To gain more detailed insight about the role of PFKFB3-4 and PFKFB3-5 in glioblastomas, we employed the U87 glioblastoma cell line and investigated the knockdown and overexpression of these splice variants in relation to viability and proliferative capacity of U87 cells as a read out. Here, PFKFB3 is linked to glioblastoma.