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2.
Cancers (Basel) ; 14(17)2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-36077801

RESUMO

Background: The pancreatic ductal adenocarcinoma (PDAC) microenvironment is highly fibrotic and hypoxic, with poor immune cell infiltration. Recently, we showed that nucleolin (NCL) inhibition normalizes tumour vessels and impairs PDAC growth. Methods: Immunocompetent mouse models of PDAC were treated by the pseudopeptide N6L, which selectively inhibits NCL. Tumour-infiltrating immune cells and changes in the tumour microenvironment were analysed. Results: N6L reduced the proportion of regulatory T cells (Tregs) and myeloid-derived suppressor cells (MDSCs) and increased tumour-infiltrated T lymphocytes (TILs) with an activated phenotype. Low-dose anti-VEGFR2 treatment normalized PDAC vessels but did not modulate the immune suppressive microenvironment. RNAseq analysis of N6L-treated PDAC tumours revealed a reduction of cancer-associated fibroblast (CAF) expansion in vivo and in vitro. Notably, N6L treatment decreased IL-6 levels both in tumour tissues and in serum. Treating mPDAC by an antibody blocking IL-6 reduced the proportion of Tregs and MDSCs and increased the amount of TILs, thus mimicking the effects of N6L. Conclusions: These results demonstrate that NCL inhibition blocks the amplification of lymphoid and myeloid immunosuppressive cells and promotes T cell activation in PDAC through a new mechanism of action dependent on the direct inhibition of the tumoral stroma.

3.
J Colloid Interface Sci ; 618: 173-184, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35338924

RESUMO

HYPOTHESIS: We describe the possibility of using the same block copolymer carriers prepared by PISA for in situ drug encapsulation or drug conjugation. EXPERIMENTS: Block copolymers containing poly((ethylene glycol) methacrylate)-co-poly(pentafluorophenyl methacrylate)-b-poly(hydroxypropyl methacrylate) (P((PEGMA-co-PFBMA)-b-PHPMA)) were synthesized at 10 wt% using PISA. The first approach involved in situ Doxorubicin (DOX) loading during PISA, while the second exhibited surface functionalization of PISA-made vesicles with dual drug therapies, N-acetyl cysteine (NAC) and DOX using para-fluoro-thiol reaction (PFTR) and carbodiimide chemistry, respectively. Cytotoxicity, cell uptake, and cell apoptosis were assessed on MDA-MB-231 cell lines. FINDINGS: P((PEGMA-co-PFBMA)-b-PHPMA) nanocarriers were prepared, showing size and shape transformations from spheres, cylinders to raspberry-forming vesicles. DOX was readily loaded into NPs during PISA with relatively high encapsulation efficiency of 70 %, whereas the plain PISA-made vesicles could be functionalized with NAC and DOX at high yields. DOX-free NPs showed biocompatibility, whilst DOX-conjugated NPs imparted a concentration-dependent cytotoxicity, as well as an enhanced cell uptake compared to free DOX. The results demonstrated that the same PISA-derived self-assemblies enabled either in situ drug encapsulation, or post-polymerization surface engineering with useful functionalities upon tuning the macro-CTA block, thus holding promises for future drug delivery and biomedical applications.


Assuntos
Nanopartículas , Neoplasias , Doxorrubicina/metabolismo , Doxorrubicina/farmacologia , Portadores de Fármacos , Humanos , Metacrilatos , Micelas , Polimerização , Polímeros
4.
Cancers (Basel) ; 13(19)2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34638443

RESUMO

We previously showed that N6L, a pseudopeptide that targets nucleolin, impairs pancreatic ductal adenocarcinoma (PDAC) growth and normalizes tumor vessels in animal models. In this study, we analyzed the translatome of PDAC cells treated with N6L to identify the pathways that were either repressed or activated. We observed a strong decrease in global protein synthesis. However, about 6% of the mRNAs were enriched in the polysomes. We identified a 5'TOP motif in many of these mRNAs and demonstrated that a chimeric RNA bearing a 5'TOP motif was up-regulated by N6L. We demonstrated that N6L activates the mTOR pathway, which is required for the translation of these mRNAs. An inhibitory synergistic effect in PDAC cell lines, including patient-derived xenografts and tumor-derived organoids, was observed when N6L was combined with mTOR inhibitors. In conclusion, N6L reduces pancreatic cells proliferation, which then undergoes translational reprogramming through activation of the mTOR pathway. N6L and mTOR inhibitors act synergistically to inhibit the proliferation of PDAC and human PDX cell lines. This combotherapy of N6L and mTOR inhibitors could constitute a promising alternative to treat pancreatic cancer.

