Prognostic Significance of P16, EZH2, FOXJ1, and Tenascin Expression in Pediatric Ependymoma

Abstract

Background: The prognosis of pediatric ependymomas remains poor, with treatment being predominantly based on surgery with or without radiotherapy. The lack of robust therapeutic molecular markers for clinical use has hampered attempts to improve survival from ependymomas. This study aimed to assess the prognostic significance of p16, enhancer of zeste homolog 2 (EZH2), forkhead box protein J 1 (FOXJ1), and tenascin in pediatric ependymomas by evaluating their immunohistochemical expression and comparing them with clinical outcomes. Methods: A total of 22 children (< 14 years) with ependymoma were retrospectively analyzed for the expression of p16, EZH2, FOXJ1, and tenascin by immunohistochemical staining. Kaplan-Meier analysis was used to evaluate the association between immunohistochemical marker expression and patient survival. Results: Higher expression of p16, EZH2, FOXJ1, and tenascin was observed in 59.0%, 36.3%, 40.9%, and 68.1% of the ependymoma samples, respectively. Patients with p16-positive and p16-negative tumors had an overall median survival time of 5.38 and 3.38 years and an overall cumulative survival rate of 44.5% and 36.5%, respectively. P16 negativity was significantly associated with poorer outcome (P = 0.009). No relationship was observed between EZH2, FOXJ1, and tenascin expression and overall survival (P = 0.904, 0.844, and 0.646, respectively). Conclusions: Loss of p16 expression was associated with poor prognosis and may be used for risk stratification. Limitations of the present study include its small sample size and variable sensitivity of different antibody clones and detection methods. Int J Clin Pediatr. 2020;9(3):67-71 doi: https://doi.org/10.14740/ijcp385