Search Results (459)

Polydopamine (PDA) surface coatings are widely used in biomedical engineering to enhance cell–substrate interactions; however, their effects on cancer-cell behavior remain unclear. In this study, we investigated how PDA-coated two-dimensional (2D) culture surfaces influence oncogenic traits of human prostate cancer (PC) cells in vitro. Using LNCaP, DU145, and PC3 cell lines, we found that PDA-coated substrates markedly increased the adhesion, migration, invasion, proliferation, and colony formation in a dose- and time-dependent manner. PDA exposure also induced epithelial–mesenchymal transition (EMT), upregulated cancer stem cell markers (CD44, CD117, CD133, Sox2, Oct4, and Nanog), and elevated expression of metastasis- and chemoresistance-associated molecules (MMP-2, MMP-9, MDR1, and MRP1). Mechanistically, PDA coatings enhanced integrin α₂β₁-associated cell adhesion, accompanied by increased focal adhesion kinase (FAK) phosphorylation and downstream activation of JNK signaling. Pharmacological inhibition of integrin α₂β₁ (BTT-3033), FAK (PF573228) and JNK (SP600125) effectively abrogated PDA-induced malignant phenotypes and restored chemosensitivity to cabazitaxel, cisplatin, docetaxel, curcumin, and enzalutamide. Collectively, these findings identify PDA-coated surfaces as a simple, efficient, and reductionist in vitro platform for studying adhesion-mediated signaling and phenotypic plasticity in PC cells, while acknowledging that further validation in three-dimensional (3D) and patient-derived models will be required to establish in vivo relevance. Full article

Background: Chromobacterium violaceum is an emerging multidrug-resistant (MDR) Gram-negative bacterium associated with severe septicemia, abscess formation, and high mortality, particularly in immunocompromised individuals. Increasing antimicrobial resistance and the absence of approved vaccines underscore the urgent need for alternative preventive strategies. Traditional vaccine approaches are often inadequate against genetically diverse MDR pathogens, prompting the use of computational immunology and reverse vaccinology for vaccine design. Objectives: This study aimed to design and characterize a novel multi-epitope subunit vaccine (MEV) candidate against C. violaceum using a comprehensive pangenome-guided subtractive proteomics and immunoinformatics pipeline to identify conserved antigenic targets capable of eliciting strong immune responses. Methods: Comparative genomic analysis across eight C. violaceum strains identified 3144 core genes. Subtractive proteomics filtering yielded two essential, non-homologous, surface-accessible, and antigenic proteins—penicillin-binding protein 1A (Pbp1A) and organic solvent tolerance protein (LptD)—as vaccine targets. Cytotoxic T-lymphocyte (CTL), helper T-lymphocyte (HTL), and B-cell epitopes were predicted and integrated into a 272-amino-acid MEV construct adjuvanted with human β-defensin-4A using optimal linkers. The construct was evaluated through structural modeling, molecular docking with TLR4, molecular dynamics simulation, immune simulation, and in silico cloning into the pET-28a(+) vector. Results: The MEV construct exhibited strong antigenicity, non-allergenicity, and non-toxicity, with stable tertiary structure and favorable physicochemical properties. Docking and dynamics simulations demonstrated high binding affinity and stability with TLR4 (ΔG = −16.2 kcal/mol), while immune simulations predicted durable humoral and cellular immune responses with broad population coverage (≈89%). Codon optimization confirmed high expression potential in E. coli K12. Conclusions: The pangenome-guided immunoinformatics approach enabled the identification of conserved antigenic proteins and rational design of a promising multi-epitope vaccine candidate against MDR C. violaceum. The construct exhibits favorable immunogenic and structural features, supporting its potential for experimental validation and future development as a preventive immunotherapeutic against emerging MDR pathogens. Full article

