Abstract For decades, the survival rate for glioblastoma (GBM) has remained nearly stagnant, with a 5-year survival rate of only 5%. There is an unmet medical need for therapeutic development, because while GBM is the most common primary brain tumor, only four FDA approved drugs have been developed for GBM over the last century. By taking advantage of RNA sequencing, a potential target for GBM has been identified: the kinase STK17A (Serine/Threonine Kinase17A). We confirmed that STK17A is overexpressed in gliomas by analyzing public databases and single-cell RNA sequencing from our own GBM patients, and further associated it with poor patient outcome. Little is known about STK17A, but it has been found to be involved in cell proliferation and tumorigenesis. The role of STK17A in GBM pathophysiology and its therapeutic potential as a drug target remains a critical knowledge gap. To better understand STK17A’s role in GBM pathophysiology, we first knocked down STK17A in GBM cell lines and determined that STK17A had functional roles in proliferation and morphology. Similar conclusions were drawn after removing STK17A in GBM xenograft mouse models. These findings support STK17A as a viable therapeutic target. We then designed and optimized novel STK17A inhibitors for evaluations through kinase enzymatic and biological assays, in vitro proliferation and toxicity assays, and in vivo Drug Metabolism and Pharmacokinetics (DMPK) assays. We then used these potent, selective, and highly brain penetrant STK17A inhibitors to investigate the anti-tumor effects of STK17A inhibition in GBM and demonstrate the efficacy of our novel STK17A inhibitors in vivo. In conclusion, this work seeks to contribute to the field of targeted therapies for GBM by optimizing and examining a novel brain penetrant STK17A inhibitor, initiating studies for the treatment of GBM in vitro and in vivo, and providing proof of efficacy for further studies in GBM patients.
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