Distinct Mechanisms Of Action Research Articles

Isoquinolinequinone N-oxides with diverging mechanisms of action induce collateral sensitivity against multidrug resistant cancer cells.

Multidrug resistance (MDR) is a major challenge in cancer research. Collateral sensitizers, compounds that exploit the enhanced defense mechanisms of MDR cells as weaknesses, are a proposed strategy to overcome MDR. Our previous work reported the synthesis of two novel Isoquinolinequinone (IQQ) N-oxides that induce collateral sensitivity in MDR ABCB1-overexpressing non-small cell lung cancer (NSCLC) and colorectal cancer cells. Herein, we aimed to investigate underlying mechanisms of antitumor and collateral sensitivity activity of these compounds. We evaluated their effect on cancer cell viability, proliferation, cell cycle profile, and studied their cytotoxicity in non-tumorigenic cells. Their antitumor effect was further studied using NSCLC and colorectal cancer MDR spheroids. To understand underlying collateral sensitivity mechanisms, we assessed the effect on rhodamine-123 accumulation, ROS production, GSH/GSSG balance and expression of key proteins associated with metabolism and redox balance. Both compounds reduced the viability of MDR cells, as 2D cultures or as spheroids, without decreasing the growth of a human nontumorigenic cell line, and increased rhodamine-123 accumulation in MDR NCI-H460/R cells. Moreover, RK2 increased ROS, disrupted GSH balance, and altered expression of proteins associated with oxidative stress protection, particularly in NCI-H460/R cells. The collateral sensitivity effect of RK3 could not be attributed to redox balance disruption, but increased IDH1 expression following treatment suggests a potential metabolic shift in MDR cells. These findings highlight RK2 and RK3 as promising candidates for next stages of drug development. Their distinct mechanisms of action could lead to therapeutic solutions for MDR-related cancers, specifically linked to ABCB1 overexpression.

Tofacitinib and budesonide treatment affect stemness and chemokine release in IBD patient-derived colonoids

Restoration of the intestinal epithelial barrier is crucial for achieving mucosal healing, the therapeutic goal for inflammatory bowel disease (IBD). During homeostasis, epithelial renewal is maintained by crypt stem cells and progenitors that cease to divide as they differentiate into mature colonocytes. Inflammation is a major effector of mucosal damage in IBD and has been found to affect epithelial stemness, regeneration and cellular functions. However, the impact of immune cell-modulating IBD drugs on epithelial homeostasis and repair is poorly understood. It is likely that these drugs will have distinct mechanisms of action (MOA) in intestinal epithelium relevant for homeostasis that will vary among patients. We investigated cellular effects of pan-Janus Kinase (JAK) inhibitor tofacitinib and the corticosteroid budesonide on uninflamed and TNF + Poly(I:C) stimulated human colon organoids (colonoids) from healthy donors and IBD-patients. Our findings reveal that although both tofacitinib and budesonide exhibit anti-inflammatory effects, tofacitinib increased colonoid size and proliferation during differentiation, and promoted epithelial stemness. In contrast, budesonide decreased colonoid size and showed no consistent effect on proliferation or stemness. Our study demonstrates the value of employing human colonoids to investigate how IBD drugs affect intestinal epithelial cells and inter-individual variations relevant to mucosal healing and personalized IBD treatment.

Multi-pronged molecular insights into flavonoid-mediated inhibition of squalene epoxidase: a pathway to novel therapeutics.

Squalene epoxidase (SQLE) is a crucial enzyme in the sterol biosynthesis pathway and a promising target for therapeutic intervention in hypercholesterolemia and fungal infections. This study evaluates the inhibitory potential of six flavonoids namely silibinin, baicalin, naringenin, chrysin, apigenin-7-O-glucoside, and isorhamnetin against SQLE using an integrative approach combining in silico and experimental methods. Molecular docking revealed that apigenin-7-O-glucoside, silibinin, and baicalin displayed the highest binding affinities (-10.7, -10.2, and -10.0 kcal mol-1, respectively) and robust interactions with the SQLE binding site. These findings were corroborated by 200 ns molecular dynamics (MD) simulations, which demonstrated stable binding trajectories, minimal structural fluctuations, a thermodynamically favored potential energy landscape (PEL) and favorable MM/PBSA binding free energies for three flavonoids. Experimental validation via in vitro inhibition assays confirmed the computational predictions, with apigenin-7-O-glucoside emerging as the most potent inhibitor (IC50 = 1.74 ± 0.05 μM), followed by silibinin (IC50 = 1.88 ± 0.28 μM) and baicalin (IC50 = 2.50 ± 0.46 μM). Enzyme kinetics studies revealed distinct mechanisms of action: apigenin-7-O-glucoside exhibited competitive inhibition, while silibinin and baicalin showed mixed inhibition. Furthermore, in silico ADMET analysis indicated favorable pharmacokinetic and pharmacodynamic profiles for these flavonoids, with silibinin demonstrating particularly high bioavailability and lipophilicity. This study highlights apigenin-7-O-glucoside, silibinin, and baicalin as potent SQLE inhibitors with promising therapeutic potential. The congruence between in silico predictions and experimental results underscores the reliability of computational approaches in drug discovery, paving the way for future preclinical development of these compounds as novel SQLE-targeted therapeutics.

