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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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
BT474R  MoXYSpVv[3Srb36gRZN{[Xl? MoG0OVAh|ryP MmXtNVAuPjBiZB?= NIrh[G9qdmirYnn0d{BUXEGWMzDhZ5Rqfmm2eR?= NUDINZpvOjV|Mke1OlE>
NCI-N87R NFfpS29HfW6ldHnvckBCe3OjeR?= NVX3[JJpPTBizszN MXyxNE03OCCm NGfHZ49qdmirYnn0d{BUXEGWMzDhZ5Rqfmm2eR?= MVWyOVMzPzV4MR?=
GH3 M2LnO2dzd3e2aDDJcohq[mm2aX;uJGF{e2G7 M2HPXVUxNTF{NTFOwG0> M{fWNlczKGh? MYDheJRmdnWjdHXzJJRp\SClZXzsJIdzd3e2aDDpckBiKGSxc3Wt[IVx\W6mZX70JI1idm6nch?= M2jnNlI2Pzd2NUCz
GC  NFWze2tIem:5dHigTY5pcWKrdHnvckBCe3OjeR?= NV[3PFg6PTBvMUK1JO69VQ>? Mli1O|IhcA>? NYrWe4l6[XS2ZX71ZZRmeyC2aHWgZ4VtdCCpcn;3eIghcW5iYTDkc5NmNWSncHXu[IVvfCCvYX7u[ZI> MUmyOVc4PDVyMx?=
H460  M{XVfmFxd3C2b4Ppd{BCe3OjeR?= MkKzNVAxyqCwTR?= MY[yOOKhcA>? M2PBUolv\HWlZYOgZ4VtdCCjcH;weI9{cXNiY3:teJJm[XSnZDD3bZRpKEKHWkKzOS=> M3fpU|I1PDd{NUO4
A459 NVvadHc4SXCxcITvd4l{KEG|c3H5 NGj2VIEyODEEoH7N MVSyOOKhcA>? NWXVUGRXcW6mdXPld{Bk\WyuIHHwc5B1d3OrczDjc{11emWjdHXkJJdqfGhiQlXaNlM2 NUPENId2OjR2N{K1N|g>
H460  M3j3PWFxd3C2b4Ppd{BCe3OjeR?= NHvyRncyODEEoH7N M2C0NFI1yqCq NIHWVY9mdmijbnPld{Bk\WyuIHTlZZRpKGOxLYTy[YF1\WRid3n0bEBNYTJ7NECwNi=> NVvLWlBCOjR2N{K1N|g>
MT-2 NV30RopoSXCxcITvd4l{KEG|c3H5 M{frS|c2NTNyMDFOwG0> MoLkNlQwPDhiaB?= NYXQWolze3WycILld5NmeyClZXzsJJBzd2yrZnXyZZRqd25iaX6gZUBld3OnLXTldIVv\GWwdDDtZY5v\XJiYX7kJIlv\HWlZYOgZ4VtdCCjcH;weI9{cXQEoB?= MVqyOFA6ODl7NR?=
HUT-102 MVrBdI9xfG:|aYOgRZN{[Xl? NWroZVBXPzVvM{CwJO69VQ>? NEKzWpMzPC92ODDo MVrzeZBxemW|c3XzJINmdGxicILvcIln\XKjdHnvckBqdiCjIHTvd4Uu\GWyZX7k[Y51KG2jbn7ldkBidmRiaX7keYNmeyClZXzsJIFxd3C2b4Ppd:Kh M1vQdlI1ODlyOUm1
U373  NHrEZZpIem:5dHigTY5pcWKrdHnvckBCe3OjeR?= M2riPFEzPSEQvF2= MX:yOEBp M3vwbWROW09? Mmq2[Il{enWydIOgV3RCXDNic3nncoFtcW6pIHHu[EBxem:uaX\ldoF1cW:w M4\mdFI1ODdyOEKw
T-cell  MV\Hdo94fGhiSX7obYJqfGmxbjDBd5NigQ>? NUD1TYRkUUN3ME21NEDPxE1? Mk[4NlQxPjh5M{G=
H1299 NHLyPZRHfW6ldHnvckBCe3OjeR?= MnjUOVAwOTByIN88US=> NEHt[XI1QCCq NFSzUYx{fXCycnXzd4V{KG2rUj25NoEh\XiycnXzd4lwdiCmb4PlMYRmeGWwZHXueIx6 MmHJNlM5OjB{NUS=