5.
Cancers (Basel) ; 13(17)2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34503252

RESUMO

The stroma is a relevant player in driving and supporting the progression of pancreatic ductal adenocarcinoma (PDAC), and a large body of evidence highlights its role in hindering the efficacy of current therapies. In fact, the dense extracellular matrix (ECM) characterizing this tumor acts as a natural physical barrier, impairing drug penetration. Consequently, all of the approaches combining stroma-targeting and anticancer therapy constitute an appealing option for improving drug penetration. Several strategies have been adopted in order to target the PDAC stroma, such as the depletion of ECM components and the targeting of cancer-associated fibroblasts (CAFs), which are responsible for the increased matrix deposition in cancer. Additionally, the leaky and collapsing blood vessels characterizing the tumor might be normalized, thus restoring blood perfusion and allowing drug penetration. Even though many stroma-targeting strategies have reported disappointing results in clinical trials, the ECM offers a wide range of potential therapeutic targets that are now being investigated. The dense ECM might be bypassed by implementing nanoparticle-based systems or by using mesenchymal stem cells as drug carriers. The present review aims to provide an overview of the principal mechanisms involved in the ECM remodeling and of new promising therapeutic strategies for PDAC.

6.
Cancers (Basel) ; 13(12)2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34203710

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive and resistant cancer with no available effective therapy. We have previously demonstrated that nucleolin targeting by N6L impairs tumor growth and normalizes tumor vessels in PDAC mouse models. Here, we investigated new pathways that are regulated by nucleolin in PDAC. We found that N6L and nucleolin interact with ß-catenin. We found that the Wnt/ß-catenin pathway is activated in PDAC and is necessary for tumor-derived 3D growth. N6L and nucleolin loss of function induced by siRNA inhibited Wnt pathway activation by preventing ß-catenin stabilization in PDAC cells. N6L also inhibited the growth and the activation of the Wnt/ß-catenin pathway in vivo in mice and in 3D cultures derived from MIA PaCa2 tumors. On the other hand, nucleolin overexpression increased ß-catenin stabilization. In conclusion, in this study, we identified ß-catenin as a new nucleolin interactor and suggest that the Wnt/ß-catenin pathway could be a new target of the nucleolin antagonist N6L in PDAC.

7.
Elife ; 102021 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-34106045

RESUMO

Only a fraction of cancer patients benefits from immune checkpoint inhibitors. This may be partly due to the dense extracellular matrix (ECM) that forms a barrier for T cells. Comparing five preclinical mouse tumor models with heterogeneous tumor microenvironments, we aimed to relate the rate of tumor stiffening with the remodeling of ECM architecture and to determine how these features affect intratumoral T cell migration. An ECM-targeted strategy, based on the inhibition of lysyl oxidase, was used. In vivo stiffness measurements were found to be strongly correlated with tumor growth and ECM crosslinking but negatively correlated with T cell migration. Interfering with collagen stabilization reduces ECM content and tumor stiffness leading to improved T cell migration and increased efficacy of anti-PD-1 blockade. This study highlights the rationale of mechanical characterizations in solid tumors to understand resistance to immunotherapy and of combining treatment strategies targeting the ECM with anti-PD-1 therapy.


Assuntos
Fenômenos Fisiológicos Celulares/efeitos dos fármacos , Colágeno/metabolismo , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Linfócitos T/metabolismo , Microambiente Tumoral/fisiologia , Animais , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Matriz Extracelular/metabolismo , Feminino , Inibidores de Checkpoint Imunológico/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias Experimentais , Proteína-Lisina 6-Oxidase/metabolismo
8.
Nanotechnology ; 32(32)2021 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-33892482

RESUMO

Conventional chemotherapy used against cancer is mostly limited due to their non-targeted nature, affecting normal tissue and causing undesirable toxic effects to the affected tissue. With the aim of improving these treatments both therapeutically and in terms of their safety, numerous studies are currently being carried out using nanoparticles (NPs) as a vector combining tumor targeting and carrying therapeutic tools. In this context, it appears that nucleolin, a molecule over-expressed on the surface of tumor cells, is an interesting therapeutic target. Several ligands, antagonists of nucleolin of various origins, such as AS1411, the F3 peptide and the multivalent pseudopeptide N6L have been developed and studied as therapeutic tools against cancer. Over the last ten years or so, numerous studies have been published demonstrating that these antagonists can be used as tumor targeting agents with NPs from various origins. Focusing on nucleolin ligands, the aim of this article is to review the literature recently published or under experimentation in our research team to evaluate the efficacy and future development of these tools as anti-tumor agents.


