Catalog No.S1155 Synonyms: NSC 74859

S3I-201 Chemical Structure

Molecular Weight(MW): 365.36

S3I-201 shows potent inhibition of STAT3 DNA-binding activity with IC50 of 86 μM in cell-free assays, and low activity towards STAT1 and STAT5.

Size Price Stock Quantity  
In DMSO USD 78 In stock
USD 70 In stock
USD 120 In stock
USD 370 In stock

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7 Customer Reviews

  • On day 1, 5-week-old female NOD/SCID mice were injected with 1 x 108 cells of the NOD/SCID repopulating T315I BCR-ABL1-positive leukemia UPN1 cells. On day 2, these mice were treated with either vehicle (n = 6), vismodegib (20 mg/kg per os; q.d.; n = 6), ponatinib (30 mg/kg; q.d.; n = 6), vismodegib (20 mg/kg per os; q.d.) + ponatinib (30 mg/kg; q.d.; n = 6) for each group. On day 28, mice were sacrificed for evaluation. CD19-positive cells from peripheral blood from each mouse have been shown. Histopathologic analysis of the bone marrow cavity from each treated mouse with UPN1 transplantation. Similar results were obtained in 2 independent experiments. H&E, hematoxylin and eosin.

    Clin Cancer Res 2013 19(6), 1422-32. S3I-201 purchased from Selleck.

    Inhibition of JAK1/2 with AG490 or STAT3 with S3I-201 leads to reduced STAT3 activation and reduced WASF3 levels. In contrast, treatment with Dasatinib (SRC inhibitor) or Gefitinib (EGFR inhibitor) does not significantly affect activated STAT3 or WASF3 levels.

    Carcinogenesis 2013 34(9), 1994-9. S3I-201 purchased from Selleck.

  • GBM6 cells were treated with WP1066 and S3I-201 at the indicated concentrations, and the expression of STAT3, pSTAT3, and p65 proteins was determined by immunoblotting. Ad-CSC, adherent CSC. 

    J Biol Chem 2013 288, 26167-76. S3I-201 purchased from Selleck.

    The inhibitors U0126, PP1 and S3I-201 reduce the colony-forming ability of KIF5B-RET positive cells. A549 cells carrying KIF5B-RET were diluted and seeded in 6-well plates, treated with DMSO, U0126 (MEK inhibitor) 10 uM, PP1 (SRC inhibitors) 5 uM or S3I-201(STAT3 inhibitors) 100 uM for 14 days. The total numbers of colonies, each containing more than 40 cells, were determined. (*P < 0.05, **P < 0.01, ***P < 0.001, Student's t test).

    Mol Cancer 2014 13:176. S3I-201 purchased from Selleck.

  • The survival phenotype of A549 cells dependents on transiently activation of STAT3 signaling pathway. A549 cells were mock-invaded (A549, medium alone as control) following treatment with or without NSC 74859 for 24 h. DMSO was used for control. Cell lysates were analyzed by immunoblotting with antibodies to pSTAT3, STAT3 (2 h), and β-actin.

    Microbes Infect 2014 16(1), 17-27. S3I-201 purchased from Selleck.

    (A) The expression and phosphorylation of STAT3 in DCs after inhibition by NSC74859 was measured by western blot. β-Actin was measured as an internal control. The results are representative of three independent experiments. The expression of PD-L1 in DCs after STAT3 inhibition by NSC74859. DCs were seeded at a density of 2 x 106per well in 6-well plates. NSC74859 (100 uM) and TGF-β (10 ng/ml) were added on day 4 of DC culture. Cells were harvested on day 6, and the expression of PD-L1 was analyzed by western blot and flow cytometry. (B) The expression of PD-L1 was measured by western blot. (C) Densitometric analysis from the above immunoblots is shown as a bar chart. Data are shown as the means ± SD from 3 replicate experiments. **P < 0.01 vs. control DCs; ##P < 0.01 vs. stimulated with TGF-β only.

    Int Immunopharmacol 2014 20(1), 117-23. S3I-201 purchased from Selleck.

  • proliferation of GBM6 monolayer and adherent CSC cultures was measured by MTT assay after treatment
    (72 h) with WP1066 or S3I-201 at the indicated concentrations. 

