Kalaba P, Böhm MP, D̵ikić F
… +11 more, Tomašević N, Drdla-Schutting R, Hasinger S, Ines DM, Wolf A, Belil-Catalina M, Bryant SD, Spetea M, Gruber CW, Muttenthaler M, Keimpema E
The kappa opioid receptor (KOR) controls a wide variety of biological processes, including pain and reward responses. However, its precise spatiotemporal location remains poorly understood due to limited selective molecu...The kappa opioid receptor (KOR) controls a wide variety of biological processes, including pain and reward responses. However, its precise spatiotemporal location remains poorly understood due to limited selective molecular tools. We addressed this problem by developing dynorphin-based fluorescent KOR tracers that are selective for KOR over its closely related mu- and delta-family members (MOR, DOR). Our lead tracer is highly selective for KOR (>360-fold over MOR and DOR) and can effectively visualize KORs in the somatodendritic compartment of cultured primary cortical neurons, as well as in superficial layer neurons of the spinal cord dorsal horn. Furthermore, it blocked the KOR agonist U50,488-induced reduction in the excitatory drive of spinal cord neurons. The developed tracer can also be immobilized with paraformaldehyde and used for imaging, rendering it a highly valuable tool for mapping KOR expression in physiological and pathophysiological contexts.
Liu X, Xiao Y, Zhou Y
… +25 more, Teng Y, Zou J, Zhou Y, Fan X, Zhao J, Qiu J, Tang L, Qiu Z, Xu J, Luo H, Pan X, Xu W, Ren B, Gou K, Liu C, Ren Y, Song J, Gao P, Zhou X, Zhang L, Qian X, Lei J, Cen X, Luo Y, Zhao Y
The guanine nucleotide exchange factor SOS1 has emerged as an attractive therapeutic target for various KRAS-driven tumors. Herein, we employed a structure-based drug design strategy to develop a series of novel quinazol...The guanine nucleotide exchange factor SOS1 has emerged as an attractive therapeutic target for various KRAS-driven tumors. Herein, we employed a structure-based drug design strategy to develop a series of novel quinazoline-derived molecules. This effort yielded highly potent and selective SOS1 inhibitors, and , which displayed high SOS1 binding affinity, potently disrupted the SOS1-KRAS interaction, and inhibited nucleotide exchange in WT and multiple KRAS variants. Moreover, both compounds showed submicromolar 3D-antiproliferative activity across a panel of CRC cells, induced G phase arrest, and suppressed MAPK and PI3K signaling pathways. Furthermore, and demonstrated favorable safety profiles with no observed adverse effects at levels of 500 and 700 mg/kg, respectively. At doses of 60 mg/kg, they achieved significant tumor growth inhibition (75.1% and 86.2%, respectively) in HCT116 xenograft models without significant toxicity. Collectively, this study identifies potent drug candidates with strong pan-KRAS therapeutic efficacy against colorectal cancer.
Hypoxia-inducible factor 2α (HIF-2α) is recognized as a key oncogenic driver in clear cell renal cell carcinoma (ccRCC), the most prevalent type of kidney cancer. Here, we describe the discovery of a highly potent and se...Hypoxia-inducible factor 2α (HIF-2α) is recognized as a key oncogenic driver in clear cell renal cell carcinoma (ccRCC), the most prevalent type of kidney cancer. Here, we describe the discovery of a highly potent and selective tetralin-based HIF-2α inhibitor, casdatifan (), originating from previously identified tetrahydroquinolines reported in the Part 1 companion manuscript. Casdatifan demonstrates a potentially best-in-class clinical profile. In a healthy volunteer study (NCT05117554), casdatifan exhibited a favorable pharmacokinetic profile, with an approximate 24-h half-life suitable for once-daily oral administration. Casdatifan has shown promising clinical activity in the ARC-20 ccRCC platform study, both as monotherapy and in combination with the VEGFR tyrosine kinase inhibitor (TKI) cabozantinib. Currently, casdatifan is being evaluated in a Phase 3 trial in combination with cabozantinib (NCT07011719) in patients with advanced ccRCC.
