Researchers at The Institute of Cancer Research and Cancer Research UK have successfully produced a gene therapy that may one day serve as a treatment for advanced bowel cancer that doesn’t respond to standard chemotherapy. The treatment is known as GDEPT—Gene-Directed Enzyme Prodrug Therapy.
The therapy uses a virus to attack cancer cells. An extra gene is added to the virus. The virus is programmed to switch on the gene only if it reaches a tumor. Once switched on, the virus will then produce a protein that activates an otherwise harmless prodrug, given separately.
The cancer cells “commit suicide” both by the virus and the activated drug. The DNA inside the cancer cells is damaged to the point where the cells stop functioning. They have no choice but to shut down and die. In normal tissue, the drug remains inactive, so healthy cells are not affected.
In animal trials, mice with bowel tumors that received the therapy lived twice as long as those that did not receive the therapy. Clinical trials are expected in the future.
Illustration: MicroSoft clipart.