Assuntos
Antineoplásicos/uso terapêutico , Aptâmeros de Nucleotídeos/uso terapêutico , Neoplasias/tratamento farmacológico , Oligodesoxirribonucleotídeos/uso terapêutico , Fragmentos de Peptídeos/uso terapêutico , Peptídeos/uso terapêutico , Fosfoproteínas/antagonistas & inibidores , Proteínas de Ligação a RNA/antagonistas & inibidores , Antineoplásicos/química , Aptâmeros de Nucleotídeos/química , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/química , Expressão Gênica , Proteína HMGB2/genética , Proteína HMGB2/metabolismo , Humanos , Ligantes , Terapia de Alvo Molecular/métodos , Nanopartículas/administração & dosagem , Nanopartículas/química , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Oligodesoxirribonucleotídeos/química , Fragmentos de Peptídeos/química , Peptídeos/química , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Nanomedicina Teranóstica/métodos , Nucleolina
9.
Sci Rep ; 10(1): 19114, 2020 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-33154448

RESUMO

Heparan sulfate (HS) chains, covalently linked to heparan sulfate proteoglycans (HSPG), promote synaptic development and functions by connecting various synaptic adhesion proteins (AP). HS binding to AP could vary according to modifications of HS chains by different sulfotransferases. 3-O-sulfotransferases (Hs3sts) produce rare 3-O-sulfated HSs (3S-HSs), of poorly known functions in the nervous system. Here, we showed that a peptide known to block herpes simplex virus by interfering with 3S-HSs in vitro and in vivo (i.e. G2 peptide), specifically inhibited neural activity, reduced evoked glutamate release, and impaired synaptic assembly in hippocampal cell cultures. A role for 3S-HSs in promoting synaptic assembly and neural activity is consistent with the synaptic interactome of G2 peptide, and with the detection of Hs3sts and their products in synapses of cultured neurons and in synaptosomes prepared from developing brains. Our study suggests that 3S-HSs acting as receptors for herpesviruses might be important regulators of neuronal and synaptic development in vertebrates.


Assuntos
Proteoglicanas de Heparan Sulfato/metabolismo , Heparitina Sulfato/metabolismo , Hipocampo/metabolismo , Sulfotransferases/metabolismo , Sinapses/metabolismo , Animais , Células Cultivadas , Camundongos , Neurogênese/fisiologia , Neurônios/metabolismo
10.
Int J Pharm ; 590: 119930, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-33010394

RESUMO

Large-pore mesoporous silica (LPMS) microspheres with tunable pore size have received intensive interest in the field of drug delivery due to their high storage capacity and fast delivery rate of drugs. In this work, a facile salt-assisted spray-drying method has been developed to fabricate LPMS microspheres using continuous spray-drying of simple inorganic salts as pore templates and colloidal SiO2 nanoparticles as building blocks, followed by washing with water to remove the templates. More importantly, the porosity of the LPMS microspheres can be finely tuned by adjusting the furnace temperature and relative concentration of the salt to SiO2, which could lead to optimal pharmaceutical outcomes. Then, the biological roles of these LPMS microspheres were evaluated in antibacterial and cancer therapy. In this regard, rhodamine b as a probe was initially loaded inside the LPMS microspheres. The obtained particles not only showed high entrapment efficiency (up to 30%) and a pH-responsive drug release but also presented pore-size-controlled drug release performance. Then, in vitro antibacterial activities of multiple antibiotics, namely nalidixic acid, chloramphenicol, and ciprofloxacin, loaded in the LPMS particles were investigated against two pathogenic bacteria, Escherichia coli (Gram-negative) and Staphylococcus aureus (Gram-positive). The results indicated bacterial inhibition up to 70% and 20% in less than 2 h for Escherichia coli and Staphylococcus aureus, respectively. This inhibition of bacterial growth was accompanied by no bacterial regrowth within 30 h. Finally, the versatility of LPMS microspheres as drug carriers in pancreatic cancer treatment was explored. In this regard, a pro-apoptotic NCL antagonist agent (N6L) as an antitumor agent was successfully loaded onto LPMS microspheres. Interestingly, the resulting particles showed pore-size-dependent anticancer activity with inhibition of cancer cell growth up to 60%.


