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1.
Bioorg Chem ; 130: 106200, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36332316

RESUMO

Targeting vascular endothelial growth factor receptor (VEFGR) and its co-receptor neuropilin-1 (NRP-1) is an interesting vascular strategy. tLyp-1 is a tumor-homing and penetrating peptide of 7 amino acids (CGNKRTR). It is a truncated form of Lyp-1 (CGNKRTRGC), which is known to target NRP-1 receptor, with high affinity and specificity. It is mediated by endocytosis via C-end rule (CendR) internalization pathway. The aim of this study is to evaluate the importance of each amino acid in the tLyp-1 sequence through alanine-scanning (Ala-scan) technique, during which each of the amino acid in the sequence was systematically replaced by alanine to produce 7 different analogues. In silico approach through molecular docking and molecular dynamics are employed to understand the interaction between the peptide and its analogues with the NRP-1 receptor, followed by in vitro ligand binding assay study. The C-terminal Arg is crucial in the interaction of tLyp-1 with NRP-1 receptor. Substituting this residue dramatically reduces the affinity of this peptide which is clearly seen in this study. Lys-4 is also important in the interaction, which is confirmed via the in vitro study and the MM-PBSA analysis. The finding in this study supports the CendR, in which the presence of R/K-XX-R/K motif is essential in the binding of a ligand with NRP-1 receptor. This presented work will serve as a guide in the future work pertaining the development of active targeting agent towards NRP-1 receptor.


Assuntos
Neuropilina-1 , Fator A de Crescimento do Endotélio Vascular , Alanina , Aminoácidos , Ligantes , Simulação de Acoplamento Molecular , Neuropilina-1/química , Neuropilina-1/metabolismo , Peptídeos/química , Fator A de Crescimento do Endotélio Vascular/metabolismo
2.
Cancer Cell Int ; 22(1): 377, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36457009

RESUMO

BACKGROUND: Medulloblastoma (MB) is the most common pediatric malignant brain tumor. Despite current therapies, the morbidity and recurrent risk remains significant. Neuropilin-1 receptor (NRP1) has been implicated in the tumor progression of MB. Our recent study showed that NRP1 inhibition stimulated MB stem cells differentiation. Consequently, we hypothesized that targeting NRP1 in medulloblastoma could improve current treatments. METHODS: NRP1 inhibition with a novel peptidomimetic agent, MR438, was evaluated with radiotherapy (RT) in MB models (DAOY, D283-Med and D341-Med) in vitro on cancer stem-like cells as well as in vivo on heterotopic and orthotopic xenografts. RESULTS: We show that NRP1 inhibition by MR438 radiosensitizes MB stem-like cells in vitro. In heterotopic DAOY models, MR438 improves RT efficacy as measured by tumor growth and mouse survival. In addition, clonogenic assays after tumor dissociation showed a significant reduction in cancer stem cells with the combination treatment. In the same way, a benefit of the combined therapy was observed in the orthotopic model only for a low cumulative irradiation dose of 10 Gy but not for 20 Gy. CONCLUSIONS: Finally, our results demonstrated that targeting NRP1 with MR438 could be a potential new strategy and could limit MB progression by decreasing the stem cell number while reducing the radiation dose.

3.
Bioorg Med Chem ; 45: 116313, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34325324

RESUMO

The [3.3.0]furofuranone structure is found in numerous families of biologically active natural products. We took advantage of the stereodiversity afforded by carbohydrate derivatives to prepare several compounds structurally similar to goniofufurone and crassalactones which are natural cytotoxic agents. We designed and synthesized several stereoisomers of these natural compounds via lactonization of C-glycosyl compounds bearing an hydroxyl on position 4 and a methyl ester on the pseudo-anomeric positionThe reactivity of this bicyclic moiety was explored through etherification of hydroxyls in position 5 and 7 and various substituants (halogen, phenyl, benzyl, cynanmoyl) were introduced. The anti-proliferative properties of these mimics were then evaluated on various cancer cell lines and two compounds 24 and 35 demonstrated IC50 value of 1.34 µM (U251) and 7.60 µM (U87) respectively.


