Oct. 18 (UPI) -- Scientists from Northwestern University are taking a radical approach by testing the potential for arsenic to treat a deadly form of brain cancer.
The study by researchers at Northwestern University Feinberg School of Medicine and the Translational Genomics Research Institute, or TGen, identified arsenic trioxide as a potential new treatment for glioblastoma multiforme, or GBM, the most common and deadliest type of brain cancer.
GBM is responsible for roughly 17,000 deaths in the United States a year and has an average survival rate of about 15 months.
Arsenic trioxide has been the standard of treatment to prevent acute promyelocytic leukemia, or APL, a rare subtype of blood cancer.
Researchers at Northwestern participated in a clinical trial to test whether adding arsenic trioxide to the standard treatment of temozolomide, or TMZ, and radiation would be effective for treating GBM. That Phase II clinical trial found arsenic trioxide did not improve overall survival, but a deeper examination of data from the study suggested it could be effective for some patients -- inspiring the new study, which found it works for specific subgroups of patients with GBM.
"Our findings show that, for some patients, arsenic trioxide could be a powerful therapy that could extend the lives of certain glioblastoma patients by as much as three to four times the median expectation," Dr. Harshil Dhruv, an assistant professor in TGen's Cancer and Cell Biology Division, said in a press release.
"We were then able to identify these particular patients as having the same genomic signatures as those we had tentatively identified in our computer and laboratory screenings of potential therapies."
The study, published Tuesday in Molecular Cancer Research, identified mesenchymal, or MES, and proneural, or PN, glioma subtypes with genomic signatures that vary according to specific underlying genes.
"Arsenic trioxide was found to be the most potent compound in non-MES GBM cells," Dr. Jonathan Bell, of Northwestern University, said. "We found that PN GBM patients responded better to ATO (arsenic trioxide) than any other subtypes as demonstrated by longer overall and progression-free survival."
The study also showed the advantages of using arsenic trioxide to treat GBM in that it is a small molecule able to penetrate the blood-brain barrier. Arsenic is also cost effective because it is abundant in nature, the researchers say.
"Rather than treat all patients, we want to design a prospective clinical trial that we can enrich for those patients whose genomic signatures indicate they would be the best candidates for success," Dhruv said. "This would be a biomarker-driven, precision-medicine clinical trial for glioblastoma -- a way to match the right drug to the right patient."