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Acta Neuropathologica

, Volume 134, Issue 5, pp 705–714 | Cite as

Immunohistochemical analysis of H3K27me3 demonstrates global reduction in group-A childhood posterior fossa ependymoma and is a powerful predictor of outcome

  • Pooja Panwalkar
  • Jonathan Clark
  • Vijay Ramaswamy
  • Debra Hawes
  • Fusheng Yang
  • Christopher Dunham
  • Stephen Yip
  • Juliette Hukin
  • Yilun Sun
  • Matthew J. Schipper
  • Lukas Chavez
  • Ashley Margol
  • Melike Pekmezci
  • Chan Chung
  • Adam Banda
  • Jill M. Bayliss
  • Sarah J. Curry
  • Mariarita Santi
  • Fausto J. Rodriguez
  • Matija Snuderl
  • Matthias A. Karajannis
  • Amanda M. Saratsis
  • Craig M. Horbinski
  • Anne-Sophie Carret
  • Beverly Wilson
  • Donna Johnston
  • Lucie Lafay-Cousin
  • Shayna Zelcer
  • David Eisenstat
  • Marianna Silva
  • Katrin Scheinemann
  • Nada Jabado
  • P. Daniel McNeely
  • Marcel Kool
  • Stefan M. Pfister
  • Michael D. Taylor
  • Cynthia Hawkins
  • Andrey Korshunov
  • Alexander R. Judkins
  • Sriram Venneti
Original Paper

Abstract

Posterior fossa ependymomas (EPN_PF) in children comprise two morphologically identical, but biologically distinct tumor entities. Group-A (EPN_PFA) tumors have a poor prognosis and require intensive therapy. In contrast, group-B tumors (EPN_PFB) exhibit excellent prognosis and the current consensus opinion recommends future clinical trials to test the possibility of treatment de-escalation in these patients. Therefore, distinguishing these two tumor subtypes is critical. EPN_PFA and EPN_PFB can be distinguished based on DNA methylation signatures, but these assays are not routinely available. We have previously shown that a subset of poorly prognostic childhood EPN_PF exhibits global reduction in H3K27me3. Therefore, we set out to determine whether a simple immunohistochemical assay for H3K27me3 could be used to segregate EPN_PFA from EPN_PFB tumors. We assembled a cohort of 230 childhood ependymomas and H3K27me3 immunohistochemistry was assessed as positive or negative in a blinded manner. H3K27me3 staining results were compared with DNA methylation-based subgroup information available in 112 samples [EPN_PFA (n = 72) and EPN_PFB tumors (n = 40)]. H3K27me3 staining was globally reduced in EPN_PFA tumors and immunohistochemistry showed 99% sensitivity and 100% specificity in segregating EPN_PFA from EPN_PFB tumors. Moreover, H3K27me3 immunostaining was sufficient to delineate patients with worse prognosis in two independent, non-overlapping cohorts (n = 133 and n = 97). In conclusion, immunohistochemical evaluation of H3K27me3 global reduction is an economic, easily available and readily adaptable method for defining high-risk EPN_PFA from low-risk posterior fossa EPN_PFB tumors to inform prognosis and to enable the design of future clinical trials.

Keywords

Childhood ependymoma Epigenetics H3K27me3 Molecular subgrouping 

Notes

Acknowledgements

We thank Dr. Paul Mischel for insightful comments. This work was supported by grants from NCI K08 CA181475 (S.V.), Mathew Larson Foundation (SV), Sidney Kimmel Foundation (SV), Doris Duke Foundation (SV); Making Headway Foundation (M.S. and M.A.K.), the Sohn Conference Foundation (M.S. and M.A.K.), the Friedberg Charitable Foundation (M.S. and M.A.K.) and Canadian Children’s Cancer & Blood Disorders-C17 grant (JH). Research reported in this publication was supported by the National Cancer Institute of the National Institutes of Health under Award Number P30CA046592 by the use of the following Cancer Center Shared Resource(s): Biostatistics. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.

Author contributions

PP, JC, VR, YS, MJS and SR analyzed data. YS and MJS are biostatisticians. PP, AJR and SV wrote the manuscript. DH and FY performed H3K27me3 staining. JC, DH, CD, SY, MrS, FJR, MaS, CH, CMH, AK, AJR and SV are neuropathologists and evaluated tumor samples. PP, JC, AB, CC and JMB captured samples in a blinded manner. Cases and clinical data were provided by CD, SY, JH, AM, MP, SJC, MrS, FJR, MS, MAK, AMS, CMH, ASC, BW, DJ, LLC, SZ, DE, MaS, KS, NJ, PDM, MK, SMP, MDT, CH, AK and AJR. VR, MDT, LC, MK, SMP and AK performed DNA methylation analyses to subgroup tumors. All authors read and edited the manuscript.

Compliance with ethical standards

Conflict of interest

The authors declare no competing interests.

