Dominant negative activity of GRβ mutants. Fold changes of mRNA level of the genes GILZ and S100P, regulated by hGRα (mock) in the presence of 100 nM DEX, were calculated after transient transfection of hGRβ, hGRβ (F602S), hGRβ (V571R), and hGRβ (V575R) into U-2 OS cells stably expressing hGRα. Experiments were performed in triplicate, and the data are represented as means ± standard errors of the mean (***, P ≤ 0.001).