STAT3 inhibitor 4m is an inhibitor of STAT3 and a derivative of celastrol .1 It inhibits the phosphorylation of STAT3 and decreases levels of the STAT3 target proteins survivin and myeloid cell leukemia 1 (Mcl-1) in HCT116 cells when used at concentrations of 0.75 and 1 µM. STAT3 inhibitor 4m inhibits the proliferation of A549, HCT116, and HepG2 cells (IC50s = 0.93, 0.61, and 1.79 µM, respectively). It induces apoptosis and cell cycle arrest at both the S and G2/M phases in HCT116 cells when used at a concentration of 5 µM. STAT3 inhibitor 4m (1-10 µM) also reduces the viability of human colorectal cancer organoids (CCOs).
1.Xu, S., Fan, R., Wang, L., et al.Synthesis and biological evaluation of celastrol derivatives as potent antitumor agents with STAT3 inhibitionJ. Enzyme Inhib. Med. Chem.37(1)236-251(2022)