Therapeutic Failure Research Articles

Epigenetic Activation of the CMTM6-IGF2BP1-EP300 Positive Feedback Loop Drives Gemcitabine Resistance in Pancreatic Ductal Adenocarcinoma.

Pancreatic ductal adenocarcinoma (PDAC) is a highly malignant tumor with a dismal prognosis. Gemcitabine-based chemotherapy has emerged as a first-line treatment for PDAC. However, the development of gemcitabine resistance often results in therapeutic failure. In order to uncover the underlying mechanisms of gemcitabine resistance, gemcitabine-resistant PDAC cell lines and patient-derived xenograft (PDX) models are established and subjected to RNA sequencing. It is found that CMTM6 is closely related to gemcitabine resistance in PDAC. Multi-omics analysis revealed that EP300-mediated H3K27ac modification is involved in the transcriptional activation of CMTM6, which maintains IGF2BP1 expression by preventing its ubiquitination. The m6A reader IGF2BP1 stabilizes the EP300 and MYC mRNAs by recognizing m6A modifications, forming a positive feedback loop that enhances tumor stemness and ultimately contributes to PDAC resistance. The combined application of the EP300 inhibitor inobrodib and gemcitabine exerts a synergistic effect on PDAC. Overall, these findings reveal that the EP300-CMTM6-IGF2BP1 positive feedback loop facilitates gemcitabine resistance via epigenetic reprogramming and the combined use of inobrodib and gemcitabine represents a promising strategy for overcoming chemoresistance in PDAC, warranting further investigation in clinical trials.

Nanostructured Lipid Carrier for Dermatological Application: A Comprehensive Review and Future Perspective

Abstract:: Dermatological disease states have psychological impacts that affect a patient’s life. In the management of such disorders, topical delivery has an important role. However, the conven-tional topical delivery systems suffer from various limitations, like skin irritation, a minute quan-tity of drugs reaching disease sites, and over and under medication, which leads to an adverse re-action and therapeutic failure, respectively. Therefore, researchers continuously search for an al-ternate delivery system for treating skin disease. In recent years, nanostructured lipid carriers (NLC) have emanated as promising carrier systems for topical delivery. The current review pro-vides an in-depth insight into topical administration for treating a variety of dermatological issues using NLCs as a carrier. This review highlights the suitability of NLCs as carriers for topical de-livery, their method of preparation, and their characterization. In the present review, the main emphasis has been given to the management of various dermatological problems by using NLCs as a carrier; a plethora of literature investigating NLC as the carrier for topical delivery has been included in this review. In this paper, an attempt has been made to provide a summary of the re-search carried out in this field that will encourage further research in this arena.

Targeted nanomedicine for reprogramming the tumor innate immune system: From bench to bedside

Tumor-associated innate immune cells such as tumor-associated macrophages, neutrophils, dendritic cells play a crucial role in tumor progression, angiogenesis and metastasis. These cells also control the efficacy of chemotherapy and immunotherapy by inducing drug resistance and immunosuppression, leading to therapeutic failures. Therefore, targeting the tumor-associated innate immune cells has gained high attention for the development of effective cancer therapy. Nanomedicine based strategies to target these cells are highly relevant and can be used to reprogram these cells. In this review, we discuss the fundamental roles of the tumor-associated innate immune cells in the tumor microenvironment and different strategies to modulate them. Then, nanomedicine-based strategies to target different tumor innate immune cells are explained in detail. While the clinical development of the targeted nanomedicine remains a great challenge in practice, we have provided our perspectives on various factors such as pharmaceutical aspects, preclinical testing and biological aspects which are crucial to consider before translating these targeting strategies to clinics.

A natural killer cell mimic against intracellular pathogen infections.

In the competition between the pathogen infection and the host defense, infectious microorganisms may enter the host cells by evading host defense mechanisms and use the intracellular biomolecules as replication nutrient. Among them, intracellular Staphylococcus aureus relies on the host cells to protect itself from the attacks by antibiotics or immune system to achieve long-term colonization in the host, and the consequent clinical therapeutic failures and relapses after antibiotic treatment. Here, we demonstrate that intracellular S. aureus surviving well even in the presence of vancomycin can be effectively eliminated using an emerging cell-mimicking therapeutic strategy. These cell mimics with natural killer cell-like activity (NKMs) are composed of a redox-responsive degradable carrier, and perforin and granzyme B within the carrier. NKMs perform far more effectivly than clinical antibiotics in treating intracellular bacterial infections, providing a direct evidence of the NK cell-mimicking immune mechanism in the treatment of intracellular S. aureus.

