Currie KS et al. (MAY 2014)
Journal of medicinal chemistry 57 9 3856--73
Discovery of GS-9973, a selective and orally efficacious inhibitor of spleen tyrosine kinase.
Spleen tyrosine kinase (Syk) is an attractive drug target in autoimmune,inflammatory,and oncology disease indications. The most advanced Syk inhibitor,R406,1 (or its prodrug form fostamatinib,2),has shown efficacy in multiple therapeutic indications,but its clinical progress has been hampered by dose-limiting adverse effects that have been attributed,at least in part,to the off-target activities of 1. It is expected that a more selective Syk inhibitor would provide a greater therapeutic window. Herein we report the discovery and optimization of a novel series of imidazo[1,2-a]pyrazine Syk inhibitors. This work culminated in the identification of GS-9973,68,a highly selective and orally efficacious Syk inhibitor which is currently undergoing clinical evaluation for autoimmune and oncology indications.
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Lombardo LJ et al. ( 2004)
Journal of medicinal chemistry 47 27 6658--6661
Discovery of N-(2-chloro-6-methyl- phenyl)-2-(6-(4-(2-hydroxyethyl)- piperazin-1-yl)-2-methylpyrimidin-4- ylamino)thiazole-5-carboxamide (BMS-354825), a dual Src/Abl kinase inhibitor with potent antitumor activity in preclinical assays.
A series of substituted 2-(aminopyridyl)- and 2-(aminopyrimidinyl)thiazole-5-carboxamides was identified as potent Src/Abl kinase inhibitors with excellent antiproliferative activity against hematological and solid tumor cell lines. Compound 13 was orally active in a K562 xenograft model of chronic myelogenous leukemia (CML),demonstrating complete tumor regressions and low toxicity at multiple dose levels. On the basis of its robust in vivo activity and favorable pharmacokinetic profile,13 was selected for additional characterization for oncology indications.
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Y. Hirata et al. (Sep 2025)
Scientific Reports 15
Discovery of novel disulfide-containing PD-1/PD-L1 inhibitor with in vivo influenza therapeutic efficacy
Monoclonal antibody-based immune checkpoint inhibitors,which have brought breakthrough effects in cancer treatments,are expected to assist in the treatment of viral diseases. However,antibody therapies may cause immune-related side effects,such as inflammation and pneumonia,due to cytokine storms. Small-molecule PD-1/PD-L1 inhibitors are an alternative to monoclonal antibody-based therapeutics. We have identified a novel small-molecule PD-1/PD-L1 inhibitor having a functional group (disulfide group),namely compound 2 (molecular weight: 456.6),from our library of sulfur-containing protein–protein interaction inhibitor compounds. Compound 2 selectively bound to PD-L1 over PD-1,with the dissociation rate constant (K D ) of 77.60 ± 4.44 nM (obtained by affinity analysis) and showed promising T cell activation recovery. A molecular docking simulation study between 2 and PD-L1 suggested that 2 binds to PD-L1 in a binding mode different from those of other small-molecule PD-L1/PD-1 inhibitors. Notably,oral administration of 2 to mice pre-infected with influenza A virus (A/NWS/33,H1N1 subtype) caused a significant increase in the neutralizing antibody titers,as well as recovery from influenza-induced pneumonia. Overall,2 provides insight for the development of therapeutic drugs against early viral infections,with both virus titer-reducing and antibody titer-boosting effects. Moreover,2 is widely used as a rubber peptizing agent in the production process of tires and other rubber products. Our findings may provide useful information for investigating its influence on living organisms. The online version contains supplementary material available at 10.1038/s41598-025-17982-3. Subject terms: Drug discovery and development,Pharmacology,Screening,Structure-based drug design
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M. A. Berrocal-Rubio et al. (Aug 2024)
BMC Genomics 25 Suppl 1
Discovery of NRG1-VII: the myeloid-derived class of NRG1
The growth factor Neuregulin-1 (NRG1) has pleiotropic roles in proliferation and differentiation of the stem cell niche in different tissues. It has been implicated in gut,brain and muscle development and repair. Six isoform classes of NRG1 and over 28 protein isoforms have been previously described. Here we report a new class of NRG1,designated NRG1-VII to denote that these NRG1 isoforms arise from a myeloid-specific transcriptional start site (TSS) previously uncharacterized. Long-read sequencing was used to identify eight high-confidence NRG1-VII transcripts. These transcripts presented major structural differences from one another,through the use of cassette exons and alternative stop codons. Expression of NRG1-VII was confirmed in primary human monocytes and tissue resident macrophages and induced pluripotent stem cell-derived macrophages (iPSC-derived macrophages). Isoform switching via cassette exon usage and alternate polyadenylation was apparent during monocyte maturation and macrophage differentiation. NRG1-VII is the major class expressed by the myeloid lineage,including tissue-resident macrophages. Analysis of public gene expression data indicates that monocytes and macrophages are a primary source of NRG1. The size and structure of class VII isoforms suggests that they may be more diffusible through tissues than other NRG1 classes. However,the specific roles of class VII variants in tissue homeostasis and repair have not yet been determined. The online version contains supplementary material available at 10.1186/s12864-024-10723-2.
