small molecule inhibitors  (Tocris)

Journal: Journal of Virology

Article Title: Potent in vitro synergistic antiviral effects of the pan-coronavirus fusion inhibitor EK1 in combination with RBD-specific antibodies or M pro inhibitors

doi: 10.1128/jvi.00076-26

Figure Lengend Snippet: Cytotoxicity of EK1, antibodies, and M pro inhibitors on Caco-2 and RD cells. ( A–G ) Cytotoxicity of EK1, PF-07321332, RAY1216, S-217622, G7, bn03, and control on Caco-2 cells. ( H–L ) Cytotoxicity of EK1, PF-07321332, RAY1216, S-217622, and control on RD cells. Data represent mean ± SD from three independent experiments ( n = 3).

Article Snippet: The small-molecule M pro inhibitors nirmatrelvir (PF-07321332), RAY1216, and ensitrelvir (S-217622) were purchased from MedChemExpress (Shanghai, China).

Techniques: Control

Journal: Journal of Virology

Article Title: Potent in vitro synergistic antiviral effects of the pan-coronavirus fusion inhibitor EK1 in combination with RBD-specific antibodies or M pro inhibitors

doi: 10.1128/jvi.00076-26

Figure Lengend Snippet: Synergistic inhibition of authentic SARS-CoV-2 BA.2 and HCoV-OC43 by dual antiviral combinations. ( A ) Crystal structure of the M pro active site (PDB ID: 7CAM ). The protease is shown as a semi-transparent surface in gray, with the inhibitor-binding cleft highlighted in green. ( B ) Binding sites of M pro with PF-07321332 (PDB ID: 7VH8) in green, RAY1216 (PDB ID: 8IGN ) in yellow, and S-217622 (PDB ID: 8HEF ) in orange. ( C–H ) Dose-response analyses of the fusion inhibitor EK1 in combination with three distinct M pro inhibitors against authentic SARS-CoV-2 BA.2 ( C–E ) and HCoV-OC43 ( F–H ). In each panel, EK1 and the respective M pro inhibitor were tested both individually and as fixed-ratio combinations (molar ratios: PF-07321332, 20:3 for BA.2 and 25:4 for OC43; RAY1216, 4:1 for BA.2 and 25:1 for OC43; S-217622, 4:1 for BA.2 and 25:1 for OC43). Viral inhibition was quantified by fluorescent plaque assay (BA.2), and cell viability was assessed using the cell counting kit-8 (CCK-8) assay (OC43) at 48 h post-infection. Data represent mean ± SD from three independent experiments ( n = 3).

Article Snippet: The small-molecule M pro inhibitors nirmatrelvir (PF-07321332), RAY1216, and ensitrelvir (S-217622) were purchased from MedChemExpress (Shanghai, China).

Techniques: Inhibition, Binding Assay, Plaque Assay, Cell Counting, CCK-8 Assay, Infection

Journal: Journal of Virology

Article Title: Potent in vitro synergistic antiviral effects of the pan-coronavirus fusion inhibitor EK1 in combination with RBD-specific antibodies or M pro inhibitors

doi: 10.1128/jvi.00076-26

Figure Lengend Snippet: Conceptual framework for combinatorial antiviral trident therapy. Schematic overview illustrating the underlying rationale and mechanistic logic of multi-agent intervention against coronavirus infection. By simultaneously targeting discrete stages of the viral life cycle, including membrane fusion (EK1, PDB ID: 7C53 ), receptor engagement (neutralizing antibodies G7 (PDB ID: 8YWE) and nanobodies bn03 (PDB ID: 7WHJ) against RBD), and viral replication (M pro inhibitors: PF-07321332 [PDB ID: 7VH8 ]; RAY1216 [PDB ID: 8IGN ]; S-217622 [PDB ID: 8HEF ]), this approach achieves potent, synergistic inhibition of viral entry, genome replication, and progeny virion production. Dual- or triple-agent combinations permit dose reduction of individual compounds, thereby minimizing toxicity and cost, while curtailing the emergence of resistant variants through multifaceted blockade. Trident therapy defines a modular platform for rapid deployment of broad-spectrum antivirals against SARS-CoV-2 and future zoonotic coronaviruses.

Article Snippet: The small-molecule M pro inhibitors nirmatrelvir (PF-07321332), RAY1216, and ensitrelvir (S-217622) were purchased from MedChemExpress (Shanghai, China).