Current antibiotic resistance of Enterobacteriaceae isolated at Avicenna military hospital of Marrakesh

Enterobacteriaceae are bacteria found in the digestive system, known for causing infections and displaying antibiotic resistance. The World Health Organization (WHO) identifies strains resistant to third-generation cephalosporins and carbapenems as priority pathogens. This study, conducted at Avicenne Military Hospital of Marrakech, aimed to assess the epidemiological and antibiotic resistance profiles of Enterobacteriaceae over a two-year period (May 2020 - April 2022) to inform updated antibiotic use recommendations. This retrospective study analyzed 1,626 positive bacterial isolates from various hospital departments, including medical, surgical, intensive care, emergency units, and external samples. Of these, 1,163 (71.5%) were Enterobacteriaceae, predominantly Escherichia coli, Klebsiella pneumoniae, and Enterobacter cloacae, primarily isolated from urine, pus, and blood cultures. Antibiotic resistance was assessed, revealing that 614 (52.8%) of Enterobacteriaceae were extended-spectrum beta-lactamase producers (ESBL-E), and 115 (9.9%) were carbapenemase-producing Enterobacteriaceae (CPE). The study’s findings align with existing literature, showing a higher prevalence of Enterobacteriaceae in males and frequent isolation of Escherichia coli. The rise in multidrug-resistant Enterobacteriaceae, particularly ESBL-E and CPE, poses risks such as therapeutic failure, increased morbidity and mortality, and significant economic impacts. To address this, the study emphasizes the importance of early detection, infection control measures, responsible antibiotic prescribing, and collaborative efforts across hospital departments to reduce the spread of resistant strains.

Understanding Voriconazole Metabolism: A Middle-Out Physiologically-Based Pharmacokinetic Modelling Framework Integrating In Vitro and Clinical Insights.

Voriconazole (VRC), a broad-spectrum antifungal drug, exhibits nonlinear pharmacokinetics (PK) due to saturable metabolic processes, autoinhibition and metabolite-mediated inhibition on their own formation. VRC PK is also characterised by high inter- and intraindividual variability, primarily associated with cytochrome P450 (CYP)2C19 genetic polymorphism. Additionally, recent in vitro findings indicate that VRC main metabolites, voriconazole N-oxide (NO) and hydroxyvoriconazole (OHVRC), inhibit CYP enzymes responsible for VRC metabolism, adding to its PK variability. This variability poses a significant risk of therapeutic failure or adverse events, which are major challenges in VRC therapy. Understanding the underlying processes and sources of these variabilities is essentialfor safe and effective therapy. This work aimed to develop a whole-body physiologically-based pharmacokinetic (PBPK) modelling framework that elucidates the complex metabolism of VRC and the impact of its metabolites, NO and OHVRC, on the PK of the parent, leveraging both in vitro and in vivo clinical data in a middle-out approach. A coupled parent-metabolite PBPK model for VRC, NO and OHVRC was developed in a stepwise manner using PK-Sim® and MoBi®. Based on available in vitro data, NO formation was assumed to be mediated by CYP2C19, CYP3A4, and CYP2C9, while OHVRC formation was attributed solely to CYP3A4. Both metabolites were assumed to be excreted via renal clearance, with hepatic elimination also considered for NO. Inhibition functions were implemented to describe the complex interaction network of VRC autoinhibition and metabolite-mediated inhibition on each CYP enzyme. Using a combined bottom-up and middle-out approach, incorporating data from multiple clinical studies and existing literature, the model accurately predicted plasma concentration-time profiles across various intravenous dosing regimens in healthy adults, of different CYP2C19 genotype-predicted phenotypes. All (100%) of the predicted area under the concentration-time curve (AUC) and 94% of maximum concentration (Cmax) values of VRC met the 1.25-fold acceptance criterion, with overall absolute average fold errors of 1.12 and 1.14, respectively. Furthermore, all predicted AUC and Cmax values of NO and OHVRC met the twofold acceptance criterion. This comprehensive parent-metabolite PBPK model of VRC quantitatively elucidated the complex metabolism of the drug and emphasised the substantial impact of the primary metabolites on VRC PK. The comprehensive approachcombining bottom-up and middle-out modelling, therebyaccounting for VRC autoinhibition, metabolite-mediated inhibition, and the impact of CYP2C19 genetic polymorphisms, enhances our understanding of VRC PK. Moreover, the model can be pivotal in designing further in vitro experiments, ultimately allowing for extrapolation to paediatric populations, enhance treatment individualisation and improve clinical outcomes.