Synergistic Anti-Helicobacter pylori Effects of Takifugu obscurus Skin Peptides and Lactobacillus plantarum: A Potential Gastric Health Dietary Supplement

Helicobacter pylori (H. pylori) infection is a widespread gastric infectious disease, posing significant challenges due to the increasing prevalence of antibiotic resistance. This study aimed to evaluate the synergistic antibacterial activity of Takifugu obscurus skin peptides (TSPs) and the cell-free supernatant of Lactobacillus plantarum WUH3 (LCFS) in developing a potential green and efficient dietary supplement therapy. Using enzymatic hydrolysis and ultrafiltration techniques, the most bioactive peptide fraction, TSPb (1–3 kDa), was identified. The effects of TSPb and LCFS—both individually and in combination—on H. pylori biofilm function, membrane morphology, and internal structure were systematically analyzed using urease activity, N-phenyl naphthylamine (NPN) uptake, nucleic acid leakage, scanning electron microscopy (SEM), and infrared (IR) spectroscopy. The results showed that both LCFS and TSPb significantly inhibited H. pylori urease activity, with inhibition rates of 53.60% and 54.21% at 24 h, respectively, and the highest inhibition rate of 74.64% was observed with their combined treatment. SEM, NPN fluorescence, and nucleic acid leakage analyses revealed distinct mechanisms of action for each treatment. LCFS treatment caused membrane surface loosening and morphological deformation, while TSPb induced the formation of localized membrane pores. IR spectroscopy further confirmed that the combined treatment led to a more severe disruption of the lipid and protein structure within the bacterium. Overall, compared to individual treatments, the combination of TSPb and LCFS exhibited enhanced intracellular penetration and a more significant effect on bacterial viability. This study successfully identified TSPb as a highly bioactive peptide and elucidated its potential synergistic antibacterial mechanism with LCFS. These findings provide scientific evidence for the development of functional antimicrobial foods and gastric health dietary supplements, offering a promising strategy for the prevention and management of H. pylori infections.

Eyelash trichomegaly complicating pembrolizumab for colorectal cancer.

Pembrolizumab is an immune checkpoint inhibitor widely administered for the treatment of various malignancies. Despite its effectiveness, its distinctive mechanism of action may lead to immune-related adverse events, most frequently affecting cutaneous tissues. Hair-related adverse events, although uncommon, include conditions such as alopecia areata and alterations in hair texture or type. A 63-year-old male patient presented with eyelash trichomegaly following two cycles of pembrolizumab infusion. The patient experienced discomfort due to the eyelash trichomegaly, prompting him to consider discontinuing the treatment. However, the patient's neoplastic disease demonstrated a complete radiologic response, which encouraged him to continue the therapy. This case illustrates a unique documentation of pembrolizumab-induced eyelash trichomegaly. While immune checkpoint inhibitors like pembrolizumab are known to cause hair-related adverse events, reports of eyelash trichomegaly remain rare. This case emphasizes the necessity for clinicians to remain vigilant about such uncommon side effects to ensure comprehensive patient management.

