Bisulfite sequencing analysis. (A) Summary of bisulfite sequencing analysis of methylation status in cell lines and control tissues of the selected genes. (B) Methylation-specific PCR analysis of DHRS3. M, methylation-specific reaction; U, non-methylation-specific reaction. Samples from left to right: SK-N-AS, SK-N-BE(2), SK-N-DZ, SK-N-FI, Kelly, NB69, IMR-32, SK-N-SH, SH-SY-5Y, adrenal, blood lymphocytes (3 samples), unmethylated control, methylated control and negative PCR control. Most of the NB cell lines are partially methylated, as they show both methylated and unmethylated products. NB69 is although completely methylated, and SK-N-DZ and SK-N-SH unmethylated (although weak methylated bands can be detected by careful inspection, which could reflect a low level of methylation in these samples). (C) Examples of bisulfite sequencing of SCNN1A and KRT19. Cytosines/tymines in the CpG dinucleotide are underlined. C in the sequence indicates methylated CpG sites and T unmethylated. SCNN1A, top sequence IMR-32, bottom adrenal; KRT19, top sequence SH-SY-5Y and bottom, blood lymphocytes.