Assuntos
Neoplasias Pancreáticas , Dióxido de Silício , Antibacterianos/farmacologia , Composição de Medicamentos , Humanos , Microesferas , Neoplasias Pancreáticas/tratamento farmacológico , Tamanho da Partícula , Porosidade
11.
Nanomaterials (Basel) ; 10(6)2020 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-32466552

RESUMO

There is still a need for improving the treatment of breast cancer with doxorubicin (DOX). In this paper, we functionalized magnetic nanoparticles (MNPs) with DOX and studied the DOX-induced antitumor effects in breast cancer cells (BT474) in the presence of magnetic hyperthermia (43 °C, 1 h). We show that i) intratumoral application of DOX-functionalized MNPs (at least at a concentration of 9.6 nmol DOX/100 mm3 tumor volume) combined with magnetic hyperthermia favors tumor regression in vivo, and there is evidence for an increased effect compared to magnetic hyperthermia alone or to the intratumoral application of free DOX and ii) the presence of the pseudopeptide NucAnt (N6L) on the MNP surface might well be beneficial in its function as carrier for MNP internalization into breast cancer cells in vitro, which could further augment the possibility of the induction of intracellular heating spots and cell death in the future.

12.
FASEB J ; 34(4): 5851-5862, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32141122

RESUMO

Retinal vascular diseases (RVD) have been identified as a major cause of blindness worldwide. These pathologies, including the wet form of age-related macular degeneration, retinopathy of prematurity, and diabetic retinopathy are currently treated by intravitreal delivery of anti-vascular endothelial growth factor (VEGF) agents. However, repeated intravitreal injections can lead to ocular complications and resistance to these treatments. Thus, there is a need to find new targeted therapies. Nucleolin regulates the endothelial cell (EC) activation and angiogenesis. In previous studies, we designed a pseudopeptide, N6L, that binds the nucleolin and blocks the tumor angiogenesis. In this study, the effect of N6L was investigated in two experimental models of retinopathies including oxygen-induced retinopathy (OIR) and choroidal neovascularization (CNV). We found that in mouse OIR, intraperitoneal injection of N6L is delivered to activated ECs and induced a 50% reduction of pathological neovascularization. The anti-angiogenic effect of N6L has been tested in CNV model in which the systemic injection of N6L induced a 33% reduction of angiogenesis. This effect is comparable to those obtained with VEGF-trap, a standard of care drug for RVD. Interestingly, with preventive and curative treatments, neoangiogenesis is inhibited by 59%. Our results have potential interest in the development of new therapies targeting other molecules than VEGF for RVD.


Assuntos
Inibidores da Angiogênese/farmacologia , Neovascularização de Coroide/prevenção & controle , Peptídeos/farmacologia , Fosfoproteínas/antagonistas & inibidores , Proteínas de Ligação a RNA/antagonistas & inibidores , Doenças Retinianas/prevenção & controle , Animais , Proliferação de Células , Neovascularização de Coroide/etiologia , Neovascularização de Coroide/metabolismo , Neovascularização de Coroide/patologia , Modelos Animais de Doenças , Injeções Intravítreas , Camundongos , Camundongos Endogâmicos C57BL , Oxigênio/efeitos adversos , Fosforilação , Doenças Retinianas/etiologia , Doenças Retinianas/metabolismo , Doenças Retinianas/patologia , Nucleolina
13.
ACS Appl Mater Interfaces ; 12(6): 6885-6898, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-31967774

