DNA methylation of the AR gene is associated with loss of AR protein expression in breast cancer cells. (a) DNA methylation status of breast cancer cell lines. Three regions of AR were assessed by MS-HRM, overlapping Regions 1 and 2 in the AR minimal promoter and Region 3 at the translational start site (refer to Figure 1). Region 4 was assessed by Sequenom MassARRAY. Data represent the average of two independent experiments. (b) AR mRNA expression in breast cancer cell lines was assessed by qPCR. Expression is shown relative to β-actin and bars represent the mean ± standard deviation of two independent experiments.