Development of Chromosome 1q+ Specific Treatment for Highest Risk Pediatric Posterior Fossa Ependymoma

Clin Cancer Res. 2024 Apr 15;30(8):1544-1554. doi: 10.1158/1078-0432.CCR-23-3156.


Purpose: There are no effective treatment strategies for children with highest-risk posterior fossa group A ependymoma (PFA). Chromosome 1q gains (1q+) are present in approximately 25% of newly diagnosed PFA tumors, and this number doubles at recurrence. Seventy percent of children with chromosome 1q+ PFA will die because of the tumor, highlighting the urgent need to develop new therapeutic strategies for this population.

Experimental design: In this study, we utilize 1q+ PFA in vitro and in vivo models to test the efficacy of combination radiation and chemotherapy in a preclinical setting.

Results: 5-fluorouracil (5FU) enhances radiotherapy in 1q+ PFA cell lines. Specifically, 5FU increases p53 activity mediated by the extra copy of UCK2 located on chromosome 1q in 1q+ PFA. Experimental downregulation of UCK2 resulted in decreased 5FU sensitivity in 1q+ PFA cells. In in vitro studies, a combination of 5FU, retinoid tretinoin (ATRA), and radiation provided the greatest reduction in cellular proliferation and greatest increase in markers of apoptosis in 1q+ PFA cell lines compared with other treatment arms. Similarly, in vivo experiments demonstrated significant enhancement of survival in mice treated with combination radiation and 5FU and ATRA.

Conclusions: These results are the first to identify a chromosome 1q+ specific therapy approach in 1q+ PFA. Existing phase I studies have already established single-agent pediatric safety and dosages of 5FU and ATRA, allowing for expedited clinical application as phase II trials for children with high-risk PFA.

MeSH terms

  • Animals
  • Child
  • Chromosomes / metabolism
  • Ependymoma* / genetics
  • Ependymoma* / therapy
  • Fluorouracil
  • Humans
  • Infratentorial Neoplasms* / genetics
  • Infratentorial Neoplasms* / pathology
  • Infratentorial Neoplasms* / therapy
  • Mice
  • Treatment Outcome


  • Fluorouracil