Assuntos
Antineoplásicos/farmacologia , Furanos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Furanos/síntese química , Furanos/química , Humanos , Masculino , Estrutura Molecular , Relação Estrutura-Atividade , Células Tumorais Cultivadas
4.
Bioorg Med Chem ; 24(21): 5315-5325, 2016 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-27622745

RESUMO

Neuropilin-1 (NRP-1), a transmembrane glycoprotein acting as a co-receptor of VEGF-A, is expressed by cancer and angiogenic endothelial cells and is involved in the angiogenesis process. Taking advantage of functionalities and stereodiversities of sugar derivatives, the design and the synthesis of carbohydrate based peptidomimetics are here described. One of these compounds (56) demonstrated inhibition of VEGF-A165 binding to NRP-1 (IC50=39µM) and specificity for NRP-1 over VEGF-R2. Biological evaluations were performed on human umbilical vein endothelial cells (HUVECs) through activation of downstream proteins (AKT and ERK phosphorylation), viability/proliferation assays and in vitro measurements of anti-angiogenic abilities.


Assuntos
Carboidratos/farmacologia , Simulação de Acoplamento Molecular , Neuropilina-1/antagonistas & inibidores , Peptidomiméticos/síntese química , Peptidomiméticos/farmacologia , Carboidratos/síntese química , Carboidratos/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Estrutura Molecular , Peptidomiméticos/química , Relação Estrutura-Atividade
5.
Int J Mol Sci ; 16(10): 24059-80, 2015 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-26473840

RESUMO

Photodynamic therapy (PDT) is a cancer treatment modality that requires three components, namely light, dioxygen and a photosensitizing agent. After light excitation, the photosensitizer (PS) in its excited state transfers its energy to oxygen, which leads to photooxidation reactions. In order to improve the selectivity of the treatment, research has focused on the design of PS covalently attached to a tumor-targeting moiety. In this paper, we describe the synthesis and the physico-chemical and photophysical properties of six new peptide-conjugated photosensitizers designed for targeting the neuropilin-1 (NRP-1) receptor. We chose a TPC (5-(4-carboxyphenyl)-10,15, 20-triphenyl chlorine as photosensitizer, coupled via three different spacers (aminohexanoic acid, 1-amino-3,6-dioxaoctanoic acid, and 1-amino-9-aza-3,6,12,15-tetraoxa-10-on-heptadecanoic acid) to two different peptides (DKPPR and TKPRR). The affinity towards the NRP-1 receptor of the conjugated chlorins was evaluated along with in vitro and in vivo stability levels. The tissue concentration of the TPC-conjugates in animal model shows good distribution, especially for the DKPPR conjugates. The novel peptide-PS conjugates proposed in this study were proven to have potential to be further developed as future NRP-1 targeting photodynamic therapy agent.


Assuntos
Neoplasias/terapia , Neuropilina-1/metabolismo , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Porfirinas/farmacologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Modelos Animais de Doenças , Feminino , Camundongos , Camundongos Nus , Oxigênio/química , Peptídeos/química , Peptídeos/metabolismo , Fármacos Fotossensibilizantes/síntese química , Fármacos Fotossensibilizantes/química , Polietilenoglicóis/química , Porfirinas/química , Porfirinas/farmacocinética , Ligação Proteica
6.
Immunotargets Ther ; 13: 319-333, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38948503

RESUMO

Purpose: Medulloblastoma (MB) is the most prevalent paediatric brain tumour. Despite improvements in patient survival with current treatment strategies, the quality of life of these patients remains poor owing to the sequelae and relapse risk. An alternative, or, in addition to the current standard treatment, could be considered immunotherapy, such as Natural Killer cells (NK). NK cells are cytotoxic innate lymphoid cells that play a major role in cancer immunosurveillance. To date, the mechanism of cytotoxicity of NK cells, especially regarding the steps of adhesion, conjugation, cytotoxic granule polarisation in the cell contact area, perforin and granzyme release in two and three dimensions, and therapeutic efficacy in vivo have not been precisely described. Materials and Methods: Each step of NK cytotoxicity against the three MB cell lines was explored using confocal microscopy for conjugation, Elispot for degranulation, flow cytometry, and luminescence assays for target cell necrosis and lysis and mediators released by cytokine array, and then confirmed in a 3D spheroid model. Medulloblastoma-xenografted mice were treated with NK cells. Their persistence was evaluated by flow cytometry, and their efficacy in tumour growth and survival was determined. In addition, their effects on the tumour transcriptome were evaluated. Results: NK cells showed variable affinities for conjugation with MB target cells depending on their subgroup and cytokine activation. Chemokines secreted during NK and MB cell co-culture are mainly associated with angiogenesis and immune cell recruitment. NK cell cytotoxicity induces MB cell death in both 2D and 3D co-culture models. NK cells initiated an inflammatory response in a human MB murine model by modulating the MB cell transcriptome. Conclusion: Our study confirmed that NK cells possess both in vitro and in vivo cytotoxic activity against MB cells and are of interest for the development of immunotherapy.

