Pharmacological blockade of high-risk MYCN driven neuroblastoma using an orally-bioavailable CDK2/9 inhibitor

The undruggable nature of oncogenic Myc transcription factors poses a therapeutic challenge in neuroblastoma, a paediatric cancer in which MYCN amplification is strongly associated with unfavourable outcome. Here, we show that CYC065, a clinical inhibitor of CDK2 and CDK9, selectively targets MYCN-amplified neuroblastoma via blockade of CDK9-dependent, MYCN-driven transcriptional elongation and CDK2-dependent proliferation. CYC065 also targets nascent transcription of short half-life genes including MYCN and MCL-1 leading to downregulation of MYCN-driven ‘adrenergic’ gene expression programs, growth inhibition, and apoptosis in vitro and in vivo. These data highlight the clinical potential of CDK2/9 inhibition in the treatment of MYCN-amplified neuroblastoma. ChIP-seq in SHEP and SHEP MYCN neuroblastoma cell lines for H3K27ac, MYCN