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Z. Dai et al. (sep 2022)
Phytomedicine : international journal of phytotherapy and phytopharmacology 104 154335
Discovery of potent immune-modulating molecule taccaoside A against cancers from structures-active relationships of natural steroidal saponins.
BACKGROUND In recent years,the T-cell therapy and immune checkpoint inhibitors toward CTLA-4 and PD-1/PD-L1 axis antibody therapy have acquired encouraging success. However,most of patients were still not benefited with lots of troubles,such as low penetration of tissues/cells,strong immunogenicity and cytokine release syndrome,and long manufacturing process and expensive costs. By contrast,the immune-modulating small molecules possessed natural advantages to overcome these obstacles and might achieve greater success. PURPOSE Exploring the potent immune-modulating natural small molecules and revealing what kinds of molecules or structures with the immunomodulatory activity against cancers. METHODS A novel non-cytotoxic T-cell immunomodulating screening model was used to identify the cytotoxic/selective/immunomodulatory bioactivity for 148 natural steroidal saponins. The structure-activity relationships (SARs) research was used to reveal the key groups for immunomodulation/cytotoxicity/selectivity. The negative selection was used to isolate and purify the T-cell. The cell viability assay was used to measure the anti-cancer effect in vitro. The ELISA assay was used to detect the cytokines for IL-1$\beta$,IL-6,TNF-$\alpha$,IFN-$\gamma$,IL-12,perforin and granzyme B (GZMB). The western blotting assay was used to research the immunomodulatory mechanism. The siRNA knockdown was used to generate the IFN-$\gamma$ resistant melanoma cells. The NOG immune-deficient mice were used to evaluate the anti-tumor efficacy in vivo. The peripheral blood samples from 10 cancer patients were used to detect the broad population anti-tumor efficacy. RESULTS It was reported that the correlation among structures and immunomodulation/ cytotoxicity/selectivity,in which opening ring-F with 26-O-glucopyranosyl,disaccharide and trisaccharide chains at C-3,steric hindrance and polarity of C-22 were key immunomodulatory groups. Moreover,taccaoside A was identified as the most potent candidate against cancer cells,including non-small cell lung cancer,triple negative breast cancer,and the IFN-$\gamma$ resistant melanoma,partly through enhancing T lymphocyte mTORC1-Blimp-1 signal to secrete GZMB. Besides,10 patients derived T-cell also would be modulated against cancer cells in vitro. Moreover,the overall survival was great extended (>140 days vs 93 days) with nearly 100% tumor burden disappearance (0 mm3vs 1006 ± 79.5 mm3) in mice. CONCLUSION This work demonstrated one possibility for this concerned purpose,and identified a potent immune-modulating natural molecule taccaoside A,which might contribute to cancer immunotherapy in future.
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Tobe M et al. ( 2003)
Bioorganic & medicinal chemistry 11 3 383--391
Discovery of quinazolines as a novel structural class of potent inhibitors of NF-kappa B activation.
We disclose here a new structural class of low-molecular-weight inhibitors of NF-kappa B activation that were designed and synthesized by starting from quinazoline derivative 6a. Structure-activity relationship (SAR) studies based on 6a elucidated the structural requirements essential for the inhibitory activity toward NF-kappa B transcriptional activation,and led to the identification of the 6-amino-4-phenethylaminoquinazoline skeleton as the basic framework. In this series of compounds,11q,containing the 4-phenoxyphenethyl moiety at the C(4)-position,showed strong inhibitory effects on both NF-kappa B transcriptional activation and TNF-alpha production. Furthermore,11q exhibited an anti-inflammatory effect on carrageenin-induced paw edema in rats.
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Hideshima T et al. (OCT 2016)
Proceedings of the National Academy of Sciences of the United States of America
Discovery of selective small-molecule HDAC6 inhibitor for overcoming proteasome inhibitor resistance in multiple myeloma.
