To determine if IT treatment inhibited IGF-1-induced STAT3 activation, melanoma cells were grown in serum-free medium for 24 h, and then pretreated with or without IT (20, 40 and 80 μM) for 2 h, followed by addition of IGF-1 (20 ng/mL) for 1 h. Here, IGF1 is linked to melanoma.