7.
Microvasc Res ; 83(2): 131-7, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21820450

RESUMO

Overexpression of EGFR plays a key-role in head and neck squamous cell carcinoma (HNSCC) and justifies the extensive use of cetuximab, a monoclonal anti-EGFR antibody, as well as EGFR-tyrosine kinase inhibitors (EGFR-TKI), which have been reported to inhibit tumor cell growth and the secretion of pro-angiogenic factors by tumor cells, such as VEGF and IL-8. Moreover, vessel normalization in tumors, suggesting a more complex mediation of endothelial cell growth control has also been observed in vivo. The present study was designed to investigate the angiogenic consequences of exposure of HNSCC tumor cell lines to cetuximab and intercellular signaling between tumor and endothelial cells by secretion of pro- and anti-angiogenic mediators in the conditioned media (CM). The results achieved showed that cetuximab decreased the secretion of VEGF by HNSCC cells and that exposure of human umbilical vein endothelial cells (HUVEC) to CM from HNSCC cells exposed to cetuximab induced an increase in endothelial cell network formation. Angiogenesis proteome profiling showed that cetuximab induced a complex alteration of the secretion of pro- and anti-angiogenic factors by HNSCC cells without enabling to identify a unique molecular marker. Expression of endothelial membrane receptors (VEGFR-2, EGFR, PECAM-1 and Notch-4) was investigated and only EGFR expression was found influenced when HUVEC were exposed to CM from cetuximab-exposed HNSCC cells. These results showed that the decrease in the secretion of pro-angiogenic agents like VEGF by HNSCC cells exposed to cetuximab could not be sufficient to justify its anti-angiogenic activity in vitro.


Assuntos
Inibidores da Angiogênese/farmacologia , Proteínas Angiogênicas/metabolismo , Anticorpos Monoclonais/farmacologia , Carcinoma de Células Escamosas/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Neovascularização Fisiológica/efeitos dos fármacos , Comunicação Parácrina/efeitos dos fármacos , Neoplasias da Língua/metabolismo , Anticorpos Monoclonais Humanizados , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cetuximab , Meios de Cultivo Condicionados/metabolismo , Relação Dose-Resposta a Droga , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/metabolismo , Humanos , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Receptor Notch4 , Receptores Notch/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
8.
Pharmaceuticals (Basel) ; 15(12)2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36558941

RESUMO

Considering the individual characteristics of positron emission tomography (PET) and optical imaging (OI) in terms of sensitivity, spatial resolution, and tissue penetration, the development of dual imaging agents for bimodal PET/OI imaging is a growing field. A current major breakthrough in this field is the design of monomolecular agent displaying both a radioisotope for PET and a fluorescent dye for OI. We took advantage of the multifunctionalities allowed by a clickable C-glycosyl scaffold to gather the different elements. We describe, for the first time, the synthesis of a cyanine-based dual PET/OI imaging probe based on a versatile synthetic strategy and its direct radiofluorination via [18F]F-C bond formation. The non-radioactive dual imaging probe coupled with two c(RGDfK) peptides was evaluated in vitro and in vivo in fluorescence imaging. The binding on αvß3 integrin (IC50 = 16 nM) demonstrated the efficiency of the dimeric structure and PEG linkers in maintaining the affinity. In vivo fluorescence imaging of U-87 MG engrafted nude mice showed a high tumor uptake (40- and 100-fold increase for orthotopic and ectopic brain tumors, respectively, compared to healthy brain). In vitro and in vivo evaluations and resection of the ectopic tumor demonstrated the potential of the conjugate in glioblastoma cancer diagnosis and image-guided surgery.