RESUMO

Hollow mesoporous silica microsphere (HMSM) particles are one of the most promising vehicles for efficient drug delivery owing to their large hollow interior cavity for drug loading and the permeable mesoporous shell for controlled drug release. Here, we report an easily controllable aerosol-based approach to produce HMSM particles by continuous spray-drying of colloidal silica nanoparticles and Eudragit/Triton X100 composite (EUT) nanospheres as templates, followed by template removal. Importantly, the internal structure of the hollow cavity and the external morphology and the porosity of the mesoporous shell can be tuned to a certain extent by adjusting the experimental conditions (i.e., silica to EUT mass ratio and particle size of silica nanoparticles) to optimize the drug loading capacity and the controlled-release properties. Then, the application of aerosol-synthesized HMSM particles in controlled drug delivery was investigated by loading amoxicillin as an antibiotic compound with high entrapment efficiency (up to 46%). Furthermore, to improve the biocompatibility of the amoxicillin-loaded HMSM particles, their surfaces were functionalized with poly(allylamine hydrochloride) and alginate as biocompatible polymers via the layer-by-layer assembly. The resulting particles were evaluated toward Escherichia coli (Gram-negative) bacteria and indicated the bacterial inhibition up to 90% in less than 2 h. Finally, we explored the versatility of HMSMs as drug carriers for pancreatic cancer treatment. Because the pH value of the extracellular medium in pancreatic tumors is lower than that of the healthy tissue, chitosan as a pH-sensitive gatekeeper was grafted to the HMSM surface and then loaded with a pro-apoptotic NCL antagonist agent (N6L) as an anticancer drug. The obtained particles exhibited pH-responsive drug releases and excellent anticancer activities with inhibition of cancer cell growth up to 60%.


Assuntos
Antibacterianos/química , Antineoplásicos/química , Preparações de Ação Retardada/química , Portadores de Fármacos/síntese química , Sistemas de Liberação de Medicamentos/instrumentação , Dióxido de Silício/química , Aerossóis/química , Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Preparações de Ação Retardada/farmacologia , Portadores de Fármacos/química , Escherichia coli/efeitos dos fármacos , Humanos , Microesferas , Nanopartículas/química , Tamanho da Partícula , Porosidade , Dióxido de Silício/síntese química
14.
J Cancer ; 11(3): 733-740, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31942196

RESUMO

Lung cancer is the most common cause of cancer death in the United States. The genome of non-small cell lung cancer (NSCLC), the most frequent lung cancer type, is strongly affected by Long Interspersed Nuclear Element (LINE1) insertions. Active LINE1s are repetitive DNA sequences that can amplify themselves in the genome utilizing a retrotransposition mechanism whereby LINE1 is copied via reverse transcription and inserted at target sites. ORF1p and ORF2p are LINE1 encoded proteins essential for LINE1 retrotransposition. LINE1s are silenced epigenetically in somatic tissues, and their reactivation has been associated with cancer pathogenesis. Here, we present evidence that nucleolin (NCL) regulates expression of LINE1-ORF1p (L1-ORF1p) in NSCLC cells. Genetic knockdown of NCL significantly inhibited expression of L1-ORF1p in various NSCLC cell lines. Treatment with the investigational NCL antagonist N6L ablated L1-ORF1p expression in all cell lines constitutively expressing L1-ORFp. N6L displayed a stronger antiproliferative activity in NSCLC tumor cell lines expressing the highest L1-ORF1p protein levels. Moreover, N6L treatment of nude mice bearing NSCLC tumor xenografts blocked L1-ORF1p expression and effectively inhibited tumor growth. These data indicate that L1-ORF1p expression is regulated by NCL and identify NCL as a novel promising target for pharmacological inhibition of LINE1.

15.
Arterioscler Thromb Vasc Biol ; 39(9): 1843-1858, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31315435

RESUMO

Objective Weibel-Palade bodies (WPBs) are endothelial cell (EC)-specific organelles formed by vWF (von Willebrand factor) polymerization and that contain the proangiogenic factor Ang-2 (angiopoietin-2). WPB exocytosis has been shown to be implicated for vascular repair and inflammatory responses. Here, we investigate the role of WPBs during angiogenesis and vessel stabilization. Approach and Results WPB density in ECs decreased at the angiogenic front of retinal vascular network during development and neovascularization compared with stable vessels. In vitro, VEGF (vascular endothelial growth factor) induced a VEGFR-2 (vascular endothelial growth factor receptor-2)-dependent exocytosis of WPBs that contain Ang-2 and consequently the secretion of vWF and Ang-2. Blocking VEGF-dependant WPB exocytosis and Ang-2 secretion promoted pericyte migration toward ECs. Pericyte migration was inhibited by adding recombinant Ang-2 or by silencing Ang-1 (angiopoietin-1) or Tie2 (angiopoietin-1 receptor) in pericytes. Consistently, in vivo anti-VEGF treatment induced accumulation of WPBs in retinal vessels because of the inhibition of WPB exocytosis and promoted the increase of pericyte coverage of retinal vessels during angiogenesis. In tumor angiogenesis, depletion of WPBs in vWF knockout tumor-bearing mice promoted an increase of tumor angiogenesis and a decrease of pericyte coverage of tumor vessels. By another approach, normalized tumor vessels had higher WPB density. Conclusions We demonstrate that WPB exocytosis and Ang-2 secretion are regulated during angiogenesis to limit pericyte coverage of remodeling vessels by disrupting Ang-1/Tie2 autocrine signaling in pericytes.


