GSTK1 and glioma: According to the regression coefficients of the 13 genes, we defined glioma-redox risk score (GRORS) as following: 0.192 × MTHFS + 0.151 × ALDH3B1 + 0.076 × GGT5 + 0.070 × DHFR + 0.035 × FKBP1B + 0.034 × ADH5 + 0.029 × NCF2 + 0.016 × GSTK1 + 0.009 × CASP3 + 0.008 × GPI + 0.006 × PDIA4 − 0.010 × MTHFD2 − 0.014 × TXN2.