9.
Front Oncol ; 11: 665634, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34277411

RESUMO

Neuropilins are transmembrane glycoproteins that play important roles in cardiovascular and neuronal development, as well as in immunological system regulations. NRP1 functions as a co-receptor, binding numerous ligands, such as SEMA 3 or VEGF and, by doing so, reinforcing their signaling pathways and can also interface with the cytoplasmic protein synectin. NRP1 is expressed in many cancers, such as brain cancers, and is associated with poor prognosis. The challenge today for patients with pediatric brain tumors is to improve their survival rate while minimizing the toxicity of current treatments. The aim of this review is to highlight the involvement of NRP1 in pediatric brain cancers, focusing essentially on the roles of NRP1 in cancer stem cells and in the regulation of the immune system. For this purpose, recent literature and tumor databases were analyzed to show correlations between NRP1 and CD15 (a stem cancer cells marker), and between NRP1 and PDL1, for various pediatric brain tumors, such as high- and low-grade gliomas, medulloblastomas, and ependymomas. Finally, this review suggests a relevant role for NRP1 in pediatric brain tumors progression and identifies it as a potential diagnostic or therapeutic target to improve survival and life quality of these young patients.

10.
Crit Rev Oncol Hematol ; 160: 103261, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33607229

RESUMO

Monoclonal antibodies targeting tumors are one of the most important discoveries in the field of cancer. Although several effective antibodies have been developed, a relapse may occur. One of their mechanisms of action is Antibody Dependent Cell Cytotoxicity (ADCC), by engaging the Fc γ receptor CD16 expressing Natural Killer cells, innate lymphoid cells involved in cancer immunosurveillance and able to kill tumor cells. A lack of NK cells observed in many cancers may therefore be a cause of the low efficacy of antibodies observed in some clinical situations. Here we review clear evidences of the essential partnership between NK cells and antibodies showed in vitro, in vivo, and in clinical trials in different indications, describe the hurdles and ways to enhance ADCC and the evolution of monoclonal antibody therapy. NK cell adoptive immunotherapy combined with monoclonal antibodies may overcome the resistance to the treatment and enhance their efficacy.


Assuntos
Anticorpos Monoclonais , Imunidade Inata , Anticorpos Monoclonais/uso terapêutico , Citotoxicidade Celular Dependente de Anticorpos , Linhagem Celular Tumoral , Humanos , Células Matadoras Naturais
11.
ACS Appl Bio Mater ; 4(2): 1330-1339, 2021 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-35014484

RESUMO

Photodynamic therapy (PDT) is a promising technique to treat different kinds of disease especially cancer. PDT requires three elements: molecular oxygen, a photoactivatable molecule called the photosensitizer (PS), and appropriate light. Under illumination, the PSs generate, in the presence of oxygen, the formation of reactive oxygen species including singlet oxygen, toxic, which then destroys the surrounding tissues. Even if PDT is used with success to treat actinic keratosis or prostate cancer for example, PDT suffers from two major drawbacks: the lack of selectivity of most of the PSs currently used clinically as well as the need for oxygen to be effective. To remedy the lack of selectivity, targeting the tumor neovessels is a promising approach to destroy the vascularization and cause asphyxia of the tumor. KDKPPR peptide affinity for the neuropilin-1 (NRP-1) receptor overexpressed on endothelial cells has already been proven. To compensate for the lack of oxygen, we focused on photoactivatable alkoxyamines (Alks), molecules capable of generating toxic radicals by light activation. In this article, we describe the synthesis of a multifunctional platform combining three units: a PS for an oxygen-dependent PDT, a peptide to target tumor neovessels, and an Alk for an oxygen-independent activity. The synthesis of the compound was successfully carried out, and the study of its photophysical properties showed that the PS retained its capacity to form singlet oxygen and the affinity tests confirmed the affinity of the compound for NRP-1. Thanks to the electron paramagnetic resonance spectroscopy, a technique of choice for radical investigation, the radicals generated by the illumination of the Alk could be detected. The proof of concept was thus successfully established.


Assuntos
Sistemas de Liberação de Medicamentos , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/administração & dosagem , Fármacos Fotossensibilizantes/uso terapêutico , Espectroscopia de Ressonância de Spin Eletrônica , Modelos Moleculares , Estrutura Molecular , Oxigênio , Peptídeos , Fotoquímica
12.
RSC Adv ; 11(13): 7672-7681, 2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-35423261