Multi-assay assessment of cytotoxicity reveals multiple mechanisms of action in 3D microtissues

Cell viability assays are an integral component of toxicology and high-throughput drug screening studies; however, many assays rely on a single biomarker of cell death which provides an incomplete assessment of cell viability. Here, we introduce an innovative approach that combines data from multiple assays using a linear mixed effects regression model and principal component analysis. We explored the cytotoxic response of various assay-treatment combinations using four assays with distinct mechanisms of action and seven different treatments across three types of microtissue cultures. The multi-assay data revealed the presence of multifaceted cellular injuries which highlight the need for multimodal approaches to better understand complex disruptions to viability. By incorporating outputs from the four assays, we introduced a new lethal concentration threshold that captures changes from different cellular injuries to provide a more comprehensive evaluation of cytotoxicity. Overall, the proposed approach provides a unique opportunity to analyze data from multiple assays in a holistic manner to improve the predictive power of drug screening and toxicology studies.

Modular Synthesis of Anti-HER2 Dual-Drug Antibody-Drug Conjugates Demonstrating Improved Toxicity.

Antibodies have gained clinical success in the last two decades for the targeted delivery of highly toxic small molecule chemotherapeutics. Yet antibody-drug conjugates (ADCs) often fail in the clinic due to the development of resistance. The delivery of two mechanistically distinct small molecule drugs on one antibody is of increasing interest to overcome these challenges with single-drug ADCs. We have developed a modular synthetic strategy for the construction of a library of 19 dual-drug ADCs where drugs are conjugated through unnatural cyclopentadiene-containing amino acids and native cysteine residues on an anti-HER2 trastuzumab scaffold. Importantly, this strategy utilizes the same functional group on the linker-drug construct; this allows for the facile addition of drugs at either conjugation site and enables the evaluation of different drug-to-antibody ratios and combinations of drug pairs. We tested the library on high- and mid-HER2 expressing cell lines and observed increased toxicity in several dual-drug ADCs compared with single-drug constructs. The strategy developed herein provides a method for the facile synthesis, characterization, and evaluation of dual-payload ADCs. Simultaneous delivery of combinations of drugs with distinct mechanisms of action is critical for the next generation of targeted drug delivery.

P0056 Efficacy of Infliximab in Biologic-Experienced Patients with Inflammatory Bowel Disease: A Retrospective Study

Abstract Background Infliximab is typically the first biologic choice for patients with inflammatory bowel disease (IBD), and its role is well-established in biologic-naive patients. However, based on patient characteristics, an alternative biologic may sometimes be selected as the initial treatment, with numerous options currently available. In cases of intolerance or loss of response to these alternatives, the role of Infliximab in biologic-experienced patients remains unclear1,2. This study aims to evaluate the efficacy of Infliximab in a cohort of biologic-experienced patients. Methods We conducted a retrospective study at a tertiary centre, including all biologic-experienced patients with IBD who were subsequently treated with Infliximab. Clinical records were thoroughly reviewed to collect data on demographics, prior and current medication, and clinical, endoscopic, analytical and histological disease activity. Statistical analysis was performed using SPSS Statistics version 26®. Results Seventeen patients were included, of whom 6 females, with a mean age of 45.8 ± 17.6 years. Twelve patients with ulcerative colitis (UC) and five with Crohn’s disease (CD) were identified. Of the 17 patients, 10 had previously been treated with an anti-TNFα agent (either Adalimumab or Golimumab), 4 with Vedolizumab, 1 with Guselkumab and 2 with an anti-TNFα (both Adalimumab) followed by other drugs with distinct mechanism of action (Vedolizumab alone in 1, Ustekinumab and Tofacitinib in the other). All these drugs were suspended due to primary failure (PF), except for two (both Adalimumab) due to secondary failure (SF). Currently, 8 patients are continuing treatment with Infliximab, of which 5 are UC patients, all in clinical remission and 1 in deep remission; and 3 CD patients, all in clinical remission with a current Harvey-Bradshaw score of 1. Of those who discontinued Infliximab (9 patients), 4 were due to PF, 3 due to SF, 1 due to death (not related with disease or drug administration) and the other due to treatment refusal. Conclusion Infliximab appears to be effective in certain biologic-experienced IBD patients and given its lower cost this treatment option may be viable. Nonetheless, larger series are needed for a more comprehensive understanding, to allow an inferential statistical analysis and define the best candidates to Infliximab.

Real-world safety of maribavir: a retrospective study based on signal detection in the FDA adverse event reporting system.

