Young Zoon Kim
Background: Alteration of apoptosis is related with progression and recurrence of atypical meningiomas (AMs). However, no comprehensive study has been conducted regarding histone modification regulating apoptosis in AMs. This study was aimed to determine the prognostic values of certain apoptosis-associated factors, and examine the role of histone modification on apoptosis in AMs.
Materials and method: The medical records of 67 patients with AMs, as diagnosed during recent 13 years, were reviewed retrospectively. Immunohistochemical staining was performed on archived paraffin-embedded tissues for pro-apoptotic factors (CASP3, IGFBP, TRAIL-R1, BAX, and XAF1), anti-apoptotic factors (survivin, ERK, RAF1, MDM2, and BCL2), and the histone modifying enzymes (MLL2, RIZ, EZH1, NSD2, KDM5c, JMJD2a, UTX, and JMJD5).
Results: Twenty-six (38.8%) patients recurred during the follow-up period (mean duration 47.7 months). In terms of time-to-recurrence (TTR), overexpression of CASP3, TRAIL-R1, and BAX had a longer TTR than underexpression, and overexpression of Survivin, MDM2, and BCL2 had a shorter TTR than underexpression (P<0.05). Additionally, overexpression of MLL2, UTX, and JMJ5 had shorter TTRs than underexpression, and overexpression of KDM5c had a longer TTR than underexpression. However, in the multi-variate analysis of predicting factors for recurrence, underexpression of CASP3 (P<0.001), and BAX (P<0.001), and overexpression of survivin (P=0.007), and MDM2 (P=0.037) were associated with recurrence independently, but any enzymes modifying histone were not associated with recurrence.
Conclusion: This study suggests certain apoptosis-associated factors should be associated with recurrence of AMs, which may be regulated epigenetically by histone modifying enzymes.
