Multidrug resistance (MDR) represents one of the major concerns in cancer therapy as it may cause reduced efficacy of chemotherapeutic drugs due to the overexpression of ABC transporters, particularly P-glycoprotein (P-gp). This study explores the potential of novel amphiphilic diblock (DB) copolymers composed of poly[N-(2-hydroxypropyl)methacrylamide]-based copolymers (PHPMA) and poly(propylene oxide) (PPO) to overcome MDR mechanisms. The DB copolymers and their doxorubicin (Dox) conjugates significantly increased Dox accumulation in P-gp positive cells, markedly sensitizing them to Dox cytotoxic activity. The underlying mechanisms included depletion of intracellular ATP with subsequent inhibition of P-gp mediated drug efflux, an altered mitochondrial membrane potential, and increased ROS production. Moreover, the DB-Dox conjugates inhibited tumor growth in vivo more effectively compared to the corresponding PHPMA-based drug delivery system. Copolymers with additionally loaded PPO in the micelle core demonstrated superior efficacy in terms of P-gp inhibition, ATP depletion, and chemosensitizing effect in vitro, as well as antitumor activity in vivo. DB copolymers effectively depleted ATP levels both in vitro and in vivo using patient-derived xenograft (PDX) models, underscoring their capacity to enhance the effectiveness of standard chemotherapy and translational potential.

• Klíčová slova
• Diblock copolymers, Drug delivery system, HPMA copolymer, Intracellular ATP depletion, Multidrug resistance, P-glycoprotein inhibition, PPO, Sensitization to chemotherapy,
• MeSH
• adenosintrifosfát metabolismus   MeSH
• chemorezistence účinky léků   MeSH
• doxorubicin * aplikace a dávkování   chemie   terapeutické užití   MeSH
• lidé MeSH
• methakryláty chemie   MeSH
• micely MeSH
• mnohočetná léková rezistence účinky léků   MeSH
• myši inbrední BALB C MeSH
• myši nahé MeSH
• myši MeSH
• nádorové buněčné linie MeSH
• nádory farmakoterapie   metabolismus   patologie   MeSH
• nosiče léků * chemie   MeSH
• P-glykoprotein * metabolismus   MeSH
• polymery chemie   MeSH
• polypropyleny * chemie   MeSH
• propylenglykoly * chemie   aplikace a dávkování   MeSH
• protinádorová antibiotika * aplikace a dávkování   chemie   terapeutické užití   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• adenosintrifosfát MeSH
• doxorubicin * MeSH
• methakryláty MeSH
• micely MeSH
• nosiče léků * MeSH
• P-glykoprotein * MeSH
• polymery MeSH
• polypropylene glycol MeSH Prohlížeč
• polypropyleny * MeSH
• propylenglykoly * MeSH
• protinádorová antibiotika * MeSH

Inflammation is a hallmark of cancer. It contributes to a heterogeneous, hyperpermeable, and poorly perfused tumor vasculature, as well as to a dense and disorganized extracellular matrix, which together negatively affect drug delivery. Reasoning that glucocorticoids have pleiotropic effects, we use clinical-stage dexamethasone liposomes (LipoDex) to prime the tumor microenvironment for improved drug delivery and enhanced treatment efficacy. We show that LipoDex priming improves tumor vascular function and reduces extracellular matrix deposition. Single-cell sequencing corroborates LipoDex-mediated inhibition of pro-inflammatory, pro-angiogenic, and pro-fibrogenic gene expression in mononuclear cells, tumor-associated macrophages, and cancer-associated fibroblasts. Multimodal optical imaging illustrates that LipoDex pre-treatment increases the tumor accumulation and intratumoral distribution of subsequently administered polymeric and liposomal drug delivery systems. Using Doxil as a prototypic nanodrug, we finally show that LipoDex priming promotes antitumor treatment efficacy. Altogether, our findings demonstrate that desmoplastic tumors can be primed for improved drug targeting and therapy using clinical-stage glucocorticoid liposomes.