Multiple myeloma (MM) has proven clinically susceptible to modulation of pathways of protein homeostasis. Blockade of proteasomal degradation of polyubiquitinated misfolded proteins by the proteasome inhibitor bortezomib (BTZ) achieves responses and prolongs survival in MM,but long-term treatment with BTZ leads to drug-resistant relapse in most patients. In a proof-of-concept study,we previously demonstrated that blocking aggresomal breakdown of polyubiquitinated misfolded proteins with the histone deacetylase 6 (HDAC6) inhibitor tubacin enhances BTZ-induced cytotoxicity in MM cells in vitro. However,these foundational studies were limited by the pharmacologic liabilities of tubacin as a chemical probe with only in vitro utility. Emerging from a focused library synthesis,a potent,selective,and bioavailable HDAC6 inhibitor,WT161,was created to study the mechanism of action of HDAC6 inhibition in MM alone and in combination with BTZ. WT161 in combination with BTZ triggers significant accumulation of polyubiquitinated proteins and cell stress,followed by caspase activation and apoptosis. More importantly,this combination treatment was effective in BTZ-resistant cells and in the presence of bone marrow stromal cells,which have been shown to mediate MM cell drug resistance. The activity of WT161 was confirmed in our human MM cell xenograft mouse model and established the framework for clinical trials of the combination treatment to improve patient outcomes in MM.
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Chigaev A et al. (FEB 2011)
The Journal of biological chemistry 286 7 5455--63
Discovery of very late antigen-4 (VLA-4, alpha4beta1 integrin) allosteric antagonists.
Integrins are cell adhesion receptors that mediate cell-to-cell,or cell-to-extracellular matrix adhesion. They represent an attractive target for treatment of multiple diseases. Two classes of small molecule integrin inhibitors have been developed. Competitive antagonists bind directly to the integrin ligand binding pocket and thus disrupt the ligand-receptor interaction. Allosteric antagonists have been developed primarily for α(L)β(2)- integrin (LFA-1,lymphocyte function-associated antigen-1). Here we present the results of screening the Prestwick Chemical Library using a recently developed assay for the detection of α(4)β(1)-integrin allosteric antagonists. Secondary assays confirmed that the compounds identified: 1) do not behave like competitive (direct) antagonists; 2) decrease ligand binding affinity for VLA-4 ∼2 orders of magnitude; 3) exhibit antagonistic properties at low temperature. In a cell based adhesion assay in vitro,the compounds rapidly disrupted cellular aggregates. In accord with reports that VLA-4 antagonists in vivo induce mobilization of hematopoietic progenitors into the peripheral blood,we found that administration of one of the compounds significantly increased the number of colony-forming units in mice. This effect was comparable to AMD3100,a well known progenitor mobilizing agent. Because all the identified compounds are structurally related,previously used,or currently marketed drugs,this result opens a range of therapeutic possibilities for VLA-4-related pathologies.
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A. Rodríguez-Martínez et al. (Apr 2025)
Scientific Reports 15
Discovery of Z1362873773: a novel fascin inhibitor from a large chemical library for colorectal cancer
Metastasis is one of the leading causes of cancer-related death worldwide. Fascin,a protein that bundles actin filaments to produce protrusions in cancer cells,plays a significant role in the enhancement of cell migration. This protein has been shown that the overexpression of this protein is related to the appearance of different types of cancer,such as colorectal cancer. In this study,we conducted in silico screening of the Enamine library,a compound library with a broad chemical space. Using a ligand-based virtual screening approach based on the pharmacophore model of G2,we identified the predicted inhibitors. First,these compounds were validated by physicochemical analysis. Differential scanning calorimetry (DSF) was used to study the binding between the predicted compounds and fascin protein,followed by an F-actin bundling assay to determine which compounds inhibited the bundling function of fascin. Z1362873773,which exhibited binding to fascin and inhibited F-actin bundling,was further tested in cell cultures to assess its effects on cancer cell viability and migration as well as in organoid models to evaluate potential cytotoxicity. Finally,we established a protocol that can be applied to discover anti-fascin agents from diverse compound libraries. A new molecule has been identified with considerable fascin inhibitory and migration-arresting capacity,which may lead to the development of new therapies to treat cancer. The online version contains supplementary material available at 10.1038/s41598-025-96457-x. Subject terms: Biochemistry,Biophysics,Cancer,Drug discovery,Molecular biology,Virtual drug screening
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Gorojankina T et al. ( 2013)
Molecular pharmacology 83 5 1020--1029
Discovery, molecular and pharmacological characterization of GSA-10, a novel small-molecule positive modulator of Smoothened.
