Gliomas are a group of brain tumors where the most common type is also the most aggressive one. Chemotherapy and radiation have little effect on malignant gliomas, and patients survive only about a year after being diagnosed. But research at Lund University in Sweden provides hope that it may be possible in the future to develop stem cells from the brain into a new way to treat gliomas.
Neural stem cells have been shown to have the ability to recognize signals from tumor cells in the brain and migrate there. If stem cells are injected into a part of the brain in laboratory animals with a glioma in another part of their brain, the stem cells migrate over to the tumor area.
This has spawned the idea of having stem cells transport drugs or immune stimulants to the tumor. This was the principle the Lund scientists wanted to test. But as it turned out, no extra assistance was needed: the stem cells themselves had the ability to combat the tumor.
"We were truly amazed when we saw this effect! To be sure about the phenomenon, we ran several experiments with other stem cells, and it was confirmed that certain neural stem cells actually have an anti-tumor effect," says Karin Staflin. She is describing the findings in her dissertation, which she will soon defend.
It is as yet unknown just why this happens. One plausible reason is that both normal neural stem cells and glioma cells are immature, not fully mature cells. They are therefore more like each other than any other types of cells in the brain, which may enable them to ‘speak’ to each other and influence each other. The research team at Lund has also shown that stem cells can cure colon cancer in lab animals.
"Cells in aggressive malignant cancer forms are often characterized as being more immature than their environment. This may be what enables neural stem cells to affect intestinal cancer cells," says Karin Staflin.
Many years of research remain before the newly discovered principle is ready to be tested on humans. First, researchers need to learn to understand the mechanisms better and identify the factors in neural cells which make them so effective. The notion is still new, but it does provide a glimmer of hope for a cure for a thus far incurable disease.
The dissertation is titled Neural progenitor cells in malignancy and injury of the brain: A Trojan horse for gliomas?