• Klíčová slova
• cancer-associated fibroblasts, corticosteroids, drug targeting, liposomes, nanomedicine, tumor microenvironment, tumor priming, tumor-associated macrophages,
• Publikační typ
• časopisecké články MeSH

• Publikační typ
• tisková chyba MeSH

The development of stimuli-responsive drug delivery systems enables targeted delivery and environment-controlled drug release, thereby minimizing off-target effects and systemic toxicity. We prepared and studied tailor-made dual-responsive systems (thermo- and pH-) based on synthetic diblock copolymers consisting of a fully hydrophilic block of poly[N-(1,3-dihydroxypropyl)methacrylamide] (poly(DHPMA)) and a thermoresponsive block of poly[N-(2,2-dimethyl-1,3-dioxan-5-yl)methacrylamide] (poly(DHPMA-acetal)) as drug delivery and smart stimuli-responsive materials. The copolymers were designed for eventual medical application to be fully soluble in aqueous solutions at 25 °C. However, they form well-defined nanoparticles with hydrodynamic diameters of 50-800 nm when heated above the transition temperature of 27-31 °C. This temperature range is carefully tailored to align with the human body's physiological conditions. The formation of the nanoparticles and their subsequent decomposition was studied using dynamic light scattering (DLS), transmission electron microscopy (TEM), isothermal titration calorimetry (ITC), and nuclear magnetic resonance (NMR). 1H NMR studies confirmed that after approximately 20 h of incubation at pH 5, which closely mimics tumor microenvironment, approximately 40% of the acetal groups were hydrolyzed, and the thermoresponsive behavior of the copolymers was lost. This smart polymer response led to disintegration of the supramolecular structures, possibly releasing the therapeutic cargo. By tuning the transition temperature to the values relevant for medical applications, we ensure precise and effective drug release. In addition, our systems did not exhibit any cytotoxicity against any of the three cell lines. Our findings underscore the immense potential of these nanoparticles as eventual advanced drug delivery systems, especially for cancer therapy.

• Klíčová slova
• RAFT polymerization, drug delivery systems, pH-sensitive polymers, self-assembling block copolymers, thermoresponsive polymers,
• MeSH
• biokompatibilní materiály * chemie   chemická syntéza   farmakologie   MeSH
• doxorubicin * farmakologie   chemie   MeSH
• koncentrace vodíkových iontů MeSH
• lékové transportní systémy * MeSH
• lidé MeSH
• nanočástice * chemie   MeSH
• polymery * chemie   MeSH
• povrchové vlastnosti MeSH
• protinádorová antibiotika * farmakologie   chemie   MeSH
• screeningové testy protinádorových léčiv MeSH
• teplota MeSH
• testování materiálů MeSH
• uvolňování léčiv MeSH
• velikost částic MeSH
• viabilita buněk účinky léků   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• biokompatibilní materiály * MeSH
• doxorubicin * MeSH
• polymery * MeSH
• protinádorová antibiotika * MeSH

The effective treatment of inflammatory diseases, particularly their chronic forms, is a key task of modern medicine. Herein, we report the synthesis and evaluation of biocompatible polymer conjugates based on N-2-(hydroxypropyl)methacrylamide copolymers enabling the controlled release of acetylsalicylic acid (ASA)-based anti-inflammatory drugs under specific stimuli. All polymer nanotherapeutics were proposed as water-soluble drug delivery systems with a hydrodynamic size below 10 nm ensuring suitability for the parenteral application and preventing opsonization by the reticuloendothelial system. The nanotherapeutics bearing an ester-bound ASA exhibited long-term release of the ASA/salicylic acid mixture, while the nanotherapeutics carrying salicylic acid hydrazide (SAH) ensured the selective release of SAH in the acidic inflammatory environment thanks to the pH-sensitive hydrazone bond between the polymer carrier and SAH. The ASA- and SAH-containing nanotherapeutics inhibited both cyclooxygenase isoforms and/or the production of pro-inflammatory mediators. Thanks to their favorable design, they can preferentially accumulate in the inflamed tissue, resulting in reduced side effects and lower dosage, and thus more effective and safer treatment.

