According to the MGH Public Affairs website:
"The researchers first pretreated immune-deficient mice by delivering a gene for human interferon-beta – a protein being tested against several types of cancer – into the animals’ brains using adeno-associated virus vectors known to effectively deliver genes to neurons in the brain without the immune reaction produced by other vectors. Two weeks later, human glioblastoma cells were injected into the same or adjacent areas of the animal’s brains. After only four days, mice expressing interferon-beta had significantly smaller tumors than did a control group pretreated with gene-free vector. Two weeks after the glioblastoma cells were introduced, the tumors had completely disappeared from the brains of the gene-therapy-treated mice."
There are still many questions to be answered and many more studies to be done.
"Since interferon-beta treatment is known to have side effects, it will be important to identify any toxicity caused by long term secretion of the protein in the brain and develop preventive strategies, such as turning off the introduced genes. Next the MGH team is planning to test this strategy on glioblastomas that occur naturally in dogs, which could not only generate additional data supporting human trials but also develop veterinary treatments for canine patients."
I'll be watching this study closely, hoping it is successful.