human beings before they were born.
Shortly thereafter, the National Institutes of Health established the Recombinant DNA Advisory Committee to review and make recommendations on any research studies that involved using techniques like CRISPR on humans.
Although many scientists felt that taking a more conservative approach was important, it slowed progress. Meanwhile, researchers in China forged on.
In this latest advance, Dr. Lu and his team removed immune cells from a patient's blood. They used the CRISPR/Cas9 technique to disable a gene responsible for producing a protein, PD-1, that stops a cell from having an immune response. Cancer cells use the lack of an immune response to their advantage in order to grow and spread.
Lu and his team cultured cells with the modified genes in order to grow more and then injected them into the patient. The hope is that without the ability to produce a protein that stops an immune response, the cells could launch an effective attack against the cancer.
This is the first time that genes edited with the CRISPR/Cas9 technique have been injected into a human. Researchers in the United States want to be next.
"I think this is going to trigger 'Sputnik 2.0', a biomedical duel on progress between China and the United States, which is important since competition usually improves the end product," Carl June, who specializes in immunotherapy at the University of Pennsylvania in Philadelphia and led one of the earlier studies, told Nature.
At the moment, the only clinical study in the United States to get the green light from the Recombinant DNA Advisory Committee is one built around research developed in June's lab at UPenn. June and his colleagues used CRISPR/Cas-9 to genetically modify immune cells, known as T cells, to treat leukemia and other cancers.
Read more at Discovery News