Cholangiopathies encompass a wide range of chronic liver diseases that target biliary epithelial cells, leading to significant morbidity and mortality due to their progressive nature, limited treatment options, and complex clinical management. Currently, clinically validated biomarkers capable of distinguishing obstructive cholangiopathies, such as biliary atresia (BA), from other cholangiopathies are lacking, hindering timely intervention. RNA-binding proteins (RBPs) have been increasingly linked to human diseases but their roles in cholangiopathies remain underexplored. We assessed the expression of the RBP epithelial splicing regulatory protein 1 (ESRP1) in murine models of cholangiopathies and in the human system. Our findings demonstrate that ESRP1 is highly and specifically expressed in cholestatic liver injury models, including bile duct-ligated, diethoxycarboncyl-1,4-dihydrocollidine-treated, and Mdr2^−/− mice when compared with other liver injury models. Importantly, ESRP1 is markedly elevated in the livers of patients with BA and cystic fibrosis-related liver disease, localizing to cholangiocytes and peri-biliary hepatic cells, but is minimal in primary sclerosing cholangitis and primary biliary cholangitis. Moreover, patient-derived BA organoids and biliatresone-treated healthy organoids also display ESRP1 expression. Bioinformatics analysis further implicates ESRP1 in key cholangiopathy-associated pathways, warranting deeper mechanistic investigation. Thus, ESRP1 holds potential as a molecular marker for obstructive cholangiopathies, warranting further mechanistic studies. Full article

Background: Nosocomial infections represent a significant clinical burden due to high morbidity, mortality and healthcare costs. Invasive fungal infections, particularly those caused by Candida species, are of growing concern due to increasing antifungal resistance, which limits therapeutic options and worsens patient outcomes. This study aimed to characterize the prevalence, species distribution, antifungal susceptibility profiles, and molecular mechanisms of resistance in clinical Candida isolates from hospitalized patients. Methods: A cross-sectional study was conducted involving 55 hospitalized patients, yielding 60 isolates from blood, secretions, fluids, and catheter tips. Species identification was performed using chromogenic media and confirmed by MALDI-TOF MS. Antifungal susceptibility testing followed CLSI M27-A4 broth microdilution guidelines for amphotericin B, fluconazole and 5-flucytosine. Gene expression of ERG2, ERG11 and MDR1 was evaluated by RT-qPCR after exposure to subinhibitory antifungal concentrations using the 2^−∆∆Ct method. Results:Candida albicans was the most frequent species, followed by Nakaseomyces glabratus, C. tropicalis and C. parapsilosis. Resistance varied among species, with elevated rates for fluconazole. ERG2 was notably overexpressed in amphotericin B-resistant isolates, while ERG11 and MDR1 showed species-dependent variation. Conclusions: Resistance mechanisms in Candida are species-specific and drug-dependent. Accurate species identification and understanding their molecular profiles are essential to guide targeted antifungal therapy and improve clinical outcomes. Full article

Multidrug resistance (MDR) remains a major obstacle in the treatment of ovarian cancer. MDR is often mediated by the overexpression of ATP-binding cassette (ABC) transporters, such as P-glycoprotein (P-gp) and Breast Cancer Resistance Protein (BCRP). In this study, we evaluated the ability of elacridar, a dual P-gp and BCRP inhibitor, to overcome MDR in W1, an ovarian cancer cell line sensitive to Paclitaxel (PAC) and its PAC-resistant variants. Cells were cultured under both two-dimensional (2D) and three-dimensional (3D) conditions to account for differences in tumor-like microenvironments. The MDR1 gene and P-gp protein expression were determined for the analyzed model; P-gp activity was measured by flow-cytometry and fluorescent observation, with and without elacridar. The MTT tests were carried out to evaluate how elacridar, combined with chemotherapeutics, affects cell viability. Our results demonstrate that elacridar effectively inhibited transporter activity and increased cellular sensitivity to PAC and DOX. The inhibitory effect was observed in both 2D and 3D cultures, although the re-sensitization effect in 3D conditions was less pronounced, reflecting the complexity of tumor-specific resistance mechanisms. These findings highlight elacridar as a promising compound for reversing MDR in ovarian cancer and emphasize the importance of 3D models in preclinical drug evaluation. Further studies in advanced in vitro and in vivo models are required to assess the potential of elacridar better. Full article

