MAPK8 and neoplasm: Our results demonstrate that: (i) FKBP38 is upregulated in GBMNSs, compared to non-malignant human astrocytes (Figure 1); (ii) FKBP38 is required for the survival and self-renewal of GBMNSs (Figure 2); (iii) depletion of FKBP38 drives the cells toward apoptosis and autophagy (Figure 3 and Figure 4); (iv) FKBP38 inhibition-induced autophagy is regulated through the JNK/c-JUN–PTEN–AKT pathway (Figure 5); and (v) FKBP38 depletion extends the survival of tumor-bearing mice (Figure 6).