• Klíčová slova
• Acetylsalicylic acid, Drug delivery, HPMA, Inflammation, Nanotherapeutics, Salicylic acid hydrazide,
• MeSH
• akrylamidy chemie   farmakologie   aplikace a dávkování   MeSH
• antiflogistika farmakologie   aplikace a dávkování   chemie   MeSH
• Aspirin * aplikace a dávkování   farmakologie   chemie   MeSH
• cyklooxygenasy metabolismus   MeSH
• inhibitory cyklooxygenasy farmakologie   aplikace a dávkování   chemie   MeSH
• léky s prodlouženým účinkem * MeSH
• mediátory zánětu metabolismus   MeSH
• myši MeSH
• nanočástice * chemie   MeSH
• nosiče léků chemie   MeSH
• polymery * chemie   aplikace a dávkování   MeSH
• uvolňování léčiv MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• akrylamidy MeSH
• antiflogistika MeSH
• Aspirin * MeSH
• cyklooxygenasy MeSH
• inhibitory cyklooxygenasy MeSH
• léky s prodlouženým účinkem * MeSH
• mediátory zánětu MeSH
• N-(2-hydroxypropyl)methacrylamide MeSH Prohlížeč
• nosiče léků MeSH
• polymery * MeSH

The clinical prospects of cancer nanomedicines depend on effective patient stratification. Here we report the identification of predictive biomarkers of the accumulation of nanomedicines in tumour tissue. By using supervised machine learning on data of the accumulation of nanomedicines in tumour models in mice, we identified the densities of blood vessels and of tumour-associated macrophages as key predictive features. On the basis of these two features, we derived a biomarker score correlating with the concentration of liposomal doxorubicin in tumours and validated it in three syngeneic tumour models in immunocompetent mice and in four cell-line-derived and six patient-derived tumour xenografts in mice. The score effectively discriminated tumours according to the accumulation of nanomedicines (high versus low), with an area under the receiver operating characteristic curve of 0.91. Histopathological assessment of 30 tumour specimens from patients and of 28 corresponding primary tumour biopsies confirmed the score's effectiveness in predicting the tumour accumulation of liposomal doxorubicin. Biomarkers of the tumour accumulation of nanomedicines may aid the stratification of patients in clinical trials of cancer nanomedicines.

• MeSH
• biologické markery metabolismus   MeSH
• doxorubicin * terapeutické užití   analogy a deriváty   MeSH
• lidé MeSH
• makrofágy spojené s nádory metabolismus   MeSH
• myši MeSH
• nádorové biomarkery metabolismus   MeSH
• nádorové buněčné linie MeSH
• nádory * patologie   metabolismus   farmakoterapie   MeSH
• nanomedicína * metody   MeSH
• polyethylenglykoly MeSH
• strojové učení MeSH
• xenogenní modely - testy protinádorové aktivity MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• biologické markery MeSH
• doxorubicin * MeSH
• liposomal doxorubicin MeSH Prohlížeč
• nádorové biomarkery MeSH
• polyethylenglykoly MeSH

