👤 Yang R

In the healthcare industry, the ever-increasing volume of clinical trial data presents challenges for ensuring drug safety and detecting adverse drug reactions (ADRs). This study aims to address the challenge of accurately detecting Serious Adverse Events (SAEs) in pharmacovigilance, a critical component in ensuring drug safety during and after clinical trials. The key problem lies in the underreporting and delayed detection of Adverse Drug Reactions (ADRs) due to the heterogeneous nature of medical data, class imbalance, and the limited scope of traditional monitoring techniques. This study proposes a hybrid AI-driven framework that integrates structured (e.g., patient demographics, lab results) and unstructured data (e.g., clinical notes) to detect ADRs using advanced deep learning and NLP methods. The objective is to outperform traditional signal detection methods and provide interpretable predictions to aid clinicians in real-time. By leveraging advanced Machine Learning (ML) and Deep Learning (DL) techniques, including Random Forests, Gradient Boosting Machines, and Convolutional Neural Networks (CNNs), our model aims to identify potential ADRs across different patient subgroups. Through meticulous feature engineering and the application of techniques to address data imbalance, our model demonstrates improved accuracy and interpretability in predicting ADRs. The CNN model achieved an accuracy of 85 %, outperforming traditional models, such as Logistic Regression (78 %) and Support Vector Machines (80 %). These findings suggest that specific demographic and clinical factors significantly influence the likelihood of adverse reactions, offering valuable insights for targeted monitoring and risk mitigation strategies[11]. This research underscores the potential of predictive modeling to enhance pharmacovigilance efforts and ensure safer clinical trial outcomes.•The research methodology includes a comparison of supervised learning algorithms, such as Logistic Regression, Random Forest, Gradient Boost, CNN, and genetic algorithms, to identify patterns and anomalies in clinical trial data. BERT and GPT, were also employed to provide the functionality of textual interactions over medical data.•Performance metrics such as accuracy, precision, recall, and F1-score were systematically applied to evaluate each model's performance. Among the models tested, the CNN model with BERT achieved the highest accuracy, providing valuable insights into the potential of deep learning for enhancing pharmacovigilance practices.•These findings suggest that an inclusion of diverse clinical data when supplied to advanced ML and NLP techniques can significantly improve the detection of ADRs, leading to better alignment with the fundamental principles of Good Clinical Practice (GCP). Show less

Psychiatric diseases are often treated with several drugs. In addition, the risk of developing somatic comorbidities which may require drug therapy is higher in patients with than in patients without psychiatric diseases. Further on, the risk of drug-drug interactions (DDI) increases with the number of drugs taken. The aim of this study was to analyze whether already known DDI between psychiatric drugs and somatic medications still occur in everyday clinical practice. Show less

Drug-drug interactions (DDI) are an important cause of adverse drug reactions (ADRs). Could large language models (LLMs) serve as valuable tools for pharmacovigilance specialists in detecting DDIs that lead to ADR notifications? Show less

N6-methyladenosine (m6A) represents the most common and thoroughly investigated RNA modification and exerts essential functions in regulating gene expression through influencing the RNA stability, the translation efficiency, alternative splicing, and nuclear export processes. The rapid development of high-throughput sequencing approaches, including miCLIP and MeRIP-seq, has profoundly transformed epitranscriptomics research. These techniques facilitate the detailed transcriptome-wide profiling of m6A modifications, shedding light on their crucial roles in diverse biological pathways. This review comprehensively examines the identification, mechanisms of regulation, and functional consequences of m6A modifications. It emphasizes their critical roles in physiological contexts, encompassing immune function, neuronal development, and the differentiation of stem cells. Additionally, the review discusses the contributions of m6A dysregulation to pathological conditions, including cancer, neurodegenerative diseases, and disorders of metabolism. We also discuss the development and application of machine-learning algorithms for m6A site prediction, emphasizing the integration of sequence-based, structural, and evolutionary conservation features to enhance the predictive accuracy. Furthermore, the potential of applying the findings from m6A research in precision medicine and drug development is examined. By synthesizing the current knowledge and emerging trends, this review aims to provide a comprehensive understanding of m6A biology and its translational potential, offering new perspectives for future research and therapeutic innovation. Show less

Small redox active molecules such as reactive nitrogen and oxygen species and hydrogen sulfide have emerged as important biological mediators that are involved in various physiological and pathophysiological processes. Advancement in understanding of cellular mechanisms that tightly regulate both generation and reactivity of these molecules is central to improved management of various disease states including cancer and cardiovascular dysfunction. Imbalance in the production of redox active molecules can lead to damage of critical cellular components such as cell membranes, proteins and DNA and thus may trigger the onset of disease. These small inorganic molecules react independently as well as in a concerted manner to mediate physiological responses. This review provides a general overview of the redox biology of these key molecules, their diverse chemistry relevant to physiological processes and their interrelated nature in cellular signaling. Show less

