Transcription Factor Sp1 Is Involved in Expressional Regulation of Coxsackie and Adenovirus Receptor in Cancer Cells
Figure 5
Effects of Sp1 or MTM on TSA-induced CAR promoter activity and mRNA expression. HepG2 (a, b) and MCF-7 (c) cells were pretreated with either MTM or DMSO for 30 min and followed by TSA treatment for 24 h. The mRNA expressions of CAR and GAPDH were examined by Semiquantitative RT-PCR. The extent of histone3 acetylation with actin used as a loading control was analyzed by western blotting. In contrary to (a), CAR mRNA expression was examined depending on TSA concentration with fixed concentration of MTM (c). The mRNA levels of lane1 were set to 1.0. (d) MCF-7 cells were transfected with the core promoter reporter construct and β-galactosidase and treated as in (c). The relative luciferase activity was determined. Bars represent S. D. Effects of WT-Sp1 and DN-Sp1 overexpression on CAR expression. (e) MCF-7 cells were transfected with WT-Sp1 (0.1, 0.25, 0.5, and 1 μg), treated with TSA (50 ng/mL) for 24 h, and examined for CAR mRNA expression by Semiquantitative RT-PCR. Relative expression of CAR mRNA to GAPDH was calculated based on the band intensity. (f) Similarly, HCT116 cells were transfected with DN-Sp1 (0.1, 0.25, 0.5, and 1 μg) in the absence of TSA, and relative expression of CAR mRNA was determined. The mRNA levels of lane1 were set to 1.0.
