Chemotherapy targeted towards the tumor cells results in more effective treatment with limited undesirable effects. The project focuses on preclinical evaluation of new biodegradable micellar polymer drug carriers - amphiphilic block copolymers of polypropyleneglycol and N-(2-hydroxypropyl)methacrylamide-based copolymers, and their conjugates with covalently bound anticancer drugs. The conjugates operate through three synergic mechanisms: enhanced drug accumulation in solid tumors followed by controlled drug release and concurrent overcoming multidrug resistance due to inherent ability of the carrier itself. The study is centered on treatment of chemoresistant cancers using the synergy mentioned above and carrier-driven reduction of drug side effects. The effect of the polymer micelles with cancerostatics and the carrier itself will be evaluated on tumor cells obtained from the patients with head and neck squamous cell carcinomas. Analysis of the tumor microenvironment, namely PD-Ll/2 expression, will indicate applicability of the proposed therapy in immunooncotherapeutic regimes.

Chemoterapie směrovaná přímo proti nádorovým buňkám vede k účinnější léčbě při omezení nežádoucích efektů. Projekt se soustřeďuje na preklinické hodnocení nových micelárních polymerních nosičů léčiv – amfifilních blokových kopolymerů na bázi polypropylenglykolu a kopolymerů N-(2-hydroxypropyl)metakrylamidu a jejich konjugátů s kovalentně navázanými protinádorovými léčivy. Konjugáty jsou aktivní díky třem synergickým mechanismům: zvýšené akumulaci léčiva ve tkáni solidních nádorů s následným kontrolovaným uvolněním léčiva a současným překonáním vícečetné lékové rezistence díky vlastnostem samotného nosiče. Studie je zaměřena na léčbu chemorezistentních nádorů a je založena na využití výše zmíněné synergie v kombinaci s redukcí nežádoucích vedlejších účinků léčiv navázaných na nosič. Vliv polymerních micel s kancerostatiky a polymerního nosiče samotného bude testován na nádorových buňkách pacientů s dlaždicobuněčnými karcinomy hlavy a krku. Analýza nádorového mikroprostředí, zejména exprese PD-L1/2, ukáže možnost propojení navrhované léčby s imunoonkoterapeutickými režimy.

• MeSH
• antitumorózní látky terapeutické užití   MeSH
• chemorezistence účinky léků   MeSH
• imunoterapie metody   MeSH
• lidé MeSH
• micely MeSH
• nádorové mikroprostředí MeSH
• nádory terapie   MeSH
• nosiče léků terapeutické užití   MeSH
• polymery terapeutické užití   MeSH
• preklinické hodnocení léčiv MeSH
• synergismus léků MeSH
• Check Tag
• lidé MeSH

• Konspekt
• Patologie. Klinická medicína
• NLK Obory
• onkologie
• farmacie a farmakologie
• farmakoterapie
• NLK Publikační typ
• závěrečné zprávy o řešení grantu AZV MZ ČR

Design, controlled synthesis, physico-chemical and biological characteristics of novel well-defined biodegradable star-shaped copolymers intended for advanced drug delivery is described. These new biocompatible star copolymers were synthesised by grafting monodispersed semitelechelic linear (sL) N-(2-hydroxypropyl)methacrylamide copolymers onto a 2,2-bis(hydroxymethyl)propionic acid (bisMPA)-based polyester dendritic core of various structures. The hydrodynamic diameter of the star copolymer biomaterials can be tuned from 13 to 31 nm and could be adjusted to a given purpose by proper selection of the bisMPA dendritic core type and generation and by considering the sL copolymer molecular weight and polymer-to-core molar ratio. The hydrolytic degradation was proved for both the star copolymers containing either dendron or dendrimer core, showing the spontaneous hydrolysis in duration of few weeks. Finally, it was shown that the therapy with the biodegradable star conjugate with attached doxorubicin strongly suppresses the tumour growth in mice and is fully curative in most of the treated animals at dose corresponding approximately to one fourth of maximum tolerated dose (MTD) value. Both new biodegradable systems show superior efficacy and tumour accumulation over the first generation of star copolymers containing non-degradable PAMAM core.

