Effects of DNA methylation on expression of tumor suppressor genes and proto-oncogene in human colon cancer cell lines

Figure 1 5-aza-dC induced hypomethylation of the promoter of p16^INK4A gene in HT-29 cells. Lane 1, untreated; lane 2, 5-aza-dC treated; lane 3, untreated with bisulfite. MSP was performed with the specific primers described in the Materials and Methods.

Figure 2 Up-regulated mRNA level of p16^INK4A by 5-aza-dC in HT-29 cells. RT-PCR was performed as described in Materials and Methods. β-actin was used as a loading/amplification control.

Figure 3 5-aza-dC increased the transcription of p16^INK4A gene in Colo-320 (A) and SW1116 cells. Lane 1: mock treatment. Lanes 2-7: after 5-aza-dC treatment; lane 2: 2 μmol/L, 24 h; lane 3: 5 μmol/L, 24 h; lane 4: 10 μmol/L, 24 h; lane 5: 2 μmol/L, 72 h; lane 6: 5 μmol/L, 72h; lane 7: 10 μmol/L, 72 h. The density of bands shown in Table 3.

Figure 4 5-aza-dC increased the transcription of APC gene in Colo-320 (A) and SW1116 cells. Lane 1: mock treatment. Lanes 2-7: after 5-aza-dCtreatment; lane 2: 2 μmol/L, 24 h; lane 3: 5 μmol/L, 24 h; lane 4: 10 μmol/L, 24 h; lane 5: 2 μmol/L, 72 h; lane 6: 5 μmol/L, 72 h; lane 7: 10 μmol/L, 72 h. The density of bands shown in Table 4.