Assuntos
Neovascularização Patológica/fisiopatologia , Neovascularização Fisiológica/fisiologia , Pericitos/fisiologia , Corpos de Weibel-Palade/fisiologia , Angiopoietina-2/fisiologia , Animais , Células Cultivadas , Células Endoteliais/fisiologia , Exocitose , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias/irrigação sanguínea , Retina/fisiologia , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Fator A de Crescimento do Endotélio Vascular/fisiologia
16.
Nanomedicine ; 20: 101983, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30940505

RESUMO

In this paper we show that conjugation of magnetic nanoparticles (MNPs) with Gemcitabine and/or NucAnt (N6L) fostered their internalization into pancreatic tumor cells and that the coupling procedure did not alter the cytotoxic potential of the drugs. By treating tumor cells (BxPC3 and PANC-1) with the conjugated MNPs and magnetic hyperthermia (43 °C, 60 min), cell death was observed. The two pancreatic tumor cell lines showed different reactions against the combined therapy according to their intrinsic sensitivity against Gemcitabine (cell death, ROS production, ability to activate ERK 1/2 and JNK). Finally, tumors (e.g. 3 mL) could be effectively treated by using almost 4.2 × 105 times lower Gemcitabine doses compared to conventional therapies. Our data show that this combinatorial therapy might well play an important role in certain cell phenotypes with low readiness of ROS production. This would be of great significance in distinctly optimizing local pancreatic tumor treatments.


Assuntos
Hipertermia Induzida , Nanopartículas de Magnetita/química , Neoplasias Pancreáticas/patologia , Animais , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Antígeno Ki-67/metabolismo , Nanopartículas de Magnetita/ultraestrutura , Camundongos Nus , Peptídeos/farmacologia , Fenótipo , Fase S/efeitos dos fármacos , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Gencitabina
17.
ChemMedChem ; 13(3): 259-269, 2018 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-29314771

RESUMO

A member of the ribonuclease A superfamily, human angiogenin (hAng) is a potent angiogenic factor. Heteronuclear NMR spectroscopy combined with induced-fit docking revealed a dual binding mode for the most antiangiogenic compound of a series of ribofuranosyl pyrimidine nucleosides that strongly inhibit hAng's angiogenic activity in vivo. While modeling suggests the potential for simultaneous binding of the inhibitors at the active and cell-binding sites, NMR studies indicate greater affinity for the cell-binding site than for the active site. Additionally, molecular dynamics simulations at 100 ns confirmed the stability of binding at the cell-binding site with the predicted protein-ligand interactions, in excellent agreement with the NMR data. This is the first time that a nucleoside inhibitor is reported to completely inhibit the angiogenic activity of hAng in vivo by exerting dual inhibitory activity on hAng, blocking both the entrance of hAng into the cell and its ribonucleolytic activity.


Assuntos
Nucleosídeos de Pirimidina/química , Ribonuclease Pancreático/antagonistas & inibidores , Animais , Sítios de Ligação , Linhagem Celular , Embrião de Galinha , Membrana Corioalantoide/irrigação sanguínea , Membrana Corioalantoide/efeitos dos fármacos , Simulação por Computador , Humanos , Simulação de Dinâmica Molecular , Neovascularização Fisiológica/efeitos dos fármacos , Ressonância Magnética Nuclear Biomolecular , Relação Estrutura-Atividade
18.
J Cell Physiol ; 233(5): 4091-4105, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-28941284

RESUMO

Targeted anticancer therapies demand discovery of new cellular targets to be exploited for the delivery of toxic molecules and drugs. In this perspective, in the last few years, nucleolin has been identified as an interesting surface marker to be used for the therapy of glioblastoma. In this study, we investigated whether a synthetic antagonist of cell-surface nucleolin known as N6L, previously reported to decrease both tumor growth and tumor angiogenesis in several cancer cell lines, including glioblastoma cells, as well as endothelial cells proliferation, could be exploited to deliver a protein toxin (saporin) to glioblastoma cells. The pseudopeptide N6L cross-linked to saporin-S6 induced internalization of the toxin inside glioblastoma cancer cells. Our results in vitro demonstrated the effectiveness of this conjugate in inducing cell death, with an ID50 four orders of magnitude lower than that observed for free N6L. Furthermore, the preliminary in vivo study demonstrated efficiency in reducing the tumor mass in an orthotopic mouse model of glioblastoma.


