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Key Points Fluorescence imaging can transform the way surgeries are performed, through the intraoperative identification of vital structures, lymph nodes and cancer in real time Near-infrared (NIR) fluorescence is particularly advantageous for use in clinical settings owing to improved depth penetration and low autofluorescence in the NIR wavelength range compared with shorter wavelengths Many targeted NIR fluorophores are currently in preclinical development; however, no cancer-targeted NIR fluorophores or devices for intraoperative NIR fluorescence detection of cancer have received commercial approval for human use Multiple early phase clinical trials are underway to evaluate targeted fluorophores for real-time, intraoperative cancer detection in humans The use of targeted fluorophores for the intraoperative detection of cancer might improve survival rates and functional outcomes in patients with cancer Currently, substantial regulatory challenges and clinical trial considerations constitute barriers for the adoption of fluorescence-guided surgery in clinical settings Intraoperative fluorescence enables highly specific real-time detection of tumours at the time of surgery. In particular, near-infrared (NIR) fluorescence is a promising tool currently being tested in clinical settings. Zhang et al . discuss the latest developments in NIR fluorophores, cancer-targeting strategies, and detection instrumentation for intraoperative cancer detection, as well as the challenges associated with their effective application in clinical settings. Over the past two decades, synergistic innovations in imaging technology have resulted in a revolution in which a range of biomedical applications are now benefiting from fluorescence imaging. Specifically, advances in fluorophore chemistry and imaging hardware, and the identification of targetable biomarkers have now positioned intraoperative fluorescence as a highly specific real-time detection modality for surgeons in oncology. In particular, the deeper tissue penetration and limited autofluorescence of near-infrared (NIR) fluorescence imaging improves the translational potential of this modality over visible-light fluorescence imaging. Rapid developments in fluorophores with improved characteristics, detection instrumentation, and targeting strategies led to the clinical testing in the early 2010s of the first targeted NIR fluorophores for intraoperative cancer detection. The foundations for the advances that underline this technology continue to be nurtured by the multidisciplinary collaboration of chemists, biologists, engineers, and clinicians. In this Review, we highlight the latest developments in NIR fluorophores, cancer-targeting strategies, and detection instrumentation for intraoperative cancer detection, and consider the unique challenges associated with their effective application in clinical settings.

There is an urgent need for new antibiotics against Gram-negative pathogens that are resistant to carbapenem and third-generation cephalosporins, against which antibiotics of last resort have lost most of their efficacy. Here we describe a class of synthetic antibiotics inspired by scaffolds derived from natural products. These chimeric antibiotics contain a β-hairpin peptide macrocycle linked to the macrocycle found in the polymyxin and colistin family of natural products. They are bactericidal and have a mechanism of action that involves binding to both lipopolysaccharide and the main component (BamA) of the β-barrel folding complex (BAM) that is required for the folding and insertion of β-barrel proteins into the outer membrane of Gram-negative bacteria. Extensively optimized derivatives show potent activity against multidrug-resistant pathogens, including all of the Gram-negative members of the ESKAPE pathogens 1 . These derivatives also show favourable drug properties and overcome colistin resistance, both in vitro and in vivo. The lead candidate is currently in preclinical toxicology studies that—if successful—will allow progress into clinical studies that have the potential to address life-threatening infections by the Gram-negative pathogens, and thus to resolve a considerable unmet medical need. A class of chimeric synthetic antibiotics that bind to lipopolysaccharide and BamA shows potent activity against multidrug-resistant Gram-negative bacteria, with the potential to address life-threatening infections.

The tetrasubstituted naphthalene diimide compound QN-302 binds to G-quadruplex (G4) DNA structures. It shows high potency in pancreatic ductal adenocarcinoma (PDAC) cells and inhibits the transcription of cancer-related genes in these cells and in PDAC animal models. It is currently in Phase 1a clinical evaluation as an anticancer drug. A study of structure–activity relationships of QN-302 and two related analogues (CM03 and SOP1247) is reported here. These have been probed using comparisons of transcriptional profiles from whole-genome RNA-seq analyses, together with molecular modelling and molecular dynamics simulations. Compounds CM03 and SOP1247 differ by the presence of a methoxy substituent in the latter: these two compounds have closely similar transcriptional profiles. Whereas QN-302 (with an additional benzyl-pyrrolidine group), although also showing down-regulatory effects in the same cancer-related pathways, has effects on distinct genes, for example in the hedgehog pathway. This distinctive pattern of genes affected by QN-302 is hypothesized to contribute to its superior potency compared to CM03 and SOP1247. Its enhanced ability to stabilize G4 structures has been attributed to its benzyl-pyrrolidine substituent fitting into and filling most of the space in a G4 groove compared to the hydrogen atom in CM03 or the methoxy group substituent in SOP1247.

