Závěrečná zpráva o řešení grantu Agentury pro zdravotnický výzkum MZ ČR
Nestr.
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
The study compared the physico-chemical and biological properties of a water-soluble star-like polymer nanomedicine with three micellar nanomedicines formed by self-assembly of amphiphilic copolymers differing in their hydrophobic part (statistical, block and thermosensitive block copolymers). All nanomedicines showed a pH-responsive release of the drug, independent on polymer structure. Significant penetration of all polymer nanomedicines into tumor cells in vitro was demonstrated, where the most pronounced effect was observed for statistical- or diblock copolymer-based micellar systems. Tumor accumulation in vivo was dependent on the stability of the nanomedicines in solution, being the highest for the star-like system, followed by the most stable micellar nanomedicines. The star-like polymer nanomedicine showed a superior therapeutic effect. Since the micellar systems exhibited slightly lower systemic toxicity, they may exhibit the same efficacy as the star-like soluble system when administered at equitoxic doses. In conclusion, treatment efficacy of studied nanomedicines was directly controlled by the drug pharmacokinetics, namely by their ability to circulate in the bloodstream for the time needed for effective accumulation in the tumor due to the enhanced permeability and retention (EPR) effect. Easy and scalable synthesis together with the direct reconstitution possibility for nanomedicine application made these nanomedicines excellent candidates for further clinical evaluation.
Small molecule Toll-like receptor-7 and -8 agonists (TLR-7/8a) can be used as vaccine adjuvants to induce CD8 T cell immunity but require formulations that prevent systemic toxicity and focus adjuvant activity in lymphoid tissues. Here, we covalently attached TLR-7/8a to polymers of varying composition, chain architecture and hydrodynamic behavior (∼300 nm submicrometer particles, ∼10 nm micelles and ∼4 nm flexible random coils) and evaluated how these parameters of polymer-TLR-7/8a conjugates impact adjuvant activity in vivo. Attachment of TLR-7/8a to any of the polymer compositions resulted in a nearly 10-fold reduction in systemic cytokines (toxicity). Moreover, both lymph node cytokine production and the magnitude of CD8 T cells induced against protein antigen increased with increasing polymer-TLR-7/8a hydrodynamic radius, with the submicrometer particle inducing the highest magnitude responses. Notably, CD8 T cell responses induced by polymer-TLR-7/8a were dependent on CCR2+ monocytes and IL-12, whereas responses by a small molecule TLR-7/8a that unexpectedly persisted in vaccine-site draining lymph nodes (T1/2 = 15 h) had less dependence on monocytes and IL-12 but required Type I IFNs. This study shows how modular properties of synthetic adjuvants can be chemically programmed to alter immunity in vivo through distinct immunological mechanisms.
- MeSH
- adjuvancia imunologická aplikace a dávkování chemie farmakologie MeSH
- aktivace lymfocytů * MeSH
- buněčné linie MeSH
- CD8-pozitivní T-lymfocyty účinky léků imunologie MeSH
- cytokiny metabolismus MeSH
- hydrodynamika MeSH
- kultivované buňky MeSH
- micely * MeSH
- myši inbrední C57BL MeSH
- myši MeSH
- toll-like receptor 7 agonisté MeSH
- toll-like receptor 8 agonisté MeSH
- vazba proteinů MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Intramural MeSH
Tumor-targeted photodynamic therapy (PDT) using polymeric photosensitizers is a promising therapeutic strategy for cancer treatment. In this study, we synthesized a pHPMA conjugated pyropheophorbide-a (P-PyF) as a cancer theranostic agent for PDT and photodynamic diagnostics (PDD). Pyropheophorbide-a has one carboxyl group which was conjugated to pHPMA via amide bond yielding the intended product with high purity. In aqueous solutions, P-PyF showed a mean particle size of ∼200 nm as it forms micelle which exhibited fluorescence quenching and thus very little singlet oxygen (1O2) production. In contrast, upon disruption of micelle strong fluorescence and 1O2 production were observed. In vitro study clearly showed the PDT effect of P-PyF. More potent 1O2 production and PDT effect were observed during irradiation at ∼420 nm, the maximal absorbance of pyropheophorbide-a, than irradiation at longer wavelength (i.e., ∼680 nm), suggesting selection of proper absorption light is essential for successful PDT. In vivo study showed high tumor accumulation of P-PyF compared with most of normal tissues due to the enhanced permeability and retention (EPR) effect, which resulting in superior antitumor effect under irradiation using normal xenon light source of endoscope, and clear tumor imaging profiles even in the metastatic lung cancer at 28 days after administration of P-PyF. On the contrary irradiation using long wavelength (i.e., ∼680 nm), the lowest Q-Band, exhibited remarkable tumor imaging effect with little autofluorescence of background. These findings strongly suggested P-PyF may be a potential candidate-drug for PDT/PDD, particularly using two different wavelength for treatment and detection/imaging, respectively.
