Isocryptotanshinone is a dual STAT3 and PTP1B (IC50 = 56.1 µM) inhibitor. Isocryptotanshinone inhibits STAT3 by binding to the STAT3 SH2 domain to block phosphorylation and nuclear translocation[1][2]. Isocryptotanshinone exerts its anti-proliferative effect via the induction of cell cycle arrest, apoptosis, and pro-death autophagy, through the regulation of STAT3, AKT/mTOR and MAPK signaling pathways. Isocryptotanshinone suppresses the xenograft gastric cancer (GC) tumor growth in BALB/c nude mice. Isocryptotanshinone can be used for cancer research, such as lung cancer, breast cancer and GC[1][3][4].