RESUMO

The design of bifunctional chelating agents (BFCA) allowing straightforward radiometal labelling of biomolecules is a current challenge. We report herein the development of a bifunctional chelating agent based on a DOTA chelator linked to a C-glycosyl compound, taking advantage of the robustness and hydrophilicity of this type of carbohydrate derivative. This new BFCA was coupled with success by CuAAC with c(RGDfK) for αvß3 integrin targeting. As attested by in vitro evaluation, the conjugate DOTA-C-glyco-c(RGDfC) demonstrated high affinity for αvß3 integrins (IC50 of 42 nM). [68Ga]Ga-DOTA-C-glyco-c(RGDfK) was radiosynthesized straightforwardly and showed high hydrophilic property (log D 7.4 = -3.71) and in vitro stability (>120 min). Preliminary in vivo PET study of U87MG engrafted mice gave evidence of an interesting tumor-to-non-target area ratio. All these data indicate that [68Ga]Ga-DOTA-C-glyco-c(RGDfK) allows monitoring of αvß3 expression and could thus be used for cancer diagnosis. The DOTA-C-glycoside BFCA reported here could also be used with various ligands and chelating other (radio)metals opening a broad scope of applications in imaging modalities and therapy.

13.
Adv Drug Deliv Rev ; 138: 344-357, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30414495

RESUMO

Glioblastoma multiforme (GBM) is the most aggressive malignant brain tumor. Despite new knowledges on the genetic characteristics, conventional therapy for GBM, tumor resection followed by radiotherapy and chemotherapy using temozolomide is limited in efficacy due to high rate of recurrence. GBM is indeed one of the most complex and difficult cancer to treat mainly due to its highly invasive properties and the standard treatments are thus rarely curative. Major challenges in the treatment of GBM are the limitation of irreversible brain damage, the infiltrative part of the tumor which is the ultimate cause of recurrence, the difficulty of identifying tumor margins and disseminated tumor cells, and the transport across the blood-brain barrier in order to obtain a sufficient therapeutic effect for pharmalogical agents. Considering these limitations, this review explores the in vivo potential of metal-based nanoparticles for hyperthermia, radiotherapy and photodynamic therapy. This article describes and clearly outlines the recent in vivo advances using innovative therapeutic metallic nanoparticles such as iron oxide, silver, gadolinium and gold nanoparticles.


Assuntos
Neoplasias Encefálicas/terapia , Glioblastoma/terapia , Nanopartículas Metálicas/administração & dosagem , Estimulação Física , Animais , Barreira Hematoencefálica/metabolismo , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/radioterapia , Humanos , Hipertermia Induzida , Fotoquimioterapia
14.
Oncotarget ; 9(20): 15312-15325, 2018 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-29632646

RESUMO

Medulloblastoma (MB) is the most common malignant pediatric brain tumor. Despite the progress of new treatments, the risk of recurrence, morbidity, and death remains important. The neuropilin-1 (NRP-1) receptor has recently been implicated in tumor progression of MB, which seems to play an important role in the phenotype of cancer stem cells. Targeting this receptor appears as an interesting strategy to promote MB stem cells differentiation. Cancer stem-like cells of 3 MB cell lines (DAOY, D283-Med and D341-Med), classified in the more pejorative molecular subgroups, were obtained by in vitro enrichment. These models were characterized by an increase of NRP-1 and cancer stem cell markers (CD15, CD133 and Sox2), meanwhile a decrease of the differentiated cell marker Neurofilament-M (NF-M) was observed. Our previous work investigated potential innovative peptidomimetics that specifically target NRP-1 and showed that MR438 had a good affinity for NRP-1. This small molecule decreased the self-renewal capacity of MB stem cells for the 3 cell lines and reduced the invasive ability of DAOY and D283 stem cells while NRP-1 expression and cancer stem cell markers decreased at the same time. Possible molecular mechanisms were explored and showed that the activation of PI3K/AKT and MAPK pathways significantly decreased for DAOY cells after treatment. Finally, our results highlighted that targeting NRP-1 with MR438 could be a potential new strategy to differentiate MB stem cells and could limit medulloblastoma progression.

15.
Clin Hemorheol Microcirc ; 37(1-2): 89-98, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17641399

RESUMO

Although autogenous vessels are useful in surgery, often patients cannot furnish suitable vessels. If there are not available, two possible alternatives for vessel replacements are to use vascular synthetic prostheses such as Dacron((R)) and polytetrafluoroethylene (PTFE) or cryopreserved allografts. However, their success has been limited to replace small-diameter (<6 mm) arterial vessel because of their high thrombogenicity and compliance mismatch. On account of a clear clinical need for a functional arterial substitute, tissue engineering techniques have been developed. This review encompasses the use of mature endothelial, endothelial progenitor and bone marrow cells combined with natural or synthetic scaffolds whose surface has been modified with multiple origin matrices.