- MeSH
- časové faktory MeSH
- chlorofyl aplikace a dávkování analogy a deriváty farmakokinetika MeSH
- fluorescence MeSH
- fotochemoterapie metody MeSH
- fotosenzibilizující látky aplikace a dávkování MeSH
- kyseliny polymethakrylové chemie MeSH
- micely MeSH
- myši inbrední BALB C MeSH
- myši inbrední C57BL MeSH
- myši MeSH
- nádory plic diagnóza farmakoterapie MeSH
- permeabilita MeSH
- polymery chemie MeSH
- teranostická nanomedicína metody MeSH
- tkáňová distribuce MeSH
- velikost částic MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Herein, the biodegradable micelle-forming amphiphilic N-(2-hydroxypropyl) methacrylamide (HPMA)-based polymer conjugates with the anticancer drug doxorubicin (Dox) designed for enhanced tumor accumulation were investigated, and the influence of their stability in the bloodstream on biodistribution, namely, tumor uptake, and in vivo antitumor efficacy were evaluated in detail. Dox was attached to the polymer carrier by a hydrazone bond enabling pH-controlled drug release. While the polymer-drug conjugates were stable in a buffer at pH 7.4 (mimicking bloodstream environment), Dox was released in a buffer under mild acidic conditions modeling the tumor microenvironment or cells. The amphiphilic polymer carriers differed in the structure of hydrophobic cholesterol derivative moieties bound to the HPMA copolymers via a hydrolyzable hydrazone bond, exhibiting different rates of micellar structure disintegration at various pH values. Considerable dependence of the studied polymer-drug conjugate biodistribution on the stability of the micellar structure was observed in neutral, bloodstream-mimicking, environment, showing that a faster rate of the micelle disintegration in pH 7.4 increased the conjugate blood clearance, decreased tumor accumulation, and significantly reduced the tumor:blood and tumor:muscle ratios. Similarly, the final therapeutic outcome was strongly affected by the stability of the micellar structure because the most stable micellar conjugate showed an almost similar therapeutic outcome as the water-soluble, nondegradable, high-molecular-weight starlike HPMA copolymer-Dox conjugate, which was highly efficient in the treatment of solid tumors in mice. Based on the results, we conclude that the bloodstream stability of micellar polymer-anticancer drug conjugates, in addition to their low side toxicity, is a crucial parameter for their efficient solid tumor accumulation and high in vivo antitumor activity.