Drug delivery to central nervous pathologies is compromised by the blood-brain barrier (BBB). A clinically explored strategy to promote drug delivery across the BBB is sonopermeation, which relies on the combined use of ultrasound (US) and microbubbles (MB) to induce temporally and spatially controlled opening of the BBB. We developed an advanced in vitro BBB model to study the impact of sonopermeation on the delivery of the prototypic polymeric drug carrier pHPMA as a larger molecule and the small molecule antiviral drug ribavirin. This was done under standard and under inflammatory conditions, employing both untargeted and RGD peptide-coated MB. The BBB model is based on human cerebral capillary endothelial cells and human placental pericytes, which are co-cultivated in transwell inserts and which present with proper transendothelial electrical resistance (TEER). Sonopermeation induced a significant decrease in TEER values and facilitated the trans-BBB delivery of fluorescently labeled pHPMA (Atto488-pHPMA). To study drug delivery under inflamed endothelial conditions, which are typical for e.g. tumors, neurodegenerative diseases and CNS infections, tumor necrosis factor (TNF) was employed to induce inflammation in the BBB model. RGD-coated MB bound to and permeabilized the inflamed endothelium-pericyte co-culture model, and potently improved Atto488-pHPMA and ribavirin delivery. Taken together, our work combines in vitro BBB bioengineering with MB-mediated drug delivery enhancement, thereby providing a framework for future studies on optimization of US-mediated drug delivery to the brain.

• Klíčová slova
• Blood-brain barrier, Drug delivery, Microbubbles, Sonopermeation, Ultrasound,
• MeSH
• antivirové látky aplikace a dávkování   chemie   farmakologie   farmakokinetika   MeSH
• endoteliální buňky * účinky léků   metabolismus   MeSH
• hematoencefalická bariéra * metabolismus   MeSH
• kokultivační techniky * MeSH
• lékové transportní systémy metody   MeSH
• lidé MeSH
• mikrobubliny * MeSH
• oligopeptidy * chemie   aplikace a dávkování   farmakokinetika   MeSH
• pericyty * metabolismus   účinky léků   MeSH
• polymery chemie   aplikace a dávkování   MeSH
• ribavirin aplikace a dávkování   chemie   farmakokinetika   MeSH
• ultrazvukové vlny MeSH
• zánět farmakoterapie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• antivirové látky MeSH
• arginyl-glycyl-aspartic acid MeSH Prohlížeč
• oligopeptidy * MeSH
• polymery MeSH
• ribavirin MeSH

Liposomes are one of the most important drug delivery vectors, nowadays used in clinics. In general, polyethylene glycol (PEG) is used to ensure the stealth properties of the liposomes. Here, we have employed hydrophilic, biocompatible and highly non-fouling N-(2-hydroxypropyl) methacrylamide (HPMA)-based copolymers containing hydrophobic cholesterol anchors for the surface modification of liposomes, which were prepared by the method of lipid film hydration and extrusion through 100 nm polycarbonate filters. Efficient surface modification of liposomes was confirmed by transmission electron microscopy, atomic force microscopy, and gradient ultracentrifugation. The ability of long-term circulation in the vascular bed was demonstrated in rabbits after i.v. application of fluorescently labelled liposomes. Compared to PEGylated liposomes, HPMA-based copolymer-modified liposomes did not induce specific antibody formation and did not activate murine and human complement. Compared with PEGylated liposomes, HPMA-based copolymer-modified liposomes showed a better long-circulating effect after repeated administration. HPMA-based copolymer-modified liposomes thus represent suitable new candidates for a generation of safer and improved liposomal drug delivery platforms.

• Klíčová slova
• Complement activation, Drug delivery system, HPMA copolymer, Long-circulating liposomes, Stealth liposomes,
• MeSH
• akrylamidy chemie   MeSH
• aktivace komplementu účinky léků   MeSH
• cholesterol chemie   krev   MeSH
• hydrofobní a hydrofilní interakce * MeSH
• králíci MeSH
• lékové transportní systémy MeSH
• lidé MeSH
• liposomy * MeSH
• myši MeSH
• polyethylenglykoly * chemie   MeSH
• polymery chemie   MeSH
• povrchové vlastnosti * MeSH
• zvířata MeSH
• Check Tag
• králíci MeSH
• lidé MeSH
• mužské pohlaví MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• akrylamidy MeSH
• cholesterol MeSH
• liposomy * MeSH
• polyethylenglykoly * MeSH
• polymery MeSH

