Repurposing drugs to eliminate cellular origins of brain tumors

(Press-News.org) Glioblastomas are aggressive brain tumors with a median survival time of less than 22 months despite standard therapy including surgery, irradiation, and chemotherapy. It has become clear in recent years that not all cells within the brain tumor have an equal potential to divide and drive tumor growth. As such, a fraction of tumor cells called brain tumor stem cells (BTSCs) are thought to be the primary origin of tumor re-growth after surgery in addition to being resistant to standard treatments including chemotherapy and irradiation. Therefore, targeting BTSCs may be a way to effectively treat glioblastomas. 

In an effort to rapidly identify new treatments effective against BTSCs, a team of researchers from the University of Ottawa, Canada, tested Edaravone, an FDA-approved drug, for its efficacy against BTSCs, knowing that Edaravone blocks cellular processes which are important for the growth and survival of BTSCs. Indeed, in cell cultures in the lab, Edaravone inhibited BTSC growth at low concentrations and caused cell death at higher concentrations, whereas normal brain stem cells were relatively unaffected. Encouragingly, brain tumor growth was delayed in mice receiving Edaravone and the treatment prolonged their survival. This effect was even more pronounced when Edaravone was combined with irradiation therapy. Since Edaravone has already received FDA clearance for other conditions, this drug could potentially be repurposed for treating glioblastoma in a shorter timeframe. However, additional pre-clinical and clinical studies will first have to confirm that Edaravone is a safe and effective drug against glioblastomas. This results were published today in Stem Cell Reports.

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