• MeSH
• akrylamidy MeSH
• biokompatibilní materiály * MeSH
• doxorubicin MeSH
• léčivé přípravky * MeSH
• methakryláty MeSH
• myši MeSH
• nádorové buněčné linie MeSH
• nosiče léků MeSH
• polymery MeSH
• systémy cílené aplikace léků MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH

Multidrug resistance (MDR) is often caused by the overexpression of efflux pumps, such as ABC transporters, in particular, P-glycoprotein (P-gp). Here, we investigate the di- and tri- block amphiphilic polymer systems based on polypropylene glycol (PPO) and copolymers of (N-(2-hydroxypropyl)methacrylamide) (PHPMA) as potential macromolecular inhibitors of P-gp, and concurrently, carriers of drugs, passively targeting solid tumors by the enhanced permeability and retention (EPR) effect. Interestingly, there were significant differences between the effects of di- and tri- block polymer-based micelles, with the former being significantly more thermodynamically stable and showing much higher P-gp inhibition ability. The presence of Boc-protected hydrazide groups or the Boc-deprotection method did not affect the physico-chemical or biological properties of the block copolymers. Moreover, diblock polymer micelles could be loaded with free PPO containing 5-40 wt % of free PPO, which showed increased P-gp inhibition in comparison to the unloaded micelles. Loaded polymer micelles containing more than 20 wt % free PPO showed a significant increase in toxicity; thus, loaded diblock polymer micelles containing 5-15 wt % free PPO are potential candidates for in vitro and in vivo application as potent MDR inhibitors and drug carriers.

• Publikační typ
• časopisecké články MeSH

BACKGROUND: Standard treatment of oropharyngeal squamous cell carcinoma (OPSCC) is associated with high morbidity, whereas immunotherapeutic approaches using PD-1:PD-L1 checkpoint blockade only show moderate response rates in OPSCC patients. Therefore, a better stratification of patients and the development of novel therapeutic protocols are crucially needed. The importance of tumor-infiltrating B cells (TIL-Bs) in shaping antitumor immunity remains unclear; therefore, we analyzed frequency, phenotype, prognostic value and possible roles of TIL-Bs in OPSCC. METHODS: We utilized transcriptomic analysis of immune response-related genes in 18 OPSCC samples with respect to human papillomavirus (HPV) status. The density and localization of CD20+, CD8+ and DC-LAMP+ cells were subsequently analyzed in 72 tissue sections of primary OPSCC samples in relation to patients' prognosis. The immunohistochemical approach was supplemented by flow cytometry-based analysis of phenotype and functionality of TIL-Bs in freshly resected primary OPSCC tissues. RESULTS: We observed significantly higher expression of B cell-related genes and higher densities of CD20+ B cells in HPV-associated OPSCC samples. Interestingly, CD20+ TIL-Bs and CD8+ T cells formed non-organized aggregates with interacting cells within the tumor tissue. The densities of both intraepithelial CD20+ B cells and B cell/CD8+ T cell interactions showed prognostic significance, which surpassed HPV positivity and CD8+ TIL density in stratification of OPSCC patients. High density of TIL-Bs was associated with an activated B cell phenotype, high CXCL9 production and high levels of tumor-infiltrating CD8+ T cells. Importantly, the abundance of direct B cell/CD8+ T cell interactions positively correlated with the frequency of HPV16-specific CD8+ T cells, whereas the absence of B cells in tumor-derived cell cultures markedly reduced CD8+ T cell survival. CONCLUSIONS: Our results indicate that high abundance of TIL-Bs and high density of direct B cell/CD8+ T cell interactions can predict patients with excellent prognosis, who would benefit from less invasive treatment. We propose that in extensively infiltrated tumors, TIL-Bs might recruit CD8+ T cells via CXCL9 and due to a highly activated phenotype contribute by secondary costimulation to the maintenance of CD8+ T cells in the tumor microenvironment.

