Figure 3

The functional effect of ectopic miR-143 expression in 228 and SW480 cells. (A) Ectopic miR-143 expression suppresses cell proliferation in colon cancer cells. Cells were transfected with miR-143 precursor or control precursor for 24 h. Cell proliferation at 5 days after transfection was assessed by MTT assay. The miR-143 expression was examined by qPCR (Mann–Whitney test, ^*P<0.05, ^**P<0.01). Relative cell proliferation was compared with the corresponding control inhibitor or precursor (Mann–Whitney test, ^*P<0.05). (B) Ectopic miR-143 expression reduced the anchorage-independent growth of cancer cells using soft-agar colony formation assay. Cells were plated in 0.3% noble agar for 3 weeks. The number of colonies was counted after staining with 0.05% crystal violet (Mann–Whitney test, ^*P<0.05). Ectopic miR-143 expression reduced both (C) mRNA and (D) protein expression of DNMT3A. Cells were transfected with miR-143 precursor or with control precursor for 24 h, and then lysed for RNA or protein extraction. DNMT3A mRNA was detected by real-time qPCR (Mann–Whitney test, ^*P<0.05, ^**P<0.01) and protein expression was detected by western blotting with an anti-DNMT3A antibody. β-Actin was used as a loading control.