Reduced vancomycin susceptibility in Staphylococcus aureus clinical isolates: a spectrum of less investigated uncertainties

BackgroundStaphylococcus aureus clinical isolates with vancomycin MICs of 2 µg/ml have been associated with vancomycin therapeutic failure and the heterogenous vancomycin-intermediate S. aureus (hVISA) phenotype. While carriage of van genes has usually been associated with higher level of MIC and frank vancomycin resistance, the unrecognized risk of hetero-resistance is frequently underestimated. Methods used for assessing vancomycin susceptibility have also shown different concordance and variable performance and accessibility in routine clinical diagnostics posing a challenge to inform treatment selection in hospital settings.MethodsA total of 195 clinical samples were obtained among which 100 S. aureus isolates were identified. Ninety-six MRSA isolates have been identified using cefoxitin disc and mecA gene detection. The vanA and vanB genes have been screened for in the studied isolates using conventional PCR amplification. Examination of reduced vancomycin susceptibility has been performed using vancomycin screen agar, Broth Micro Dilution method (BMD), and VITEK2. Blood isolates were screened for hVISA using PAP-AUC method.ResultsVancomycin screening agar applied to 96 MRSA isolates revealed 16 isolates with reduced vancomycin susceptibility. Further MIC testing revealed that 7 isolates were VISA and only 1 isolate was identified as VRSA using both BMD MIC method and VITEK2. Among 24 tested blood isolates, 4 isolates (16.7%) revealed the hVISA phenotype as identified using PAP-AUC method. Using PCR, vanA gene was identified in 5 S. aureus isolates (5%). Three of them were VSSA while the other two isolates were VISA.ConclusionIn this study, we report the very low prevalence of VRSA among the tested S. aureus clinical isolates (1%) and the existence of hVISA phenotype among studied S. aureus blood isolates at the rate of 16.7% in our setting. Fifty percent (8/16) of isolates that demonstrated reduced vancomycin susceptibility using vancomycin agar screen tested susceptible using both broth dilution method and VITEK2. These finding together with the concerning silent carriage of vanA gene among VSSA and VISA (5%) may underly hidden and uninvestigated factors contributing to vancomycin treatment failure that warrant cautious vancomycin prescription.

Persistence of Helicobacter Pylori Coccoid Forms in Different Environments

Objective: The present study aims to determine the possibility of H. pylori coccoid forms to survive in our surrounding environments, thus exhibiting public health hazard. Method: Helicobacter pylori strain Makkah 7 accession number HQ622108, was inoculated in samples of soil, well, tap, swimming pool, and sewage water; in which, an average initial inoculum of 107 CFU/ml was inoculated. The experiment was conducted, outdoor where ambient temperature varied between 39-55°C in Jeddah city, Saudi Arabia. The survival rate of H. pylori strain was quantitatively and qualitatively studied for five months. Results: Viable counts were undetectable after 24 hours, while total count varied between 107 to 106, and declined to 103 bacterial cell/ml five months later. Interestingly, microscopic examination revealed few non-motile rods and motile coccoid forms. All samples were removed and placed at 4°C for one month. Following, total count, morphology, and motility were examined, showing motile coccoid forms. Electron microscopic and, molecular studies were carried out, confirming that the species is H. pylori, which was detected by using 16S rRNA primer for H. pylori with a product size of 163 bp. The ability of H. pylori strain to persist and survive, by being motile in the coccoid form, for five months under such hostile environment, strongly indicates that the coccoid form plays a vital role in the transmission, recrudescence, and therapeutic failure. It is indeed a hazardous and a crucial infectious phase of this bacterium. Conclusion: Detecting coccoid forms in water and soil, accompanied by their eradication, must be seriously considered and applied. Consequently, hindering and preventing different diseases caused by H. pylori.