The off-target toxicity of drugs targeted to proteins imparts substantial health and economic costs. Proteome interaction studies can reveal off-target effects with unintended proteins; however, little attention has been paid to intracellular RNAs as potential off-targets that may contribute to toxicity. To begin to assess this, we developed a reactivity-based RNA profiling methodology and applied it to uncover transcriptome interactions of a set of Food and Drug Administration-approved small-molecule drugs in vivo. We show that these protein-targeted drugs pervasively interact with the human transcriptome and can exert unintended biological effects on RNA functions. In addition, we show that many off-target interactions occur at RNA loci associated with protein binding and structural changes, allowing us to generate hypotheses to infer the biological consequences of RNA off-target binding. The results suggest that rigorous characterization of drugs’ transcriptome interactions may help assess target specificity and potentially avoid toxicity and clinical failures.Now a reactivity-based RNA profiling strategy can measure the global off-target transcriptome interactions of small-molecule drugs at single-nucleotide resolution. Using this approach, three FDA-approved drugs were evaluated, uncovering pervasive drug–RNA interactions and interactions that perturb RNA functions in cells.

The identification and prioritization of chemically tractable therapeutic targets is a significant challenge in the discovery of new medicines. We have developed a novel method that rapidly screens multiple proteins in parallel using DNA-encoded library technology (ELT). Initial efforts were focused on the efficient discovery of antibacterial leads against 119 targets from Acinetobacter baumannii and Staphylococcus aureus . The success of this effort led to the hypothesis that the relative number of ELT binders alone could be used to assess the ligandability of large sets of proteins. This concept was further explored by screening 42 targets from Mycobacterium tuberculosis . Active chemical series for six targets from our initial effort as well as three chemotypes for DHFR from M. tuberculosis are reported. The findings demonstrate that parallel ELT selections can be used to assess ligandability and highlight opportunities for successful lead and tool discovery. Encoded Library Technology (ELT) has streamlined the identification of chemical ligands for protein targets in drug discovery. Here, the authors optimize the ELT approach to screen multiple proteins in parallel and identify promising targets and antibacterial compounds for S. aureus , A. baumannii and M. tuberculosis .

Natural products have long been a source of useful biological activity for the development of new drugs. Their macromolecular targets are, however, largely unknown, which hampers rational drug design and optimization. Here we present the development and experimental validation of a computational method for the discovery of such targets. The technique does not require three-dimensional target models and may be applied to structurally complex natural products. The algorithm dissects the natural products into fragments and infers potential pharmacological targets by comparing the fragments to synthetic reference drugs with known targets. We demonstrate that this approach results in confident predictions. In a prospective validation, we show that fragments of the potent antitumour agent archazolid A, a macrolide from the myxobacterium Archangium gephyra , contain relevant information regarding its polypharmacology. Biochemical and biophysical evaluation confirmed the predictions. The results obtained corroborate the practical applicability of the computational approach to natural product ‘de-orphaning’. Natural products provide a rich source of leads for drug discovery. Now, a computational method is available that can be used to identify the macromolecular targets of these compounds. Much like medicinal chemists' reasoning, the software infers target information by comparing the substructures with those of drugs and other natural products with known targets.

As there are no clear on-target mechanisms that explain the increased risk for thrombosis and viral infection or reactivation associated with JAK inhibitors, the observed elevated risk may be a result of an off-target effect. Computational approaches combined with in vitro studies can be used to predict and validate the potential for an approved drug to interact with additional (often unwanted) targets and identify potential safety-related concerns. Potential off-targets of the JAK inhibitors baricitinib and tofacitinib were identified using two established machine learning approaches based on ligand similarity. The identified targets related to thrombosis or viral infection/reactivation were subsequently validated using in vitro assays. Inhibitory activity was identified for four drug-target pairs (PDE10A [baricitinib], TRPM6 [tofacitinib], PKN2 [baricitinib, tofacitinib]). Previously unknown off-target interactions of the two JAK inhibitors were identified. As the proposed pharmacological effects of these interactions include attenuation of pulmonary vascular remodeling, modulation of HCV response, and hypomagnesemia, the newly identified off-target interactions cannot explain an increased risk of thrombosis or viral infection/reactivation. While further evidence is required to explain both the elevated thrombosis and viral infection/reactivation risk, our results add to the evidence that these JAK inhibitors are promiscuous binders and highlight the potential for repurposing.

