SATB1 expression levels in different disease stages of PCALCL are associated with the methylation status on the SATB1 promoter. (A) SATB1 mRNA expression in Mac-1 cells treated with a DNA demethylation reagent DAC was significantly upregulated, compared with cells treated with a histone deacetylase inhibitor TSA or the control DMSO solvent. *P < .05. Each experiment was repeated 2 times with 3 biological replicates.) (B) Schematic description of the SATB1 promoter and the sequencing results after bisulfite conversion. Mac-2A cells showed specific demethylation in the −733 to −297 region in the SATB1 promoter, compared with Mac-1 cells. DAC treatment in Mac-1 cells resulted in demethylation in this region, corresponding to upregulation of SATB1. Three independent PCR product clones were demonstrated for each cell. Solid dot, methylated CpG dinucleotide; circle, unmethylated CpG dinucleotide. (C) Quantitative methylation analysis on each CpG site in clinical samples with different stages of diseases. Methylation level 1 represents 100% methylated CpG dinucleotides on this site. Dotted line, 0.4. (D) Correlation between SATB1 mRNA expression and the average methylation level on all CpG sites. Pt, Patient no.