Computer-Aided Identification and Design of Ligands for Multi-Targeting Inhibition of a Molecular Acute Myeloid Leukemia Network

Background/Objectives: Acute myeloid leukemia (AML) is characterized by therapeutic failure and long-term risk for disease relapses. As several therapeutic targets participate in networks, they can rewire to eventually evade single-target drugs. Hence, multi-targeting approaches are considered on the expectation that interference with many different components could synergistically hinder activation of alternative pathways and demolish the network one-off, leading to complete disease remission. Methods: Herein, we established a network-based, computer-aided approach for the rational design of drug combinations and de novo agents that interact with many AML network components simultaneously. Results: A reconstructed AML network guided the selection of suitable protein hubs and corresponding multi-targeting strategies. For proteins responsive to existing drugs, a greedy algorithm identified the minimum amount of compounds targeting the maximum number of hubs. We predicted permissible combinations of amiodarone, artenimol, fostamatinib, ponatinib, procaine, and vismodegib that interfere with 3–8 hubs, and we elucidated the pharmacological mode of action of procaine on DNMT3A. For proteins that do not respond to any approved drugs, namely cyclins A1, D2, and E1, we used structure-based de novo drug design to generate a novel triple-targeting compound of the chemical formula C15H15NO5, with favorable pharmacological and drug-like properties. Conclusions: Overall, by integrating network and structural pharmacology with molecular modeling, we determined two complementary strategies with the potential to annihilate the AML network, one in the form of repurposable drug combinations and the other as a de novo synthesized triple-targeting agent. These target–drug interactions could be prioritized for preclinical and clinical testing toward precision medicine for AML.

Subclinical hypothyroidism and plasma levels of commonly prescribed anti-seizure medications

Background: Epilepsy remains the most common neurological problem worldwide. Most commonly prescribed antiseizure medications (ASMs) like phenytoin, sodium valproate, and carbamazepine show high inter-individual variability in bioavailability due to genetic and epigenetic factors resulting in either therapeutic failure or toxicity. In our study, we aim to determine the association between subclinical hypothyroidism and the plasma levels of these commonly prescribed ASMs, leading to either therapeutic failure or adverse drug reactions. Methods: We collected demographic data, details about the antiepileptic medication, and plasma levels of ASMs (phenytoin, carbamazepine, and sodium valproate) from patients on antiseizure medications who came for routine therapeutic drug monitoring (TDM). High-performance liquid chromatography (HPLC) estimated plasma levels of the antiseizure medications as per the TDM laboratory standard operating procedure (SOP) and thyroid function test (TSH) by a standard enzyme-linked immune-sorbent assay (ELISA) kit. Results: Of the 158 patients who had TDM, 75.31% were taking sodium valproate, 15.18% were on phenytoin, and 9.49% were on carbamazepine monotherapy. In our study, we found that 12 patients (7.59%) had TSH levels between 4 to 10 mIU/l, indicating subclinical hypothyroidism (SCH). The plasma drug levels of all 12 patients who had SCH were found to be below the therapeutic range. Conclusions: This study has established a significant association between ASMs, particularly sodium valproate, and thyroid dysfunction, specifically SCH, in patients with epilepsy. Our findings suggest that prolonged ASM therapy can lead to thyroid disturbances, warranting careful monitoring of thyroid function in these patients.

Recent Updates in Nanocrystal Technology: A Reference to Oral Drug Delivery System

Increasing the oral bioavailability of drugs that dissolve slowly may be possible with the use of nanocrystal technology. It is being employed for drug engineering and research after making rapid advancements in recent years. The manufacturing process for pharmaceuticals is significantly hampered by the low solubility and quick rate of dissolution of poorly soluble medications. When taken orally, medications that are poorly soluble often have low and inconsistent bioavailability, which could lead to therapeutic failure. Pure drug nanocrystals prepared via "bottom-up" or "topdown" procedu are able to significantly improve the way poorly soluble medications dissolve thanks to their enormous surface area, which in turn enhances oral absorption. Nanocrystal medications allow for the creation of various dosage formulations. The use of nanocrystal technology in pharmaceutical research, particularly for oral drug delivery systems, is the main focus of this review. First, a quick discussion on the characteristics of pharmaceutical nanocrystals and several nanocrystal technology preparation techniques is provided. The application of nanocrystal technology in pharmaceutical science is covered after a discussion of the creation of prolonged-release formulations. Next follows a brief overview of the scaling-up procedure, commercial nanocrystal drug products, and regulatory aspects of nanodrugs. This paper offers a thorough explanation of preparation techniques, their characterisation, and how they are used in oral drug delivery systems.

