PCNA and glioblastoma: In particular, there are five genes (GNRH1, GNRH2, NPFF, NMU, and TAC3) annotated with “Gastrin-CREB signalling pathway via PKC and MAPK” (Corrected P-value = 2.87E-05) and which could regulate glioblastoma (GBM) tumour cell proliferation by modulating the expression of three key cell cycle factors, cyclin B, D and proliferating cell nuclear antigen (PCNA).