Techniques: Infection, Membrane, Inhibition

Journal: Frontiers in Immunology

Article Title: Identifying the therapeutic potential of niclosamide in overcoming IFN-gamma dependent cancer immune evasion in the tumor microenvironment

doi: 10.3389/fimmu.2026.1761715

Figure Lengend Snippet: IFNγ up-regulate PD-L1 expression in MC38 cells through IFN-STAT1 signaling. PD-L1 expression on MC38 cell surface was significantly increased in the presence of IFN-γ analyzed by flow cytometry (A) and by immune fluorescent staining (B-C) at 24 hours. (D) When treated with siRNA of STAT1, the up-regulation of PD-L1 was significantly reduced, while siRNA of STAT3 has an opposite effect. (E, F) The small interfering RNA reaches a sufficient knock down of STAT1 and STAT3, as shown by real-time PCR assay. (G-I) The mRNA of STAT1 target genes such as CXCL10 and IL-15 shown similar trend of regulation by IFN-γ as PD-L1. (J) The mRNA of STAT3 target gene, MCL-1, shown totally different regulation under normal condition and under treatment of siRNAs. (K, L) The expression of STAT1/STAT3 normal and phosphorylated proteins, and PD-L1 proteins in MC38 cell lines were measured by Western blotting with different dose of IFN-γ stimulation (K) or after knocking down of STAT1 (siSTAT1) or STAT3 (siSTAT3) (L ). The number on the image indicates the relative abundance of PD-L1 protein (fold of control). The results are expressed as the mean ± SEM of triplicate measurements in each group. *p<0.05, **p<0.01, ***p<0.001.

Article Snippet: We evaluated small molecule STAT1 inhibitor Fludarabine (F-ara-A, NSC 118218) (MedChemExpress, Cat. No.: HY-B0069) and STAT3 inhibitor Niclosamide (BAY2353, MedChemExpress, Cat. No.: HY-B0497).

Techniques: Expressing, Flow Cytometry, Staining, Small Interfering RNA, Knockdown, Real-time Polymerase Chain Reaction, Western Blot, Control

Journal: Frontiers in Immunology

Article Title: Identifying the therapeutic potential of niclosamide in overcoming IFN-gamma dependent cancer immune evasion in the tumor microenvironment

doi: 10.3389/fimmu.2026.1761715

Figure Lengend Snippet: IFN-γ modulate cancer cell stemness in MC38 cells indirectly through IFN-STAT3 pathway. (A-C) Ki-67 expression in the MC38 tumor spheres was significantly reduced in the presence of IFN-γ analyzed by flow cytometry and immune fluorescence. (D, E) The tumor sphere forming unit induced in the MC38 cells were also reduced in the presence of IFN-γ (Arrowhead: tumor spheroid. Scale bar: 200μm). (F) When MC38 cells were pre-treated with siRNA of STAT1/STAT3, the SFU show different changes. (G) When MC38 cells were pre-treated with siRNA of STAT1/STAT3, both the CD44 hi CD133- and CD44 hi CD133+ cell population show different trend of regulation by IFN-γ. (H-K) The mRNA of cancer stem cell markers was measured by real-time PCR. (L) The expression of cancer stem cell marker proteins in cell nucleus was measured by Western blot. The results are expressed as the mean ± SEM of triplicate measurements in each group. *p<0.05, **p<0.01, nd, no significant difference.

Article Snippet: We evaluated small molecule STAT1 inhibitor Fludarabine (F-ara-A, NSC 118218) (MedChemExpress, Cat. No.: HY-B0069) and STAT3 inhibitor Niclosamide (BAY2353, MedChemExpress, Cat. No.: HY-B0497).

Techniques: Expressing, Flow Cytometry, Fluorescence, Real-time Polymerase Chain Reaction, Marker, Western Blot

Journal: Frontiers in Immunology

Article Title: Identifying the therapeutic potential of niclosamide in overcoming IFN-gamma dependent cancer immune evasion in the tumor microenvironment

doi: 10.3389/fimmu.2026.1761715

Figure Lengend Snippet: Niclosamide has inhibition effect on both STAT1 and STAT3, which blocks IFN-γ-induced PD-L1 up-regulation in MC38 cells while also reduces CSCs formation. (A) The expression of STAT1/STAT3 signaling pathway and PD-L1 proteins in MC38 cell lines with Fludarabine and Niclosamide treatment was measured by Western blot. (B) The surface PDL1 expression level was measured by FACS with IFN-γ and Niclosamide treatment. (C) The cell viability of MC38 when co-cultured with T cells and pre-treated with Fludarabine (F-ara-A) or Niclosamide were measured by CCK8 assay. (D) The sphere forming units induced in MC38 cells was measured with or without Niclosamide treatment. (E) The cell population of CD44 hi CD133+ in MC38 treated with Niclosamide was measured by FACS. (F) The expression of cancer stem cell marker proteins in cell nucleus was measured by Western blot. The results are expressed as the mean ± SEM of triplicate measurements in each group. *p<0.05, **p<0.01, ***p<0.001.

