Leukemia and lymphoma drug may benefit patients with deadliest brain tumor

Ibrutinib, an FDA-approved drug for treatment of leukemia and lymphoma may also help in the treatment of glioblastoma (GBM), most common and deadliest type of brain tumor, suggests a study published in the journal Science Translational Medicine. The findings instill a hope of improved survival in glioblastoma patients.

The study was conducted by Shideng Bao, a researcher at Cleveland Clinic's Lerner Research Institute and colleagues, who found that ibrutinib slowed brain tumor growth in a preclinical model and extended survival more than 10-times the rate of the current standard-of-care chemotherapy drug.

Ibrutinib (Imbruvica) has been approved by the U.S. Food & Drug Administration to treat certain types of leukemia and lymphoma, as well as chronic graft versus host disease.

Glioblastoma is the most lethal primary brain tumor and is highly resistant to current treatments. BM harbors glioma stem cells (GSCs) that not only initiate and maintain malignant growth but also promote therapeutic resistance including radioresistance. Targeting GSCs is thus, critical for overcoming the resistance to improve GBM treatment.

The median survival of glioblastoma patients undergoing standard treatment is less than 15 months, according to American Brain Tumor Association.

The researchers found that ibrutinib works by inhibiting glioma stem cells – an aggressive type of brain cancer cell that tends to resist treatment and spread. Furthermore, they showed that combining ibrutinib with radiation therapy prevents glioblastoma cells from developing this resistance. Combination therapy overcame resistance and extended lifespan more effectively than either radiation or ibrutinib treatment alone.

"Glioblastoma is the most lethal primary brain tumor and is highly resistant to current therapies," said Bao. "There is an urgent need to get new treatments to these patients as quickly as possible."

In earlier studies, Bao and colleagues found that glioma stem cells have high levels of a protein called BMX (bone marrow and X-linked non-receptor tyrosine kinase). BMX activates a protein called STAT3 (signal transducer and activator of transcription 3), which is responsible for the aggressive, pro-cancer qualities of glioma stem cells. In this new study, the researchers found that ibrutinib works by inhibiting both proteins.

"Additional research is important to understand the effects of ibrutinib in patients, but these early findings are promising," said Bao. "Using an FDA-approved drug would allow us to surpass many of the lengthy regulatory studies needed when developing a new treatment, and we could potentially begin clinical trials very soon."

For further information click on the link: 10.1126/scitranslmed.aah6816