Table I.

Methylation density of the NAT1 gene after knockdown of H19 in MCF-7 and MCF-7R cells.

	Methylation density (%)
Cell line	Non-TF	NS siRNA	siRNA H19
MCF-7	30.78±2.2	31.61±0.35	36.5±2.92
MCF-7R	66.11±0.75a	63.84±2.02	26.39±0.75b

MCF-7 and MCF-7R cells were transfected with siRNA H19 and the methylation status of the NAT1 gene promoter in the cells was examined using a bisulfite genomic sequencing PCR assay. Data were obtained from three separate experiments and are presented as the mean ± SEM. A one-way ANOVA and Tukey's post hoc test were used for analysis.

^aP<0.001 vs. MCF-7/non-TF;

^bP<0.001 vs. MCF-7R/non-TF. NAT1, N-acetyltransferase 1; MCF-7R, tamoxifen-resistant MCF-7 cells; non-TF, non-transfected; NS, non-specific; siRNA, small interfering RNA.