Article Snippet: We evaluated small molecule STAT1 inhibitor Fludarabine (F-ara-A, NSC 118218) (MedChemExpress, Cat. No.: HY-B0069) and STAT3 inhibitor Niclosamide (BAY2353, MedChemExpress, Cat. No.: HY-B0497).

Techniques: Inhibition, Expressing, Western Blot, Cell Culture, CCK-8 Assay, Marker

Journal: Frontiers in Immunology

Article Title: Identifying the therapeutic potential of niclosamide in overcoming IFN-gamma dependent cancer immune evasion in the tumor microenvironment

doi: 10.3389/fimmu.2026.1761715

Figure Lengend Snippet: Hypoxia enhances PD-L1 upregulation by IFN-γ, while Niclosamide down-regulates Hif1α under hypoxic conditions. (A, B) The expression level of STAT1/STAT3 signaling pathway and PD-L1 proteins in MC38 cell lines with siRNA (A) or Fludarabine and Niclosamide treatment (B) was measured by Western blot. (C) Cell viability of MC38 cells pre-treated with different dose of IFN-γ and co-cultured with primary T cells were measured by CCK8 assay, under normoxia or hypoxic conditions. (D) The Cell viability of MC38 cells treated with different dose of Fludarabine or Niclosamide were measured by CCK8 assay, under normoxia or hypoxic conditions. The results are expressed as the mean ± SEM of triplicate measurements in each group. *p<0.05, **p<0.01, ***p<0.001.

Article Snippet: We evaluated small molecule STAT1 inhibitor Fludarabine (F-ara-A, NSC 118218) (MedChemExpress, Cat. No.: HY-B0069) and STAT3 inhibitor Niclosamide (BAY2353, MedChemExpress, Cat. No.: HY-B0497).

Techniques: Expressing, Western Blot, Cell Culture, CCK-8 Assay

Journal: Nature Communications

Article Title: Brachiopod genome unveils the evolution of BMP signalling in bilaterian body patterning

doi: 10.1038/s41467-026-70403-5

Figure Lengend Snippet: a Developmental timeline of L. anatina (hours post-fertilisation, hpf) and BMP manipulation windows. Embryos were treated with inhibitors (LDN-193189 and K02288 ) or recombinant BMP4. EB early blastula, B blastula, EG early gastrula, MG mid-gastrula, LG late gastrula, EL early larva, 1PCL one-pair-cirri larva, 1PCL is rotated 90° relative to EL. b Body axes and gastrulation movements. bp blastopore, tn tentacle, mo mouth, ml mantle lobe. pSmad1/5 (red) marks the BMP gradient; mitotic cells (pHistone H3) are shown as red circles; embryonic shells (chitin) are green. c – f Immunostaining of pSmad1/5 antibody (red) in optical sectioned late gastrulae. High-dose treatments are shown unless noted. BMP inhibitor treatment disrupted gastrulation with K02288 causing a more severe phenotype. Nuclei are labelled with Hoechst 33342 (blue). Cytosol is counterstained with CellMask deep red (grey). Nuclearized pSmad1/5 signals are marked by arrowheads and empty arrowheads in blastodermal and ingressed mesenchymal cells, respectively. Scale bar, 50 μm. g – j Immunostaining of pHistone H3 antibody (red). Mitotic cells are indicated by arrows. k – n Staining of chitin with a chitin-binding probe (green). Chitin staining marks the embryonic shells. The arrowhead marks the dorsal edge of the larva, which lacks chitin staining in the control ( k ). Larvae are shown in lateral view ( k , l ), with a slight rotation in ( n ) to bring the ventral side partially into view. o Statistics of cell proliferation under BMP signalling perturbation ( n = 4–5 embryos). High dose (LDN-193189, 8 μM; K02288 , 500 nM; mBMP4, 200 ng/mL); low dose (LDN-193189, 4 μM; K02288 , 250 nM; mBMP4, 100 ng/mL); data are presented as mean ± SEM; asterisks, unpaired two-sided t-tests for comparing between control and treatments (* P < 0.05; ** P < 0.01). Exact P -values: LDN-193189, 0.0059/0.0075; K02288 , 0.0002/0.0042; mBMP4, 0.0265/0.0045 (low dose/high dose). Source data are provided as a file.

Article Snippet: For the BMP(−) condition, two small molecule inhibitors, LDN-193189 (Stemgent 04-0074) and K02288 (Tocris 4986) , were used to block the BMP pathway by inhibiting type I receptors for BMP ligand proteins.

Techniques: Recombinant, Immunostaining, Staining, Binding Assay, Control