Fluorescence-based contrast agents enable real-time detection of solid tumors and their neovasculature, making them ideal for use in image-guided surgery. Several agents have entered late-stage clinical trials or secured FDA approval, suggesting they are likely to become the standard of care in cancer surgeries. One of the key parameters to optimize in contrast agents is molecular size, which dictates much of the pharmacokinetic and pharmacodynamic properties of the agent. Here, we describe the development of a class of protease-activated quenched fluorescent probes in which a N-(2-hydroxypropyl)methacrylamide copolymer is used as the primary scaffold. This copolymer core provides a high degree of probe modularity to generate structures that cannot be achieved with small molecules and peptide probes. We used a previously validated cathepsin substrate and evaluated the effects of length and type of linker, as well as the positioning of the fluorophore/quencher pair on the polymer core. We found that the polymeric probes could be optimized to achieve increased overall signal and tumor-to-background ratios compared to the reference small molecule probe. Our results also revealed multiple structure-activity relationship trends that can be used to design and optimize future optical imaging probes. Furthermore, they confirm that a hydrophilic polymer is an ideal scaffold for use in optical imaging contrast probes, allowing a highly modular design that enables efficient optimization to maximize probe accumulation and overall biodistribution properties.

• Klíčová slova
• HPMA copolymer, cancer, fluorescence, iBody, imaging, protease,
• MeSH
• akrylamidy chemie   MeSH
• fluorescenční barviva * chemie   chemická syntéza   MeSH
• lidé MeSH
• myši MeSH
• nádorové buněčné linie MeSH
• nádory * diagnostické zobrazování   MeSH
• optické zobrazování metody   MeSH
• polymery chemie   MeSH
• proteasy metabolismus   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• akrylamidy MeSH
• fluorescenční barviva * MeSH
• N-(2-hydroxypropyl)methacrylamide MeSH Prohlížeč
• polymery MeSH
• proteasy MeSH

Immune checkpoint blockade (ICB) using monoclonal antibodies against programmed cell death protein 1 (PD-1) or programmed death-ligand 1 (PD-L1) is the treatment of choice for cancer immunotherapy. However, low tissue permeability, immunogenicity, immune-related adverse effects, and high cost could be possibly improved using alternative approaches. On the other hand, synthetic low-molecular-weight (LMW) PD-1/PD-L1 blockers have failed to progress beyond in vitro studies, mostly due to low binding affinity or poor pharmacological characteristics resulting from their limited solubility and/or stability. Here, we report the development of polymer-based anti-human PD-L1 antibody mimetics (α-hPD-L1 iBodies) by attaching the macrocyclic peptide WL12 to a N-(2-hydroxypropyl)methacrylamide copolymer. We characterized the binding properties of iBodies using surface plasmon resonance, enzyme-linked immunosorbent assay, flow cytometry, confocal microscopy, and a cellular ICB model. We found that the α-hPD-L1 iBodies specifically target human PD-L1 (hPD-L1) and block the PD-1/PD-L1 interaction in vitro, comparable to the atezolizumab, durvalumab, and avelumab licensed monoclonal antibodies targeting PD-L1. Our findings suggest that iBodies can be used as experimental tools to target hPD-L1 and could serve as a platform to potentiate the therapeutic effect of hPD-L1-targeting small molecules by improving their affinity and pharmacokinetic properties.

• Klíčová slova
• HPMA copolymer, PD-1, PD-L1, T-cell, antibody mimetic, immune checkpoint, immunosuppression, immunotherapy, inhibitor, tumor immunology,
• MeSH
• antigeny CD274 * antagonisté a inhibitory   imunologie   metabolismus   MeSH
• inhibitory kontrolních bodů * farmakologie   chemie   MeSH
• lidé MeSH
• monoklonální protilátky chemie   farmakologie   MeSH
• nádorové buněčné linie MeSH
• polymery chemie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• antigeny CD274 * MeSH
• CD274 protein, human MeSH Prohlížeč
• inhibitory kontrolních bodů * MeSH
• monoklonální protilátky MeSH
• polymery MeSH