Figure 2. Role of DNMT3b in tumor growth in vitro and in vivo.

A. Effects of DNMT3b silencing vector on the level of DNMT3b in SCC4 and SCC25 demonstrated by Western blotting and immunochemical staining in vitro. Images of representative slides are shown and the arrow indicates positive staining of DNMT3b in cells. (C-V, cells with control vector; DNMT3b-SV, cells stably transfected with DNMT3b silencing vector; DNMT-I, cells treated with DNMT inhibitor). B. Effect of DNMT3b on the proliferation of oral cancer cells as determined by viable cell counting and colony formation. The same number of cells (10⁴) were plated in each plate on day 0 and allowed to grow in their respective cultures. We counted the number of viable cells after incubation for 2, 4 and 6 days. The Y axis represents the viable cell number. Point, means of three separate experiments; bars, SD. *, p<0.05. C. Cells were analyzed by FACS for DNA content under control conditions or with DNMT3b inhibition. The data was demonstrated by represented pictures. D. Effects of DBMT3b silencing vector on the levels of DNMT1 and DNMT3b evaluated by IHC and xenograft tumor growth. Each point represents the mean of three separate experiments; bars, SD; *, P<0.05. Representative pictures are shown.