The substantial interest in plant-based drugs or plant-derived phytocompounds drives researchers to conduct comprehensive investigations on their therapeutic properties. Mollugin, one of the major active constituents of Rubia cardifolia, has been well-studied for its pharmacological properties, demonstrating potent anti-inflammatory properties by suppressing the TAK-1-mediated activation of NF-κB/MAPK and enhancing the Nrf2/HO-1-mediated antioxidant response. It exhibits strong anticancer effects through ferroptosis via IGF2BP3/GPX4 pathways, induces mitochondrial apoptosis, and targets NF-κB, ERK, and PI3K/Akt/mTOR to suppress tumor progression. Mollugin also inhibits JAK2/STAT and PARP1 pathways, suppressing IL-1β expression via the modulation of ZFP91. Moreover, it regulates the MAPK/p38 pathway, promotes neuroprotection, and improves cognitive performance through GLP-1 receptor activation. Mollugin promotes osteogenesis by activating the BMP-2/Smad1/5/8 signaling pathway and downregulates MAPK, Akt, and GSK3β expression, leading to the inhibition of osteoclastogenesis. It overcomes multidrug resistance by downregulating MDR1/P-gp, CREB, NF-κB, and COX-2 through AMPK activation. Its antibacterial effect is mediated by strong binding to FUR, UDP, and IpxB proteins in Enterobacter xiangfangensis. Mollugin mitigates Klebsiella pneumoniae infection, suppresses adipogenesis without causing cytotoxicity, and protects endothelial cells via the BDNF/TrkB-Akt signaling pathway. Synthetic derivatives of mollugin, such as oxomollugin and azamollugin, have shown enhanced anticancer and anti-inflammatory effects by regulating EGFR, PKM2, TLR4/MyD88/IRAK/TRAF6, and NF-κB/IRF3 pathways with improved solubility and stability. Collectively, these findings emphasize the broad-spectrum activity of mollugin. This review provides a critical interpretation of the mechanistic pathways regulated by mollugin and its derivatives, emphasizing their pharmacological significance and exploring their potential for future translation as multitarget drug candidates. Full article

Multidrug resistance (MDR) presents a significant challenge in the treatment of glioblastoma. We evaluated six novel adamantane–sclareol hybrids that integrate a natural labdane diterpene scaffold with an adamantane moiety to address this issue. Compounds 2, 5, and 6 demonstrated the ability to bypass P-glycoprotein (P-gp)-mediated resistance in resistant U87-TxR cells and induced collateral sensitivity, with compound 2 exhibiting the highest selectivity for glioblastoma compared to normal glial cells. Mechanistic studies revealed that compounds 2 and 5 selectively triggered early apoptosis in MDR cells, significantly elevated levels of H₂O₂ and peroxynitrite, and disrupted mitochondrial membrane potential. Additionally, these compounds altered the expression of key genes involved in glutathione (GSH) and thioredoxin (Trx) antioxidant defense systems and increased ASK1 protein levels, indicating the activation of ROS-driven apoptotic signaling. Both compounds inhibited P-gp function, leading to enhanced intracellular accumulation of rhodamine 123 (Rho 123) and synergistically sensitized U87-TxR cells to paclitaxel (PTX). A preliminary Rag1 xenograft study demonstrated that compound 5 effectively suppressed tumor growth without causing significant weight loss. Collectively, these findings position adamantane–sclareol hybrids, particularly compounds 2 and 5, as promising strategies that exploit an MDR-associated reactive oxygen species (ROS) vulnerability, combining selective cytotoxicity, redox disruption, and P-gp modulation to eliminate resistant glioblastoma cells and enhance the efficacy of chemotherapeutics. Full article

Multidrug resistance (MDR) remains a significant obstacle to effective cancer chemotherapy, primarily due to overexpression of P-glycoprotein (P-gp), which reduces intracellular accumulation of cytotoxic drugs. This study evaluated the pharmacological potential of the glycyrrhetinic acid derivative soloxolone N-3-(dimethylamino)propylamide (Sol-DMAP) as a biocompatible P-gp inhibitor with hepatoprotective properties. Using a murine model of P-gp-overexpressing RLS40 lymphosarcoma, we demonstrated that Sol-DMAP significantly enhanced the antitumor efficacy of doxorubicin (DOX) by increasing its intratumoral concentration 4.7-fold without enhancing systemic toxicity. Independently, Sol-DMAP exhibited direct antitumor activity, reducing tumor growth in vivo and inducing apoptosis and G1-phase arrest in RLS40 cells in vitro. In addition, Sol-DMAP mitigated DOX-induced hepatic injury by reducing necrotic and dystrophic changes in liver tissue and restoring heme oxygenase 1 (Hmox1) expression. Further studies in HepG2 cells confirmed that Sol-DMAP activated the NRF2-dependent antioxidant response, upregulating HMOX1, GCLC, GCLM, and NQO1 genes. Molecular docking revealed that Sol-DMAP can disrupt the KEAP1-NRF2 interaction, likely leading to NRF2 activation. Collectively, these findings demonstrate that Sol-DMAP effectively reverses P-gp-mediated MDR while protecting the liver from oxidative stress, highlighting its potential as a multifunctional scaffold for the development of safer and more effective chemotherapeutic adjuvants. Full article