HDAC6 is a promising therapeutic target for the treatment of cancer and neurodegenerative and inflammatory diseases. We have developed a thiazolyl alkyl hydroxamate scaffold as an HDAC6-selective inhibitor. Herein, we sy...HDAC6 is a promising therapeutic target for the treatment of cancer and neurodegenerative and inflammatory diseases. We have developed a thiazolyl alkyl hydroxamate scaffold as an HDAC6-selective inhibitor. Herein, we synthesized new thiazolyl hydroxamate derivatives to investigate the effects of aliphatic linker length and cap group rigidity on HDAC6 selectivity. Hydroxy-3-(2-(6-methoxynaphthalen-2-yl)thiazol-4-yl)propanamide () was identified as a potent HDAC6 inhibitor (IC = 25.56 nM) with ∼500-fold selectivity over HDAC1. Docking and MD simulations revealed that the 6-methoxy-β-naphthalene cap of stably occupies a hydrophobic pocket containing HDAC6-specific nonconserved residues, providing a rationale for novel HDAC6 inhibitor design. Treatment with upregulated BDNF (exons I and IV), and other neurogenesis-related genes in neural progenitor cells. In vivo, improved memory performance in scopolamine-treated memory-impaired mice in the passive avoidance test. These findings suggest that enhances neuroplasticity-related pathways and warrants further investigation as a potential therapeutic candidate for neurodegenerative diseases.
The PDZ domain of neuronal nitric oxide synthase (nNOS-PDZ) plays a crucial role in regulating serotonin signaling in the forebrain and has emerged as a promising target for developing rapid-acting antidepressants. Here,...The PDZ domain of neuronal nitric oxide synthase (nNOS-PDZ) plays a crucial role in regulating serotonin signaling in the forebrain and has emerged as a promising target for developing rapid-acting antidepressants. Here, we report the identification of , a potent and selective small-molecule inhibitor of nNOS-PDZ. induces a substantial thermal shift (Δ) of 5.44 °C in a differential scanning fluorimetry (DSF) assay and displays an IC of 0.76 ± 0.07 μM in a fluorescence polarization (FP) assay. The cocrystal structure of the nNOS-PDZ- complex reveals key binding interactions. , produces rapid, dose-dependent antidepressant effects in mouse models of depression induced by chronic unpredictable mild stress (CUMS) and chronic corticosterone treatment, with no evidence of addictive potential or motility-related side effects. Together, these results establish as a potent and selective nNOS-PDZ inhibitor, providing a promising lead compound for the development of antidepressants.
Despite recent advances in immunotherapy for microsatellite instability-high (MSI-H) tumors, challenges of resistance persist, necessitating alternative therapeutic approaches. The synthetic lethal interaction between WR...Despite recent advances in immunotherapy for microsatellite instability-high (MSI-H) tumors, challenges of resistance persist, necessitating alternative therapeutic approaches. The synthetic lethal interaction between WRN helicase inhibition and MSI status presents a promising therapeutic strategy. Guided by the key structural features of the WRN- complex, we rationally designed two classes of WRN inhibitors─spirocyclic compounds and benzo-fused heterocyclic analogs─by targeting the solvent-exposed region. Among these, exhibited potent in vitro activity and excellent cellular selectivity. Compared with in vivo, demonstrated more favorable oral pharmacokinetic properties and superior antitumor efficacy at 10 mg/kg, comparable efficacy at 20 mg/kg, and achieved complete tumor regression at 40 mg/kg. Preliminary safety evaluation further indicated that possesses a favorable safety profile. These findings support as a promising WRN inhibitor candidate for the treatment of MSI-H tumors.
The transcription factor tailless (TLX, NR2E1) is expressed in neuronal stem cells and retinal progenitor cells and is thought to maintain their self-renewal by balancing proliferation and differentiation. It is consider...The transcription factor tailless (TLX, NR2E1) is expressed in neuronal stem cells and retinal progenitor cells and is thought to maintain their self-renewal by balancing proliferation and differentiation. It is considered as a master regulator of neurogenesis and a promising target in neurodegeneration. Here, we developed highly potent and selective activators of TLX' transcriptional repressor activity by systematic extension of previously optimized fragment TLX ligands and tuning of the substitution pattern. An optimized TLX activator with nanomolar potency and pronounced selectivity was studied for its transcriptomic effects by RNAseq, which demonstrated upregulation of genes associated with ATP production, lysosomal function, and vesicular transport. Moreover, the mitochondrial quality control-associated PTEN-induced kinase 1 (PINK1) was induced, and the amyloidogenic β-secretase (BACE) was downregulated, supporting anti-neurodegenerative effects of TLX modulation on the transcriptional level.
