Effects of glucocorticoids on the growth and chemosensitivity of carcinoma cells are heterogeneous and require high concentration of functional glucocorticoid receptors

Figure 3 Increased drug resistance to cisplatin in pS-hGR-transfected AGS. AGS cells were transfected with pS-hGR and MTT assay were performed. A: GR number measured by [³H]-labeled ligand binding assay. Pool: AGS/GR-pool; AGS cells transfected with pS-hGR, pooled cells. c1: AGS/GR-c1; AGS cells transfected with pS-hGR, single cell cloned, clone 1. c2: AGS/GR-c2; AGS cells transfected with pS-hGR, single cell cloned, clone 2. Mock: AGS/empty vector; AGS cells transfected with empty vector. c3: AGS/GR-c3; AGS cells transfected with pS-hGR, single cell cloned, clone 3; B-D: Pretreatment with DEX 1 μmol/L for 3 h diminished cisplatin cytotoxicity in AGS/GR-pool, AGS/GR-c1, and AGS/GR-c2 cells; E and F: Pretreatment with DEX 1 μmol/L for 3 h had no effect on the cisplatin cytotoxicity in AGS/empty vector cells and AGS/GR-c3. All values represent mean±SD of six separate wells.