Ferroptosis, a novel form of regulated cell death induced by the excessive accumulation of lipid peroxidation products, plays a pivotal role in the suppression of tumorigenesis. Two prominent mitochondrial ferroptosis defense systems are glutathione peroxidase 4 (GPX4) and dihydroorotate dehydrogenase (DHODH), both of which are localized within the mitochondria. However, the existence of supplementary cellular defense mechanisms against mitochondrial ferroptosis remains unclear. Our findings unequivocally demonstrate that inactivation of mitochondrial respiratory chain complex I (MCI) induces lipid peroxidation and consequently invokes ferroptosis across GPX4 low-expression cancer cells. However, in GPX4 high expression cancer cells, the MCI inhibitor did not induce ferroptosis, but increased cell sensitivity to ferroptosis induced by the GPX4 inhibitor. Overexpression of the MCI alternative protein yeast NADH-ubiquinone reductase (NDI1) not only quells ferroptosis induced by MCI inhibitors but also confers cellular protection against ferroptosis inducers. Mechanically, MCI inhibitors actuate an elevation in the NADH level while concomitantly diminishing the CoQH2 level. The manifestation of MCI inhibitor-induced ferroptosis can be reversed by supplementation with mitochondrial-specific analogues of CoQH2. Notably, MCI operates in parallel with mitochondrial-localized GPX4 and DHODH to inhibit mitochondrial ferroptosis, but independently of cytosolically localized GPX4 or ferroptosis suppressor protein 1(FSP1). The MCI inhibitor IACS-010759, is endowed with the ability to induce ferroptosis while concurrently impeding tumor proliferation in vivo. Our results identified a ferroptosis defense mechanism mediated by MCI within the mitochondria and suggested a therapeutic strategy for targeting ferroptosis in cancer treatment. Show less

Reactive molecules, including oxygen and nitrogen species, serve dual roles in human physiology. While they function as essential signaling molecules under normal physiological conditions, they contribute to cellular dysfunction and damage when produced in excess by normal metabolism or in response to stressors. Oxidative/nitrosative stress is a pathological state, resulting from the overproduction of reactive species exceeding the antioxidant capacity of the body, which is implicated in several chronic human diseases. Antioxidant therapies aimed at restoring redox balance and preventing oxidative/nitrosative stress have demonstrated efficacy in preclinical models. However, their clinical applications have met with inconsistent success owing to efficacy, safety, and bioavailability concerns. This summative review analyzes the role of reactive species in human pathophysiology, the mechanisms of action of antioxidant protection, and the challenges that hinder their translation into effective clinical therapies in order to evaluate potential emerging strategies such as targeted delivery systems, precision medicine, and synergistic therapeutic approaches, among others, to overcome current limitations. By integrating recent advances, this review highlights the value of targeting reactive species in the prevention and management of chronic diseases. Show less

Here, we shed physico-chemical light on major kinase signal transduction cascades in cell proliferation in the Ras network, MAPK and PI3K/AKT/mTOR. The cascades respond to external stimuli. The kinases are allosterically activated and relay the signal, leading to cell growth and division. The pathways are crosslinked, with the output of one pathway influencing the other. The effectiveness of their allosteric signaling relay stems from coordinated speed and precision. These qualities are essential for cell life-yet exactly how they are obtained and regulated has challenged the community over four decades. Here, we define their nature by their kinases' repertoires, substrate specificities and breadth, activation and autoinhibition mechanisms, catalytic rates, interactions, and their dilution state. The cascades are lodged in a dense molecular condensate phase at the membrane adjoining RTK clusters, where their assemblies promote specific, productive signaling. Aiming to shed further physico-chemical light, we ask (i) how starting the cascades with a single substrate and ending with hundreds is still labeled specific; (ii) what we can learn from their different number of mutations; and (iii) why B-Raf unique side-to-side inverse dimerization slows ERK activation and signaling. We point to the (iv) chemical mechanics of the distributions of rates of the crucial MAPK cascade: slower at the top and rapid at the bottom. Finally, the cascades provide inspiration for pharmacological perspectives. Collectively, our updated physico-chemical outlook provides the molecular basis of targeting protein kinases in cancer and spans mechanisms and scales, from conformational landscapes to membraneless organelles, cells and systems levels. Show less

The aim of the UniProt Knowledgebase (UniProtKB; https://www.uniprot.org/) is to provide users with a comprehensive, high-quality and freely accessible set of protein sequences annotated with functional information. In this publication, we describe ongoing changes to our production pipeline to limit the sequences available in UniProtKB to high-quality, non-redundant reference proteomes. We continue to manually curate the scientific literature to add the latest functional data and use machine learning techniques. We also encourage community curation to ensure key publications are not missed. We provide an update on the automatic annotation methods used by UniProtKB to predict information for unreviewed entries describing unstudied proteins. Finally, updates to the UniProt website are described, including a new tab linking protein to genomic information. In recognition of its value to the scientific community, the UniProt database has been awarded Global Core Biodata Resource status. Show less

Rare diseases affect over 300 million people worldwide and are often caused by genetic variants. While variant detection has become cost-effective, interpreting these variants-particularly collecting literature-based evidence like ACMG/AMP PM3-remains complex and time-consuming. Show less