Activation of the Smoothened (Smo) receptor mediates Hedgehog (Hh) signaling. Hh inhibitors are in clinical trials for cancer,and small-molecule Smo agonists may have therapeutic interests in regenerative medicine. Here,we have generated and validated a pharmacophoric model for Smo agonists and used this model for the virtual screening of a library of commercially available compounds. Among the 20 top-scoring ligands,we have identified and characterized a novel quinolinecarboxamide derivative,propyl 4-(1-hexyl-4-hydroxy-2-oxo-1,2-dihydroquinoline-3-carboxamido) benzoate,(GSA-10),as a Smo agonist. GSA-10 fits to the agonist pharmacophoric model with two hydrogen bond acceptor groups and four hydrophobic regions. Using pharmacological,biochemical,and molecular approaches,we provide compelling evidence that GSA-10 acts at Smo to promote the differentiation of multipotent mesenchymal progenitor cells into osteoblasts. However,this molecule does not display the hallmarks of reference Smo agonists. Remarkably,GSA-10 does not recognize the classic bodipy-cyclopamine binding site. Its effect on cell differentiation is inhibited by Smo antagonists,such as MRT-83,SANT-1,LDE225,and M25 in the nanomolar range,by GDC-0449 in the micromolar range,but not by cyclopamine and CUR61414. Thus,GSA-10 allows the pharmacological characterization of a novel Smo active site,which is notably not targeted to the primary cilium and strongly potentiated by forskolin and cholera toxin. GSA-10 belongs to a new class of Smo agonists and will be helpful for dissecting Hh mechanism of action,with important implications in physiology and in therapy.
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Liu E et al. (APR 2003)
Blood 101 8 3294--301
Discrimination of polycythemias and thrombocytoses by novel, simple, accurate clonality assays and comparison with PRV-1 expression and BFU-E response to erythropoietin.
Essential thrombocythemia (ET) and polycythemia vera (PV) are clonal myeloproliferative disorders that are often difficult to distinguish from other causes of elevated blood cell counts. Assays that could reliably detect clonal hematopoiesis would therefore be extremely valuable for diagnosis. We previously reported 3 X-chromosome transcription-based clonality assays (TCAs) involving the G6PD,IDS,and MPP1 genes,which together were informative in about 65% of female subjects. To increase our ability to detect clonality,we developed simple TCA for detecting the transcripts of 2 additional X-chromosome genes: Bruton tyrosine kinase (BTK) and 4-and-a-half LIM domain 1 (FHL1). The combination of TCA established the presence or absence of clonal hematopoiesis in about 90% of female subjects. We show that both genes are subject to X-chromosome inactivation and are polymorphic in all major US ethnic groups. The 5 TCAs were used to examine clonality in 46 female patients along with assays for erythropoietin-independent erythroid colonies (EECs) and granulocyte PRV-1 mRNA levels to discriminate polycythemias and thrombocytoses. Of these,all 19 patients with familial polycythemia or thrombocytosis had polyclonal hematopoiesis,whereas 22 of 26 patients with clinical evidence of myeloproliferative disorder and 1 patient with clinically obscure polycythemia were clonal. Interestingly,interferon alpha therapy in 2 patients with PV was associated with reversion of clonal to polyclonal hematopoiesis. EECs were observed in 14 of 14 patients with PV and 4 of 12 with ET,and increased granulocyte PRV-1 mRNA levels were found in 9 of 13 patients with PV and 2 of 12 with ET. Thus,these novel clonality assays are useful in the diagnosis and follow-up of polycythemic conditions and disorders with increased platelet levels.
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Ang Y-S et al. (DEC 2016)
Cell 167 7 1734--1749.e22
Disease Model of GATA4 Mutation Reveals Transcription Factor Cooperativity in Human Cardiogenesis.
Mutation of highly conserved residues in transcription factors may affect protein-protein or protein-DNA interactions,leading to gene network dysregulation and human disease. Human mutations in GATA4,a cardiogenic transcription factor,cause cardiac septal defects and cardiomyopathy. Here,iPS-derived cardiomyocytes from subjects with a heterozygous GATA4-G296S missense mutation showed impaired contractility,calcium handling,and metabolic activity. In human cardiomyocytes,GATA4 broadly co-occupied cardiac enhancers with TBX5,another transcription factor that causes septal defects when mutated. The GATA4-G296S mutation disrupted TBX5 recruitment,particularly to cardiac super-enhancers,concomitant with dysregulation of genes related to the phenotypic abnormalities,including cardiac septation. Conversely,the GATA4-G296S mutation led to failure of GATA4 and TBX5-mediated repression at non-cardiac genes and enhanced open chromatin states at endothelial/endocardial promoters. These results reveal how disease-causing missense mutations can disrupt transcriptional cooperativity,leading to aberrant chromatin states and cellular dysfunction,including those related to morphogenetic defects.
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