Figure 1

Induction of DLC-1 gene expression by HDAC inhibitors is via an activation of DLC-1 promoter in human gastric cancer cells. (A) The basal activity of DLC-1 promoter in gastric cancer cells. The DLC-1 promoter luciferase construct (-577/+117-pGL3b) was transiently transfected into gastric cancer cells for 24 h. Luciferase activity was measured and normalized by protein concentration. Data are representative of three independent experiments performed in triplicate. Expression of DLC-1 mRNA of each gastric cancer cells is shown in the top of the graph. (B) HDAC inhibitors induce DLC-1 gene expression. SNU-5 cells were treated with 330 nM TSA, 5 mM NaBu, or 1 µM SK-7068 and cultured for 12 h. DLC-1 and β-actin mRNA expression was determined by RT-PCR as describe in "Materials and Methods" (C). TSA treatment increases the DLC-1 promoter activity. SNU-5 and SNU-668 cells were transiently transfected with empty reporter vector (pGL3b) or DLC-1 promoter luciferase construct (-577/+117-pGL3b) for 24 h followed by treatment with DMSO or 330 nM TSA for 12 h. Luciferase activity was measured and normalized by protein concentration. The data represent the combined results of three independent experiments performed in triplicate.