Supplementary material

401_2017_1752_MOESM1_ESM.docx (2.1 mb)
Supplementary material 1 (DOCX 2197 kb)

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Copyright information

© Springer-Verlag GmbH Germany 2017

Authors and Affiliations

  • Pooja Panwalkar
    • 1
  • Jonathan Clark
    • 1
  • Vijay Ramaswamy
    • 2
    • 3
  • Debra Hawes
    • 4
  • Fusheng Yang
    • 4
  • Christopher Dunham
    • 5
    • 6
  • Stephen Yip
    • 6
  • Juliette Hukin
    • 7
  • Yilun Sun
    • 8
  • Matthew J. Schipper
    • 8
  • Lukas Chavez
    • 9
  • Ashley Margol
    • 10
  • Melike Pekmezci
    • 11
  • Chan Chung
    • 1
  • Adam Banda
    • 1
  • Jill M. Bayliss
    • 1
  • Sarah J. Curry
    • 2
  • Mariarita Santi
    • 12
  • Fausto J. Rodriguez
    • 13
  • Matija Snuderl
    • 14
  • Matthias A. Karajannis
    • 15
  • Amanda M. Saratsis
    • 16
    • 17
  • Craig M. Horbinski
    • 18
  • Anne-Sophie Carret
    • 19
  • Beverly Wilson
    • 20
  • Donna Johnston
    • 21
  • Lucie Lafay-Cousin
    • 22
  • Shayna Zelcer
    • 23
  • David Eisenstat
    • 24
  • Marianna Silva
    • 25
  • Katrin Scheinemann
    • 26
    • 27
  • Nada Jabado
    • 28
    • 29
  • P. Daniel McNeely
    • 30
  • Marcel Kool
    • 9
    • 31
  • Stefan M. Pfister
    • 9
    • 31
    • 32
  • Michael D. Taylor
    • 33
  • Cynthia Hawkins
    • 34
  • Andrey Korshunov
    • 35
  • Alexander R. Judkins
    • 4
  • Sriram Venneti
    • 1
    • 36
  1. 1.Department of PathologyUniversity of MichiganAnn ArborUSA
  2. 2.Division of Haematology/Oncology, Hospital for Sick ChildrenUniversity of TorontoTorontoCanada
  3. 3.Programme in Neuroscience and Mental Health, Hospital for Sick ChildrenUniversity of TorontoTorontoCanada
  4. 4.Department of Pathology and Laboratory Medicine, Children’s Hospital Los AngelesKeck School of Medicine of University of Southern CaliforniaLos AngelesUSA
  5. 5.Division of Anatomic PathologyBritish Columbia Children’s HospitalVancouverCanada
  6. 6.Department of Pathology and Laboratory MedicineUniversity of British ColumbiaVancouverCanada
  7. 7.Divisions of Neurology and Hematology and Oncology, Children’s and Women’s Health Centre of B.CUniversity of British ColumbiaVancouverCanada
  8. 8.Department of BiostatisticsUniversity of MichiganAnn ArborUSA
  9. 9.Division of Pediatric NeurooncologyGerman Cancer Research Center (DKFZ)HeidelbergGermany
  10. 10.Department of Pediatrics, Children’s Hospital Los AngelesKeck School of Medicine University of Southern CaliforniaLos AngelesUSA
  11. 11.Department of PathologyUniversity of California San FranciscoSan FranciscoUSA
  12. 12.Department of Anatomic Pathology and Laboratory MedicineChildren’s Hospital of PhiladelphiaPhiladelphiaUSA
  13. 13.Department of PathologyJohns Hopkins University School of MedicineBaltimoreUSA
  14. 14.Department of PathologyNew York UniversityNew YorkUSA
  15. 15.Department of PediatricsMemorial Sloan Kettering Cancer CenterNew YorkUSA
  16. 16.Department of Neurological SurgeryNorthwestern University Feinberg School of MedicineChicagoUSA
  17. 17.Division of Pediatric NeurosurgeryAnn & Robert H. Lurie Children’s Hospital of ChicagoChicagoUSA
  18. 18.Department of Pathology and NeurosurgeryNorthwestern University Feinberg School of MedicineChicagoUSA
  19. 19.Division of Hematology-Oncology, Centre Hospitalier Universitaire Sainte-JustineUniversité de MontréalMontrealCanada
  20. 20.Division of Pediatric Hematology/Oncology, Stollery Children’s HospitalUniversity of AlbertaEdmontonCanada
  21. 21.Division of Pediatric Hematology/Oncology, Department of PediatricsUniversity of OttawaOttawaCanada
  22. 22.Division of Pediatric Hematology/OncologyAlberta Children’s HospitalCalgaryCanada
  23. 23.Division of Pediatric Hematology/Oncology, London Health Sciences CenterChildren’s HospitalLondonCanada
  24. 24.Department of Pediatrics and Medical GeneticsUniversity of AlbertaEdmontonCanada
  25. 25.Kingston General HospitalKingstonCanada
  26. 26.Department of PediatricsMcMaster UniversityHamiltonCanada
  27. 27.Division of Hematology/OncologyUniversity Children Hospital of Basel (UKBB) and University of BaselBaselSwitzerland
  28. 28.Department of PediatricsMcGill UniversityMontrealCanada
  29. 29.Department of Human GeneticsMcGill UniversityMontrealCanada
  30. 30.Division of Neonatal Pediatrics, Department of PediatricsDalhousie UniversityHalifaxCanada
  31. 31.German Cancer Consortium (DKTK)HeidelbergGermany
  32. 32.Department of Pediatric Oncology, Hematology and ImmunologyUniversity of HeidelbergHeidelbergGermany
  33. 33.Division of Neurosurgery, Arthur and Sonia Labatt Brain Tumor Research CentreThe Hospital for Sick ChildrenTorontoCanada
  34. 34.Pediatric Laboratory MedicineHospital for Sick ChildrenTorontoCanada
  35. 35.Department of Neuropathology, German Cancer Research Center (DKFZ)University Hospital Heidelberg and CCU NeuropathologyHeidelbergGermany
  36. 36.PathologyUniversity of Michigan Medical School, University of MichiganAnn ArborUSA

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