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STAT3 inhibitor 8q   Click here for help

GtoPdb Ligand ID: 10139

Compound class: Synthetic organic
Comment: Compound 8q is reported as an orally active inhibitor of the transcription factor STAT3 [4]. Structurally 8q is a derivative of napabucasin (BBI608), a cancer cell stemness inhibitor that targets the STAT3 pathway [1], and which was evaluated for antineoplastic potential in clinical trial [2]. STAT3 is a crucial component of the JAK/STAT signalling pathway, that is implicated in cancer and inflammation. STAT3 is frequently activated in cancers, where it downmodulates intrinsic immune surveillance of tumour cells. Phosphorylated (activated) STAT3 (pSTAT3) is a marker of poor cancer prognosis [5-6]. Inhibition of the STA3 pathway induces T cell- and NK cell-dependent growth inhibition of tumours and by this mechanism, enhances antitumour immunity [3]. Selective STAT3 inhibitors are being investigated as anti-cancer immunotherapeutics and as more general immunomodulators for non-cancer inflammatory disorders.
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Ligand Activity Visualisation Charts

These are box plot that provide a unique visualisation, summarising all the activity data for a ligand taken from ChEMBL and GtoPdb across multiple targets and species. Click on a plot to see the median, interquartile range, low and high data points. A value of zero indicates that no data are available. A separate chart is created for each target, and where possible the algorithm tries to merge ChEMBL and GtoPdb targets by matching them on name and UniProt accession, for each available species. However, please note that inconsistency in naming of targets may lead to data for the same target being reported across multiple charts.

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View interactive charts of activity data across species
2D Structure
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2D Structure

An image of the ligand's 2D structure. For small molecules with SMILES these are drawn using the NCI/CADD Chemical Identifier Resolver. Click on the image to access the chemical structure search tool with the ligand pre-loaded in the structure editor. For other types of ligands, e.g. longer nucleotides and peptides, a manually drawn representation of the molecule may be provided.

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Physico-chemical Properties
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Physico-chemical Properties

Calculated molecular properties are available for small molecules and natural products (not peptides). Properties were generated using the Chemistry Development Kit (CDK) (Willighagen EL et al. Journal of Cheminformatics vol. 9:33. 2017, doi:10.1186/s13321-017-0220-4; https://cdk.github.io/). All properties were selected to enable the prediction of the Lipinski Rule-of-Five profile or ‘druglikeness’ for each ligand. For more info on each category see the help pages.

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Hydrogen bond acceptors 5
Hydrogen bond donors 1
Rotatable bonds 5
Topological polar surface area 79.62
Molecular weight 352.14
XLogP 2.17
No. Lipinski's rules broken 0

Generated using the Chemistry Development Kit (CDK) (Willighagen EL et al. Journal of Cheminformatics vol. 9:33. 2017, doi:10.1186/s13321-017-0220-4; https://cdk.github.io/)
SMILES / InChI / InChIKey
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SMILES / InChI / InChIKey

SMILES (Simplified Molecular Input Line Entry Specification) A specification for unambiguously describing the structure of chemical molecules using short ASCII strings. Canonical SMILES specify a unique representation of the 2D structure without chiral or isotopic specifications. Isomeric SMILES include chiral specification and isotopes.

Standard InChI (IUPAC International Chemical Identifier) and InChIKey InChI is a non-proprietary, standard, textual identifier for chemical substances designed to facilitate linking of information and database searching. An InChIKey is a simplified version of a full InChI, designed for easier web searching.

Generated using the Chemistry Development Kit (CDK) (Willighagen EL et al. Journal of Cheminformatics vol. 9:33. 2017, doi:10.1186/s13321-017-0220-4; https://cdk.github.io/)

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Canonical SMILES O=C(c1cc2c(o1)C(=O)c1c(C2=O)cccc1)NCCN1CCCCC1
Isomeric SMILES O=C(c1cc2c(o1)C(=O)c1c(C2=O)cccc1)NCCN1CCCCC1
InChI InChI=1S/C20H20N2O4/c23-17-13-6-2-3-7-14(13)18(24)19-15(17)12-16(26-19)20(25)21-8-11-22-9-4-1-5-10-22/h2-3,6-7,12H,1,4-5,8-11H2,(H,21,25)
InChI Key MLNGLWWCXHUBMT-UHFFFAOYSA-N

Generated using the Chemistry Development Kit (CDK) (Willighagen EL et al. Journal of Cheminformatics vol. 9:33. 2017, doi:10.1186/s13321-017-0220-4; https://cdk.github.io/)
References
1. Hubbard JM, Grothey A. (2017)
Napabucasin: An Update on the First-in-Class Cancer Stemness Inhibitor.
Drugs, 77 (10): 1091-1103. [PMID:28573435]
2. Jonker DJ, Nott L, Yoshino T, Gill S, Shapiro J, Ohtsu A, Zalcberg J, Vickers MM, Wei AC, Gao Y et al.. (2018)
Napabucasin versus placebo in refractory advanced colorectal cancer: a randomised phase 3 trial.
Lancet Gastroenterol Hepatol, 3 (4): 263-270. [PMID:29397354]
3. Kortylewski M, Kujawski M, Wang T, Wei S, Zhang S, Pilon-Thomas S, Niu G, Kay H, Mulé J, Kerr WG et al.. (2005)
Inhibiting Stat3 signaling in the hematopoietic system elicits multicomponent antitumor immunity.
Nat Med, 11 (12): 1314-21. [PMID:16288283]
4. Li C, Chen C, An Q, Yang T, Sang Z, Yang Y, Ju Y, Tong A, Luo Y. (2019)
A novel series of napabucasin derivatives as orally active inhibitors of signal transducer and activator of transcription 3 (STAT3).
Eur J Med Chem, 162: 543-554. DOI: 10.1016/j.ejmech.2018.10.067 [PMID:30472602]
5. Yu H, Lee H, Herrmann A, Buettner R, Jove R. (2014)
Revisiting STAT3 signalling in cancer: new and unexpected biological functions.
Nat Rev Cancer, 14 (11): 736-46. [PMID:25342631]
6. Yuan J, Zhang F, Niu R. (2015)
Multiple regulation pathways and pivotal biological functions of STAT3 in cancer.
Sci Rep, 5: 17663. [PMID:26631279]