DPP4 and glioblastoma: In fact, the BS149 cell line generated from recurrent glioblastoma is more malignant than the other four glioblastoma cell lines (LN018, LN215, LN229, and LN319) and has higher mRNA levels of DPP4, ANPEP, and ENPEP (Figure 2A), further corroborating the potential oncogenic roles of ANPEP and ENPEP in GBM.