Figure 2.
Expression levels and methylation profiles of CYP3A4 after epigenetic reprogramming. (A) Relative expression levels of the CYP3A4 gene in reprogrammed hepatic cells and human hepatocytes. The histograms show the means ± SD and statistical significance (reprogrammed vs control) was ***P < .001 (t test). (B) Comparison of human hepatocytes and hepatoma cells with regard to the methylation levels (%) of the CYP3A4 promoter by combined bisulfite restriction analysis (COBRA). (C) CYP3A4 methylation after epigenetic reprogramming. Reprogrammed HepG2 and Hep3B cells were treated with 5-AZA (2.5 μmol/L) for 10 days before genomic DNA extraction. Representative gels for 3 distinct COBRA experiments are shown. Statistical significance: ***P < .001 (t test). H, hepatocytes; M, methylated; Reprog, reprogrammed; U, unmethylated.