Therapeutic use of gene editing with the so-called CRISPR-Cas9 technique may inadvertently increase the risk of cancer, according to a new study from Karolinska Institutet, Sweden, and the University of Helsinki, Finland, published in Nature Medicine.
Researchers say that more studies are required in order to guarantee the safety of these ‘molecular scissors’ for gene-editing therapies.
CRISPR-Cas9 is a molecular machine first discovered in bacteria that can be programmed to go to an exact place in the genome, where it cuts the DNA. These precise ‘molecular scissors’ can be used to correct faulty pieces of DNA and are currently being used in clinical trials for cancer immunotherapy in the US and China. New trials are expected to be launched soon so as to treat inherited blood disorders such as sickle cell anaemia.
Two independent articles published in the journal Nature Medicine now report that therapeutic application of the genome-editing tool may, in fact, increase the risk of cancer. In one of the studies, scientists from Karolinska Institutet and the University of Helsinki report that use of CRISPR-Cas9 in human cells in a laboratory setting can activate a protein known as p53, which acts as a cell’s ‘first aid kit’ for DNA breaks. Once active, p53 reduces the efficiency of CRISPR-Cas9 gene editing. Thus, cells that do not have p53 or are unable to activate it show better gene editing. Unfortunately, however, lack of p53 is also known to contribute to making cells grow uncontrollably and become cancerous.