Maribavir is a novel antiviral agent targeting cytomegalovirus through inhibition of the UL97 protein kinase, exhibiting a distinct mechanism of action. However, limited data are available on its safety profile post-marketing. This study aimed to evaluate the adverse events (AEs) associated with maribavir using the Food and Drug Administration's Adverse Event Reporting System (FAERS), providing insights to inform clinical practice. We conducted a retrospective analysis of maribavir-related adverse event reports from the FAERS database, spanning the fourth quarter of 2021 to the second quarter of 2024. Signal detection was performed using four statistical methods: the proportional reporting ratio, reporting odds ratio, Bayesian confidence propagation neural network (BCPNN), and multi-item gamma Poisson shrinker. A total of 1372 reports associated with maribavir were identified. Seven significant signals emerged at the system organ class level. At the preferred term level, 76 adverse events (AEs) demonstrated positive signals, including novel events such as pleural effusion, hypersomnia, and anosmia, alongside signals related to ear disorders. The majority of AEs were reported within the first month of maribavir use. This study identified several new adverse event signals for maribavir, offering healthcare professionals a deeper understanding of its safety profile, which may guide safer clinical usage.

Selective G6PDH inactivation for Helicobacter pylori eradication with transformed polysulfide.

Alternative treatment for the highly prevalent Helicobacter pylori infection is imperative due to rising antibiotic resistance. We unexpectedly discovered that the anti-H. pylori component in garlic is hydrogen polysulfide (H2Sn, n⩾2), not organic polysulfides. Studies on the mechanism of action (MoA) show that H2Sn specifically inactivates H. pylori glucose-6-phosphate dehydrogenase (G6PDH) by interfering with electron transfer from glucose-6-phosphate (G6P) to nicotinamide adenine dinucleotide phosphate (NADP+). However, low H2Sn yield makes garlic derivatives hard to be a reliable donor of H2Sn to treat H. pylori infection. To address this challenge, we established a polysulfide transformation process from garlic organosulfur compounds into Fe3S4 that generates H2Sn with a 25-58 times increase in yield. Through chitosan encapsulation, we designed a gastric-adaptive H2Sn microreactor (GAPSR) that eradicates H. pylori with 250 times higher efficiency under gastric conditions. A single GAPSR achieves more rapid H. pylori eradication than combined antibiotics therapy without disturbing the gut microbiota. These findings indicate a distinct MoA transformation mediated by polysulfide as an alternative candidate to treat H. pylori infection.

Emerging Combinatorial Drug Delivery Strategies for Breast Cancer: A Comprehensive Review.

Breast cancer remains the second most prevalent cancer among women in the United States. Despite advancements in surgical, radiological, and chemotherapeutic techniques, multidrug resistance continues to pose significant challenges in effective treatment. Combination chemotherapy has emerged as a promising approach to address these limitations, allowing multiple drugs to target malignancies via distinct mechanisms of action. Increasingly, the use of phytoconstituents alongside chemotherapeutic agents has shown promise in enhancing treatment outcomes. This combination therapy acts on key signaling pathways such as Hedgehog, Notch, Wnt/β- catenin, tyrosine kinases, and phosphatidylinositol 3-kinase (PI3K), which play critical roles in cellular proliferation, apoptosis, angiogenesis, differentiation, invasion, and metastasis. This review explores various signaling pathways involved in breast cancer progression, discusses conventional treatment methods like surgery, adjuvant radiotherapy, hormonal therapy, and chemotherapy, and highlights emerging nanocarrier-based drug delivery systems (DDS). Liposomes, dendrimers, exosomes, polymeric micelles, and nanoparticles (organic, inorganic, gold, magnetic, carbon-based, and quantum dots) are examined as innovative strategies for enhancing drug delivery efficacy. Furthermore, stimuli-responsive DDSs, including reactive oxygen species (ROS), enzyme-, and hypoxia- responsive systems, are presented as cutting-edge approaches to overcoming drug resistance. Special emphasis is placed on the co-delivery of chemotherapeutic agents and plant-based compounds, particularly in estrogen receptor-positive (ER+) breast cancer. This review aims to provide a comprehensive overview of novel combinatorial strategies and advanced nanocarriers for the effective and targeted treatment of breast cancer.

New anti-ovarian cancer quinolone derivatives acting by modulating microRNA processing machinery.