• MeSH
• adjuvantní chemoradioterapie MeSH
• aktivace lymfocytů MeSH
• B-lymfocyty imunologie   MeSH
• CD8-pozitivní T-lymfocyty imunologie   MeSH
• dlaždicobuněčné karcinomy hlavy a krku imunologie   mortalita   terapie   virologie   MeSH
• dospělí MeSH
• infekce papilomavirem imunologie   mortalita   terapie   virologie   MeSH
• Kaplanův-Meierův odhad MeSH
• kohortové studie MeSH
• krční disekce MeSH
• lidé středního věku MeSH
• lidé MeSH
• mezibuněčná komunikace imunologie   MeSH
• nádorové mikroprostředí imunologie   MeSH
• nádory orofaryngu imunologie   mortalita   terapie   virologie   MeSH
• orofarynx patologie   chirurgie   MeSH
• Papillomaviridae imunologie   izolace a purifikace   MeSH
• prognóza MeSH
• progrese nemoci MeSH
• senioři MeSH
• tumor infiltrující lymfocyty imunologie   MeSH
• výběr pacientů MeSH
• výsledek terapie MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

N-(2-Hydroxypropyl)methacrylamide copolymer conjugates of pirarubicin (THP), P-THP, accumulates selectively in solid tumor tissue by the enhanced permeability and retention (EPR) effect. Despite of high accumulation in solid tumors, some macromolecular antitumor agents show poor therapeutic outcome because of poor tissue diffusion into the tumor as well as obstructed tumor blood flow. Here, we confirmed that cellular uptake of P-THP was 25 times less than that of free THP at 1-4 h incubation time in vitro. The passage of P-THP through the confluent tight-monolayer cells junction was 12 times higher than free THP, and P-THP penetrated deeper into the tumor cell spheroid (1.3-1.7-fold) than free THP in 4 h. In addition, P-THP showed cytotoxicity comparable to that of free THP to tumor-cells in spheroid form, despite of 7 times lower cytotoxicity of P-THP to the monolayer cells to that of free THP in vitro. These results indicate that P-THP administration can exhibit deeper diffusion into the tumor cell spheroid than free THP. As a consequence, P-THP exhibits more efficient antitumor activity than free THP in vivo, which is also supported by better pharmacokinetics and tumor accumulation of P-THP than free THP.

• MeSH
• akrylamidy chemie   MeSH
• antitumorózní látky aplikace a dávkování   farmakokinetika   MeSH
• buněčné sféroidy MeSH
• doxorubicin aplikace a dávkování   analogy a deriváty   farmakokinetika   MeSH
• HCT116 buňky MeSH
• léky antitumorózní - screeningové testy MeSH
• lidé MeSH
• nádory farmakoterapie   patologie   MeSH
• nosiče léků chemie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

We developed a new simplified method for the synthesis of well-defined linear, diblock, or starlike N-(2-hydroxypropyl)methacrylamide (HPMA)-based polymer drug carriers using controlled reversible addition-fragmentation chain transfer polymerization. The prepared monodispersed polymers are after the drug attachment intended for enhanced anticancer therapy. This new approach significantly reduces the number of required synthetic steps and minimizes the consumption of organic solvents during the synthesis. As a result, highly defined linear, diblock, and starlike copolymers designed for pH-triggered drug activation/release in tumor tissue were formed in sufficient amounts for further physicochemical and biological studies. Within the synthesis, we also developed a new procedure for the selective deprotection of tert-butoxycarbonyl hydrazide and amine groups on hydrophilic HPMA copolymers, including the one-pot removal of polymer end groups. We studied and described in detail the kinetics and efficacy of the deprotection reaction. We believe the simplified synthetic approach facilitates the preparation of polymer conjugates bound by the pH-sensitive hydrazone bond and their application in tumor treatment.

