Figure 2.

Analysis of Stat3 activation in human cutaneous SCC tissues. Nuclear extracts were generated from surgical tissues. In case 5, normal skin, primary lesion (P), and metastatic lesion (M) of SCC from the same patient were analyzed for Stat3 activation using EMSA with a ³²P-labeled DNA probe to detect binding activity of Stat3. Specificity of the DNA-binding complex was evaluated by competition with excess unlabeled Stat3 oligonucleotide (cold). Stat3 activation of the primary lesions of the other 3 cases was also analyzed. Three of the 4 primary lesions and a metastatic SCC showed the strong DNA binding activity of Stat3 while little activation was seen in normal skin samples examined and in one primary SCC lesion (case 6). Data of normal skin are representative of 4 normal skin samples.