(A) Methylation status of the TGFBI promoter in lung and prostate tumor cell lines using the P5/P6 primer pair in MSP. (B) Induction of TGFBI expression in lung and prostate tumor cell lines by TGF-β1 determined by Northern blotting. Cells were treated with TGF-β1 at 5 ng/ml for 6 hours. Total RNAs were isolated and used for determining the mRNA level of the TGFBI gene before and after treatment. (C) TGFBI mRNA level in lung and prostate tumor cell lines with or without demethylating treatment determined by real-time RT-PCR. Cells were treated with Aza-CdR at 10 μM for 4 days with medium changed each day. Relative quantification of the TGFBI expression was performed by using real-time PCR, calibrated and normalized to its expression in DU145 cells. (D) TGFBI protein level in lung and prostate tumor cell lines with or without demethylating treatment examined by Western blotting.