GGC alters STAT3 phosphorylation substantially.
We examined the impact of GGC on STAT3 activation using western blotting (Fig. 1C). We noted that GGC suppressed the phosphorylation of STAT3 (Tyr 705), but had minimal impact on STAT5 activation (Fig. 1G). We next determined whether GGC can modulate DNA binding property of STAT3. As shown in Fig. 1D, GGC can effectively reduce DNA binding ability as well as attenuate STAT3 translocation from the cytoplasm to nucleus in A549 cells (Fig.1E).