Whole-genome sequencing of toxigenic Clostridioides difficile reveals multidrug resistance and virulence genes in strains of environmental and animal origin

BackgroundClostridioides difficile has been recognized as an emerging pathogen in both humans and animals. In this context, antimicrobial resistance plays a major role in driving the spread of this disease, often leading to therapeutic failure. Moreover, recent increases in community-acquired C. difficile infections have led to greater numbers of investigations into the animal origin of the disease. The aim of this study was to evaluate the genetic similarities between 23 environmental and animal isolates by using whole-genome sequencing and to determine antimicrobial resistance and virulence factor genes in toxigenic C. difficile strains to provide important data for the development of diagnostic methods or treatment guidelines.ResultsThe most common sequence type was ST11 (87%), followed by ST2 (9%) and ST19 (4%). In addition, 86.95% of the strains exhibited multidrug resistance, with antimicrobial resistance to mainly aminoglycosides, fluoroquinolones, tetracycline and B-lactams; nevertheless, one strain also carried other resistance genes that conferred resistance to lincosamide, macrolides, streptogramin a, streptogramin b, pleuromutilin, oxazolidinone and amphenicol. In addition, a wide range of virulence factor genes, such as those encoding adherence factors, exoenzymes and toxins, were found. However, we observed variations between toxinotypes, ribotypes and sequence types.ConclusionsThe results of this study demonstrated significant genetic similarity between ST11 strains isolated from environmental sampling and from animal origin; these strains may represent a reservoir for community-acquired C. difficile infection, which is becoming a growing public health threat due to the development of multridug resistant (MDR) bacteria and the number of virulence factors detected.

AI-powered Solutions for Casualty Assessment in Drug Safety and Patient Care

Objective: An adverse drug reaction is defined as “an appreciably harmful or unpleasant reaction, resulting from an intervention related to the use of a medicinal product, which warrants prevention or specific treatment, alteration of the dosage regimen, or withdrawal of the product, as it predicts hazard from future administration.” Methodology: Currently used to report such responses, the International Classification of Diseases will soon incorporate WHO's Adverse Reaction Terminology. A medication's bad effects can fall into one of six types, each having its own mnemonic: withdrawal, therapeutic failure, dose-and time-related, non-dose-related, weird, increased withdrawal, and withdrawal overall (time-related). Factors such as timing, illness pattern, investigation findings, and retesting the medicine could be useful in pinpointing the reason for a suspected adverse drug reaction. Management includes treating the effects of the medication specifically as well as, if feasible, stopping it altogether. Results: Reporting suspected adverse medication reactions is important. Monitoring techniques are able to identify responses and establish connections. There is many software that is used to report and monitor adverse drug reaction responses. Various Pharmacovigilance companies use AI technology to utilize this method to record signals, communicate, and solve new issues in order to limit or avoid harm because of large data size.

The dual role of autophagy in suppressing and promoting hepatocellular carcinoma.

The 5-year survival rate for hepatocellular carcinoma (HCC), a deadly form of liver cancer, is quite low. Although drug therapy is successful, patients with advanced liver cancer frequently develop resistance because of the significant phenotypic and genetic heterogeneity of these cells. The overexpression of drug efflux transporters, downstream adaptive responses, malfunctioning DNA damage repair, epigenetic modification, the tumor microenvironment, and the extracellular matrix can all be linked to drug resistance. The evolutionary process of autophagy, which is in charge of intracellular breakdown, is intimately linked to medication resistance in HCC. Autophagy is involved in both the promotion and suppression of cancer by influencing treatment resistance, metastasis, carcinogenesis, and the viability of stem cells. Certain autophagy regulators are employed in anticancer treatment; however, because of the dual functions of autophagy, their use is restricted, and therapeutic failure is increased. By focusing on autophagy, it is possible to reduce HCC expansion and metastasis, and enhance tumor cell reactivity to treatment. Macroautophagy, the best-characterized type of autophagy, involves the formation of a sequestering compartment termed a phagophore, which surrounds and encloses aberrant or superfluous components. The phagophore matures into a double-membrane autophagosome that delivers the cargo to the lysosome; lysosomes and autophagosomes fuse to degrade and recycle the cargo. Macroautophagy plays dual functions in both promoting and suppressing cancer in a variety of cancer types.