H460  MXTGeY5kfGmxbjDBd5NigQ>? NW\rSWpVPTBxMUCwJO69VQ>? NX60dnN1PDhiaB?= MljpbY5pcWKrdIOgeIhmKFO2YYSzR{BqdmO{ZXHz[YQhdWmULUmyZUBmgHC{ZYPzbY9v M{PHVVI{QDJyMkW0
PLC/PRF/5  MojwS5Jwf3SqIFnubIljcXSrb36gRZN{[Xl? MofpNVAxKG6P NGPrOFg1QCCq NIrtTGFFVVOR M1fkNYlvcGmkaYTzJJRp\SCLTD22JJN1cW23bHH0bY9vKHC{b33veIVlKGOnbHygdJJwdGmoZYLheIlwdg>? NIjuZ|EzOzN4NEO4PS=>
Huh7 M4HVbmdzd3e2aDDJcohq[mm2aX;uJGF{e2G7 NX\YNlIyOTByIH7N NXW2NWRbPDhiaB?= NFTXe2dFVVOR NFXhOldqdmirYnn0d{B1cGViSVytOkB{fGmvdXzheIlwdiCycn;tc5Rm\CClZXzsJJBzd2yrZnXyZZRqd25? NV3Q[Xh6OjN|NkSzPFk>
HUVEC  MUXGeY5kfGmxbjDBd5NigQ>? Mmr5NE42NTJyIN88US=> M{TVVVI1KGh? M{Tu[mROW09? NVnHSllke3WycILld5NmeyC2aHWgbJlxd3irYT3pcoR2[2WmIHHjZ5VufWyjdHnvckBw\iCKSV[tNe6y MWKyNVUzOzV3OR?=
 U-373 MG M3X0ZmN6fG:2b4jpZ4l1gSCDc4PhfS=> NXO3NopiOy9zMDFOwG0> MVOyOEBp NXTPR3pxemWmdXPld{BHVi4Qsz3pcoR2[2WmIHPlcIwhdmW3cn;0c5hq[2m2eR?= MnH3NlA5QDh2MU[=
MDA-MB-231 Mke3S5Jwf3SqIFnubIljcXSrb36gRZN{[Xl? Mn;JO|IhcA>? NVTGSI5YUUN3MP-8olExOCEQvF2= NVLCeWhYOjByN{K2OVI>
SK-BR-3 NGrscZBIem:5dHigTY5pcWKrdHnvckBCe3OjeR?= M3yxTlczKGh? M2HremlEPTExvK6xNFAh|ryP M3jxelIxODd{NkWy
PANC-1 MlnWS5Jwf3SqIFnubIljcXSrb36gRZN{[Xl? MmWxO|IhcA>? MmLKTWM2OO,:nkGwNEDPxE1? MVuyNFA4OjZ3Mh?=
HPAC MlXnS5Jwf3SqIFnubIljcXSrb36gRZN{[Xl? NV7YVWdxPzJiaB?= M4PVcmlEPTExvK6xNFAh|ryP NVnIb3B7OjByN{K2OVI>
U87 MnuzS5Jwf3SqIFnubIljcXSrb36gRZN{[Xl? M{\qV|czKGh? MXzJR|UxRTV3LkGg{txO NUfrcnFzOjByN{K2OVI>
U373  NIDseJZIem:5dHigTY5pcWKrdHnvckBCe3OjeR?= NFPxe444OiCq NGrXcoRKSzVyPUWyMlUh|ryP M1nBeVIxODd{NkWy

... 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]
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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 Insoluble
Ethanol Insoluble
In vivo Add solvents to the product individually and in order(Data is from Selleck tests instead of citations):
5% DMSO+corn oil
For best results, use promptly after mixing.

* 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