Assuntos
Glioblastoma/tratamento farmacológico , Neovascularização Patológica/tratamento farmacológico , Peptídeos/farmacologia , Fosfoproteínas/farmacologia , Proteínas de Ligação a RNA/farmacologia , Animais , Linhagem Celular Tumoral , Membrana Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Glioblastoma/genética , Glioblastoma/patologia , Humanos , Camundongos , Terapia de Alvo Molecular , Neovascularização Patológica/patologia , Peptídeos/química , Fosfoproteínas/química , Proteínas de Ligação a RNA/química , Saporinas/química , Saporinas/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto , Nucleolina
19.
Oncotarget ; 8(52): 90108-90122, 2017 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-29163814

RESUMO

In this study, a novel anticancer reagent based on polyplexes nanoparticles was developed. These nanoparticles are obtained by mixing negatively charged polyelectrolytes with the antitumour cationically-charged pseudopeptide N6L. Using two in vivo experimental tumor pancreatic models based upon PANC-1 and mPDAC cells, we found that the antitumour activity of N6L is significantly raised via its incorporation in polyplexed nanoparticles. Study of the mechanism of action using affinity isolation and si-RNA experiments indicated that N6L-polyplexes are internalized through their interaction with nucleolin. In addition, using a very aggressive model of pancreatic cancer in which gemcitabine, a standard of care for this type of cancer, has a weak effect on tumour growth, we observed that N6L-polyplexes administration has a stronger efficacy than gemcitabine. Biodistribution studies carried out in tumour-bearing mice indicated that N6L-polyplexes localises in tumour tissue, in agreement with its antitumour effect. These results support the idea that N6L nanoparticles could develop into a promising strategy for the treatment of cancer, especially hard-to-treat pancreatic cancers.

20.
Cancer Res ; 76(24): 7181-7193, 2016 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-27754848

RESUMO

Pancreatic cancer is a highly aggressive tumor, mostly resistant to the standard treatments. Nucleolin is overexpressed in cancers and its inhibition impairs tumor growth. Herein, we showed that nucleolin was overexpressed in human specimens of pancreatic ductal adenocarcinoma (PDAC) and that the overall survival significantly increased in patients with low levels of nucleolin. The nucleolin antagonist N6L strongly impaired the growth of primary tumors and liver metastasis in an orthotopic mouse model of PDAC (mPDAC). Similar antitumor effect of N6L has been observed in a highly angiogenic mouse model of pancreatic neuroendocrine tumor RIP-Tag2. N6L significantly inhibited both human and mouse pancreatic cell proliferation and invasion. Notably, the analysis of tumor vasculature revealed a strong increase of pericyte coverage and vessel perfusion both in mPDAC and RIP-Tag2 tumors, in parallel to an inhibition of tumor hypoxia. Nucleolin inhibition directly affected endothelial cell (EC) activation and changed a proangiogenic signature. Among the vascular activators, nucleolin inhibition significantly decreased angiopoietin-2 (Ang-2) secretion and expression in ECs, in the tumor and in the plasma of mPDAC mice. As a consequence of the observed N6L-induced tumor vessel normalization, pre-treatment with N6L efficiently improved chemotherapeutic drug delivery and increased the antitumor properties of gemcitabine in PDAC mice. In conclusion, nucleolin inhibition is a new anti-pancreatic cancer therapeutic strategy that dually blocks tumor progression and normalizes tumor vasculature, improving the delivery and efficacy of chemotherapeutic drugs. Moreover, we unveiled Ang-2 as a potential target and suitable response biomarker for N6L treatment in pancreatic cancer. Cancer Res; 76(24); 7181-93. ©2016 AACR.


Assuntos
Carcinoma Ductal Pancreático/patologia , Neovascularização Patológica/patologia , Neoplasias Pancreáticas/patologia , Peptídeos/farmacologia , Fosfoproteínas/antagonistas & inibidores , Proteínas de Ligação a RNA/antagonistas & inibidores , Animais , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Progressão da Doença , Humanos , Camundongos , Análise Serial de Tecidos , Nucleolina
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