    S3I-201 purchased from Selleck.

Purity & Quality Control

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Biological Activity

Description S3I-201 shows potent inhibition of STAT3 DNA-binding activity with IC50 of 86 μM in cell-free assays, and low activity towards STAT1 and STAT5.
Features A chemical probe inhibitor of Stat3 activity.
STAT3 [1]
(Cell-free assay)
86 μM
In vitro

S3I-201 inhibits growth and induces apoptosis preferentially in tumor cells that contain persistently activated Stat3 by inhibiting Stat3·Stat3 complex formation and Stat3 DNA-binding and transcriptional activitie. Moreover, S3I-201 also inhibits the expression of the Stat3-regulated genes encoding cyclin D1, Bcl-xL, and survivin. [1] S3I-201 inhibits breast carcinoma MDA-MB-435, MDA-MB-453 and MDA-MB-231 cell lines with IC50 of 100 μM. In addition, the cells with impaired TGF-β signaling are four times as sensitive to the STAT3 inhibitor S3I-201. [2] A recent study shows that S3I-201 potentiates the antiproliferative effect of cetuximab in HepG2 and Huh-7 cells via the STAT3 signalling pathway. [3]

Cell Data
Cell Lines Assay Type Concentration Incubation Time Formulation Activity Description PMID
NCI-N87R NEXpe5dHfW6ldHnvckBCe3OjeR?= NUXkfndqPTBizszN NXzjVndxOTBvNkCg[C=> M4n6dIlvcGmkaYTzJHNVSVR|IHHjeIl3cXS7 MnHoNlU{Ojd3NkG=
GH3 MXnHdo94fGhiSX7obYJqfGmxbjDBd5NigQ>? NFrU[JI2OC1zMkWg{txO NU\VTHo5PzJiaB?= M1;QTYF1fGWwdXH0[ZMhfGinIHPlcIwh\3Kxd4ToJIlvKGFiZH;z[U1l\XCnbnTlcpQhdWGwbnXy NFvUVpUzPTd5NEWwNy=>
GC  M1e0bGdzd3e2aDDJcohq[mm2aX;uJGF{e2G7 M4TRbVUxNTF{NTFOwG0> NFL5UWQ4OiCq NHzZR|JifHSnboXheIV{KHSqZTDj[YxtKGe{b4f0bEBqdiCjIHTvd4Uu\GWyZX7k[Y51KG2jbn7ldi=> NHfZd4EzPTd5NEWwNy=>
H460  MXLBdI9xfG:|aYOgRZN{[Xl? MlT5NVAxyqCwTR?= M1rJTlI1yqCq NYPrPFJncW6mdXPld{Bk\WyuIHHwc5B1d3OrczDjc{11emWjdHXkJJdqfGhiQlXaNlM2 M1fnSFI1PDd{NUO4
A459 NFvldIZCeG:ydH;zbZMhSXO|YYm= NXnYcXdCOTBywrDuUS=> MnjENlTDqGh? MYLpcoR2[2W|IHPlcIwh[XCxcITvd4l{KGOxLYTy[YF1\WRid3n0bEBDTVp{M{W= M3S2Z|I1PDd{NUO4
H460  NXnPSmhqSXCxcITvd4l{KEG|c3H5 NHvyN|AyODEEoH7N MYeyOOKhcA>? M4r0W4VvcGGwY3XzJINmdGxiZHXheIgh[29vdILlZZRm\CC5aYToJGx[Ojl2MECy NITlWlgzPDR5MkWzPC=>