Kaempferia L., a medicinal genus of Zingiberaceae family, is widely distributed from India to Southeast Asia and is rich in terpenoids, flavonoids, phenolics, and volatile oils. Recently, it has gained attention for its diverse biological activities, including antioxidant, anticancer, analgesic, anti-inflammatory, and anti-tuberculosis effects. However, several Kaempferia species complexes exhibit similar morphological characteristics, making identification and classification challenging. This study integrates morphology, molecular phylogeny, and phytochemistry to identify and distinguish Kaempferia species. Phylogenetic relationships were reconstructed using four DNA barcoding markers: one nuclear region (ITS) and three chloroplast markers ( mat K, rbc L, and psb A- trn H). Untargeted metabolomic analysis using SPME-GC-MS, combined with multivariate statistical analyses, was employed to resolve species relationships and display volatile profiles among 15 Kaempferia species from two subgenera. A total of 217 metabolites were identified by the SPME-GC-MS technique. Variable Importance in Projection (VIP ≥ 1.5) analysis indicated 30 key metabolites, primarily sesquiterpenes, as specific chemotaxonomic markers. This study provides a comprehensive chemical profile of Kaempferia species and highlights metabolomic differences among them. Our findings emphasize the importance of integrating morphological, molecular, and phytochemical approaches for precise identification of closely related species, particularly within Kaempferia . This chemotaxonomic research also provides further applications for species authentication in pharmaceuticals and medicine.

High mobility group (HMG) proteins are intrinsically disordered nuclear non-histone chromosomal proteins that play an essential role in many biological processes by regulating the expression of numerous genes in eukaryote cells. HMGA proteins contain three DNA binding motifs, the “AT-hooks”, that bind preferentially to AT-rich sequences in the minor groove of B-form DNA. Understanding the interactions of AT-hook domains with DNA is very relevant from a medical point of view because HMGA proteins are involved in different conditions including cancer and parasitic diseases. We present here the first crystal structure (1.40 Å resolution) of the HMGA AT-hook 1 domain, bound to the minor groove of AT-rich DNA. In contrast to AT-hook 3 which bends DNA and shows a larger minor groove widening, AT-hook 1 binds neighbouring DNA molecules and displays moderate widening of DNA upon binding. The binding affinity and thermodynamics of binding were studied in solution with surface plasmon resonance (SPR)-biosensor and isothermal titration calorimetry (ITC) experiments. AT-hook 1 forms an entropy-driven 2:1 complex with (TTAA) 2 -containing DNA with relatively slow kinetics of association/dissociation. We show that N -phenylbenzamide-derived antikinetoplastid compounds ( 1 – 3 ) bind strongly and specifically to the minor groove of AT-DNA and compete with AT-hook 1 for binding. The central core of the molecule is the basis for the observed sequence selectivity of these compounds. These findings provide clues regarding a possible mode of action of DNA minor groove binding compounds that are relevant to major neglected tropical diseases such as leishmaniasis and trypanosomiasis.

PROTAC is a drug development technology that uses the Ubiquitin-Proteasome System (UPS) to degrade target proteins, and enhances the degradation ability of target proteins through E3 ubiquitin ligase, which can further enhance the anti-tumor effect of targeted drug molecules. In this study, a series of dual-target MDM2/MDMX stapled peptide PROTAC based on SM3-4 were designed and synthesized, and the stapled peptide PROTAC DSM3-2 and DSM3-5 screened in the study inhibited tumor cell growth in vitro at low µM concentrations. The results showed that the enhancement of stapled peptide activity was positively correlated with the increase of helicity, which provided an effective research basis for the dual-target anti-tumor stapled peptide PROTAC. Molecular docking experiments have shown that the binding peptide DSM3-2 can effectively bind to the target proteins MDM2 and MDMX to exert a dual targeting effect on tumor cells.