Proteolysis-targeting chimeras (PROTACs) are heterobifunctional molecules that recruit an E3 ligase to a protein of interest, thereby promoting ubiquitin transfer and subsequent proteasomal degradation. Formation of the...Proteolysis-targeting chimeras (PROTACs) are heterobifunctional molecules that recruit an E3 ligase to a protein of interest, thereby promoting ubiquitin transfer and subsequent proteasomal degradation. Formation of the ternary complex is a key step in PROTAC-induced degradation, and structural insight into these complexes is important for rational PROTAC design. Here, we present a computational approach for sampling PROTAC-induced ternary complexes by reducing the search space to the conformational degrees of freedom of the linker. Evaluated on 40 cocrystal ternary complex structures, the method achieved retrospective success rates of 97% and 50% at Cα-RMSD thresholds of 10 and 4 Å from the crystal structures, respectively. Using unbound protein structures as input, the predicted ternary complexes remained within 7 Å of the experimental structures across six WDR5-PROTAC-VHL complexes. Our open-source software, TERNIFY, enables ternary-complex modeling in a standalone workflow without separate protein-protein docking and linker-sampling steps.
Herrmann A, Hahn F, Wangen C
… +24 more, Wagner S, Cordsmeier A, Irrgang P, Weil T, Hunszinger V, Groß R, Heinen N, Pfaender S, Westhoven S, Reuter S, Schedel M, Uhlig N, Eberlein V, Issmail L, Grunwald T, Klopfleisch R, Ensser A, Tenbusch M, Münch J, Sparrer KMJ, Marschall M, Kohlhof H, Vitt D, Gege C
Emerging and re-emerging viral infections demand the rapid development of broad-spectrum antivirals. Host-directed therapies targeting cellular metabolic pathways required for viral replication offer a promising strategy...Emerging and re-emerging viral infections demand the rapid development of broad-spectrum antivirals. Host-directed therapies targeting cellular metabolic pathways required for viral replication offer a promising strategy with a low risk of resistance. Dihydroorotate dehydrogenase (DHODH), the rate-limiting enzyme in pyrimidine synthesis, is essential for the replication of many human pathogenic viruses. Several DHODH inhibitors, including vidofludimus calcium, are under clinical investigation for viral diseases, such as coronavirus disease 19 (COVID-19). We report medicinal chemistry optimization of vidofludimus, yielding more potent derivatives with improved DHODH inhibition across mammalian species and enhanced activity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Optimized compounds also showed broad-spectrum antiviral activity against enveloped and nonenveloped DNA and RNA viruses and a retrovirus, with single-digit nanomolar potency and no detectable cytotoxicity. Selectivity indices exceeded 50,000, highlighting the therapeutic potential of this target. These findings identify this compound class as a promising starting point for host-directed antivirals (HDAs), as well as for pandemic preparedness and applications in other disease areas.
Cyclin K is overexpressed in multiple tumors and plays critical roles in tumorigenesis, making it a promising therapeutic target. Although the antitumor potential of Cyclin K-targeting molecular glues, their clinical app...Cyclin K is overexpressed in multiple tumors and plays critical roles in tumorigenesis, making it a promising therapeutic target. Although the antitumor potential of Cyclin K-targeting molecular glues, their clinical application is limited by insufficient efficacy and tumor selectivity. Herein, we developed , a photomolecular glue that releases Cyclin K molecular glue and phototherapeutic agent in hypoxic tumor microenvironments, thereby enhancing tumor selectivity. Network pharmacology and Western blotting analysis demonstrated that the combination of and synergistically enhances DNA damage and apoptosis in breast cancer cells compared to either monotherapy. In vivo, exhibited potent tumor growth inhibition with excellent biosafety and biocompatibility. This intelligent design framework significantly improves the therapeutic efficacy and selectivity of molecular glues. It is expected to be generalizable to other molecular glues and phototherapeutic agents.
