The active ingredient in a traditional Chinese herbal remedy might help treat deadly brain tumors, according to a new study by researchers at the Ohio State University Comprehensive Cancer Center -- Arthur G. James Cancer Hospital and Richard J. Solove Research Institute (OSUCCC -- James). The researchers discovered that the compound, indirubin, both blocks the migration of glioblastoma cells, preventing their spread to other areas of the brain, and the migration of endothelial cells, preventing them from forming the new blood vessels that the tumor needs to grow.