In GBM, circHEATR5B was expressed at low levels and could suppress glycolysis, whereas HEATR5B mRNA levels showed no significant differences and could not be regulated by ZCRB1, indicating that it is circHEATR5B but not HEATR5B mRNA that exerts glycolytic inhibition in GBM cells under the regulation of ZCRB1. Here, HEATR5B is linked to glioblastoma.