Superenhancer activation of KLHDC8A drives glioma ciliation and hedgehog signaling

J Clin Invest. 2023 Jan 17;133(2):e163592. doi: 10.1172/JCI163592.

Abstract

Glioblastoma ranks among the most aggressive and lethal of all human cancers. Self-renewing, highly tumorigenic glioblastoma stem cells (GSCs) contribute to therapeutic resistance and maintain cellular heterogeneity. Here, we interrogated superenhancer landscapes of primary glioblastoma specimens and patient-derived GSCs, revealing a kelch domain-containing gene, specifically Kelch domain containing 8A (KLHDC8A) with a previously unknown function as an epigenetically driven oncogene. Targeting KLHDC8A decreased GSC proliferation and self-renewal, induced apoptosis, and impaired in vivo tumor growth. Transcription factor control circuitry analyses revealed that the master transcriptional regulator SOX2 stimulated KLHDC8A expression. Mechanistically, KLHDC8A bound chaperonin-containing TCP1 (CCT) to promote the assembly of primary cilia to activate hedgehog signaling. KLHDC8A expression correlated with Aurora B/C Kinase inhibitor activity, which induced primary cilia and hedgehog signaling. Combinatorial targeting of Aurora B/C kinase and hedgehog displayed augmented benefit against GSC proliferation. Collectively, superenhancer-based discovery revealed KLHDC8A as what we believe to be a novel molecular target of cancer stem cells that promotes ciliogenesis to activate the hedgehog pathway, offering insights into therapeutic vulnerabilities for glioblastoma treatment.

Keywords: Cancer; Oncology; Stem cells.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Brain Neoplasms* / pathology
  • Cell Line, Tumor
  • Cell Proliferation
  • Glioblastoma* / pathology
  • Glioma* / metabolism
  • Hedgehog Proteins / genetics
  • Hedgehog Proteins / metabolism
  • Humans
  • Neoplastic Stem Cells / pathology
  • Signal Transduction

Substances

  • Hedgehog Proteins
  • KLHDC8A protein, human