Uropathogenic Escherichia coli (UPEC) is the leading cause of urinary tract infections (UTIs) and a major contributor to the global antimicrobial resistance crisis. The increasing prevalence of multidrug-resistant (MDR) strains, including expanded-spectrum β-lactamases (ESBL) and carbapenemase-producing isolates, severely limits treatment options. This review provides an overview on the key molecular mechanisms of UPEC antibiotic resistance, such as enzymatic inactivation, target-site mutations, efflux pump activity, and biofilm formation. Beyond conventional antibiotics, special emphasis is placed on phytochemical strategies as promising alternatives. Flavonoids, alkaloids, terpenoids, and essential oils exhibit antibacterial, anti-adhesive, and antibiofilm properties. These natural bioactive compounds modulate motility, suppress fimbrial expression, inhibit quorum sensing, and enhance antibiotic efficacy, acting both as standalone agents and as adjuvants. Current in vitro and in vivo studies highlight the potential of plant-derived compounds and biologically based therapies to combat UPEC. However, challenges related to standardization, bioavailability, and clinical validation remain unresolved. Integrating molecular mechanistic insights with advanced phytochemical research may offers a sustainable and effective strategy for mitigating UPEC antibiotic resistance. Full article

Microplastics derived from biodegradable PBAT film, widely used in agriculture, pose ecological and biological hazards. This study explores how Trichoderma harzianum T4 mitigates this microplastic-induced stress in Nicotiana benthamiana. Using five experimental setup-control (CK), low/high-dose aged microplastics (MP80/MP320), and their co-treatments with T. harzianum T4 (MP80+T4/MP320+T4), multi-omics analyses reveal the microplastic stress-alleviating mechanisms of T. harzianum T4. Aged microplastics significantly inhibit plant growth, promote reactive oxygen species (ROS) and malondialdehyde (MDA) accumulation, and disrupt metabolic homeostasis. Conversely, T. harzianum T4 activates the plant antioxidant defense system, reducing ROS/MDA levels and upregulating superoxide dismutase (SOD)/peroxidase (POD) activities, and promotes biomass. Transcriptomic analysis shows T. harzianum T4 reverses gene expression patterns disrupted by microplastics, particularly in DNA replication and pentose–glucuronic acid pathways. Metagenomic sequencing indicates T. harzianum T4 restores soil microbial diversity, increases the abundance of Bacteroidota and Myxococcota, downregulates antibiotic resistance genes (e.g., tetA5, MDR), and upregulates carbohydrate-active enzymes (CAZys), thereby enhancing carbon metabolism. In conclusion, T. harzianum T4 alleviates microplastic stress through a tripartite mechanism: activating plant stress-response gene networks, reshaping soil microbial communities, and modulating functional gene expression, offering a promising bioremediation strategy. Full article

