Figure 3

Transient transfection of Mel-18 in SGC-7901 cells results in the downregulation of BMI1 and increased senescence in a dose-dependent manner. A) Transient transfection of Mel-18 results in increased senescence in a dose-dependent manner as determined by SA-β-gal staining analysis. SGC-791 cells were transfected with 0, 1.5, and 3 μg of Mel-18 overexpressing plasmid and analyzed for the induction of senescence using SA-β-gal assay. B) Senescent cells (SA-β-gal positive) from three different experiments were counted and plotted. C) Transient transfection of Mel-18 in SGC-7901 cells results in the dose-dependent downregulation of BMI1 as determined by Western blot analysis, β-actin serves as internal control ( upper panel: Mel-18, BMI1, and β-actin were detected by Western blot; lower panel: quantification of the levels of Mel-18 and BMI1. The levels of Mel-18 and BMI1 were quantified by densitometric analysis of signal present in each lane using ImageJ 1.37v software (NIH, Bethesda, USA) and normalized to β-actin signal of each lane, and plotted. ).