• MeSH
• akrylamidy * chemie   MeSH
• antibiotika antitumorózní * chemie   MeSH
• doxorubicin * chemie   MeSH
• hydrofobní a hydrofilní interakce MeSH
• lidé MeSH
• nosiče léků * chemie   MeSH
• polymery * chemie   MeSH
• Check Tag
• lidé MeSH

Biodegradable nanoparticles based on stearic acid-modified poly(glycerol adipate) (PGAS) are promising carriers for drug delivery. In order to investigate the impact of the particle interface characteristics on the biological fate, PGAS nanoparticles are covalently and noncovalently coated with N-(2-hydroxypropyl) methacrylamide (HPMA) copolymers. HPMA copolymer-modified PGAS nanoparticles have similar particle sizes, but less negative zeta-potentials. Nanoparticles are double labeled with the fluorescent dyes DiR (noncovalently) and DYOMICS-676 (covalently bound to HPMA copolymer), and their biodistribution is investigated noninvasively by multispectral optical imaging. Both covalent and noncovalent coatings cause changes in the pharmacokinetics and biodistribution in healthy and tumor-bearing mice. In addition to the intended tumor accumulation, high signals of both fluorescent dyes are also observed in other organs, including liver, ovaries, adrenal glands, and bone. The unintended accumulation of nanocarriers needs further detailed and systematic investigations, especially with respect to the observed ovarian and adrenal gland accumulation.

• MeSH
• biologicky odbouratelné plasty chemie   MeSH
• buňky HT-29 MeSH
• fluorescenční barviva chemie   MeSH
• lidé MeSH
• methakryláty aplikace a dávkování   chemie   MeSH
• myši MeSH
• nádory farmakoterapie   genetika   patologie   MeSH
• nanočástice aplikace a dávkování   chemie   MeSH
• nosiče léků aplikace a dávkování   chemie   MeSH
• polyestery aplikace a dávkování   chemie   MeSH
• systémy cílené aplikace léků * MeSH
• tkáňová distribuce účinky léků   MeSH
• xenogenní modely - testy antitumorózní aktivity MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The delivery of nitric oxide (NO) specifically to solid tumours was explored in this study as a strategy to augment the passive accumulation of nanomedicines in tumours induced by the Enhanced Permeability and Retention (EPR) effect. An increase in accumulation was achieved by the binding of the chemical precursor of NO, based on an organic nitrate, to a water-soluble synthetic polymer drug carrier. Four structurally different N-(2-hydroxypropyl)methacrylamide (HPMA)-based polymer NO donors were synthesized. Depending on their chemical structure, two of these donors were hydrolytically stable, while two rapidly released the parent nitrate under acidic conditions, mimicking the intracellular environment. The polymer NO donors were shown to overcome the drawbacks related to low-molecular-weight NO releasing compounds, namely systemic toxicity, lack of site specificity, and fast blood clearance. The NO donors showed intracellular NO release upon incubation with tumour cells. In vivo, they potentiated the EPR effect, resulting in an increased accumulation of polymer-bound cytotoxic drug doxorubicin (Dox) in EL4 T-cell lymphoma inoculated in mice. This led to a better therapeutic outcome in the treatment of lymphoma with the high-molecular-weight polymer conjugates carrying Dox but not in the treatment with the free Dox. The localized augmentation of the EPR effect via the tumour-specific NO delivery system can be viewed as a promising strategy to potentiate polymer-based tumour therapy without increasing systemic toxicity.