- MeSH
- antitumorózní látky chemie farmakokinetika terapeutické užití MeSH
- doxorubicin chemie farmakokinetika terapeutické užití MeSH
- hydrofobní a hydrofilní interakce MeSH
- koncentrace vodíkových iontů MeSH
- lymfom krev farmakoterapie MeSH
- micely MeSH
- myši inbrední C57BL MeSH
- myši MeSH
- nosiče léků chemie MeSH
- polymery chemie MeSH
- uvolňování léčiv MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
New amphiphilic diblock polymer nanotherapeutics serving simultaneously as a drug delivery system and an inhibitor of multidrug resistance were designed, synthesized, and evaluated for their physico-chemical and biological characteristics. The amphiphilic character of the diblock polymer, containing a hydrophilic block based on the N-(2-hydroxypropyl)methacrylamide copolymer and a hydrophobic poly(propylene oxide) block (PPO), caused self-assembly into polymer micelles with an increased hydrodynamic radius (Rhof approximately 15nm) in aqueous solutions. Doxorubicin (Dox), as a cytostatic drug, was bound to the diblock polymer through a pH-sensitive hydrazone bond, enabling prolonged circulation in blood, the delivery of Dox into a solid tumor and the subsequent stimuli-sensitive controlled release within the tumor mass and tumor cells at a decreased pH. The applicability of micellar nanotherapeutics as drug carriers was confirmed by an in vivo evaluation using EL4 lymphoma-bearing C57BL/6 mice. We observed significantly higher accumulation of micellar conjugates in a solid tumor because of the EPR effect compared with similar polymer-drug conjugates that do not form micellar structures or with the parent free drug. In addition, highly increased anti-tumor efficacy of the micellar polymer nanotherapeutics, even at a sub-optimal dose, was observed. The presence of PPO in the structure of the diblock polymer ensured, during in vitro tests on human and mouse drug-sensitive and resistant cancer cell lines, the inhibition of P-glycoprotein, one of the most frequently expressed ATP-dependent efflux pump that causes multidrug resistance. In addition, we observed highly increased rate of the uptake of the diblock polymer nanotherapeutics within the cells. We suppose that combination of unique properties based on MDR inhibition, stimuli sensitiveness (pH sensitive activation of drug), improved pharmacokinetics and increased uptake into the cells made the described polymer micelle a good candidate for investigation as potential drug delivery system.
- MeSH
- akrylamidy aplikace a dávkování chemie farmakokinetika terapeutické užití MeSH
- antibiotika antitumorózní aplikace a dávkování chemie farmakokinetika terapeutické užití MeSH
- chemorezistence účinky léků MeSH
- doxorubicin aplikace a dávkování chemie farmakokinetika terapeutické užití MeSH
- hydrofobní a hydrofilní interakce MeSH
- lidé MeSH
- micely * MeSH
- mnohočetná léková rezistence účinky léků MeSH
- myši inbrední C57BL MeSH
- myši MeSH
- nádorové buněčné linie MeSH
- nádory farmakoterapie metabolismus patologie MeSH
- nosiče léků aplikace a dávkování chemie farmakokinetika terapeutické užití MeSH
- polymery aplikace a dávkování chemie farmakokinetika terapeutické užití MeSH
- propylenglykoly aplikace a dávkování chemie farmakokinetika terapeutické užití MeSH
- tumor burden účinky léků MeSH
- uvolňování léčiv MeSH
- viabilita buněk účinky léků MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Here, we present the synthesis, physicochemical, and preliminary biological characterization of micellar polymer-betulinic acid (BA) conjugates based on N-(2-hydroxypropyl)methacrylamide (HPMA) copolymer carriers, enabling the controlled release of cytotoxic BA derivatives in solid tumors or tumor cells. Various HPMA copolymer conjugates differing in the structure of the spacer between the drug and the carrier were synthesized, all designed for pH-triggered drug release in tumor tissue or tumor cells. The high molecular weight of the micellar conjugates should improve the uptake of the drug in solid tumors due to the Enhanced permeability and retention (EPR) effect. Nevertheless, only the conjugate containing BA with methylated carboxyl groups enabled pH-dependent controlled release in vitro. Moreover, drug release led to the disassembly of the micellar structure, which facilitated elimination of the water-soluble HPMA copolymer carrier from the body by renal filtration. The methylated BA derivative and its polymer conjugate exhibited high cytostatic activity against DLD-1, HT-29, and HeLa carcinoma cell lines and enhanced tumor accumulation in HT-29 xenograft in mice.
