Study uncovers unexpected connection between gliomas, neurodegenerative diseases

A protein typically associated with neurodegenerative diseases like Alzheimer's might help scientists explore how gliomas, a type of cancerous brain tumor, become so aggressive.

The new study, in mouse models and human brain tumor tissues, was published in Science Translational Medicine and found a significant expression of the protein TAU in glioma cells, especially in those patients with better prognoses.

Patients with glioma are given a better prognosis when their tumor expresses a mutation in a gene called isocitrate dehydrogenase 1 (IDH1). In this international collaborative study led by the Instituto de Salud Carlos III-UFIEC in Madrid, Spain, those IDHI mutations stimulated the expression of TAU. Then, the presence of TAU acted as a brake for the formation of new blood vessels, which are necessary for the aggressive behavior of the tumors.

"We report that the levels of microtubule-associated protein TAU, which have been associated with neurodegenerative diseases, are epigenetically controlled by the balance between normal and mutant IDH1/2 in mouse and human gliomas," says co-author Maria G. Castro, Ph.D., a professor of neurosurgery and cell and developmental biology at Michigan Medicine. "In IDH1/2 mutant tumors, we found that expression levels of TAU decreased with tumor progression."

That means levels of TAU could be used as a biomarker for tumor progression in mutant IDH1/2 gliomas, Castro says.