This study investigated the molecular epidemiology, virulence, antimicrobial resistance, and mobile genetic elements (MGEs) of Salmonella enterica serovar I 4,[5],12:i:- isolates collected in Jeollanam-do, South Korea, between 2021 and 2023. A total of 135 isolates were tested for antimicrobial susceptibility and 14 virulence-associated genes were screened by PCR. Pulsed-field gel electrophoresis (PFGE) assessed clonal relatedness, and whole-genome sequencing (WGS) enabled multilocus sequence typing (MLST), core genome MLST (cgMLST), SNP phylogeny, resistance gene detection, and MGE analysis. Nine virulence profiles (VP1–VP9) were identified. VP1 (74.1%) was strongly associated with multidrug resistance (MDR), while VP2 (14.8%), which carried plasmid-encoded spv genes, remained largely susceptible. Overall, 83.7% of isolates were resistant to at least one antimicrobial, and 65.2% were MDR, with ampicillin and tetracycline consistently forming the backbone of MDR phenotypes. PFGE revealed high genetic diversity, with 72 pulsotypes, yet certain clones (e.g., SMOX01.006, SMOX01.012) were widely distributed and corresponded to VP2 isolates. WGS confirmed two dominant sequence types, ST34 (n = 24) and ST19 (n = 20), with SNP phylogeny showing VP1 isolates mainly clustered with ST34 and VP2 with ST19. Genotype–phenotype concordance showed strong agreement for most antimicrobials, except cefoxitin, ciprofloxacin, amikacin, and trimethoprim/sulfamethoxazole. MGE analysis revealed that tet(B) was consistently associated with ISVsa5, while ISEc59 was linked to multiple resistance genes, though only aac(3)-IV was phenotypically expressed. These findings demonstrate that MDR and virulence gene composition were closely associated with clonal clustering and that MGEs may contribute to resistance gene expression. This study provides a basis for understanding the dissemination of resistant and virulent Salmonella in the region and underscores the need for continuous genomic surveillance. Full article

Background: Multidrug resistance (MDR) remains a major obstacle in cancer chemotherapy, and overexpression of ABCB1 plays a critical role in the pathogenesis of MDR. Despite decades of research, significant clinical progress in the development of ABCB1 inhibitors has yet to be achieved. The small-molecule H89 is originally identified as an inhibitor of protein kinase A (PKA), but it also exhibits various functions unrelated to the PKA. This study investigates H89 as a novel ABCB1-inhibitor to reverse MDR in colorectal cancer (CRC). Methods: Cytotoxicity assays were performed on ABCB1-overexpressing MDR cell line HCT-8/V and parental CRC cell line HCT-8. Drug accumulation was quantified via flow cytometry, and cell cycle effects were analyzed using propidium iodide staining. The ATPase activity of ABCB1 was detected using an ATPase activity assay kit. Molecular docking utilized the ABCB1 crystal structure. Results: Both 3 μM and 10 μM H89 significantly reverses resistance to two ABCB1 substrate drugs (doxorubicin and vincristine) in HCT-8/V cells in a dose-dependent manner, with no such effect observed inHCT-8 cells. The combination of H89 and doxorubicin or vincristine resulted in a significant increase in the proportion ofHCT-8/Vcells in the sub-G1 and G2/M phases. Further mechanistic studies reveal that H89 exerts its effect by inhibiting the drug efflux function of ABCB1, thereby increasing the intracellular accumulation of the substrate drugs and reversing multidrug resistance. Furthermore, H89 did not alter the expression of ABCB1. H89 effectively inhibited the ATPase activity of ABCB1. Molecular docking simulations revealed the binding mode of H89 with ABCB1. Conclusions: The combination of H89 with ABCB1 substrate drugs significantly reverses multidrug resistance in colorectal cancer. These findings provide a strong theoretical and experimental foundation for the development of novel MDR-reversing agents targeting ABCB1. Full article

The active efflux of drugs by adenosine triphosphate (ATP)-binding cassette (ABC) trans-porters, such as multidrug resistance protein 1 (MDR1/ABCB1), multidrug resistance-associated protein 1 and 2 (MRP1/ABCC1; MRP2/ABCC2), and breast cancer resistance protein (BCRP/ABCG2), is a well-established mechanism contributing to multidrug resistance (MDR). Interestingly, various vitamin A-based molecules have been found to influence the expression or function of these transporters. This work investigated the current evidence on the effects of retinoids, rexinoids, and carotenoids on ABC transporters and their potential to reverse MDR. Several studies indicated that these compounds could inhibit ABC transporter activity at non-toxic concentrations, either by downregulating gene/protein expression or by directly blocking efflux function. These effects were often associated with increased chemosensitivity to several conventional anticancer agents. Overall, the degree of inhibition varied depending on several factors, including compound type and their chemical modification, dose, incubation time, treatment timing, the type of target cells, method of transporter overexpression, and coadministration with other compounds. Although particular attention was paid to elucidating the underlying mechanisms, current knowledge in this area remains limited. Moreover, extensive in vivo and clinical studies validating these findings are still lacking, emphasizing the need for further research to evaluate their translational potential. Full article