Despite the vast number of enzymatic kinetic measurements reported across decades of biochemical literature, the majority of relational enzyme kinetic data-linking amino acid sequence, substrate identity, kinetic parameters, and assay conditions-remains uncollected and inaccessible in structured form. This constitutes a significant portion of the "dark matter" of enzymology. Unlocking these hidden data through automated extraction offers an opportunity to expand enzyme dataset diversity and size, critical for building accurate, generalizable models that drive predictive enzyme engineering. To address this limitation, we built EnzyExtract, a large language model-powered pipeline that automates the extraction, verification, and structuring of enzyme kinetics data from scientific literature. By processing 137,892 full-text publications (PDF/XML), EnzyExtract collected more than 218,095 enzyme-substrate-kinetics entries, including 218,095 kcat and 167,794 Km values. These entries are mapped to enzymes spanning 3569 unique four-digit EC numbers, with a total of 84,464 entries assigned at least a first-digit EC number. EnzyExtract identified 89,544 unique kinetic entries (kcat and Km combined) absent from BRENDA, significantly expanding the known enzymology dataset. The newly curated dataset was compiled into a database named EnzyExtractDB. EnzyExtract demonstrates high accuracy when benchmarked against manually curated datasets and strong consistency with BRENDA-derived data. To create model-ready datasets, enzyme and substrate sequences were aligned to UniProt and PubChem, yielding 92,286 high-confidence, sequence-mapped kinetic entries. To assess the practical utility of our dataset, we retrained several state-of-the-art kcat predictors (including MESI, DLKcat, and TurNuP) using EnzyExtractDB. Across held-out test sets, all models demonstrate improved predictive performance in terms of RMSE, MAE, and R2, highlighting the value of high-quality, large-scale, literature-derived EnzyExtractDB for enhancing predictive modeling of enzyme kinetics. The EnzyExtract source code and the database are openly available at https://github.com/ChemBioHTP/EnzyExtract, and an interactive demo can be accessed via Google Colab at https://colab.research.google.com/drive/1MwKSEZzLPNOseksRshbzkkFoO_cgJhva. Show less

Title: The role of ancillary ligands on benzodipyridophenazine-based Ru(II)/Ir(III) complexes in dark and light toxicity against TNBC cells. Abstract: In this study, we investigated the impact of ancillary ligands on the anticancer activity of benzodipyridophenazine-based Ru(II) and Ir(III) complexes (Ru1, Ru2, Ir1, and Ir2). These metal complexes displayed three significant absorption bands attributed to the ligand-centered (LC) transitions, ligand-to-ligand charge transfer (LLCT), and metal-to-ligand charge transfer (MLCT). Binding studies of biomolecules were performed with the complexes along with the ligand, and it was found that after binding with Ru(II)/Ir(III), the properties of the ligands were enhanced. In vitro screening revealed that complex [(η5-Cp*)IrIIICl(κ2-N,N-benzo[i]dipyrido[3,2-a:2',3'-c])phenazine] (Ir1) exhibited the highest potency and selectivity (IC50 ∼ 2.14 μM, PI > 13) under yellow light irradiation. The photo-toxicity trend was Ir1 > Ru1 > Ir2 ≫ Ru2, which was found to be directly correlated with the singlet oxygen quantum yield (1O2). Chloro-substituted complexes (Ir1 and Ru1) were effective for hypoxic tumor treatment, particularly Ir1, which could generate high amounts of reactive oxygen species (ROS, type I PDT) in cells under photo irradiation. The high value of fluorescence quantum yield (fφ = 0.26) and significant emission at λ = 571 nm of Ir1 were certainly useful for bio-imaging applications. Colocalisation and DCFDA studies of Ir1 revealed that it can accumulate in the mitochondria, leading to depolarization of the mitochondrial membrane. These studies confirm that the complex Ir1 is a promising candidate for TNBC treatment in hypoxic tumors, with efficacy comparable to the current PDT drug Photofrin. Show less

Bioenergetic therapy targeting mitochondrial bioenergy is a promising therapeutic strategy for cancer. However, its clinical efficacy is limited by the metabolic adaptability of tumor cells, as they can switch between glycolytic and oxidative phosphorylation metabolic phenotypes to maintain energy homeostasis. In this study, we discovered 1,8-naphthyridine-piperazine-dithiocarbamate ruthenium(II) polypyridyl complexes (RuL1) that enhanced energy deprivation by inhibiting the activity of mitochondrial complex I and III, thereby disrupting oxidative phosphorylation. Simultaneously, RuL1 inhibits glycolysis while unexpectedly activating antitumor immunity. This dual metabolic-immunological targeting resulted in enhanced anticancer activity against MGC-803 cells. To the best of our knowledge, RuL1 is the first ruthenium polypyridyl complex reported to achieve high anticancer activity through dual metabolic inhibition. Show less

Intracellular imaging of anticancer metallodrugs often relies on prelabeling with organic fluorophores, which significantly affects their physicochemical properties and intracellular distribution. On the other hand, the reported postlabeling strategies based on click-chemistry reactions require cell fixation and permeabilization. Here, this study presents a postlabeling approach based on the catalyst-free, inverse electron-demand Diels-Alder reaction (iEDDA) between a strained fluorescein-tagged bicyclononyne derivative (BCN-FAM) and half-sandwich Ir(III) complexes containing bidentate ligands comprising a tetrazine (Tz-R,R') entity. Five half-sandwich Ir(III) complexes with formula [Cp*Ir(Tz-R,R')Cl]^0/+ have been synthesized and fully characterized, including the X-ray crystal structures of three of the five derivatives. Investigations of their stability and their reactivity in aqueous solution and in a model iEDDA reaction reveal the strong influence of the tetrazine ligand structure on the chemical properties of the corresponding complexes. A highly cytotoxic metallodrug candidate (Ir-C,N_Ph,Me) is identified from biological studies, and chemical reactivity studies disclose an unusual preference for binding of methionine over cysteine. Postlabeling of Ir-C,N_Ph,Me in live HeLa cells highlights its preferential accumulation within the nucleus, suggesting its retention through covalent modifications of nuclear proteins in good agreement with other half-sandwich iridium(III) complexes. Show less

Title: Highly effective Ru(II) and Os(II) half-sandwich complexes induce cytotoxicity in cancer cells through combined mitochondrial and endoplasmic reticulum stress. Abstract: A series of ruthenium(II) and osmium(II) half-sandwich complexes was synthesized and characterized for its potential as a new class of anticancer agents. The complexes feature polycyclic aromatic hydrocarbon (PAH)-substituted Schiff bases and were rationally designed to combine the redox-modulating MoA of half-sandwich Ru, Rh, Os and Ir complexes, connected with their ability to induce the formation of various reactive oxygen species (ROS), with the ability of PAH-substituents to target and disrupt DNA. The complexes [Ru(η6-pcym)Cl(L)]PF6 (1-4) and [Os(η6-pcym)Cl(L)]PF6 (5-8) were stable in aqueous environments, in contrast to the rapid degradation observed for the co-studied rhodium(III) (9-12) and iridium(III) (13-16) [M(η5-Cp∗)Cl(L)]PF6 complexes; L = ethane-1,2-diamine-based Schiff bases (L1-L4) bearing two terminal PAH substituents 2-naphtyl (for L1), 9-anthracenyl (for L2), 9-phenanthrenyl (L3) or 1-pyrenyl (L4); pcym = 1-methyl-4-(propan-2-yl)benzene (p-cymene), Cp∗ = pentamethylcyclopentadienyl. Biological testing demonstrated that 1-8 possess significant antiproliferative activity against various lung cancer cell lines, including those resistant to cisplatin, with Os(II) complex 5 showing the highest cytotoxicity. Treatment with these complexes led to the activation of stress-related gene pathways, including unconventional endoplasmic reticulum stress, apoptotic signalling, and mitochondrial membrane depolarization. Activation of p21/GADD45A pathway indicates DNA-damage response, as well. Notably, these complexes did not induce significant inflammatory responses, a notable advantage over cisplatin. The results highlight the potential of Ru and Os half-sandwich complexes as alternative metallodrugs, capable of overcoming platinum resistance and minimizing inflammatory side effects. This study suggests that these compounds could serve as a promising class of anticancer agents for future clinical development. Show less

The co-administration of drugs known to interact greatly impacts morbidity, mortality, and health economics. This study aims to examine the drug-drug interaction (DDI) phenomenon with a large-scale longitudinal analysis of age and gender differences found in drug administration data from three distinct healthcare systems. Show less

Expert curation is essential to capture knowledge of enzyme functions from the scientific literature in FAIR open knowledgebases but cannot keep pace with the rate of new discoveries and new publications. In this work we present EnzChemRED, for Enzyme Chemistry Relation Extraction Dataset, a new training and benchmarking dataset to support the development of Natural Language Processing (NLP) methods such as (large) language models that can assist enzyme curation. EnzChemRED consists of 1,210 expert curated PubMed abstracts where enzymes and the chemical reactions they catalyze are annotated using identifiers from the protein knowledgebase UniProtKB and the chemical ontology ChEBI. We show that fine-tuning language models with EnzChemRED significantly boosts their ability to identify proteins and chemicals in text (86.30% F1 score) and to extract the chemical conversions (86.66% F1 score) and the enzymes that catalyze those conversions (83.79% F1 score). We apply our methods to abstracts at PubMed scale to create a draft map of enzyme functions in literature to guide curation efforts in UniProtKB and the reaction knowledgebase Rhea. Show less

In the era of high throughput sequencing, special software is required for the clinical evaluation of genetic variants. We developed REEV (Review, Evaluate and Explain Variants), a user-friendly platform for clinicians and researchers in the field of rare disease genetics. Supporting data was aggregated from public data sources. We compared REEV with seven other tools for clinical variant evaluation. REEV (semi-)automatically fills individual ACMG criteria facilitating variant interpretation. REEV can store disease and phenotype data related to a case to use these for phenotype similarity measures. Users can create public permanent links for individual variants that can be saved as browser bookmarks and shared. REEV may help in the fast diagnostic assessment of genetic variants in a clinical as well as in a research context. REEV (https://reev.bihealth.org/) is free and open to all users and there is no login requirement. Show less

PubTator 3.0 (https://www.ncbi.nlm.nih.gov/research/pubtator3/) is a biomedical literature resource using state-of-the-art AI techniques to offer semantic and relation searches for key concepts like proteins, genetic variants, diseases and chemicals. It currently provides over one billion entity and relation annotations across approximately 36 million PubMed abstracts and 6 million full-text articles from the PMC open access subset, updated weekly. PubTator 3.0's online interface and API utilize these precomputed entity relations and synonyms to provide advanced search capabilities and enable large-scale analyses, streamlining many complex information needs. We showcase the retrieval quality of PubTator 3.0 using a series of entity pair queries, demonstrating that PubTator 3.0 retrieves a greater number of articles than either PubMed or Google Scholar, with higher precision in the top 20 results. We further show that integrating ChatGPT (GPT-4) with PubTator APIs dramatically improves the factuality and verifiability of its responses. In summary, PubTator 3.0 offers a comprehensive set of features and tools that allow researchers to navigate the ever-expanding wealth of biomedical literature, expediting research and unlocking valuable insights for scientific discovery. Show less

The need for a systematic approach in developing new metal-based drugs with dual anticancer-antimicrobial properties is emphasized by the vulnerability of cancer patients to bacterial infections. In this context, a novel organometallic assembly was designed, featuring ruthenium(II) coordination with p-cymene, one chlorido ligand, and a bidentate neutral Schiff base derived from 4-methoxybenzaldehyde and N,N-dimethylethylenediamine. The compound was extensively characterized in both solid-state and solution, employing single crystal X-ray diffraction, nuclear magnetic resonance, infrared, ultraviolet-visible spectroscopy, and density functional theory, alongside Hirshfeld surface analysis. The hydrolysis kinetic was thoroughly investigated, revealing the important role of the chloro-aqua equilibrium in the dynamics of binding with deoxyribonucleic acid and bovine serum albumin. Notably, the aqua species exhibited a pronounced affinity for deoxyribonucleic acid, engaging through electrostatic and hydrogen bonding interactions, while the chloro species demonstrated groove-binding properties. Interaction with albumin revealed distinct binding mechanisms. The aqua species displayed covalent binding, contrasting with the ligand-like van der Waals interactions and hydrogen bonding observed with the chloro specie. Molecular docking studies highlighted site-specific interactions with biomolecular targets. Remarkably, the compound exhibited wide spectrum moderate antimicrobial activity against Staphylococcus aureus, Pseudomonas aeruginosa, and Candida albicans, coupled with low micromolar cytotoxic activity against human colorectal adenocarcinoma cells and significant activity against human leukemic monocyte lymphoma cells. The presented findings encourage further development of this compound, promising avenues for its evolution into a versatile therapeutic agent targeting both infectious diseases and cancer. Show less

Title: pH-Responsive, Self-Assembled Ruthenium Nanodrug: Dual Impact on Lysosomes and DNA for Synergistic Chemotherapy and Immunogenic Cell Death. Abstract: Several DNA-damaging antitumor agents, including ruthenium complexes, induce immunogenic cell death (ICD). In this study, an arginyl-glycyl-aspartic acid (RGD) peptide-modified carboline ruthenium complex (KS-Ru) is synthesized as a chemotherapeutic nanodrug and an ICD inducer. The RGD peptide, an integrin ligand, provides tumor-specific targeting and promotes self-assembly of the KS-Ru complex. The pH-responsive self-assembly is assessed through transmission and scanning electron microscopy. Additionally, in vitro cytotoxic activity and anti-metastasis ability are evaluated using MTT and Transwell assays, respectively, along with cellular immunofluorescence staining and imaging flow cytometry. The ability of the complex to inhibit primary tumor formation and lung metastasis in vivo is evaluated using Lewis lung cancer and A549 xenograft models. Furthermore, the tumor immune microenvironment is evaluated using single-cell flow mass cytometry. KS-Ru translocates to the nucleus, causing DNA damage and inducing ICD. Within the lysosomes, KS-Ru self-assembled into nanoflowers, leading to lysosomal swelling and apoptosis. Notably, the as-synthesized pH-dependent ruthenium nanomedicine achieves dual functionality-chemotherapy and immunotherapy. Moreover, the pH-responsive self-assembly of KS-Ru enables simultaneous mechanisms in the lysosome and nucleus, thereby lowering the likelihood of drug resistance. This study provides valuable insight for the design of novel ruthenium-based nanoantitumor drugs. Show less