Assuntos
Prótese Vascular , Engenharia Tecidual/métodos , Células da Medula Óssea/citologia , Técnicas de Cultura de Células , Células Endoteliais/citologia , Humanos , Polímeros/uso terapêutico , Células-Tronco/citologia , Transplante Autólogo
16.
Int J Nanomedicine ; 12: 7075-7088, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29026302

RESUMO

Despite combined treatments, glioblastoma outcome remains poor with frequent local recurrences, indicating that a more efficient and local therapy is needed. In this way, vascular-targeted photodynamic therapy (VTP) could help tumor eradication by destroying its neovessels. In this study, we designed a polysiloxane-based nanoparticle (NP) combining a magnetic resonance imaging (MRI) contrast agent, a photosensitizer (PS) and a new ligand peptide motif (KDKPPR) targeting neuropilin-1 (NRP-1), a receptor overexpressed by angiogenic endothelial cells of the tumor vasculature. This structure achieves the detection of the tumor tissue and its proliferating part by MRI analysis, followed by its treatment by VTP. The photophysical properties of the PS and the peptide affinity for NRP-1 recombinant protein were preserved after the functionalization of NPs. Cellular uptake of NPs by human umbilical vein endothelial cells (HUVEC) was increased twice compared to NPs without the KDKPPR peptide moiety or conjugated with a scramble peptide. NPs induced no cytotoxicity without light exposure but conferred a photocytotoxic effect to cells after photodynamic therapy (PDT). The in vivo selectivity, evaluated using a skinfold chamber model in mice, confirms that the functionalized NPs with KDKPPR peptide moiety were localized in the tumor vessel wall.


Assuntos
Glioblastoma/irrigação sanguínea , Glioblastoma/tratamento farmacológico , Nanopartículas/química , Tamanho da Partícula , Fotoquimioterapia , Nanomedicina Teranóstica , Animais , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Meios de Contraste , Glioblastoma/patologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Imageamento por Ressonância Magnética , Camundongos , Neuropilina-1/química , Peptídeos/síntese química , Peptídeos/química , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico
17.
J Biomol Struct Dyn ; 35(1): 26-45, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26766582

RESUMO

Vascular endothelial growth factor (VEGF) and its co-receptor neuropilin-1 (NRP-1) are important targets of many pro-angiogenic factors. In this study, nine peptides were synthesized and evaluated for their molecular interaction with NRP-1 and compared to our previous peptide ATWLPPR. Docking study showed that the investigated peptides shared the same binding region as shown by tuftsin known to bind selectively to NRP-1. Four pentapeptides (DKPPR, DKPRR, TKPPR and TKPRR) and a hexapeptide CDKPRR demonstrated good inhibitory activity against NRP-1. In contrast, peptides having arginine residue at sites other than the C-terminus exhibited low activity towards NRP-1 and this is confirmed by their inability to displace the VEGF165 binding to NRP-1. Docking study also revealed that replacement of carboxyl to amide group at the C-terminal arginine of the peptide did not affect significantly the binding interaction to NRP-1. However, the molecular affinity study showed that these peptides have marked reduction in the activity against NRP-1. Pentapeptides having C-terminal arginine showed strong interaction and good inhibitory activity with NRP thus may be a good template for anti-angiogenic targeting agent.


Assuntos
Inibidores da Angiogênese/química , Antineoplásicos/química , Desenho de Fármacos , Modelos Moleculares , Neuropilina-1/química , Peptídeos/química , Sequência de Aminoácidos , Inibidores da Angiogênese/farmacologia , Antineoplásicos/farmacologia , Sítios de Ligação , Humanos , Ligantes , Conformação Molecular , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Neuropilina-1/antagonistas & inibidores , Peptídeos/farmacologia , Ligação Proteica , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Fator A de Crescimento do Endotélio Vascular/química
18.
Cell Biochem Biophys ; 44(2): 223-31, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16456224

RESUMO

Recently, the use of polyelectrolyte films has been suggested as a new versatile technique of surface modification aimed at tissue engineering. In the present study, we evaluated the expression of intercellular adhesion molecule (ICAM)-1 of endothelial cells (ECs) seeded on two types of polyelectrolyte multilayer films either terminated by poly(D-lysine) (PDL) or poly(allylamine hydrochloride) (PAH). This work showed that chemical stimulations with tumor necrosis factor (TNF)-alpha induced the ICAM-1 expression of ECs differently depending largely on the film architecture employed. Compared with PAH-ending films, the PDL-ending ones upregulated the ICAM-1 expression of the ECs after a prolonged exposition to TNF-alpha, rendering this film type less favorable in tissue engineering. Cytochalasin D (an F-actin disrupting agent) showed the involvement of the cytoskeleton in the upregulation of ICAM-1 for cells deposited on films terminated by PDL. The PAH-ending films did not perturb the ICAM-1 expression of ECs and might thus enhance the seeding of ECs in vascular engineering.


