Repurposing existing drugs for cancer stem cell-directed therapy

Abstract

Cancer stem cells (CSCs) pose a significant challenge in tumor treatment due to their ability to remain quiescent during therapy and thus evade chemo- and radio-therapy. In addition, their ability to initiate tumor formation from a single cell is another essential factor to consider when developing a strategy to eradicate CSCs. Given that developing novel drugs is a time-consuming and costly process, drug repurposing has become an increasingly utilized and appealing alternative in recent research. Drug repurposing involves testing existing medications that have already completed substantial portions of drug development for the treatment of new medical conditions. Artificial intelligence tools can assist in this process. This review presents a series of compounds, initially developed for a wide range of conditions, including antidiabetic, antipsychotic, anti-inflammatory, cholesterol-lowering, and antiparasitic drugs, that can be repurposed as targeted therapies for CSCs. Metformin and doxycycline have also been evaluated in clinical studies targeting CSCs. Furthermore, novel artificial intelligence tools will be vital for predicting the potential of repurposed drugs before in vitro and in vivo testing.

Keywords

Cancer stem cells / Therapy / Chemoresistance / Radioresistance / Drug repurposing

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