Mannino MP, Gokanapalle A, Patil S
… +13 more, Kooner AS, Meena CL, Medcalf M, Vilza I, Barks J, Fu Y, Xia J, Nix JC, Nelson C, Fremont D, Dhillon A, Sibley LD, Janetka JW
is an important opportunistic pathogen that infects many individuals and threatens the health of those with compromised immunity. Current therapies are unable to eradicate chronic infections and pose risks of adverse rea...is an important opportunistic pathogen that infects many individuals and threatens the health of those with compromised immunity. Current therapies are unable to eradicate chronic infections and pose risks of adverse reactions. Using X-ray structure-based drug design, we have developed a new series of biaryl-substituted pyrazolopyrimidine inhibitors of the essential parasite enzyme calcium-dependent protein kinase 1 (TgCDPK1). These inhibitors have excellent potency against the enzyme and antiparasitic activity. We further optimized the compounds for increased metabolic stability, lowered plasma protein binding, decreased efflux, and improved pharmacokinetics (PK). Several of the inhibitors had desirable PK with high oral bioavailability, low clearance, and extended half-life, leading to excellent compound exposure in the plasma and brain over a 24-h period. Three compounds were tested during acute infection in both immunocompetent and immunocompromised mice. We identified as a promising preclinical candidate to treat toxoplasmosis.
Kamiya Y, Sato F, Sakashita K
… +12 more, Ariyoshi J, Oyama H, Liu X, Yamada N, Miyata K, Muttaqien SE, Noda Y, Kato N, Maruyama S, Kinoh H, Kataoka K, Asanuma H
Acyclic artificial nucleic acids, serinol nucleic acid (SNA) and l-threoninol nucleic acid (L-TNA), are promising next-generation nucleic acid therapeutics with strong nuclease resistance and stable RNA hybridization, e...Acyclic artificial nucleic acids, serinol nucleic acid (SNA) and l-threoninol nucleic acid (L-TNA), are promising next-generation nucleic acid therapeutics with strong nuclease resistance and stable RNA hybridization, eliminating the need for phosphorothioate (PS) modifications that are associated with toxicities and complicate manufacturing due to diastereomer generation. However, both platforms suffer from self-interactions in self-complementary regions, limiting their therapeutic utility. To overcome this, we incorporated pseudocomplementary bases, 2,6-diaminopurine (D) and 2-thiouracil (sU), into SNA and L-TNA oligonucleotides. This strategy effectively suppressed self-interactions and enhanced the RNA affinity. As a proof of concept, SNA and L-TNA oligonucleotides targeting miR-21, which has a self-complementary region, with D and sU substitutions demonstrated significantly improved anti-miR-21 activity in cancer cell lines. Furthermore, PS-free L-TNA incorporating D and sU effectively suppressed tumor growth with low toxicity when delivered via unit polyion complexes. This platform offers a safer and more effective strategy for antisense oligonucleotide therapeutics.
We report the design, synthesis, and characterization of a series of targeted degraders directed against testis-specific serine/threonine kinases TSSK1 and TSSK2. A stable CHO-K1 cell line expressing HiBiT-tagged TSSK1 e...We report the design, synthesis, and characterization of a series of targeted degraders directed against testis-specific serine/threonine kinases TSSK1 and TSSK2. A stable CHO-K1 cell line expressing HiBiT-tagged TSSK1 enabled quantitative cellular profiling and identified compound as a potent TSSK1 degrader with a DC of 10 nM and a of 68% after 48 h. In contrast, ex vivo incubation of CD1 mouse sperm with degrader induced up to an 80% reduction of the TSSK2 isoform within 4 h and translated into profound functional loss, resulting in a 97% reduction in sperm motility and near-complete loss of in vitro fertilization. Both alkyl- and PEG-linked degraders displayed metabolic -dealkylation and high efflux, and therefore will require optimization. These data provide proof of concept that targeted degradation can occur within sperm cells, leading to a disruption of sperm function and encouraging further optimization toward in vivo evaluation for male contraception.
