Mechanistic characterization revealed that NSC-743380 and its analogues induced apoptosis in sensitive cancer cells [19-21], inhibited phosphorylation of RNA polymerase II [22, 23], induced sustained JNK activation by inhibiting its dephosphorylation [21], induced reactive oxygen species (ROS) accumulation [24], inhibited STAT3 phosphorylation, and suppressed cyclin D1 expression [20], suggesting that these compounds modulate multiple cancer-related targets. Here, STAT3 is linked to cancer.