ESR2 and central nervous system cancer: Furthermore, as data from both the ERβ specific in vitro bioluminescence reporter assay (Fig. 4a) and the ERβ only expressing prostate cancer line DU-145 (Fig. 4b) established that 28 and ent-28 are ERβ agonists, we hypothesized that targeting ERβ with 28 or ent-28 in gliomas may establish a novel and highly efficacious therapy against this deadly brain tumor.