Figure 1. DXR induces up-regulation of RGS6 in human cancer cell lines.
A. DXR treatment (1 μM, 24 h) induces up-regulation of endogenous RGS6 protein levels in U-87 and MCF-7 human cancer cells. A representative Western blot of three independent experiments is shown. B. DXR dose-dependently activates transcription from the RGS6 gene promoter in U-87 and MCF-7 cells. The human RGS6 promoter (bp −1450 to +52) in pGL3 basic vector was transfected into U-87 and MCF-7 cells. Thirty-six h after transfection, cells were then treated with indicated concentrations of DXR for 6 h. Luciferase activity was determined as described under “Material and Methods.” The luciferase activity of untreated (0 μM DXR) cells was set as 1. Results represent means ± S.E. of three independent experiments (*p < 0.001).