To elucidate the role of NANOG in malignancy, the difference in relative expression of NANOG between low-and high-grade gliomas was evaluated. Gene quantification was performed using real-time reverse transcription polymerase chain reaction from 29 isolated RNA samples of glioma resected during the surgery of patients in the Neurosurgery Department of FKUI-RSCM. The relative expression of NANOG in low-and high-grade gliomas was analyzed for normality and compared statistically. Statistical analysis showed no significant difference in NANOG expression between low-and high-grade glioma although there was a tendency for higher expression in the latter. The results support the indication of NANOG as a malignancy biomarker. However, further studies of NANOG expression in malignancy using a greater sample size or other methods may help confirm its role as a cancer biomarker that could be used as a potential therapeutic target or prognosis indicator. © 2018 Institute of Physics Publishing. All rights reserved.