The association between NRF2 transcriptional gene dysregulation and IDH mutation in Grade 4 astrocytoma

Abstract

Abstract Objectives Nuclear factor erythroid-2-related factor 2 (NRF2), a transcriptional gene factor related to nuclear factor erythroid 2, plays a role in the development of gliomas with isocitrate dehydrogenase (IDH) mutation. Its impact on tumour recurrence has seldom been investigated. Methods A group of 34 patients diagnosed with Grade 4 astrocytoma was included in a retrospective cohort. NRF2 protein and gene expressions were assessed using different profiling assays. The association between IDH mutation, NRF2 expression, and tumor recurrence was investigated. Results The mean patients’ age in this study was 50 years. Out of the total number of tumors analyzed, 21 of them had IDH mutation. NRF2 protein expression was found to be overexpressed in 27 tumors and reduced in 7 tumors. Additionally, NRF2 gene was upregulated in 24 tumors and downregulated in 10 tumors. Insignificant statistical difference was observed in recurrence-free interval (RFI) between patients with upregulated or downregulated NRF2 gene or protein expressions (p-value>0.05). However, this relationship is distinctive when NRF2 expression was compared to IDH mutation. Tumors with different levels of NRF2 expressions and IDH mutations showed significant statistical variation in RFI (p-value=0.001). There was insignificant impact on RFI among patients receiving different chemotherapies (TMZ or TMZ plus) who had abnormal NRF2 gene activities (p-value=0.97). Conclusions WHO-Grade 4 astrocytoma with IDH mutation and altered NRF2 expression showed a delayed tumor recurrence compared to IDH-wildtype glioblastoma.