SH-4-54 is an inhibitor of signal transducer and activator of transcription 3 (STAT3; IC50 = 4.7 μM for STAT3 homodimer DNA binding activity). It selectively inhibits STAT3 homodimer over STAT1 and STAT5 homodimer and STAT3:STAT1 heterodimer DNA binding in EGF-stimulated NIH3T3/hEGFR nuclear extracts containing activated STAT1, STAT3, and STAT5 and decreases STAT3 iNOS, Survivin, and Bcl-2 promoter occupancy in MDA-MB-231 cells. SH-4-54 inhibits growth of glioma, breast, and prostate cancer cell lines that express constitutively active STAT3 (IC50s = 1-7.4, 3.8-4.5, and 5.3-5.8 μM, respectively). In vivo, SH-4-54 (3 mg/kg per day) inhibits tumor growth in the U251MG glioma and MDA-MB-231 breast cancer mouse xenograft models.
4-[[(4-Cyclohexylphenyl)methyl][2-[methyl[(2,3,4,5,6-pentafluorophenyl)sulfonyl]amino]acetyl]amino]benzoic Acid acts as a STAT 3 and STAT5 inhibitor. STAT 3 is unusually active in glioblastoma and plays a crucial role in tumor growth
