In a first-of-its-kind experiment, scientists have discovered that cells found in bone marrow could dramatically improve the chances of beating or at least slowing a particularly aggressive and malignant brain cancer.
A New Lifeline: Targeting Glioma with miRNA
Researchers from Henry Ford Hospital, a Detroit, MI, hospital responsible for some of the leading research into fighting brain cancers, decided to concentrate their efforts on the most common type of aggressive brain tumor, and often the one most likely to lead to fatality, the glioma.
The researchers injected glioma cells into the brains of anesthetized male lab rats and then allowed those cells to grow for a period of five days.
In that time, researchers prepared mesenchymal bone marrow cells (MSCs), not for the cells themselves but rather for what they secrete: exosomes.
Once thought solely to carry out a blunt but rather necessary function of dealing with aged plasma membrane proteins that are no longer needed by the body, researchers have deduced that exosomes may be far more useful because they contain miRNA. These molecules are of special importance for medical treatments because they can be engineered for specific functions, and in this case, to attack or treat specific ailments.
The researchers at Henry Ford engineered exosomes containing miR-146b, which is already known to have a strong effect on glioma cells. They then injected the molecules directly into the rat subjects’ developing tumors.
A Promising Outcome for Glioma Treatment
Five days later, the rats were euthanized and their brains removed for study.
The researchers found that just one injection containing miR-146b five days after implantation of the tumor led to a significant reduction in the tumor’s volume 10 days after implantation.
Henry Ford researchers suggest that miR-146b actually creates what they have termed an “anti-tumor effect” in the rat brain.
If this benefit were to translate to human patients, the import would be significant, because while this does not necessarily mean a cure, it would allow for a significantly larger window of treatment.
Among the High Grade Gliomas (HGG), Glioblastoma Multiforme (GBM) is one of the most malignant and aggressive forms of brain tumor in humans.
It is estimated that around 12,000 people are diagnosed with GBM every year in the U.S.
Half of those will die within a year and the rest within three years. This is because, despite our best efforts, current treatments are largely ineffective and in fact the need for aggressive treatment often leaves the patient with a low quality of life.
For this reason, this research could be highly significant.
“This is the first foray of its type in experimental cancer therapy, and it represents a highly novel and potentially effective treatment,” Michael Chopp, Ph.D., scientific director of the Henry Ford Neuroscience Institute, is quoted as saying in a press release.
“I think this is an important and very novel approach for the treatment of cancers, and in this particular case the treatment of glioma,” Dr. Chopp added. “We have been at the forefront of developing microRNAs as a means to treat disease, such as cancer and neurological injury.”
The research is published in the current issue Cancer Letters, and can be found online here.
Leading Research, But At What Cost?
The big caveat to this research is that the experiment involved rat test subjects and so there is a great deal still to do and prove before this research could be viable for human treatment.
There are obviously a number of ethical issues raised by this study and they cannot be ignored.
While animal research is now largely heavily controlled and has been restrained by staunch and far reaching protocols to purportedly minimize subjects’ suffering, it is an inescapable fact that a number of test rats in this case were forcibly injected with cancerous cells, then further injected with the microRNAs, and then killed so that their brains could be studied.
For many who believe that animal testing is fundamentally wrong, no matter the important breakthrough this could mean for glioma patients, the techniques used here will do little to dissuade that such tests can be justified.
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