Title: Trinuclear ruthenium(II) polypyridyl complexes: Evaluation as photosensitizers for enhanced cervical cancer treatment. Abstract: Trinuclear ruthenium(II) polypyridyl complexes anchored to benzimidazole-triazine / trisamine scaffolds were investigated as photosensitizers for photodynamic therapy. The trinuclear complexes were noted to produce a significant amount of singlet oxygen in both DMF and aqueous media, are photostable and show appreciable emission quantum yields (ɸem). In our experimental setting, despite the moderate phototoxic activity in the HeLa cervical cancer cell line, the phototoxic indices (PI) of the trinuclear complexes are superior relative to the PIs of a clinically approved photosensitizer, Photofrin®, and the pro-drug 5-aminolevulinic acid (PI: >7 relative to PI: >1 and PI: 4.4 for 5-aminolevulinic acid and Photofrin®, respectively). Furthermore, the ruthenium complexes were noted to show appreciable long-term cytotoxicity upon light irradiation in HeLa cells in a concentration-dependent manner. Consequently, this long-term activity of the ruthenium(II) polypyridyl complexes embodies their ability to reduce the probability of the recurrence of cervical cancer. Taken together, this presents a strong motivation for the development of polymetallic complexes as anticancer agents. Show less

Glioblastoma multiforme (GBM) is the most common highly aggressive malignant brain tumor, with a very limited chance for survival post-diagnosis and post-treatment. Despite significant advancement in GBM genomics implicated in molecularly targeted chemotherapies, the prognosis remains poor and requires new drug discovery approaches. We used fluoropyrimidine 5-fluorouracil (5-FU), an antimetabolite anticancer drug conjugated or 'caged' within a lipophilic Ru(II)-diphosphine (dppe) core formulated as [Ru^II(dppe)₂(5-FU)]PF₆ (Ru-DPPE-5FU), where dppe = 1,2-bis(diphenylphosphino)ethane, and evaluated its in vitro cytotoxicity in depth with aggressive GBM cells (LN229). The hydrophilic nature of 5-FU limits its passage through the blood-brain barrier (BBB), which prevents its effective accumulation and efficacy for GBM tumors. Herein, we attempted to modulate the lipophilicity of 5-FU by inserting it within a well-designed lipophilic {Ru(dppe)₂}-core with anticipated higher efficiency towards GBM. The physicochemical properties of [Ru^II(dppe)₂(5-FU)]PF₆ (Ru-DPPE-5FU) were studied using various spectroscopic and analytical techniques. The molecular structure was determined using X-ray crystallography, showing a distorted {RuP₄NO} octahedral geometry with bidentate (N, O) binding of 5-FU and its aromatization in the Ru(II)-bound form. The ³¹P-NMR spectra of Ru-DPPE-5FU showed four closely spaced distinct ³¹P-signals, indicating four unique chemical environments around P, and the strong coupling constants between them make it a second-order spectrum. The Ru^II/Ru^III redox potential in Ru-DPPE-5FU shifted by ∼0.91 V towards the anodic region as compared to its precursor complex cis-[Ru(dppe)₂Cl₂] (Ru-DPPE-Cl). DFT-based theoretical calculations have been performed to correlate the experimental electronic absorption spectra and redox behaviours of the complexes. The electrostatic potential (ESP) plots indicate the delocalization of the charge density on the O-/F-atom from the 5-FU ligand towards Ru(II) upon its complexation. The antioxidant properties of all the compounds were quantified by a 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay. The hyphenation of the 5-fluorouracil (5-FU) ligand to the lipophilic {Ru(dppe)₂}-core endowed lipophilicity to Ru-DPPE-5FU with higher in vitro cytotoxicity (IC₅₀ = 2.37 μM) against the LN229 GBM cells as compared to the hydrophilic 5-FU, suggesting efficient cellular uptake. Further biological assays indicated that the complex is highly potent in inhibiting significant proliferation and spheroid formation and restricting the migratory potentials of the GBM cells. Increased caspase 3/7 activity and the presence of apoptotic bodies at the center of 3-D GBM spheroids as revealed by AO/EB dual staining indicated a deeper penetration of the lipophilic complex. The Ru-DPPE-5FU complex displayed lower cytotoxicity in HaCaT normal cells (IC₅₀ = 7.27 μM) in comparison to LN229 cancer cells with a selectivity index (S.I.) of ≥3. Overall, the synergism and caging of 5-FU within the hydrophobic {Ru(dppe)₂}-core improves the pharmacokinetic profile of Ru-DPPE-5FU as a potent anticancer agent for glioblastoma. Show less

Title: Insights into Mechanisms and Promising Triple Negative Breast Cancer Therapeutic Potential for a Water-Soluble Ruthenium Compound. Abstract: Triple negative breast cancer (TNBC) represents a subtype of breast cancer that does not express the three major prognostic receptors of human epidermal growth factor receptor 2 (HER2), progesterone (PR), and estrogen (ER). This limits treatment options and results in a high rate of mortality. We have reported previously on the efficacy of a water-soluble, cationic organometallic compound (Ru-IM) in a TNBC mouse xenograft model with impressive tumor reduction and targeted tumor drug accumulation. Ru-IM inhibits cancer hallmarks such as migration, angiogenesis, and invasion in TNBC cells by a mechanism that generates apoptotic cell death. Ru-IM displays little interaction with DNA and appears to act by a P53-independent pathway. We report here on the mitochondrial alterations caused by Ru-IM treatment and detail the inhibitory properties of Ru-IM in the PI3K/AKT/mTOR pathway in MDA-MB-231 cells. Lastly, we describe the results of an efficacy study of the TNBC xenografted mouse model with Ru-IM and Olaparib monotherapy and combinatory treatments. We find 59% tumor shrinkage with Ru-IM and 65% with the combination. Histopathological analysis confirmed no test-article-related toxicity. Immunohistochemical analysis indicated an inhibition of the angiogenic marker CD31 and increased levels of apoptotic cleaved caspase 3 marker, along with a slight inhibition of p-mTOR. Taken together, the effects of Ru-IM in vitro show similar trends and translation in vivo. Our investigation underscores the therapeutic potential of Ru-IM in addressing the challenges posed by TNBC as evidenced by its robust efficacy in inhibiting key cancer hallmarks, substantial tumor reduction, and minimal systemic toxicity. Show less

A new Ru(II) arene chlorido organometallic complex [(η⁶-p-cymene)(L)RuCl]PF₆ (named as pCYRuL) using 2-bis(quinolin-2-ylmethylene) hydrazine (L) was developed that exhibits potent anticancer activity against castration-resistant prostate cancer (CRPC) (IC₅₀ = 0.71 μM), and it is 45 times more effective than the standard drug cisplatin (IC₅₀ = 31.3 μM) in a castration-resistant human prostatic adenocarcinoma cell line (PC-3) but non-toxic in normal human kidney cells (HK2) as well as normal breast cells (MCF10A) and found that pCYRuL exerted anticancer activity via apoptosis induction and cell cycle arrest in the G2/M phase of PC-3 cells. Show less

Six polypyridyl Ru(II) complexes were designed for single-molecule photodynamic and sonodynamic therapy (PDT/SDT) synergistic multimodal anticancer toward cisplatin-resistant NSCLC. They demonstrated lowest 3ES with distinct intraligand transition nature, which is beneficial for singlet oxygen generation. Remarkable quantum yields of both singlet oxygen and superoxide anion under either 808 nm laser irradiation or ultrasonic treatment and could induce apoptosis and ferroptosis of A549R cells. Cytotoxicity experiments clearly demonstrated a synergistic effect between PDT and SDT. The relationship between the structures of these complexes and their cellular biological mechanisms has been explored in detail. Using a single-molecule sensitizer to achieve synergistic PDT/SDT may provide valuable insights for the treatment of drug-resistant tumors that located deeply and in hypoxic microenvironment. Show less

Title: Analysis of antiproliferative activity of new half-sandwich arene Ru(II) thiophene based aroylhydrazone complexes. Abstract: Efforts in researching the efficient anti-tumor properties of three novel arene ruthenium(II) complexes incorporating thiophene-based aroylhydrazone ligands have been undertaken. The complexes' elemental composition was [(η6-p-cymene)Ru(L)Cl]. They were comprehensively characterized through elemental and spectroscopic analyses (FT-IR, UV-vis, NMR, and HR-MS). Single crystal X-ray diffraction studies revealed a pseudo-octahedral geometry with bidentate coordination of the ligands in a representative complex. The in vitro assessment of the complexes' cancer cell growth inhibition was conducted using the MTT assay against A549 (human lung carcinoma), HeLa (human cervical carcinoma), HuH-7 (hepatocellular carcinoma), and NIH-3T3 (mouse fibroblast non-cancerous cell line). Results indicated significant cytotoxicity across all cancer cell lines, with IC50 concentrations of complex 2 being 6.8 μM for A549, 11.6 μM for HeLa, and 9.4 μM for HuH-7, compared to cisplatin with IC50 values of 18.9 μM, 17.68 μM, and 24 μM respectively. Notably, complex 2 demonstrated particularly promising cytotoxicity against all tested cancerous cell lines. Fluorescent staining analysis such as acridine orange/ethidium bromide (AO-EB) and HOECHST 33342 revealed cell death mechanisms involving membrane disintegration and nuclear condensation following treatment with complex 2. Further studies were conducted to measure reactive oxygen species (ROS) levels using the dichlorodihydrofluorescein diacetate (DCFH-DA) assay, and mitochondrial membrane potential (MMP) was assessed using the JC-1 dye assay. These studies demonstrated that complex 2 increased ROS levels, decreased membrane potential, and promoted mitochondrial dysfunction-mediated cell death pathways. Additionally, flow cytometry analysis, utilizing dual staining of Annexin V-FITC and propidium iodide (PI), was employed to quantitatively study apoptosis induction. Show less