MicroRNAs (miRNAs) play a crucial role in ovarian cancer (OC) pathogenesis and miRNA processing can be the object of pharmacological intervention. By exploiting our in-house quinolone library, we combined a cell-based screening with medicinal chemistry efforts, ultimately leading to derivative 33 with anti-OC activity against distinct cell lines (GI50 values 13.52-31.04 μM) and CC50 Wi-38 = 142.9 μM. Compound 33 retained anticancer activity against additional cancer cells and demonstrated a synergistic effect with cisplatin against cisplatin-resistant A2780 cells. Compound 33 bound TRBP by SPR (K D = 4.09 μM) and thermal shift assays and its activity was TRBP-dependent, leading to modulation of siRNA and miRNA maturation. Derivative 33 exhibited augmented potency against OC cells and a stronger binding affinity for TRBP compared to enoxacin, the sole quinolone identified as a modulator of miRNA maturation. Consequently, 33 represents a promising template for developing novel anti-OC agents with a distinctive mechanism of action.

Asthma Biologics Across the T2 Spectrum of Inflammation in Severe Asthma: Biomarkers and Mechanism of Action.

Airway inflammation, a hallmark feature of asthma, drives many canonical features of the disease, including airflow limitation, mucus plugging, airway remodeling, and hyperresponsiveness. The T2 inflammatory paradigm is firmly established as the dominant mechanism of asthma pathogenesis, largely due to the success of inhaled corticosteroids and biologic therapies targeting components of the T2 pathway, including IL-4, IL-5, IL-13, and thymic stromal lymphopoietin (TSLP). However, up to 30% of patients may lack signatures of meaningful T2 inflammation (ie, T2 low). In T2-low asthma patients, T2 inflammation may be masked due to anti-inflammatory treatments or may be highly variable depending on exposure to common asthma triggers such as allergens, respiratory infections, and smoke or pollution. The epithelium and epithelial cytokines (TSLP, IL-33) are increasingly recognized as upstream drivers of canonical T2 pathways and as modulators of various effector cells, including mast cells, eosinophils, and neutrophils, which impact the pathological manifestations of airway smooth muscle hypertrophy, hypercontractility, and airway hyperresponsiveness. Approved biologics for severe asthma target several distinct mechanisms of action, leading to differential effects on the spectrum of T2 inflammation, inflammatory biomarkers, and treatment efficacy (reducing asthma exacerbations, improving lung function, and diminishing symptoms). The approved anti-asthma biologics primarily target T2 immune pathways, with little evidence suggesting a benefit of targeting non-T2 asthma-associated mediators. Indeed, many negative results challenge current assumptions about the etiology of non-T2 asthma and raise doubts about the viability of targeting popular alternative inflammatory pathways, such as T17. Novel data have emerged from the use of biologics to treat various inflammatory mediators and have furthered our understanding of pathogenic mechanisms that drive asthma. This review discusses inflammatory pathways that contribute to asthma, quantitatively outlines effects of available biologics on biomarkers, and summarizes data and challenges from clinical trials that address non-T2 mechanisms of asthma.

Rescue of Mutant CFTR Channel Activity by Investigational Co-Potentiator Therapy.

Background: The potentiator VX-770 (ivacaftor) has been approved as a monotherapy for over 95 cystic fibrosis (CF)-causing variants associated with gating/conductance defects of the CF transmembrane conductance regulator (CFTR) channel. However, despite its therapeutic success, VX-770 only partially restores CFTR activity for many of these variants, indicating they may benefit from the combination of potentiators exhibiting distinct mechanisms of action (i.e., co-potentiators). We previously identified LSO-24, a hydroxy-1,2,3-triazole-based compound, as a modest potentiator of p.Arg334Trp-CFTR, a variant with a conductance defect for which no modulator therapy is currently approved. Objective/Methods: We synthesized a new set of LSO-24 structure-based compounds, screened their effects on p.Arg334Trp-CFTR activity, and assessed the additivity of hit compounds to VX-770, ABBV-974, ABBV-3067, and apigenin. After validation by electrophysiological assays, the most promising hits were also assessed in cells expressing other variants with defective gating/conductance, namely p.Pro205Ser, p.Ser549Arg, p.Gly551Asp, p.Ser945Leu, and p.Gly1349Asp. Results: We found that five compounds were able to increase p.Arg334Trp-CFTR activity with similar efficacy, but slightly greater potency promoted by LSO-150 and LSO-153 (EC50: 1.01 and 1.26 μM, respectively). These two compounds also displayed a higher rescue of p.Arg334Trp-CFTR activity in combination with VX-770, ABBV-974, and ABBV-3067, but not with apigenin. When tested in cells expressing other CFTR variants, LSO-24 and its derivative LSO-150 increased CFTR activity for the variants p.Ser549Arg, p.Gly551Asp, and p.Ser945Leu with a further effect in combination with VX-770 or ABBV-3067. No potentiator was able to rescue CFTR activity in p.Pro205Ser-expressing cells, while p.Gly1349Asp-CFTR responded to VX-770 and ABBV-3067 but not to LSO-24 or LSO-150. Conclusions: Our data suggest that these new potentiators might share a common mechanism with apigenin, which is conceivably distinct from that of VX-770 and ABBV-3067. The additive rescue of p.Arg334Trp-, p.Ser549Arg-, p.Gly551Asp-, and p.Ser945Leu-CFTR also indicates that these variants could benefit from the development of a co-potentiator therapy.

