Cancer cells engineered with CRISPR slay their own kin
Using gene editing, scientists have hoodwinked tumor cells into turning against their own kind. Cancer cells circulating in the bloodstream have something of a homing instinct, able to find and return to the tumor where they originated. To capitalize on that ability, researchers engineered these roving tumor cells to secrete a protein that triggers a death switch in resident tumor cells they encounter.
The cancer-fighting cancer cells also have a built-in suicide switch — so the weaponized cells self-destruct before they can start tumors of their own, the team reports in the July 11 Science Translational Medicine. The new study isn’t the first attempt to fight cancer with cancer. Previous research has used circulating tumor cells to deliver cancer-killing viruses to noncirculating tumor cells, for example.
But the new approach uses a gene-editing technology called CRISPR/Cas9 to manipulate the offensive-line cancer cells and give them more sophisticated properties, such as the ability to self-destruct once no longer needed. Cells on the moveWhen circulating tumor cells (green) that are engineered with CRISPR to kill other tumor cells are injected into a mouse, they migrate over time to established tumor cells (red), as seen in these fluorescence photomicrographs. When circulating tumor cells (green) that are engineered with CRISPR to kill other tumor cells are injected into a mouse, they migrate over time to established tumor cells (red), as seen in these fluorescence photomicrographs.
Getting the technique to work took several steps. First, researchers hunted for a protein that could trigger cell death in many types of cancer cells. The winning candidate, a protein called S-TRAIL, killed off a variety of cancer cells and wasn’t particularly toxic to healthy cells.