CRISPR-Cas9 is a gene editing technique that is faster, cheaper and more accurate than previous methods. With CRISPR-Cas9, geneticists and medical researchers can remove, add, or alter sections of the DNA sequence. Until now, the technique has not been used in conjunction with human medical treatment. China has changed that.
The technique uses two main molecules, an enzyme named Cas9 and a piece of RNA referred to as RNA (gRNA), to change or cause mutation in DNA. Cas9 is the pair of “genetic scissors” that cut strands of DNA at specific locations in the genome and RNA (gRNA) serves as guides for the genome to follow in altering the sequence. In lung cancer treatment, this method targets the cells that aid the proliferation of cancerous cells.
“Despite safety fears and scalability questions, success in this treatment could deal a huge blow to lung cancer.”
China First to use CRISPR-Cas9 on Human Subject
Using CRISPR-Cas9, oncologist Lu You from Sichuan University in Chengdu and collaborators edited cell DNA and then injected the altered cells into a lung cancer patient.
Lu You and his team first extracted immune cells from the patient’s blood. Next, they targeted a disabled a gene that provides code for the growth of the protein PD-1 using CRISPR. The disabled gene stops a cell’s immune response, and cancer takes advantage of that to spur growth. In the final step, the team injected a large number of cells back into a human patient with aggressive lung cancer. The expectation is that the edited cells will attack cancerous cells and promote an immune response.
The patient involved in the study is slated for additional injections. Ten other hopeful lung cancer patients will receive injections during this trial phase.
Jockeying for Position, the U.S. is not far Behind
According to Carl June, immunotherapy specialist at the University of Pennsylvania in Philadelphia, the Chinese team’s actions will lead to what he calls “Sputnik 2.0.” That is, the U.S. and other nations will see themselves as falling behind in the race to make practical gene editing in humans.
Meanwhile, the U.S. trial of CRISPR-Cas9 is planned for 2017, almost a full year behind the Chinese trial at Sichuan University. More Chinese CRISPR treatments are expected in 2017.
Promising Results in Lung Cancer Treatment
Although You’s team has not provided details of the lung cancer patient’s response after injection of the edited cells, reports suggest there have been no negative side-effects. The team claims the patient is likely to recover.
While signs are promising, some experts raise questions about its viability. According to Naiyer Rizvi of the Columbia University Medical Center, the treatment process is “a huge undertaking and not very scalable.”
Despite safety fears and scalability questions, success could mark huge strides in lung cancer treatment. If Carl June is right, a technological race between the U.S. and China might make curing cancer a reality.