Cytomegalovirus infection in transplant patients according to pre-transplant risk in a Hospital in Northeastern Mexico

Abstract Background Cytomegalovirus (CMV) is an important cause of morbidity and mortality in patients who receive a hematopoietic stem cell transplant (HSCT). It is possible to stratify the risk of developing the disease due to this agent according to the serological status of the HSCT donor and recipient. In post-transplant patients, significant T lymphocyte dysfunction occurs, so reactivation of CMV is common, which is why it should be monitored after HSCT. Our objective is to determine the association of CMV infection in post-transplant patients according to pre-transplant risk status. Methods Patients who received HSCT from January 2019 to June 2023 were included, they were classified according to their pre-transplant risk status and CMV infection was diagnosed by performing a viral load on day 30. Results 70 patients with hemato-oncological diseases who received an HSCT were included, a median age of 9 years (0-16) was found, predominance of the male sex (60%), the most frequent type of transplant was haploidentical (82.9 %). Of these, 20 (28.5%) had CMV infection, with pre-transplant risk status mostly high risk (85%), of the low-risk patients (25.7%) 10% had the infection and the very high risk (4.3%) only 5% were reported infected. The period during which the infection occurred most frequently was in the early post-pregnancy stage (66.6%) and the majority received treatment with valganciclovir (95%). Of the patients infected with CMV, 15 (75%) were asymptomatic, and 5 (25%) had associated symptoms, with 2 (10%) presenting with urinary symptoms (dysuria, frequency, suprapubic pain, tenesmus), and 2 (10%) with fever, and 1 hematochezia (5%). Regarding clinical outcomes, 17 patients (85%) presented resolution of the disease, 1 (5%) presented therapeutic failure and 1 (5%) died due to multiple organ failure. Conclusion Due to the high prevalence of CMV infection, it is important to maintain a high index of suspicion of this pathology in this population, with the aim of achieving early diagnosis and timely initiation of treatment.

Tumor-associated macrophages/C-X-C motif chemokine ligand 1 promotes breast cancer autophagy-mediated chemoresistance via IGF1R/STAT3/HMGB1 signaling

Autophagy-mediated chemoresistance is the core mechanism for therapeutic failure and poor prognosis in breast cancer. Breast cancer chemotherapy resistance is believed to be influenced by tumor-associated macrophages (TAMs), by which C-X-C motif chemokine ligand 1 (CXCL1) is the most abundant cytokine secreted. Yet, its role in mediating autophagy-related chemoresistance is still unknown. This study aimed to explore the molecular mechanisms by which TAMs/CXCL1 induced autophagy-mediated chemoresistance in breast cancer. It was found that TAMs/CXCL1 promoted chemoresistance of breast cancer cells through autophagy activation in vitro, and CXCL1 silence could enhance the chemosensitivity of paclitaxel-resistant breast cancer cells via autophagy inhibition. A high-throughput quantitative PCR chip and subsequent target validation showed that CXCL1 induced autophagy-mediated chemoresistance by inhibiting VHL-mediated IGF1R ubiquitination. The elevated IGF1R then promoted STAT3/HMGB1 signaling to facilitate autophagy. Additionally, TAMs/CXCL1 silence improved paclitaxel chemosensitivity by suppressing autophagy in breast cancer mice xenografts, and clinical studies further linked CXCL1 to IGF1R/HMGB1 signaling, as well as shorter free survival of recurrence. Taken together, these results not only uncover the crucial role of TAMs/CXCL1 signaling in mediating breast cancer chemoresistance through enhancing autophagy, but also shed novel light on the molecular mechanism of IGF1R/STAT3/HMGB1 pathway in regulating autophagy and its impact on cancer prognosis.

