Researchers in the US have successfully conducted the first small-scale clinical trial to test a gene-editing treatment for cancer. They extracted t-cells, which are immune cells, from three cancer patients and edited their DNA with Crispr-Cas9, a powerful tool which works like molecular scissors to remove with great precision part of the cells’ genetic code and replaced it with new sections. These genetically engineered t-cells were then injected back into the patients. So far these cells have been able to attack tumours over a period of some months. Cancer cells multiply because they find ways to evade the immune system. Immunotherapy boosts the body’s natural defences and allows white blood cells to attack cancer cells.
This very small-scale trial shows that this particular technique of genetic engineering has been safe so far, but much more work is needed to make sure that it remains effective and is suitable for all cancer types.