- MeSH
- biologicky odbouratelné plasty chemie MeSH
- doxorubicin aplikace a dávkování chemie MeSH
- lidé MeSH
- methakryláty aplikace a dávkování chemie MeSH
- micely MeSH
- myši MeSH
- nádorové buněčné linie MeSH
- nádory farmakoterapie MeSH
- nosiče léků aplikace a dávkování chemie MeSH
- polymery aplikace a dávkování chemie MeSH
- proliferace buněk účinky léků MeSH
- triterpeny aplikace a dávkování chemie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
To optimally exploit the potential of (tumor-) targeted nanomedicines, platform technologies are needed in which physicochemical and pharmaceutical properties can be tailored according to specific medical needs and applications. We here systematically customized the properties of core-crosslinked polymeric micelles (CCPM). The micelles were based on mPEG-b-pHPMAmLacn(i.e. methoxy poly(ethylene glycol)-b-poly[N-(2-hydroxypropyl) methacrylamide-lactate]), similar to the block copolymer composition employed in CriPec® docetaxel, which is currently in phase I clinical trials. The CCPM platform was tailored with regard to size (30 to 100nm), nanocarrier degradation (1month to 1year) and drug release kinetics (10 to 90% in 1week). This was achieved by modulating the molecular weight of the block copolymer, the type and density of the crosslinking agent, and the hydrolytic sensitivity of the drug linkage, respectively. The high flexibility of CCPM facilitates the development of nanomedicinal products for specific therapeutic applications.
In this work, design and synthesis of high-molecular-weight N-(2-hydroxypropyl)methacrylamide-based polymer drug delivery systems tailored for cancer therapy is summarized. Moreover, the influence of their architecture on tumor accumulation and in vivo anti-cancer efficacy is discussed. Mainly, the high-molecular-weight delivery systems, such as branched, grafted, multi-block, star-like or micellar systems, with molecular weights greater than the renal threshold are discussed and reviewed in detail.
An effective chemotherapy for neoplastic diseases requires the use of drugs that can reach the site of action at a therapeutically efficacious concentration and maintain it at a constant level over a sufficient period of time with minimal side effects. Currently, conjugates of high-molecular-weight hydrophilic polymers or biocompatible nanoparticles with stimuli-releasable anticancer drugs are considered to be some of the most promising systems capable of fulfilling these criteria. In this work, conjugates of thermoresponsive diblock copolymers with the covalently bound cancerostatic drug pirarubicin (PIR) were synthesized as a reversible micelle-forming drug delivery system combining the benefits of the above-mentioned carriers. The diblock copolymer carriers were composed of hydrophilic poly[N-(2-hydroxypropyl)methacrylamide]-based block containing a small amount (∼ 5 mol %) of comonomer units with reactive hydrazide groups and a thermoresponsive poly[2-(2-methoxyethoxy)ethyl methacrylate] block. PIR was attached to the hydrophilic block of the copolymer through the pH-sensitive hydrazone bond designed to be stable in the bloodstream at pH 7.4 but to be degraded in an intratumoral/intracellular environment at pH 5-6. The temperature-induced conformation change of the thermoresponsive block (coil-globule transition), followed by self-assembly of the copolymer into a micellar structure, was controlled by the thermoresponsive block length and PIR content. The cytotoxicity and intracellular transport of the conjugates as well as the release of PIR from the conjugates inside the cells, followed by its accumulation in the cell nuclei, were evaluated in vitro using human colon adenocarcinoma (DLD-1) cell lines. It was demonstrated that the studied conjugates have a great potential to become efficacious in vivo pharmaceuticals.
- MeSH
- antitumorózní látky aplikace a dávkování chemie MeSH
- doxorubicin aplikace a dávkování analogy a deriváty chemie MeSH
- hydrofobní a hydrofilní interakce MeSH
- koncentrace vodíkových iontů MeSH
- lidé MeSH
- micely MeSH
- nádorové buněčné linie MeSH
- nádory farmakoterapie MeSH
- nanočástice aplikace a dávkování chemie MeSH
- polymery aplikace a dávkování chemie MeSH
- systémy cílené aplikace léků * MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
