Figure 5 shows the measurement of gene expressions via real-time PCR on Dnmt1, Dnmt3a, and Dnmt3b in human oral cancer lines. For Dnmt1, there were no expression differences between NHOK and other cell lines (Figure 5(a)). However, Dnmt3a and Dnmt3b showed significantly higher expression levels in TW2.6 and Ca922 than others (Figures 5(b) and 5(c)). This evidence concerns the gene DNMT1 and lip and oral cavity carcinoma.