S3I-201

Uses

A chemical probe inhibitor of STAT3 with an IC50 of 86 μM.

Uses

S3I-201 has been used as a signal transducer and activator of transcription 3 (STAT3) inhibitor:

• to confirm the role of STAT3 phosphorylation in interleukin (IL)-33 production in lung epithelial cells and IL-22 mRNA expression in sorted group 3 innate lymphoid cells (ILC3s)
• to study the cellular response of STAT3 triggered by β-hexaclorocyclohexane (β-HCH) in various cell lines
• to examine the influence of STAT3 in response to angiotensin II (ang II) on induction of fibrotic proteins in kidney epithelial cells

Uses

S2I-201 is a small molecule inhibitor that provides a pathway to rational combination therapies for Melanoma.

Definition

ChEBI: An amidobenzoic acid obtained by formal condensation of the carboxy group of [(4-methylbenzene-1-sulfonyl)oxy]acetic acid with the amino group of 4-amino-2-hydroxybenzoic acid.

Biological Activity

s3i-201 is a selective inhibitor of stat3 with ic50 value of 86 μm [1].in the in vitro stat3 dna-binding assay, s3i-201 showed potent inhibition of the stat3 dna-binding activity with an average ic50 of 86 μm. in the emsa assay, s3i-201 selectively inhibited stat3 dna-binding activity over that of stat1 and stat5. it suppressed the complex formation of stat1-stat3 and stat1-stat1 with ic50 values of 160 and > 300 μm, respectively. besides that, the unphosphorylated, inactive stat3 monomer was found to restore the stat3 dna-binding activity inhibited by s3i-201, suggesting that the inhibition was independent on the activation status. in nih 3t3/v-src fibroblasts, s3i-201 inhibited the constitutive activation of stat3 and reduced the ptyr-705 stat3 levels. moreover, s3i-201 was found to significantly induce apoptosis in cells with constitutively active stat3 at concentration of 30–100 μm. s3i-201 also reduced the expression of cyclin d1, bcl-xl and surviving in these cells [1].

Biochem/physiol Actions

S3I-201 is a cell-permeable Stat3 inhibitor that binds to the Stat3-SH2 domain, prevents Stat3 phosphorylation/activation, dimerization, and DNA-binding.

storage

-20°C

References

[1] siddiquee k, zhang s, guida w c, et al. selective chemical probe inhibitor of stat3, identified through structure-based virtual screening, induces antitumor activity. proceedings of the national academy of sciences, 2007, 104(18): 7391-7396.