MT-2 MV;BdI9xfG:|aYOgRZN{[Xl? NYDm[ZpuPzVvM{CwJO69VQ>? MoLkNlQwPDhiaB?= MkPFd5VxeHKnc4Pld{Bk\WyuIIDyc4xq\mW{YYTpc44hcW5iYTDkc5NmNWSncHXu[IVvfCCvYX7u[ZIh[W6mIHnu[JVk\XNiY3XscEBieG:ydH;zbZPDqA>? NIiyS2czPDB7MEm5OS=>
HUT-102 MnLsRZBweHSxc3nzJGF{e2G7 NInj[5g4PS1|MECg{txO MWeyOE81QCCq NXLFT3JSe3WycILld5NmeyClZXzsJJBzd2yrZnXyZZRqd25iaX6gZUBld3OnLXTldIVv\GWwdDDtZY5v\XJiYX7kJIlv\HWlZYOgZ4VtdCCjcH;weI9{cXQEoB?= NIPoVYszPDB7MEm5OS=>
U373  M1;t[Gdzd3e2aDDJcohq[mm2aX;uJGF{e2G7 MYqxNlUh|ryP NYWzNWZtOjRiaB?= MX\EUXNQ Mlzh[Il{enWydIOgV3RCXDNic3nncoFtcW6pIHHu[EBxem:uaX\ldoF1cW:w MoP5NlQxPzB6MkC=
T-cell  NUDnPGRLT3Kxd4ToJGlvcGmkaYTpc44hSXO|YYm= NHLr[npKSzVyPUWwJO69VQ>? M{DKR|I1ODZ6N{Ox
H1299 NH\2NY9HfW6ldHnvckBCe3OjeR?= NEPTRZQ2OC9zMECg{txO M{P4OlQ5KGh? MWTzeZBxemW|c3XzJI1qWi17MnGg[ZhxemW|c3nvckBld3OnLXTldIVv\GWwdHz5 NEPYPJIzOzh{MEK1OC=>
H460  NYG0UG9vTnWwY4Tpc44hSXO|YYm= M1\EeVUxNzFyMDFOwG0> MV[0PEBp NWizUFY4cW6qaXLpeJMhfGinIGP0ZZQ{SyCrbnPy[YF{\WRibXnSMVkz[SCneIDy[ZN{cW:w NUPiclVlOjN6MkCyOVQ>
PLC/PRF/5  NYPhU5dZT3Kxd4ToJGlvcGmkaYTpc44hSXO|YYm= NHfKWFcyODBibl2= MmH3OFghcA>? MUPEUXNQ NIm1dIxqdmirYnn0d{B1cGViSVytOkB{fGmvdXzheIlwdiCycn;tc5Rm\CClZXzsJJBzd2yrZnXyZZRqd25? NF;BVYkzOzN4NEO4PS=>
Huh7 MkXIS5Jwf3SqIFnubIljcXSrb36gRZN{[Xl? MYexNFAhdk1? M3\RXFQ5KGh? M4\hd2ROW09? MkXLbY5pcWKrdIOgeIhmKEmOLU[gd5RqdXWuYYTpc44heHKxbX;0[YQh[2WubDDwdo9tcW[ncnH0bY9v NHG3dmQzOzN4NEO4PS=>
 U-373 MG M37Wd2N6fG:2b4jpZ4l1gSCDc4PhfS=> M{jPfFMwOTBizszN MXyyOEBp NIqxcI5z\WS3Y3XzJGZPNc7|LXnu[JVk\WRiY3XscEBv\XW{b4TvfIlkcXS7 M{GwcFIxQDh6NEG2
MDA-MB-231 MoTlS5Jwf3SqIFnubIljcXSrb36gRZN{[Xl? NXPsZ2pRPzJiaB?= MXfJR|Ux97zgMUCwJO69VQ>? MWeyNFA4OjZ3Mh?=
SK-BR-3 M3f2UGdzd3e2aDDJcohq[mm2aX;uJGF{e2G7 MU[3NkBp MlvYTWM2OO,:nkGwNEDPxE1? MoPhNlAxPzJ4NUK=
PANC-1 M2DDVGdzd3e2aDDJcohq[mm2aX;uJGF{e2G7 MmTHO|IhcA>? M33mXWlEPTExvK6xNFAh|ryP NFrHWmkzODB5Mk[1Ni=>
HPAC MkPWS5Jwf3SqIFnubIljcXSrb36gRZN{[Xl? M3\tW|czKGh? NGK5V2pKSzVy78{eNVAxKM7:TR?= MlTmNlAxPzJ4NUK=
U87 NH\OdYVIem:5dHigTY5pcWKrdHnvckBCe3OjeR?= NFHXPGI4OiCq NUDYOXdjUUN3ME21OU4yKM7:TR?= MUeyNFA4OjZ3Mh?=
U373  MkTtS5Jwf3SqIFnubIljcXSrb36gRZN{[Xl? MUi3NkBp M4G4dGlEPTB;NUKuOUDPxE1? MXuyNFA4OjZ3Mh?=