Assuntos
Endotélio Vascular/metabolismo , Molécula 1 de Adesão Intercelular/biossíntese , Poliaminas , Células Cultivadas , Citocalasina D/farmacologia , Endotélio Vascular/citologia , Humanos , Polieletrólitos , Estresse Mecânico , Propriedades de Superfície , Engenharia Tecidual , Fator de Necrose Tumoral alfa/farmacologia
19.
Biomaterials ; 26(22): 4568-75, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15722126

RESUMO

The seeding of endothelial cells (ECs) on biomaterial surfaces became a major challenge, allowing to improve the non-thrombogenic properties of these surfaces. Recently, the use of polyelectrolyte films has been suggested as a new versatile technique of surface modification aimed at tissue engineering. In this study, we evaluate the adhesion properties of ECs on two types of polyelectrolyte films ending either by poly(D-lysine) (PDL), or poly(allylamine hydrochloride) (PAH), and compared them to data obtained on PDL or PAH monolayers, glass and fibronectin (Fn)-coated glass. ECs seeded on polyelectrolyte films showed a good morphology, allowing ECs to resist physiological shear stress better compared to ECs seeded on glass or Fn. The expression of beta1 integrins was slightly lower on polyelectrolyte films than on control surfaces. However, the phosphorylation of focal adhesion kinase, involved in the transduction of adhesion signal, was not modified on PAH ending films compared to control surfaces; whereas it became lower on PDL ending films. Finally, PAH ending films improve strongly ECs adhesion without disturbing the adhesion mechanism, necessary for the development of a new endothelium. These types of films or similar build-ups could thus be used in the future as a way to modify surfaces for vascular tissue engineering.


Assuntos
Eletrólitos , Endotélio Vascular/citologia , Actinas/metabolismo , Adesão Celular , Células Cultivadas , Endotélio Vascular/enzimologia , Endotélio Vascular/metabolismo , Quinase 1 de Adesão Focal , Proteína-Tirosina Quinases de Adesão Focal , Humanos , Integrinas/metabolismo , Microscopia de Força Atômica , Proteínas Tirosina Quinases/metabolismo
20.
Life Sci ; 137: 74-80, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26239438

RESUMO

AIMS: Glioma initiating cells (GICs) represent a subpopulation of tumor cells endowed with self-renewal and multilineage differentiation capacity but also with innate resistance to cytotoxic agents, a feature likely to pose major clinical challenges towards the complete eradication of minimal residual disease in glioma patients. MATERIALS AND METHODS: In this work, GICs were obtained from two patient-derived high-grade gliomas xenograft model, expressing differently EGFR. GICs were exposed to anti-EGFR monoclonal antibody cetuximab during 48h in 1% or 21% oxygen tension. Cell viability and self-renewal capacity were then evaluated as well as their angiogenic properties. KEY FINDINGS: GICs were sensitive to cetuximab only in normoxic condition whatever the EGFR status. Nevertheless, under hypoxia cetuximab was able to decrease the self-renewal capacity as well as the expression of CD133 while expression of GFAP increased. Moreover, cetuximab decreased the effect of GICs on endothelial cell migration under hypoxia. SIGNIFICANCE: Consequently, anti-EGFR therapy can be envisaged to target specifically GICs in order to limit the tumor recurrence.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Hipóxia Celular , Cetuximab/farmacologia , Receptores ErbB/antagonistas & inibidores , Glioma/tratamento farmacológico , Glioma/patologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Moduladores da Angiogênese/farmacologia , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/farmacologia , Neoplasias Encefálicas/metabolismo , Movimento Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Receptores ErbB/imunologia , Expressão Gênica/efeitos dos fármacos , Proteína Glial Fibrilar Ácida/metabolismo , Glioma/metabolismo , Humanos , Células Tumorais Cultivadas
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