Neuroprotective Efficacy and Complementary Treatment with Medicinal Herbs: A Comprehensive Review of Recent Therapeutic Approaches in Epilepsy Management.

Central Nervous System (CNS) disorders affect millions of people worldwide, with a significant proportion experiencing drug-resistant forms where conventional medications fail to provide adequate seizure control. This abstract delves into recent advancements and innovative therapies aimed at addressing the complex challenge of CNS-related drug-resistant epilepsy (DRE) management. The idea of precision medicine has opened up new avenues for epilepsy treatment. Herbs such as curcumin, ginkgo biloba, panax ginseng, bacopa monnieri, ashwagandha, and rhodiola rosea influence the BDNF pathway through various mechanisms. These include the activation of CREB, inhibition of NF-κB, modulation of neurotransmitters, reduction of oxidative stress, and anti- inflammatory effects. By promoting BDNF expression and activity, these herbs support neuroplasticity, cognitive function, and overall neuronal health. Novel antiepileptic drugs (AEDs) with distinct mechanisms of action demonstrate efficacy in refractory cases where traditional medications falter. Additionally, repurposing existing drugs for antiepileptic purposes presents a cost-effective strategy to broaden therapeutic choices. Cannabidiol (CBD), derived from cannabis herbs, has garnered attention for its anticonvulsant properties, offering a potential adjunctive therapy for refractory seizures. In conclusion, recent advances and innovative therapies represent a multifaceted approach to managing drug-resistant epilepsy. Leveraging precision medicine, neurostimulation technologies, novel pharmaceuticals, and complementary therapies, clinicians can optimize treatment outcomes and improve the life expectancy of patients living with refractory seizures. Genetic testing and biomarker identification now allow for personalized therapeutic approaches tailored to individual patient profiles. Utilizing next-generation sequencing techniques, researchers have elucidated genetic mutations.

From Atrial Small-conductance Calcium-activated Potassium Channels to New Antiarrhythmics.

Despite significant advances in its management, AF remains a major healthcare burden affecting millions of individuals. Rhythm control with antiarrhythmic drugs or catheter ablation has been shown to improve symptoms and outcomes in AF patients, but current treatment options have limited efficacy and/or significant side-effects. Novel mechanism-based approaches could potentially be more effective, enabling improved therapeutic strategies for managing AF. Small-conductance calcium-activated potassium (SK or KCa2.x) channels encoded by KCNN1-3 have recently gathered interest as novel antiarrhythmic targets with potential atrial-predominant effects. Here, the molecular composition of smallconductance calcium-activated potassium channels and their complex regulation in AF as the basis for understanding the distinct mechanism of action of pore-blockers (apamin, UCL1684, ICAGEN) and modulators of calcium-dependent activation (NS8593, AP14145, AP30663) are summarised. Furthermore, the preclinical and early clinical evidence for the role of small-conductance calcium-activated potassium channel inhibitors in the treatment of AF are reviewed.

Targeting Refractory Triple-Negative Breast Cancer with Sacituzumab Govitecan: A New Era in Precision Medicine.

