Last year, I wrote about a team of Chinese scientists having received ethical approval to perform a clinical trial of gene-editing. The goal was to test whether gene-editing may be a potential cure for cancer. The technology used for the trial is called CRISPR/Cas9, not exactly a household name. CRISPR stands for Clustered Regularly Interspaced Short Palindromic Repeats. Cas9 stands for CRISPR associated protein 9, an RNA-guided DNA endonuclease enzyme. If you read all these words a few times, it can make your head hurt. The topic is complex, but I hope in this post to make it more understandable.
After reading about CRISPR more than a few times, I think I finally get the concept. I may not have this 100% right, but following is what I believe it is about. To imagine what gene-editing is, consider editing of a video. The software shows you each frame of the video. You select a frame you want to edit and display the frame in video editing software. You make the changes to look the way you want the frame to look, and then insert the frame back into the video. For example, the original video may have contained an unneeded “um” or “ah” or “eh” which added no value to the video.
Now, consider the similarity with gene-editing. The human body has T-cells which are an active participant in our immune system. A gene in the T-cells can produce a protein called PD-1 which disables the T-cells’ ability to trigger an immune response to fight cancer. A team of oncologists removed cells from an advanced stage lung cancer patient and edited the cells using CRISPR-Cas9. After editing out the gene which blocks the immune response, the cells were cultured and multiplied and then injected back into the patient.
Traditional treatments are aimed at killing the cancer cells. Sometimes it works, and sometimes it does not. The gene editing approach is designed to modify our DNA and have our body fight the cancer instead of chemotherapy. Some top experts are very optimistic CRISPR/Cas9 may become the cure researchers have been seeking for decades.
Gene-editing is a breakthrough technology which could change how oncologists treat cancer. Laboratory experiments have shown it is possible to literally eliminate tumors. There are at least several significant risks, and many trials will be needed to test the safety and efficacy of gene-editing.
Carl June, an immunotherapy specialist at the University of Pennsylvania in Philadelphia is a U.S. leader in the hunt for new cancer cures. He said, “I think this is going to trigger “Sputnik 2.0″, a biomedical duel between China and the United States”. He further said this is important since competition usually improves the end product. As of now, it looks like the Chinese are ahead in the race. That may be about to change.
The National Institutes of Health (NIH), this week, announced a major effort aimed at removing barriers which slow the adoption of genome editing for treating patients. The program, called Somatic Cell Genome Editing, will be investing $190 million over six years, beginning this year. The financial grants will go to researchers to collaborate to improve the delivery mechanisms for gene editing tools for patients, develop new and improved genome editors, and to develop methods for testing the safety and efficacy of the genome editing tools. The goal is to create a genome editing toolkit built from what is learned from the research, and share it with the entire scientific community.
“Genome editing technologies such as CRISPR/Cas9 are revolutionizing biomedical research,” said NIH Director Francis S. Collins, M.D., Ph.D. “The focus of the Somatic Cell Genome Editing program is to dramatically accelerate the translation of these technologies to the clinic for treatment of as many genetic diseases as possible.”
I will continue to follow this important and exciting area of medical research.
