Turkish Neurosurgery 2018 , Vol 28 , Num 1
New Clues in the Malignant Progression of Glioblastoma: Can the Thioredoxin System Play a Role?
Fatih ERDI1,Bulent KAYA1,Hasan ESEN2,Yasar KARATAS1,Siddika FINDIK2,Fatih KESKIN1,Bahadir FEYZIOGLU3,Erdal KALKAN1
1Necmettin Erbakan University, Meram Faculty of Medicine, Department of Neurosurgery, Konya, Turkey
2Necmettin Erbakan University, Meram Faculty of Medicine, Department of Pathology, Konya, Turkey
3Necmettin Erbakan University, Meram Faculty of Medicine, Department of Clinical Microbiology, Konya, Turkey
DOI : 10.5137/1019-5149.JTN.18991-16.2 AIM: To evaluate and compare the expression of thioredoxin reductase 1 (TrxR1) in primary and secondary glioblastoma samples.

MATERIAL and METHODS: Surgically resected human glioblastoma samples from 40 patients who underwent surgery at our institution were extracted from their histopathological specimens and divided into three groups. Ten histopathologically regular cerebral tissue samples, acquired from the non-neoplastic portion of the specimens, were assigned as the control group. Twenty specimens that included tumoral tissue from each type of glioblastoma (WHO grade IV, primary and secondary) were assigned as the primary and secondary glioblastoma groups. TrxR1 expression was analyzed by using both quantitative reverse transcription polymerase chain reaction (qRT-PCR) and immunohistochemistry. Isocitrate dehydrogenase 1 (IDH1) mutation was analyzed by immunohistochemistry. Ki-67 proliferative index and apoptosis were also analyzed by immunohistochemistry. The differences between the groups were statistically compared and the correlation between these parameters was analyzed.

RESULTS: The expressions of TrxR1 and Ki-67 values were significantly higher in primary glioblastoma. IDH1 mutation was significantly higher in secondary glioblastoma. TrxR1 expression was found to be highly correlated with the Ki-67 index. The apoptotic index was similar between primary and secondary glioblastoma.

CONCLUSION: This study showed a high TrxR1 expression in primary glioblastoma which could indicate a role of the Trx system in promoting the malignant progression by some complex processes. Keywords : Thioredoxin reductase 1, Isocitrate dehydrogenase 1, Glioblastoma, Primary, Secondary, Mutation

Corresponding author : Fatih ERDI, mfatiherdi@hotmail.com