Title: Green Light-Triggered Photocatalytic Anticancer Activity of Terpyridine-Based Ru(II) Photocatalysts. Abstract: The relentless increase in drug resistance of platinum-based chemotherapeutics has opened the scope for other new cancer therapies with novel mechanisms of action (MoA). Recently, photocatalytic cancer therapy, an intrusive catalytic treatment, is receiving significant interest due to its multitargeting cell death mechanism with high selectivity. Here, we report the synthesis and characterization of three photoresponsive Ru(II) complexes, viz., [Ru(ph-tpy)(bpy)Cl]PF6 (Ru1), [Ru(ph-tpy)(phen)Cl]PF6 (Ru2), and [Ru(ph-tpy)(aip)Cl]PF6 (Ru3), where, ph-tpy = 4'-phenyl-2,2':6',2″-terpyridine, bpy = 2,2'-bipyridine, phen = 1,10-phenanthroline, and aip = 2-(anthracen-9-yl)-1H-imidazo[4,5-f][1,10] phenanthroline, showing photocatalytic anticancer activity. The X-ray crystal structures of Ru1 and Ru2 revealed a distorted octahedral geometry with a RuN5Cl core. The complexes showed an intense absorption band in the 440-600 nm range corresponding to the metal-to-ligand charge transfer (MLCT) that was further used to achieve the green light-induced photocatalytic anticancer effect. The mitochondria-targeting photostable complex Ru3 induced phototoxicity with IC50 and PI values of ca. 0.7 μM and 88, respectively, under white light irradiation and ca. 1.9 μM and 35 under green light irradiation against HeLa cells. The complexes (Ru1-Ru3) showed negligible dark cytotoxicity toward normal splenocytes (IC50s > 50 μM). The cell death mechanistic study revealed that Ru3 induced ROS-mediated apoptosis in HeLa cells via mitochondrial depolarization under white or green light exposure. Interestingly, Ru3 also acted as a highly potent catalyst for NADH photo-oxidation under green light. This NADH photo-oxidation process also contributed to the photocytotoxicity of the complexes. Overall, Ru3 presented multitargeting synergistic type I and type II photochemotherapeutic effects. Show less

Title: Microtubule-Targeting NAP Peptide-Ru(II)-polypyridyl Conjugate As a Bimodal Therapeutic Agent for Triple Negative Breast Carcinoma. Abstract: Triple-negative breast cancer (TNBC) poses significant treatment challenges due to its high metastasis, heterogeneity, and poor biomarker expression. The N-terminus of an octapeptide NAPVSIPQ (NAP) was covalently coupled to a carboxylic acid derivative of Ru(2,2'-bipy)32+ (Rubpy) to synthesize an N-stapled short peptide-Rubpy conjugate (Ru-NAP). This photosensitizer (PS) was utilized to treat TNBC through microtubule (MT) targeted chemotherapy and photodynamic therapy (PDT). Ru-NAP formed more elaborate molecular aggregates with fibrillar morphology as compared to NAP. A much higher binding affinity of Ru-NAP over NAP toward β-tubulin (KRu-NAP: (6.8 ± 0.55) × 106 M-1; KNAP: (8.2 ± 1.1) × 104 M-1) was observed due to stronger electrostatic interactions between the MT with an average linear charge density of ∼85 e/nm and the cationic Rubpy part of Ru-NAP. This was also supported by docking, simulation, and appropriate imaging studies. Ru-NAP promoted serum stability, specific binding of NAP to the E-site of the βIII-tubulin followed by the disruption of the MT network, and effective singlet oxygen generation in TNBC cells (MDA-MB-231), causing cell cycle arrest in the G2/M phase and triggering apoptosis. Remarkably, MDA-MB-231 cells were more sensitive to Ru-NAP compared to noncancerous human embryonic kidney (HEK293 cells) when exposed to light (LightIC50Ru-NAP[HEK293]: 17.2 ± 2.5 μM, compared to LightIC50Ru-NAP[MDA-MB-231]: 32.5 ± 7.8 nM, DarkIC50Ru-NAP[HEK293]: > 80 μM, compared to DarkIC50Ru-NAP[MDA-MB-231]: 2.9 ± 0.5 μM). Ru-NAP also effectively inhibited tumor growth in MDA-MB-231 xenograft models in nude mice. Our findings provide strong evidence that Ru-NAP has a potential therapeutic role in TNBC treatment. Show less

Nuclear factor kappa beta (NF-κB) plays a pivotal role in breast cancer, particularly triple-negative breast cancer, by promoting inflammation, proliferation, epithelial-mesenchymal transition, metastasis, and drug resistance. Upregulation of NF-κB boosts vascular endothelial growth factor (VEGF) expression, assisting angiogenesis. The Ru(II) complexes of methyl- and dimethylpyrazolyl-benzimidazole N,N donors inhibit phosphorylation of ser536 in p65 and translocation of the NF-κB heterodimer (p50/p65) to the nucleus, disabling transcription to upregulate inflammatory signaling. The methyl- and dimethylpyrazolyl-benzimidazole inhibit VEGFR2 phosphorylation at Y1175, disrupting downstream signaling through PLC-γ and ERK1/2, ultimately suppressing Ca(II)-signaling. Partial release of the antiangiogenic ligand in a reactive oxygen species-rich environment is possible as per our observation to inhibit both NF-κB and VEGFR2 by the complexes. The complexes are nontoxic to zebrafish embryos up to 50 μM, but the ligands show strong in vivo antiangiogenic activity at 3 μM during embryonic growth in Tg(fli1:GFP) zebrafish but no visible effect on the adult phase. Show less