Abstact

Dual-specificity tyrosine-regulated kinase 1A (DYRK1A) is crucial for normal brain development, and its disruption is linked to various cancers. DYRK1A drives glioblastoma (GBM) progression via stabilization of epidermal growth factor receptor (EGFR). Here, we describe two benzothiazole-derived DYRK inhibitors, FC-2 and FC-3, obtained by structure-activity optimization of a natural product lead. Both compounds inhibited DYRK1A with nanomolar potency and displayed selectivity across a kinase panel. The co-crystal structure of FC-3 with DYRK1A revealed ATP-competitive binding, with interactions at the hinge region. The DYRK-specific phenylalanine gatekeeper residue contributed to target selectivity. Generation of inhibitor-resistant mutants confirmed DYRK1A as the primary cellular target. In GBM cell-based models, FC-2 and FC-3 impaired neurosphere self-renewal, cell invasion, and EGFR stability, phenocopying DYRK1A loss. FC-2 crossed the blood-brain barrier and suppressed tumor growth, prolonging survival in intracranial xenografts. These findings identify FC-2 and FC-3 as small-molecule nanomolar inhibitors of DYRK1A, with potential therapeutic utility in GBM.