Fig. 3

STAT3 knockdown induced loss of mitochondrial membrane potential in ECA109 cells. The cells were stained with JC-1 dye and visualized under a fluorescence microscope 24 h after transfection. The ECA109 cells in the pSi-Scramble group and untreated group exhibited red cell staining which suggested that they had normal high membrane potentials. While, pSi-STAT3 treatment caused a significant loss of JC-1 red fluorescence, that is, loss of mitochondrial membrane potential after transfected with pSi-STAT3 for 24 h, which correlated to apoptosis (original magnification, ×200)