(a) WB of RUNX3 protein expression after U87-MG cells transfection with pcDNA3-RUNX3 construct. NTC: nontransfected cells lysate; 1: cells transfected with 100 ng of pcDNA3-RUNX3 vector; 2: cells transfected with 50 ng of pcDNA3-RUNX3 vector. Equal amount of total protein extract (60 Î¼g) was loaded per each gel lane. The same amount of cell (b) RUNX3 promoter methylation status in U87-MG cells. (c) Results from glioblastoma U87-MG cells viability assay applying MTT test after 24 h of 100 ng of DNA transfection. RUNX3: RUNX3 gene in pcDNA3 expression vector (pcDNA3-RUNX3); GFP: green fluorescing protein in pcDNA4TO expression vector (pcDNA4TO-GFP); pcDNA3: empty (control) vector; NTC: nontransfected cell control. Overexpression of RUNX3 significantly decreased U87-MG cell viability starting from 50 ng of vector used as compared to the cells transfected with GFP vector. Moreover even bigger effect of decreased cell viability was obtained when 100 ng of RUNX3 was transfected.