Resistance to conventional anti-tumor drugs is one of the significant challenges in oncology, responsible for treatment failure and patient death. Introduction of the targeted drugs (e.g., small molecule tyrosine kinase inhibitors (TKIs) and monoclonal antibodies) in cancer therapy significantly improved overall survival (OS) and progression-free survival (PFS) rates for selected groups of cancer patients and delayed the progression of advanced forms of human malignancies. However, the development of secondary resistance to the targeted drugs remains an unbeatable obstacle to a successful outcome in the long run, thereby making prognosis unfavorable for cancer patients with advanced, recurrent, and metastatic forms of disease. The review focuses on several mechanisms that regulate cancer resistance to conventional chemotherapies. This includes the upregulation of main types of ABC transporters (e.g., ABCB1, ABCC1, and ABCG2), which provides the efflux of chemotherapeutic agents from cancer cells. Additionally, the activation of diverse DNA damage repair (DDR) pathways, epithelial-to-mesenchymal transition (EMT), and the population of cancer stem cells (CSCs) are also discussed in detail, thereby illustrating the diverse molecular mechanisms of cancer sensitivity to chemotherapies. Recently, several TKIs, including those that were initially developed to specifically target FGFR and VEGFR pathways, have also been reported to exhibit “off-target” effects by interacting with ABC transporters and inhibiting their function. This, in turn, illustrates their potency in retaining chemotherapeutic agents within cancer cells and possessing a chemosensitizing function. Of note, FGFR and VEGFR inhibitors may behave as inhibitors or substrates of ABC transporters, depending on the expression of specific pumps and affinity for them, concentrations, and types of co-administered agents, thereby disclosing the complexity of this scenario. Additionally, the aforementioned RTKI can interfere with the other molecular mechanisms regulating tumor sensitivity to conventional chemotherapies, including the regulation of diverse DDR pathways, EMT, and the population of CSCs. Thereby, the aforementioned “off-target” functions of FGFR and VEGFR inhibitors can open novel approaches towards anti-cancer therapies and strategies aimed at counteracting cancer multidrug resistance (MDR), which is important especially as second- or third-line treatments in patients who have progressed on modern chemotherapeutic regimens. Notably, the strategy of using TKIs to potentiate the clinical efficacy of chemotherapies can extend beyond inhibitors of FGFR and VEGFR signaling pathways, thereby providing a rationale for repurposing existing TKIs as an attractive therapeutic approach to overcome cancer chemoresistance. Full article

Background: Multidrug resistance (MDR), primarily driven by P-glycoprotein (P-gp)-mediated drug efflux, presents a significant challenge in cancer therapy, contributing to chemotherapy failure and poor patient outcomes. Objectives: In this study, we explored the potential of manidipine (MA), a clinically approved calcium channel blocker, to reverse P-gp-mediated MDR through modulation of calcium signaling via nuclear factor of activated T cells 2 (NFAT2). Methods: Paclitaxel (PTX) resistance ABCB1-overexpressing cancer in vitro and in vivo were used for evualting the anti-MDR effects of MA, as well as the underlying mechanism with siRNA of NFAT2. Results: We found that MA at non-toxic concentrations (0.6–5.4 μM) significantly sensitize drug-resistant colorectal (HCT-8/T) and non-small cell lung (A549/T) cells to PTX, reducing its IC₅₀ by up to 1328-fold in vitro models. Mechanistically, MA inhibited P-gp efflux activity without altering its expression, as shown by an increased intracellular accumulation of doxorubicin and Flutax-2 (2.3- and 3.1-fold, respectively) and dose-dependent modulation of ATPase activity (EC₅₀ = 4.16 μM). Notably, MA reduced intracellular calcium levels (52% reduction, p < 0.001) and downregulated NFAT2, an oncogene overexpressed in resistant cells. In vivo, MA (3.5 mg/kg) synergizes with PTX to inhibit tumor growth by 68% (p < 0.001) in A549/T xenograft model, without an observable decrease in weight. Conclusions: In sum, all these results position MA as a novel NFAT2 inhibitor to overcome P-gp-mediated MDR via modulating calcium signaling, which points to further investigation for its clinical applications. Full article