Expression of BCL2 gene in 1A9-M/BCL2 clones and effects of a dominant-negative form of Stat3 in 1A9-M/ST3D clones. (A) Total RNAs from parent 1A9-M or 1A9-M/BCL2 clones were isolated and subjected to Northern blot analysis using the cDNAs of BCL2 and β-actin as probes. (B) Whole cellular lysates were obtained from parent 1A9-M or 1A9-M/BCL2 clones and subjected to Western blot analysis using antimouse BCL2 or antihuman BCL2 antibody. (C) Parent 1A9-M cells and 1A9-M/ST3D (clone 1, 2, A, B) were electroporated with 30 μg of a reporter plasmid containing 4× APRE together with 30 μg of pRL-CMV-Rluc. The cells were serum-starved for 12 hours and then stimulated with 20 ng/mL IL-6 for 5 hours. The relative firefly luciferase activities were calculated by normalizing transfection efficiency according to the renilla luciferase activities. The results are shown as the mean ± SD of triplicated experiments. (□) Unstimulated; (▪) 20 ng/mL IL-6.