Chemical modification is essential for improving the stability and knockdown efficiency of siRNAs. However, the combinatorial complexity of modification types and positions makes rational design difficult. Here, we propo...Chemical modification is essential for improving the stability and knockdown efficiency of siRNAs. However, the combinatorial complexity of modification types and positions makes rational design difficult. Here, we propose MEG-mod, a deep learning framework for predicting the knockdown efficiency of chemically modified siRNAs. By integrating a literature-reading agent, manual curation, and public database resources, we construct an expanded data set. MEG-mod jointly models sequence context, physicochemical properties, chemical modification features, and duplex structural relationships. A structure-aware Transformer-based graph neural network captures base-pairing and adjacency dependencies within double-stranded siRNAs, while a modification-base fusion module models context-dependent modification effects. MEG-mod outperforms existing methods, achieving a pearson correlation coefficient of 0.9171. The attention mechanism enables interpretable analysis of key modification positions and modification types, and provides recommendations consistent with reported experimental designs. MEG-mod is available as a public web server (https://lmmd.ecust.edu.cn/megmod/), providing a practical tool for prediction and candidate prioritization of chemically modified siRNAs.
A fused dihydropyrrolidino-pyrimidine hit with low lipophilicity and excellent ligand efficiency was identified in a biochemical screen of the Global Health Chemical Diversity Library (GHCDL) against lysyl-tRNA syntheta...A fused dihydropyrrolidino-pyrimidine hit with low lipophilicity and excellent ligand efficiency was identified in a biochemical screen of the Global Health Chemical Diversity Library (GHCDL) against lysyl-tRNA synthetase (KRS). Structure-guided lead optimization delivered analogues with potent parasite growth inhibition, excellent biochemical and cellular selectivity (>1000-fold), and oral efficacy in the malaria NOD-scid-IL2Rγ (SCID) mouse model. Structural information and computational methods were deployed to identify a potent and selective basic KRS inhibitor () with an extended half-life to reduce the dose regimen to a single-dose cure. Compound displayed a long half-life across preclinical species, favorable safety, and activity across species as well as against drug-resistant and sensitive strains and field isolates. Unfortunately, lacked oral bioavailability, which could not be mitigated with a prodrug approach. Nevertheless, learnings from this series will assist future KRS programs in delivering a clinical candidate with this novel mode of action.
Previously drugged therapeutic targets have continued to attract substantial scientific and clinical interest, resulting in numerous FDA approvals for new chemical entities (NCEs) over the past 15 years. This sustained p...Previously drugged therapeutic targets have continued to attract substantial scientific and clinical interest, resulting in numerous FDA approvals for new chemical entities (NCEs) over the past 15 years. This sustained productivity demonstrates that these established therapeutic drug targets remain a central foundation of modern drug discovery, supporting not only incremental improvements in efficacy and safety but also the development of innovative medicinal chemistry strategies and novel mechanisms of action. In this Perspective, we provide a comprehensive analysis of the contributions of previously drugged therapeutic targets to FDA-approved small-molecule drugs between 2010 and 2025, with an emphasis on therapeutic innovation based on several representative therapeutic drug targets across central nervous system, infectious disease, and oncology indications. The design principles and translational insights derived from these paradigmatic cases highlight the enduring value of these "evergreen" therapeutic drug targets and may inform future efforts to develop more effective, differentiated, and resistance-resilient therapeutics.
Photodynamic therapy (PDT) is a promising precision treatment for cancer, yet its clinical translation is often hindered by the lack of near-infrared (NIR) photosensitizers that simultaneously offer efficient reactive ox...Photodynamic therapy (PDT) is a promising precision treatment for cancer, yet its clinical translation is often hindered by the lack of near-infrared (NIR) photosensitizers that simultaneously offer efficient reactive oxygen species (ROS) generation capability, deep-tissue penetration, and favorable biocompatibility. Herein, we report two novel bisbenzoselenophene[]-fused azaBODIPY derivatives, and , via a one-pot CuI-catalyzed cyclization/BF-complexation strategy. They display strong NIR absorption (λ up to 726 nm) and achieve ROS generation quantum yields reaching 0.27. When formulated into nanoparticles, demonstrates exceptional biocompatibility with minimal dark toxicity, along with potent photocytotoxicity against 4T1, B16, and HeLa cells, effectively suppressing tumor cell proliferation. In vivo studies in 4T1-tumor-bearing mice reveal a high tumor-growth inhibition rate (tumor growth inhibition = 73%) without apparent systemic toxicity. Given their strong NIR absorption, efficient Type I/II ROS generation, and minimal dark toxicity, these selenium-incorporated azaBODIPYs represent a promising class of photosensitizers for clinically translatable PDT.
