Figure 3
Correlation between SLC22A18 promoter methylation and SLC22A18 mRNA and protein expression. (A) SLC22A18 promoter methylation analysis. In patients 1, 8, 15 and 30, the SLC22A18 promoter was methylated in glioma and not the adjacent brain tissue. The SLC22A18 promoter is also methylated in U251 cells. T, glioma; N, adjacent brain tissue; m, methylated; u, unmethylated. (B) SLC22A18 RT-PCR mRNA expression in patients 1, 8, 15 and 30. GAPDH was used as an internal control. (C) Western blot of SLC22A18 protein expression in patients 1, 8, 15 and 30. ß-actin was used as an internal control. Both SLC22A18 mRNA and protein expression are significantly downregulated in gliomas with promoter methylation, compared to the corresponding adjacent normal brain tissues.