Cancer therapies are often harsh because eradicating malignant cells entails damaging healthy tissue as well. But three studies from the past year may present a road map for singling out the cancer cells alone.
In one, researchers working with mice at the Institute of Molecular and Cellular Biology in Singapore used antibodies to target proteins inside cancer cells—an impressive feat, since the antibodies were long considered too large to cross the cancer cell’s outer membrane. Mice treated with the antibodies developed fewer tumors and lived at least 20 percent longer than untreated ones, holding the promise that similar techniques might eventually target a suite of intracellular cancer proteins.
A second study, out of MIT, used principles of computer engineering to design a molecular logic circuit that senses six different biomarkers, seeking out a chemical pattern unique to one type of cancer. When it finds that pattern, the circuit triggers production of a killer protein that destroys cancer cells but not others.
A third team, from Johns Hopkins University, has created a molecular switch that activates chemotherapy drugs only within cancer cells. To create the switch, biomolecular engineer Marc Ostermeier and colleagues marshaled a protein found in high levels in cancer cells to activate a second protein that he built in the lab. The second protein, in turn, toggles the chemo drug to its active state.
Although human trials are years away for all three of these strategies, they could usher in the sort of seek-and-destroy therapy that will target cancer but leave the patient otherwise relatively unscathed.