Bacteria possess innate tumor tropism and immunostimulatory properties, yet their efficacy as monotherapy is limited. Here, we report rational cationic interface engineering of bacteria through a tricationic heptamethine...Bacteria possess innate tumor tropism and immunostimulatory properties, yet their efficacy as monotherapy is limited. Here, we report rational cationic interface engineering of bacteria through a tricationic heptamethine photosensitizer () to construct a well-defined bacteria-photosensitizer hybrid (). Tricationic modification strengthens bacterial adhesion and solubility, stabilizing the hybrid and promoting tumor accumulation through motility and hypoxia-directed localization. Under near-infrared irradiation (785 nm), mediates simultaneous photothermal (η = 54.9%) and photodynamic effects and displays robust photostability. induces immunogenic cell death, promotes dendritic-cell maturation, and amplifies T-cell activation, ultimately leading to substantial solid tumor regression (94.4% inhibition in vivo). This work demonstrates that cationic photosensitizer-functionalized bacteria can enhance bacterial tumor targeting and photoimmune therapeutic efficacy, providing a chemically guided strategy for bacteria-based cancer treatment.
Activation of extrasynaptic δ-GABARs represents a promising strategy for rapid-acting antidepressant therapy in major depressive disorder (MDD). Here, we report the discovery and pharmacological characterization of a nov...Activation of extrasynaptic δ-GABARs represents a promising strategy for rapid-acting antidepressant therapy in major depressive disorder (MDD). Here, we report the discovery and pharmacological characterization of a novel series of thiazolo[4,5-]pyrimidin-7(6)-one derivatives as potent positive allosteric modulators selective for δ-GABARs. Systematic SAR exploration identified compound as a lead candidate, which demonstrated high potency on the extrasynaptic receptor subtype (α4β3δ: 950% current enhancement at 10 μM, EC = 0.8 μM) while maintaining favorable modulation of synaptic subtypes. , exerted rapid-acting antidepressant effects in both the mouse tail suspension test and the chronic restraint stress-induced depression model, with no addictive behaviors observed. These effects were completely abolished in δ-subunit knockout mice, confirming target engagement. Furthermore, significantly enhanced NREM sleep in a -chlorophenylalanine-induced insomnia model, highlighting potential dual efficacy in MDD with comorbid sleep disturbance. Collectively, these findings position as a promising clinical candidate for next-generation rapid-acting antidepressant therapy.
Urbanowicz KA, Marek-Urban PH, Wrochna K
… +11 more, Rogalska M, Lewandowska-Andrałojć A, Kotwica K, Pluczyk-Małek S, Blacha-Grzechnik A, Nasiłowska I, Trzaskowski M, Gdesz J, Mierzejewska J, Staniszewska M, Durka K
A series of heavy-atom-free C-BODIPY photosensitizers based on five different types of fused-ring organoboron scaffolds was designed for the application in antifungal photodynamic therapy. The dyes were functionalized wi...A series of heavy-atom-free C-BODIPY photosensitizers based on five different types of fused-ring organoboron scaffolds was designed for the application in antifungal photodynamic therapy. The dyes were functionalized with a positively charged quaternary ammonium group or zwitterionic 3-(ethyldimethylammonio)propane-1-sulfonate unit. Spectroscopic, electrochemical, and photocatalytic studies supported by DFT calculations revealed the crucial role of the organoboron structure on triplet-state generation. Most of the BODIPY complexes display high ROS generation with a type I/type II ROS ratio depending on the electronic structure of the boracycle unit. Antifungal studies demonstrated remarkable efficacy against the opportunistic yeast at low concentrations (1.6 μg/mL), achieving up to a 7-log reduction in the planktonic cells and significant photoactivity toward the fungal biofilm, reaching up to 4.3-log reduction in MFC values. The studies on the cell death mechanism revealed that cells undergo apoptosis upon photoinactivation. Furthermore, complexes were proven to reduce cell adhesion to biotic surfaces, preventing biofilm formation.