MCL1 inhibitor S63845 delivered by follicle-stimulating hormone modified liposome potentiates carboplatin efficacy in ovarian cancer

Platinum resistance cause therapeutic failure and poor prognosis in ovarian cancer, and evasion of apoptosis is a critical factor in chemoresistance. A limited number of FDA-approved anticancer drugs directly target apoptotic pathways. Here, we discovered that MCL1, a critical anti-apoptotic protein, is amplified and associated with platinum resistance and survival in ovarian cancer, assisting in personalized treatment. We further identified S63845 through drug-based screening, the most potent MCL1 inhibitor, which efficiently enhanced carboplatin (CBP) sensitivity in various ovarian cancer models, including primary ovarian cancer cells, orthotopic ovarian cancer, peritoneal metastasis, and human patient-derived xenograft (PDX) models. Mechanistically, S63845 competitively binds to MCL1, disrupts the binding of apoptosis effector (BAK and BAX) or pro-apoptotic BH3 protein (BIM) to MCL1 respectively, and eventually enhances CBP-induced apoptosis.To promote the clinical transformation of S63845, we developed follicle-stimulating hormone-modified liposome nanoparticles (S63845@Lipo-FSH) to enhance stability, membrane penetration, and tumor-targeting capabilities. S63845@Lipo-FSH exhibits a superior therapeutic efficacy and tumor targeting compared to free S63845, even when the dose of S63845 is reduced to one-fifth. Overall, targeting MCL1 by S63845@Lipo-FSH enhances CBP efficiency in ovarian cancer, with safety and efficacy, suggesting that this strategy is effective and promising for clinical application.

Listeria grayi Meningitis in a Polypathological Patient: A Case Report

Background: The various species of the Listeria genus are frequently isolated from food and drink products. They are classified into two categories according to their pathogenicity. Pathogenic species are frequently incriminated in infections of the elderly, immunocompromised and pregnant women. The Listeria grayi species is rarely isolated as a pathogen in human pathologies. We report a case of L. grayi meningitis in a polypathological patient. Antimicrobial susceptibility testing revealed resistance to ampicillin and susceptibility to Meropenem. Therapeutic failure was recorded despite in vitro sensitivity Methods: Conventional biochemical test and Api Listeria gallery was used for identification of the isolate. Results: We report a case of L. grayi meningitis in a polypathological patient. Antimicrobial susceptibility testing revealed resistance to ampicillin and susceptibility to Meropenem. Therapeutic failure was recorded despite in vitro sensitivity. Conclusion: Given its infrequent reporting, Listeria grayi meningitis warrants consideration, especially in elderly patients with multiple pathologies.

S2322 Factors Associated With Therapeutic Failure in the Eradication of Helicobacter pylori in a Population in Northeast Colombia

S2322 Factors Associated With Therapeutic Failure in the Eradication of Helicobacter pylori in a Population in Northeast Colombia

Computational Exploration of Limonin as a Potential Inhibitor of DapB in Klebsiella pneumoniae.

Klebsiella pneumoniae has emerged as a significant multidrug-resistant pathogen, classified as a critical priority by the World Health Organization. The rising rates of antibiotic resistance have led to increased therapeutic failures, diminishing the effectiveness of existing antibiotics. Consequently, there is an urgent need for alternative treatments to effectively inhibit the growth of K. pneumoniae and mitigate associated diseases. Phytochemicals have demonstrated potential advantages over traditional antibiotics, prompting their exploration as innovative therapeutic agents. This study aimed to identify phytochemicals that can inhibit dapB, a vital enzyme in the lysine biosynthesis pathway of K. pneumoniae, which is essential for protein synthesis and the cross-linking of the bacterial peptidoglycan cell wall. We screened 17,934 phytochemicals based on Lipinski's Rule of Five, along with their Absorption, Distribution, Metabolism, Excretion properties and toxicological parameters. Next, we conducted triplicate docking studies against dapB to evaluate the library further. The most promising molecules then underwent 100 ns Molecular Dynamics simulations in triplicate, followed by binding free energy calculations to identify potential dapB inhibitors. This in silico analysis highlighted limonin as a promising inhibitor of dapB in K. pneumoniae. Further experimental validation is crucial to enhance limonin's potential as a novel therapeutic agent against K. pneumoniae-associated diseases.