• MeSH
• antibiotika antitumorózní aplikace a dávkování   MeSH
• buněčné linie MeSH
• donory oxidu dusnatého aplikace a dávkování   MeSH
• doxorubicin aplikace a dávkování   MeSH
• lidé MeSH
• lymfom T-buněčný farmakoterapie   MeSH
• myši inbrední C57BL MeSH
• nosiče léků aplikace a dávkování   MeSH
• polymery aplikace a dávkování   MeSH
• synergismus léků MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Ritonavir (RIT) is a widely used antiviral drug that acts as an HIV protease inhibitor with emerging potential in anticancer therapies. RIT causes inhibition of P-glycoprotein, which plays an important role in multidrug resistance (MDR) in cancer cells when overexpressed. Moreover, RIT causes mitochondrial dysfunction, leading to decreased ATP production and reduction of caveolin I expression, which can affect cell migration and tumor progression. To increase its direct antitumor activity, decrease severe side effects induced by the use of free RIT and improve its pharmacokinetics, ritonavir 5-methyl-4-oxohexanoate (RTV) was synthesized and conjugated to a tumor-targeted polymer carrier based on a N-(2-hydroxypropyl)methacrylamide (HPMA) copolymer. Here we demonstrated that polymer-bound RTV enhanced the internalization of polymer-RTV conjugates, differing in RTV content from 4 to 15 wt%, in HeLa cancer cells compared with polymer without RTV. The most efficient influx and internalization properties were determined for the polymer conjugate bearing 11 wt% of RTV. This conjugate was internalized by cells using both caveolin- and clathrin-dependent endocytic pathways in contrast to the RTV-free polymer, which was preferentially internalized only by clathrin-mediated endocytosis. Moreover, we found the co-localization of the RTV-conjugate with mitochondria and a significant decrease of ATP production in treated cells. Thus, the impact on mitochondrial mechanism can influence the function of ATP-dependent P-glycoprotein and also the cell viability of MDR cancer cells. Overall, this study demonstrated that the polymer-RTV conjugate is a promising polymer-based nanotherapeutic, suitable for antitumor combination therapy with other anticancer drugs and a potential mitochondrial drug delivery system.

• MeSH
• adenosintrifosfát biosyntéza   MeSH
• antitumorózní látky aplikace a dávkování   chemie   MeSH
• chemorezistence účinky léků   MeSH
• endocytóza účinky léků   MeSH
• HeLa buňky MeSH
• kaveolin 1 biosyntéza   genetika   MeSH
• klathrin farmakologie   MeSH
• koncentrace vodíkových iontů MeSH
• lidé MeSH
• methakryláty chemie   MeSH
• nanostruktury chemie   MeSH
• P-glykoprotein účinky léků   metabolismus   MeSH
• polymery MeSH
• ritonavir aplikace a dávkování   analogy a deriváty   chemie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

BACKGROUND: Human papillomavirus (HPV) type 16 infection is one of the most important etiological agents of oropharyngeal squamous cell carcinoma. Patients with HPV-associated carcinomas of the head and neck were reported to have a better clinical outcome than patients with HPV-negative tumors. Because HPV16 E6 and E7 oncoproteins are highly immunogenic and constitutively expressed, HPV-specific T cell immunity may play the key role in improving the prognosis of these patients. METHODS: Tumor-derived T cells were expanded in high levels of IL-2 and stimulated with HPV16 E6/E7 peptides in the presence or absence of anti-PD-1 monoclonal antibody nivolumab and soluble Tim-3. RESULTS: HPV16-specific tumor-infiltrating T cells were present in 73.1% of HPV-associated oropharyngeal tumors. HPV16 specific CD8+ TILs were able to produce IFNγ upon specific stimulation and predominantly expressed PD-1 but not Tim-3. Specific IFNγ production was further enhanced after a blockade of both PD-1 and Tim-3 pathways but not after a PD-1 blockade alone. Additionally, the specific stimulation of anti-HPV16 CD8+ T cells suppressed Tim-3 upregulation after the PD-1 blockade. CONCLUSION: Our data provide the rationale for combination cancer immunotherapy approaches, including the dual blockade of PD-1 and Tim-3 and, potentially, the use of HPV16-directed therapeutic vaccines.

• MeSH
• antigeny CD279 antagonisté a inhibitory   metabolismus   MeSH
• buněčný receptor 2 viru hepatitidy A metabolismus   MeSH
• CD8-pozitivní T-lymfocyty imunologie   MeSH
• cytokiny biosyntéza   MeSH
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• lidský papilomavirus 16 izolace a purifikace   MeSH
• nádory orofaryngu farmakoterapie   imunologie   metabolismus   virologie   MeSH
• nivolumab terapeutické užití   MeSH
• protinádorové látky imunologicky aktivní terapeutické užití   MeSH
• senioři MeSH
• tumor infiltrující lymfocyty imunologie   MeSH
• únik nádoru z imunitní kontroly MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH