Antibody-mediated targeting is an efficient strategy to enhance the specificity and selectivity of polymer nanomedicines towards the target site, typically a tumor. However, direct covalent coupling of an antibody with a polymer usually results in a partial damage of the antibody binding site accompanied with a compromised biological activity. Here, an original solution based on well-defined non-covalent interactions between tris-nitrilotriacetic acid (trisNTA) and hexahistidine (His-tag) groups, purposefully introduced to the structure of each macromolecule, is described. Specifically, trisNTA groups were attached along the chains of a hydrophilic statistical copolymer based on N-(2-hydroxypropyl)methacrylamide (HPMA), and at the end or along the chains of thermo-responsive di-block copolymers based on N-isopropylmethacrylamide (NIPMAM) and HPMA; His-tag was incorporated to the structure of a recombinant single chain fragment of an anti-GD2 monoclonal antibody (scFv-GD2). Static and dynamic light scattering analyses confirmed that mixing of polymer with scFv-GD2 led to the formation of polymer/scFv-GD2 complexes; those prepared from thermo-responsive polymers formed stable micelles at 37 °C. Flow cytometry and fluorescence microscopy clearly demonstrated antigen-specific binding of the prepared complexes to GD2 positive murine T-cell lymphoma cells EL-4 and human neuroblastoma cells UKF-NB3, while no interaction with GD2 negative murine fibroblast cells NIH-3T3 was observed. These non-covalent polymer protein complexes represent a new generation of highly specific actively targeted polymer therapeutics or diagnostics.

• MeSH
• kyselina nitrilotrioctová MeSH
• lékové transportní systémy metody   MeSH
• lidé MeSH
• myši MeSH
• nádory * MeSH
• polymery * chemie   MeSH
• rekombinantní proteiny MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

BACKGROUND: Nanomaterials are at the leading edge of the rapidly developing field of nanotechnology. Magnetic nanoparticles for cancer therapy and diagnosis have been developed on the basis of their unique physico-chemical properties not present in other materials. Their versatility is widely exploited in such diverse techniques as cell and macromolecule separation and purification, immunoassays, targeted drug delivery, controlled material release, electromagnetic hyperthermia, gene therapy, or magnetic resonance imaging. In this review we concentrate on the physical principles of magnetic drug targeting and biomedical applications of this technique. METHODS AND RESULTS: We examined several databases, PubMed, ISI Web of Knowledge, and Scopus, for the period 1985-2009, with specific attention to studies that used targeting of magnetic nanoparticles especially in the therapy and diagnostics of tumors. We have also presented several of our own results on theoretical simulations of magnetic particle motion in external magnetic field. CONCLUSIONS: We found growing number of published papers in this field of nanomedicine, showing the almost unlimited potential of magnetic nanoparticles in the field of experimental and clinical oncology.

• MeSH
• analýza metodou konečných prvků MeSH
• financování organizované MeSH
• kovové nanočástice MeSH
• lékové transportní systémy MeSH
• magnetismus MeSH
• nádory diagnóza   farmakoterapie   MeSH
• nanočástice MeSH
• nanomedicína MeSH
• počítačová simulace MeSH
• železité sloučeniny diagnostické užití   terapeutické užití   MeSH
• Publikační typ
• přehledy MeSH

BACKGROUND: Galectin-3 (Gal-3) is a promising target in cancer therapy with a high therapeutic potential due to its abundant localization within the tumor tissue and its involvement in tumor development and proliferation. Potential clinical application of Gal-3-targeted inhibitors is often complicated by their insufficient selectivity or low biocompatibility. Nanomaterials based on N-(2-hydroxypropyl)methacrylamide (HPMA) nanocarrier are attractive for in vivo application due to their good water solubility and lack of toxicity and immunogenicity. Their conjugation with tailored carbohydrate ligands can yield specific glyconanomaterials applicable for targeting biomedicinally relevant lectins like Gal-3. RESULTS: In the present study we describe the synthesis and the structure-affinity relationship study of novel Gal-3-targeted glyconanomaterials, based on hydrophilic HPMA nanocarriers. HPMA nanocarriers decorated with varying amounts of Gal-3 specific epitope GalNAcβ1,4GlcNAc (LacdiNAc) were analyzed in a competitive ELISA-type assay and their binding kinetics was described by surface plasmon resonance. We showed the impact of various linker types and epitope distribution on the binding affinity to Gal-3. The synthesis of specific functionalized LacdiNAc epitopes was accomplished under the catalysis by mutant β-N-acetylhexosaminidases. The glycans were conjugated to statistic HPMA copolymer precursors through diverse linkers in a defined pattern and density using Cu(I)-catalyzed azide-alkyne cycloaddition. The resulting water-soluble and structurally flexible synthetic glyconanomaterials exhibited affinity to Gal-3 in low μM range. CONCLUSIONS: The results of this study reveal the relation between the linker structure, glycan distribution and the affinity of the glycopolymer nanomaterial to Gal-3. They pave the way to specific biomedicinal glyconanomaterials that target Gal-3 as a therapeutic goal in cancerogenesis and other disorders.

• MeSH
• akrylamidy chemie   metabolismus   MeSH
• galektin 3 metabolismus   MeSH
• glykokonjugáty chemie   metabolismus   MeSH
• lékové transportní systémy * MeSH
• lidé MeSH
• nanostruktury chemie   MeSH
• nosiče léků chemie   metabolismus   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

Myeloid cells comprise a major component of the tumor microenvironment (TME) that promotes tumor growth and immune evasion. By employing a small-molecule inhibitor of glutamine metabolism, not only were we able to inhibit tumor growth, but we markedly inhibited the generation and recruitment of myeloid-derived suppressor cells (MDSCs). Targeting tumor glutamine metabolism led to a decrease in CSF3 and hence recruitment of MDSCs as well as immunogenic cell death, leading to an increase in inflammatory tumor-associated macrophages (TAMs). Alternatively, inhibiting glutamine metabolism of the MDSCs themselves led to activation-induced cell death and conversion of MDSCs to inflammatory macrophages. Surprisingly, blocking glutamine metabolism also inhibited IDO expression of both the tumor and myeloid-derived cells, leading to a marked decrease in kynurenine levels. This in turn inhibited the development of metastasis and further enhanced antitumor immunity. Indeed, targeting glutamine metabolism rendered checkpoint blockade-resistant tumors susceptible to immunotherapy. Overall, our studies define an intimate interplay between the unique metabolism of tumors and the metabolism of suppressive immune cells.

• MeSH
• buněčná imunita * MeSH
• experimentální nádory imunologie   patologie   terapie   MeSH
• glutamin imunologie   MeSH
• imunoterapie MeSH
• makrofágy imunologie   patologie   MeSH
• myeloidní supresorové buňky imunologie   patologie   MeSH
• myši inbrední BALB C MeSH
• myši knockoutované MeSH
• myši MeSH
• nádorové mikroprostředí imunologie   MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH

Starting from benzyl 30-oxobetulinate and 30-oxobetulin diacetate, substituted dienes were synthesized and subjected to Diels-Alder reaction, yielding a variety of triterpenoid phthalates, phthalimides, and related derivatives. A total of 55 new compounds were prepared and tested for in vitro cytotoxic activity against eight cancer cell lines and two non-cancerous cell lines. Four compounds with IC50 values of 5 μM or lower were selected for further investigation. These compounds induced apoptosis in CCRF-CEM cells in a concentration-dependent manner, accompanied by mitochondrial depolarization and altered expression of key proteins involved in mitochondrial apoptosis. The compounds also disrupted DNA replication and transcriptional activity. Modulation of key proliferation pathways, including PI3K/Akt and STAT3, further supported the antiproliferative potential of these derivatives. Considering their high cytotoxicity and antiproliferative activity in CCRF-CEM cells, compounds 19, 26, 28, and 30 have been identified as promising candidates for further development.

• MeSH
• apoptóza * účinky léků   MeSH
• ftalimidy * farmakologie   chemie   chemická syntéza   MeSH
• lidé MeSH
• mitochondrie * účinky léků   metabolismus   MeSH
• molekulární struktura MeSH
• nádorové buněčné linie MeSH
• proliferace buněk * účinky léků   MeSH
• protinádorové látky * farmakologie   chemie   chemická syntéza   MeSH
• screeningové testy protinádorových léčiv * MeSH
• triterpeny * farmakologie   chemie   chemická syntéza   MeSH
• vztah mezi dávkou a účinkem léčiva MeSH
• vztahy mezi strukturou a aktivitou MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

BACKGROUND: Nanoparticle-based systems are promising for the development of imaging and therapeutic agents. The main advantage of nanoparticles over traditional systems lies in the possibility of loading multiple functionalities onto a single molecule, which are useful for therapeutic and/or diagnostic purposes. These functionalities include targeting moieties which are able to recognize receptors overexpressed by specific cells and tissues. However, targeted delivery of nanoparticles requires an accurate system design. We present here a rationally designed, genetically engineered, and chemically modified protein-based nanoplatform for cell/tissue-specific targeting. METHODS: Our nanoparticle constructs were based on the heavy chain of the human protein ferritin (HFt), a highly symmetrical assembly of 24 subunits enclosing a hollow cavity. HFt-based nanoparticles were produced using both genetic engineering and chemical functionalization methods to impart several functionalities, ie, the α-melanocyte-stimulating hormone peptide as a melanoma-targeting moiety, stabilizing and HFt-masking polyethylene glycol molecules, rhodamine fluorophores, and magnetic resonance imaging agents. The constructs produced were extensively characterized by a number of physicochemical techniques, and assayed for selective melanoma-targeting in vitro and in vivo. RESULTS: Our HFt-based nanoparticle constructs functionalized with the α-melanocyte-stimulating hormone peptide moiety and polyethylene glycol molecules were specifically taken up by melanoma cells but not by other cancer cell types in vitro. Moreover, experiments in melanoma-bearing mice indicate that these constructs have an excellent tumor-targeting profile and a long circulation time in vivo. CONCLUSION: By masking human HFt with polyethylene glycol and targeting it with an α-melanocyte-stimulating hormone peptide, we developed an HFt-based melanoma-targeting nanoplatform for application in melanoma diagnosis and treatment. These results could be of general interest, because the same strategy can be exploited to develop ad hoc nanoplatforms for specific delivery towards any cell/tissue type for which a suitable targeting moiety is available.

• MeSH
• alfa-MSH chemie   diagnostické užití   MeSH
• apoferritiny chemie   MeSH
• buňky HT-29 MeSH
• fluorescenční barviva chemie   diagnostické užití   MeSH
• konfokální mikroskopie MeSH
• lékové transportní systémy MeSH
• lidé MeSH
• magnetická rezonanční tomografie MeSH
• magnetické nanočástice chemie   diagnostické užití   ultrastruktura   MeSH
• melanom experimentální diagnóza   MeSH
• myši inbrední C57BL MeSH
• myši MeSH
• nanomedicína MeSH
• nanotechnologie MeSH
• polyethylenglykoly chemie   MeSH
• rekombinantní proteiny chemie   MeSH
• stabilita proteinů MeSH
• transmisní elektronová mikroskopie MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The conserved MRE11-RAD50-NBS1 (MRN) complex is an important sensor of DNA double-strand breaks (DSBs) and facilitates DNA repair by homologous recombination (HR) and end joining. Here, we identify NBS1 as a target of cyclin-dependent kinase (CDK) phosphorylation. We show that NBS1 serine 432 phosphorylation occurs in the S, G2 and M phases of the cell cycle and requires CDK activity. This modification stimulates MRN-dependent conversion of DSBs into structures that are substrates for repair by HR. Impairment of NBS1 phosphorylation not only negatively affects DSB repair by HR, but also prevents resumption of DNA replication after replication-fork stalling. Thus, CDK-mediated NBS1 phosphorylation defines a molecular switch that controls the choice of repair mode for DSBs.

• MeSH
• DNA vazebné proteiny chemie   MeSH
• dvouřetězcové zlomy DNA MeSH
• enzymy opravy DNA chemie   MeSH
• homologní rekombinace * MeSH
• jaderné proteiny * genetika   metabolismus   MeSH
• lidé MeSH
• mutageneze cílená MeSH
• nádorové buněčné linie MeSH
• oprava DNA MeSH
• proteinkinasa CDC2 * chemie   metabolismus   MeSH
• proteiny buněčného cyklu * chemie   genetika   metabolismus   MeSH
• replikace DNA * MeSH
• štěpení DNA * MeSH
• substituce aminokyselin MeSH
• Check Tag
• lidé MeSH

Adoptive cell therapy (ACT) is becoming a prominent alternative therapeutic treatment for cancer patients relapsing on traditional therapies. In parallel, antibodies targeting immune checkpoint molecules, such as cytotoxic-T-lymphocyte-associated antigen 4 (CTLA-4) and cell death protein 1 pathway (PD-1), are rapidly being approved for multiple cancer types, including as first line therapy for PD-L1-expressing non-small-cell lung cancer. The combination of ACT and checkpoint blockade could substantially boost the efficacy of ACT. In this study, we generated a novel self-delivering small interfering RNA (siRNA) (sdRNA) that knocked down PD-1 expression on healthy donor T cells as well as patient-derived tumor-infiltrating lymphocytes (TIL). We have developed an alternative chemical modification of RNA backbone for improved stability and increased efficacy. Our results show that T cells treated with sdRNA specific for PD-1 had increased interferon γ (IFN-γ) secreting capacity and that this modality of gene expression interference could be utilized in our rapid expansion protocol for production of TIL for therapy. TIL expanded in the presence of PD-1-specific sdRNA performed with increased functionality against autologous tumor as compared to control TIL. This method of introducing RNAi into T cells to modify the expression of proteins could easily be adopted into any ACT protocol and will lead to the exploration of new combination therapies.

• MeSH
• antigeny CD279 genetika   metabolismus   MeSH
• buněčná a tkáňová terapie metody   MeSH
• HeLa buňky MeSH
• imunoterapie adoptivní metody   MeSH
• interferon gama genetika   metabolismus   MeSH
• lidé MeSH
• melanom imunologie   metabolismus   terapie   MeSH
• nádory plic imunologie   metabolismus   terapie   MeSH
• průtoková cytometrie MeSH
• RNA interference fyziologie   MeSH
• T-lymfocyty metabolismus   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH

BACKGROUND: Historically, metastatic colorectal carcinoma was regarded as a tumor that is relatively resistant to cytotoxic-agents. Due to the limited number of treatment options, methods have been investigated to enhance selectivity. One method for enhancing selectivity is anatomical targeting, including hepatic arterial infusion (HAI). METHODS: A comprehensive review of the literature. RESULTS: Early studies with HAI used fluoropyrimidines, 5-fluorouracil or floxuridine. Several randomized trials comparing the HAI of fluoropyrimidines with systemic administration of fluoropyrimidines or best supportive care that were conducted in the 1980s and early 1990s demonstrated a superior objective response rate, but usually not a prolongation of survival in patients treated with HAI. The current standard of first line systemic chemotherapy of metastatic colorectal carcinoma is combination chemotherapy (fluoropyrimidines, oxaliplatin and/or irinotecan) administered with targeted agents. A number of trials have reported promising activity of the HAI of oxaliplatin and/or irinotecan with fluoropyrimidines, but only pilot studies are available for the combination of HAI of cytotoxic agents with targeted drugs. Factors that limit the effectiveness and utilization of HAI include catheter or port system related complications, the presence of extrahepatic metastases, or increased risk of hepatic toxicity. CONCLUSIONS: HAI could be considered in clinical practice in different settings, including patients after liver resection, as second line therapy in patients failing standard front line regimens and as neodjuvant therapy to convert to resectability. Future studies should specifically concentrate on identifying regimens that would result in increased cure rates in patients with isolated hepatic metastases. For this reason, exploiting anatomical selectivity may still be a useful approach, even in the era of targeted therapy.

• MeSH
• arteria hepatica MeSH
• chemoterapie nádorů pomocí regionální perfúze MeSH
• cílená molekulární terapie MeSH
• intraarteriální infuze MeSH
• kolorektální nádory patologie   MeSH
• lidé MeSH
• nádory jater farmakoterapie   sekundární   MeSH
• protinádorové látky aplikace a dávkování   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH

In the complex network of cellular physiology, the maintenance of cellular proteostasis emerges as a critical factor for cell survival, particularly under stress conditions. This homeostasis is largely governed by a sophisticated network of molecular chaperones and co-chaperones, among which Bcl-2-associated athanogene 3 (BAG3), able to interact with the ATPase domain of Heat Shock Protein 70 (HSP70), plays a pivotal role. The BAG3-HSP70 functional module is not only essential for cellular homeostasis but is also involved in the pathogenesis of various diseases, including cancer, neurodegenerative disorders, and cardiac dysfunction, making it an attractive target for therapeutic intervention. Inspired by our continuous interest in the development of new chemical platforms able to interfere with BAG3 protein, herein we report the discovery of compound 16, the first-in-class BAG3/HSP70 dual modulator, obtained by combining the multicomponent Ugi reaction with the alkyne-azide Huisgen procedure in a sequential tandem reaction approach. Through a combination of biophysical analysis, biochemical assays, and cell-based studies, we elucidated the mechanism of action of this inhibitor and assessed its potential as a therapeutic agent. Hence, this study can open new avenues for the development of novel anticancer strategies that leverage the simultaneous disruption of multiple chaperone pathways.

• MeSH
• adaptorové proteiny signální transdukční * metabolismus   antagonisté a inhibitory   MeSH
• lidé MeSH
• molekulární chaperony metabolismus   antagonisté a inhibitory   chemie   MeSH
• molekulární struktura MeSH
• nádorové buněčné linie MeSH
• proliferace buněk účinky léků   MeSH
• proteiny regulující apoptózu * metabolismus   antagonisté a inhibitory   MeSH
• proteiny tepelného šoku HSP70 * antagonisté a inhibitory   metabolismus   MeSH
• protinádorové látky * farmakologie   chemie   chemická syntéza   MeSH
• screeningové testy protinádorových léčiv MeSH
• vztah mezi dávkou a účinkem léčiva MeSH
• vztahy mezi strukturou a aktivitou MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH