Application： STA-21 has been used as a signal transducer and activator of transcription 3 (STAT3) inhibitor to study its effects on glioblastoma and primary glioblastoma cells. It has also been used as a STAT3 dimerization inhibitor to study its effects on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) production in human lung cancer cell line. Information Ochromycinone (STA-21) is a selectiveSTAT3inhibitor. Targets STAT3 In vitro In cells, STA-21 inhibits Stat3 DNA binding activity, Stat3 dimerization, and Stat3-dependent luciferase activity. STA-21 remarkably inhibits the growth and the survival of the breast carcinoma cells MDA-MB-231, MDA-MB-435s, and MDA-MB-468 that express persistently activated Stat3. In RH30 and RD2 cells, STA-21 also inhibits cell viability and growth and induced apoptosis through caspases 3, 8 and 9 pathways. In vivo In IL-1Ra–KO mice, STA-21 (0.5 mg/kg, i.p.) reduces the arthritis score and the incidence of arthritis by decreasing the proportion of Th17 cells and increasing the proportion of Treg cells expressing FoxP3. Cell Research(from reference) Cell lines：MDA-MB-231, MDA-MB-435s, MDA-MB-453, MDA-MB-468, MCF7, and Caov-3 cells Concentrations：20 or 30 μM Incubation Time：48 h