Figure 2.

Dexamethasone downregulates expression of Lck. (a) WEHI7.2 cells were treated with vehicle or varying concentrations of dexamethasone for 24 h. Lck mRNA was measured by real-time PCR. Values represent triplicate measurements and are relative to the vehicle-treated sample. β-actin was used as an endogenous control for each PCR reaction. (b) Primary thymocytes (5.0 × 10⁶ cells per ml) were harvested from adult B6 mice and treated with vehicle or dexamethasone for 12 and 24 h. Lck mRNA was measured by real-time PCR as described above. (c) WEHI7.2 cells were treated with vehicle or 10⁻⁶ M dexamethasone with and without the glucocorticoid receptor antagonist RU486 at equal and excess concentrations for 24 h. Lysates were subjected to western blotting for Lck. (d) Thymocytes were treated with vehicle or 10⁻⁸ M dexamethasone for 12 h and subjected to western blotting for Lck. (e) CEMC7 cells (T-ALL) were treated with varying concentrations of dexamethasone for 48 and 72 h and subjected to western blotting for Lck. β-Actin was used as a loading control. Data are representative of multiple independent experiments. Error bars indicate the difference between maximum and mean values from triplicate measurements