RT Journal Article SR Electronic T1 Peroxiredoxins and their expression in ependymomas JF Journal of Clinical Pathology JO J Clin Pathol FD BMJ Publishing Group Ltd and Association of Clinical Pathologists SP 12 OP 17 DO 10.1136/jclinpath-2012-201048 VO 66 IS 1 A1 Toomas Haapasalo A1 Kristiina Nordfors A1 Sally Järvelä A1 Eloise Kok A1 Pauli Sallinen A1 Vuokko L Kinnula A1 Hannu Kalervo Haapasalo A1 Ylermi Soini YR 2013 UL http://jcp.bmj.com/content/66/1/12.abstract AB Aims Peroxiredoxins I–VI (Prxs) have recently been shown to have a role in the tumorigenesis of astrocytic brain tumours. In some tumour types they are associated with Nrf2 (transcription factor NF-E2-related factor), a sensor of oxidative stress, and DJ-1 (also known as PARK7), a protein known to stabilise Nrf2. Methods We investigated the immunohistochemical expression of Prxs I–VI, Nrf2 and DJ-1 in a total of 76 ependymomas and their relationship with clinicopathological features of these tumours. Results There was a significant expression of all Prxs except Prx IV in the ependymomas. Strong nuclear and cytoplasmic expression of Nrf2 could be detected in these tumours. Prx I expression was significantly associated with cytoplasmic and nuclear Nrf2 expression. Prx I expression was also associated with tumour site, with cerebellar ependymomas having a lower expression of Prx I than other tumours. DJ-1 did not associate with Prxs but nuclear DJ-1 had an inverse association with nuclear Nrf2. Cytoplasmic DJ-1 associated with worse survival in ependymoma patients. Conclusions This study indicates that oxidative mechanisms as reflected by Nrf2 expression are highly activated in ependymomas. Prxs, especially Prx I, were associated with Nrf2 expression, suggesting a role for Nrf2 in Prx I synthesis in ependymomas. While DJ-1 did not associate with any of the Prxs, its expression was associated with worsened patient survival and could have a role as a prognostic marker in ependymomas.