Effects of 5-aza-dC on the DNA methylation and expression of heparanase in MCF-7 and MDA-MB-435 cells.

<p>(A) MSP analyses showed that all the three different concentrations of 5-aza-dC (0.5 µM, 5 µM and 10 µM) can attenuate the DNA methylation of heparanase in a dose-dependent manner, especially in MCF-7. The untreated cells served as a control. (B and C) Pyrosequencing results of DNA methylation changes in MCF-7 and MDA-MB-435 cells with 5-aza-dC treatment. Quantitative analysis showed that DNA methylation of heparanase decreased significantly in a dose-dependent manner, especially in MCF-7. (D) Analyses of mRNA abundances in MCF-7 and MDA-MB-435 cells treated with different concentrations of 5-aza-dC (0.5 µM, 5 µM and 10 µM) by semi-quantitative RT-PCR (left panel) and Real-time RT-PCR (right panel). (E) Western blot detections of of heparanase expression in MCF-7 and MDA-MB-435 cells treated with different concentrations of 5-aza-dC (0.5 µM, 5 µM and 10 µM). (*<i>p</i><0.05, **<i>p</i><0.01 compared with the control.). Abbreviations: MSP: methylation-specific PCR; MSP-U: amplicons for unmethylated MSP; MSP-M: amplicons for methylated MSP.