Advanced triple-negative breast cancer (TNBC) has poorer outcomes due to its aggressive behavior and restricted therapeutic options. While therapies like checkpoint inhibitors and PARP inhibitors offer some benefits, chemotherapy remains ineffective beyond the first line of treatment. Antibody-drug conjugates (ADCs) like sacituzumab govitecan-hziy (SG) represent a significant advancement. SG combines SN-38, an irinotecan derivative, with a Trop-2-targeting antibody via a pH-sensitive linking moiety, achieving a good drug:antibody ratio. In a phase I-II study involving metastatic TNBC (mTNBC) individuals, SG achieved an overall response rate of 33.3% and a median response period of 7.7 months. The phase III ASCENT trial demonstrated SG's efficacy in relapsed or refractory TNBC, improving median progression-free survival and median overall survival compared to chemotherapy. Common side effects include neutropenia, nausea, and fatigue. This article highlights the clinical potential, pharmacokinetics, safety profile, and resistance mechanisms of SG along with key ongoing clinical trials, emphasizing its role in managing refractory mTNBC, especially in third-line therapy. The review also discusses current strategies for managing adverse reactions and sequencing ADC treatments in clinical practice, along with the predicted basis of resistance. The optimal sequencing of SG relative to other ADCs, such as trastuzumab deruxtecan or T-DXd, remains an evolving question, especially as newer agents with distinct mechanisms of action and safety profiles enter the field. Further research is essential to establish evidence-based strategies for sequencing SG and addressing disease progression post-ADC therapy.

Mechanistic Insights into the Adenosine A1 Receptor’s Positive Allosteric Modulation for Non-Opioid Analgesics

The adenosine A1 receptor (A1R) is a promising target for pain treatment. However, the development of therapeutic agonists is hampered by adverse effects, mainly including sedation, bradycardia, hypotension, or respiratory depression. Recently discovered molecules able to overcome this impediment are the positive allosteric modulator MIPS521 and the A1R-selective agonist BnOCPA, which are both potent and powerful analgesics with fewer side effects. While BnOCPA directly activates the A1R from the canonical orthosteric site, MIPS521 binds to an allosteric site, acting in concert with orthosteric adenosine and tuning its pharmacology. Given their overlapping profile in pain models but distinct mechanisms of action, we combined pharmacology and microsecond molecular dynamics simulations to address MIPS521 and BnOCPA activity and their reciprocal influence when bound to the A1R. We show that MIPS521 changes adenosine and BnOCPA G protein selectivity in opposite ways and propose a structural model where TM7 dynamics are differently affected and involved in the G protein preferences of adenosine and BnOCPA.

Hapalindole Q suppresses autophagosome−lysosome fusion by promoting YAP1 degradation via chaperon-mediated autophagy

Autophagy is a conserved catabolic process crucial for maintaining cellular homeostasis and has emerged as a promising therapeutic target for many diseases. Mechanistically novel small-molecule autophagy regulators are highly desirable from a pharmacological point of view. Here, we report the macroautophagy-inhibitory effect of hapalindole Q, a member of the structurally intriguing but biologically understudied hapalindole family of indole terpenoids. This compound promotes the noncanonical degradation of Yes-associated protein 1 (YAP1), the downstream effector of the Hippo signaling pathway, via chaperone-mediated autophagy, disrupting proper distribution of Rab7 and suppressing autophagosome-lysosome fusion in macroautophagy. Its binding to YAP1 is further confirmed by using biophysical techniques. A preliminary structure-activity relationship study reveals that the hapalindole Q scaffold, rather than the isothiocyanate group, is essential for YAP1 binding and degradation. This work not only identifies a macroautophagy inhibitor with a distinct mechanism of action but also provided a molecular scaffold for direct targeting of YAP1, which may benefit the development of therapeutics for both autophagy-related and Hippo-YAP-related diseases.

Trehalose: Neuroprotective Effects and Mechanisms-An Updated Review.

Trehalose is a naturally occurring disaccharide that has recently gained significant attention for its neuroprotective properties in various models of neurodegeneration. This review provides an overview of available experimental data on the beneficial properties of trehalose for central nervous system pathological conditions. Trehalose's impact on neuronal cell survival and function was also examined. As a result, we identified that trehalose's neuroprotection includes autophagy modulation as well as its capability to stabilize proteins and inhibit the formation of misfolded ones. Moreover, trehalose mitigates oxidative stress-induced neuronal damage by stabilizing cellular membranes and modulating mitochondrial function. Furthermore, trehalose attenuates excitotoxicity-induced neuroinflammation by suppressing pro-inflammatory cytokine release and inhibiting inflammasome activation. A possible connection of trehalose with the gut-brain axis was also examined. These findings highlight the potential therapeutic effects of trehalose in neurodegenerative diseases. According to the conclusions drawn from this study, trehalose is a promising neuroprotective agent as a result of its distinct mechanism of action, which makes this compound a candidate for further research and the development of therapeutic strategies to combat neuronal damage and promote neuroprotection in various neurological diseases.