... Click to View More Cell Line Experimental Data

In vivo S3I-201 (5 mg/kg, i.v. every 2 or every 3 days) shows the antitumor efficacy in mouse models with human breast tumor xenografts that harbor constitutively active Stat3. [1] S3I-201 treatment reduces Varicella-zoster virus (VZV) replication on the basis of the bioluminescence signal and the number of positive skin xenografts compared with DMSO-treated mice by inhibiting STAT3 phosphorylation. [4]


Kinase Assay:[1]
+ Expand

In vitro Stat3 DNA-binding assay and EMSA analysis :

Briefly, 100 mL of biotinyl-e-Ac-EPQpYEEIEL-OH (in 50 mM Tris/150 mM NaCl, pH 7.5) is added to each well of streptavidin-coated 96-well microtiter plates and incubated with shaking at 4 °C overnight. Then plates are rinsed with PBS/Tween 20 and then two times with 200 mL of BSA-T-PBS (0.2% BSA/0.1% Tween 20/PBS). Then 50 mL of Lck-SH2-GST fusion protein (6.4 ng/ml in BSA-T-PBS) is added to each well of the 96-well plate in the presence and absence of 50 mL of S3I-201 (for 30 and 100 mM final concentrations), and the plate is shaken at room temperature for 4 hours. After solutions are removed, each well is rinsed four times with BSA-T-PBS (200 mL), and 100 mL of polyclonal rabbit anti-GST antibody (100 ng/mL in BSA-T-PBS) is added to each well and incubated at 4 °C overnight. After washing with BSA-T-PBS, 100 mL of 200 ng/mL BSA-T-PBS horseradish peroxidase-conjugated mouse anti-rabbit antibody is added to each well and incubated for 45 minutes at room temperature. After four washing steps with BSA-T-PBS and three washing steps with PBS-T, 100 mL of peroxidase substrate is added to each well and incubated for 5-15 minutes. The peroxidase reaction is stopped by adding 100 mL of 1 M sulfuric acid solution, and absorbance is read at 450 nm with an ELISA plate rea
Cell Research:[2]
+ Expand
  • Cell lines: MDA-MB-435, MDA-MB-453 and MDA-MB-231 cells lines
  • Concentrations: ~ 250 μM
  • Incubation Time: 72 hours
  • Method: The MTT assay is based on the conversion of the yellow tetrazolium salt MTT to purple formazan crystals by metabolically active cells. The MTT assay provides a quantitative determination of viable cells. Cells are seeded in 96-well microplates in complete culture medium in the absence or presence of increasing serial dosages of S3I-201 as indicated. At 72 hours after culture, the number of viable cells is measured by adding 100 μL/well of 2 mg/mL MTT solution. After 2 hours, the medium is removed, and the formazan crystals are dissolved by adding 100 μL dimethylsulfoxide per well. The absorbance is read at 590 nm with an enzyme-linked immunosorbent assay reader. Each treatment point is performed in 10 wells or sextuplicate.
    (Only for Reference)
Animal Research:[1]
+ Expand
  • Animal Models: Human breast cancer MDA-MB-231 cells are injected s.c. into the left flank of athymic nu/nu mice.
  • Formulation: S3I-201 is formulated in DMSO.
  • Dosages: ≤5 mg/kg
  • Administration: Administered via i.v.
    (Only for Reference)

Solubility (25°C)

In vitro DMSO 73 mg/mL (199.8 mM)
Water <1 mg/mL
Ethanol <1 mg/mL
In vivo 5% DMSO+corn oil 6mg/mL

* 1 mg/ml means slightly soluble or insoluble.
* Please note that Selleck tests the solubility of all compounds in-house, and the actual solubility may differ slightly from published values. This is normal and is due to slight batch-to-batch variations.

Chemical Information

Molecular Weight 365.36


CAS No. 501919-59-1
Storage powder
in solvent
Synonyms NSC 74859

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Cell Lines Assay Type Concentration Incubation Time Formulation Activity Description PMID