Cancers (Jul 2020)

CN133, a Novel Brain-Penetrating Histone Deacetylase Inhibitor, Hampers Tumor Growth in Patient-Derived Pediatric Posterior Fossa Ependymoma Models

  • Roberta Antonelli,
  • Carlos Jiménez,
  • Misha Riley,
  • Tiziana Servidei,
  • Riccardo Riccardi,
  • Aroa Soriano,
  • Josep Roma,
  • Elena Martínez-Saez,
  • Maurizio Martini,
  • Antonio Ruggiero,
  • Lucas Moreno,
  • Josep Sánchez de Toledo,
  • Soledad Gallego,
  • Jordi Bové,
  • Jacob M. Hooker,
  • Miguel F. Segura

DOI
https://doi.org/10.3390/cancers12071922
Journal volume & issue
Vol. 12, no. 7
p. 1922

Abstract

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Pediatric ependymoma (EPN) is a highly aggressive tumor of the central nervous system that remains incurable in 40% of cases. In children, the majority of cases develop in the posterior fossa and can be classified into two distinct molecular entities: EPN posterior fossa A (PF-EPN-A) and EPN posterior fossa B (PF-EPN-B). Patients with PF-EPN-A have poor outcome and are in demand of new therapies. In general, PF-EPN-A tumors show a balanced chromosome copy number profile and have no recurrent somatic nucleotide variants. However, these tumors present abundant epigenetic deregulations, thereby suggesting that epigenetic therapies could provide new opportunities for PF-EPN-A patients. In vitro epigenetic drug screening of 11 compounds showed that histone deacetylase inhibitors (HDACi) had the highest anti-proliferative activity in two PF-EPN-A patient-derived cell lines. Further screening of 5 new brain-penetrating HDACi showed that CN133 induced apoptosis in vitro, reduced tumor growth in vivo and significantly extended the survival of mice with orthotopically-implanted EPN tumors by modulation of the unfolded protein response, PI3K/Akt/mTOR signaling, and apoptotic pathways among others. In summary, our results provide solid preclinical evidence for the use of CN133 as a new therapeutic agent against PF-EPN-A tumors.

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