Peroxiredoxins and their expression in ependymomas.
OBJECTIVE
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.
Department of Pathology, Fimlab Laboratories, Tampere University Hospital, and University of Tampere, Tampere, Finland.
Toomas
T
Haapasalo
Kristiina
K
Nordfors
Sally
S
Järvelä
Eloise
E
Kok
Pauli
P
Sallinen
Vuokko L
VL
Kinnula
Hannu Kalervo
HK
Haapasalo
Ylermi
Y
Soini
D000293:Adolescent; D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000378:metabolism; D001932:Brain Neoplasms / Q000378:metabolism* / Q000401:mortality / Q000473:pathology / Q000601:surgery; D002467:Cell Nucleus / Q000378:metabolism / Q000473:pathology; D002648:Child; D002675:Child, Preschool; D003593:Cytoplasm / Q000378:metabolism / Q000473:pathology; D004806:Ependymoma / Q000378:metabolism* / Q000401:mortality / Q000473:pathology / Q000601:surgery; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D051267:NF-E2-Related Factor 2 / Q000378:metabolism; D009364:Neoplasm Recurrence, Local / Q000378:metabolism / Q000401:mortality / Q000473:pathology; D015513:Oncogene Proteins / Q000378:metabolism; D018384:Oxidative Stress; D054464:Peroxiredoxins / Q000378:metabolism*; D000071617:Protein Deglycase DJ-1; D015996:Survival Rate; D055815:Young Adult
D014408:Biomarkers, Tumor; D047908:Intracellular Signaling Peptides and Proteins; D051267:NF-E2-Related Factor 2; C495635:NFE2L2 protein, human; D015513:Oncogene Proteins; D054464:Peroxiredoxins; C105131:PARK7 protein, human; D000071617:Protein Deglycase DJ-1