A team of Harvard Medical School scientists has engineered cells that can destroy cancer, marking another breakthrough in the red-hot realm of stem cell research. Their experiments on mice have proved that these cells secrete toxins that effectively target and kill brain tumours. Tests on humans will follow as a precursor to FDA approval. The method was developed by the scientists to destroy residual tumour cells– that is cancer cells that remain in the brain after a main tumour has been removed surgically.
Planted around the cancer site in a biodegradable gel, the toxins secreted by these cells infiltrate the cancer cells and disrupt their ability to make proteins leading to their death. In earlier such attempts the toxins tended to not only affect the tumours but also healthy cells around them.
“Cancer-killing toxins have been used with great success in a variety of blood cancers, but they don’t work as well in solid tumors because the cancers aren’t as accessible and the toxins have a short half-life,” team lead Khalid Shah said. “A few years ago we recognized that stem cells could be used to continuously deliver these therapeutic toxins to tumors in the brain, but first we needed to genetically engineer stem cells that could resist being killed themselves by the toxins.”
Chris Mason, professor of regenerative medicine at University College London, said, “It shows you can attack solid tumors by putting mini pharmacies inside the patient, which deliver the toxic payload direct to the tumor.”