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1.
J Exp Clin Cancer Res ; 43(1): 137, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38711119

RESUMO

BACKGROUND: The C-terminal-binding protein 1/brefeldin A ADP-ribosylation substrate (CtBP1/BARS) acts both as an oncogenic transcriptional co-repressor and as a fission inducing protein required for membrane trafficking and Golgi complex partitioning during mitosis, hence for mitotic entry. CtBP1/BARS overexpression, in multiple cancers, has pro-tumorigenic functions regulating gene networks associated with "cancer hallmarks" and malignant behavior including: increased cell survival, proliferation, migration/invasion, epithelial-mesenchymal transition (EMT). Structurally, CtBP1/BARS belongs to the hydroxyacid-dehydrogenase family and possesses a NAD(H)-binding Rossmann fold, which, depending on ligands bound, controls the oligomerization of CtBP1/BARS and, in turn, its cellular functions. Here, we proposed to target the CtBP1/BARS Rossmann fold with small molecules as selective inhibitors of mitotic entry and pro-tumoral transcriptional activities. METHODS: Structured-based screening of drug databases at different development stages was applied to discover novel ligands targeting the Rossmann fold. Among these identified ligands, N-(3,4-dichlorophenyl)-4-{[(4-nitrophenyl)carbamoyl]amino}benzenesulfonamide, called Comp.11, was selected for further analysis. Fluorescence spectroscopy, isothermal calorimetry, computational modelling and site-directed mutagenesis were employed to define the binding of Comp.11 to the Rossmann fold. Effects of Comp.11 on the oligomerization state, protein partners binding and pro-tumoral activities were evaluated by size-exclusion chromatography, pull-down, membrane transport and mitotic entry assays, Flow cytometry, quantitative real-time PCR, motility/invasion, and colony assays in A375MM and B16F10 melanoma cell lines. Effects of Comp.11 on tumor growth in vivo were analyzed in mouse tumor model. RESULTS: We identify Comp.11 as a new, potent and selective inhibitor of CtBP1/BARS (but not CtBP2). Comp.11 directly binds to the CtBP1/BARS Rossmann fold affecting the oligomerization state of the protein (unlike other known CtBPs inhibitors), which, in turn, hinders interactions with relevant partners, resulting in the inhibition of both CtBP1/BARS cellular functions: i) membrane fission, with block of mitotic entry and cellular secretion; and ii) transcriptional pro-tumoral effects with significantly hampered proliferation, EMT, migration/invasion, and colony-forming capabilities. The combination of these effects impairs melanoma tumor growth in mouse models.  CONCLUSIONS: This study identifies a potent and selective inhibitor of CtBP1/BARS active in cellular and melanoma animal models revealing new opportunities to study the role of CtBP1/BARS in tumor biology and to develop novel melanoma treatments.


Assuntos
Oxirredutases do Álcool , Proteínas de Ligação a DNA , Melanoma , Humanos , Oxirredutases do Álcool/antagonistas & inibidores , Oxirredutases do Álcool/metabolismo , Oxirredutases do Álcool/genética , Animais , Camundongos , Melanoma/tratamento farmacológico , Melanoma/patologia , Melanoma/metabolismo , Melanoma/genética , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/antagonistas & inibidores , Proteínas de Ligação a DNA/genética , Proliferação de Células/efeitos dos fármacos , Antineoplásicos/farmacologia , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
2.
Animals (Basel) ; 13(12)2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-37370445

RESUMO

The detection of subtle changes in the pituitary dimensions has relevant clinical implications. In cats, a few studies have established the cut-off values of the pituitary gland's dimensions using small and inhomogeneous samples. The aims of this study were: to determine by computed tomography (CT) the pituitary linear dimensions and the pituitary-to-brain (P:B) ratio in a sample of domestic short-haired (DSH) cats; to assess the effects of sex, age, and weight on pituitary dimensions; and to evaluate the inter- and intra-observer agreement for such measurements. All skull CTs of DSH cats performed over four years using a multidetector CT and a standardized protocol were retrospectively reviewed. The exclusion criteria were: clinical, laboratory, or CT alterations of the pituitary gland, brain diseases, fractures of the neurocranium, and diabetes. The pituitary dimensions and brain area were assessed by two different observers using multiplanar reconstructions and automated segmentation tools. Fifty-one cats were included in the final sample. The intraclass correlation coefficients for intra- and inter-observer reliability were good/excellent, and moderate/good, respectively. No differences between sexes were detected, and negligible correlations were found between age and weight. According to this study, a pituitary gland with a height > 4 mm or a P:B ratio > 0.49 mm should be considered enlarged.

3.
Cancers (Basel) ; 13(23)2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34885130

RESUMO

BACKGROUND: We have conducted a systematic review focusing on the advancements in preclinical molecular imaging to study the delivery and therapeutic efficacy of miRNAs in mouse models of breast cancer. METHODS: A systematic review of English articles published in peer-reviewed journals using PubMed, EMBASE, BIOSIS™ and Scopus was performed. Search terms included breast cancer, mouse, mice, microRNA(s) and miRNA(s). RESULTS: From a total of 2073 records, our final data extraction was from 114 manuscripts. The most frequently used murine genetic background was Balb/C (46.7%). The most frequently used model was the IV metastatic model (46.8%), which was obtained via intravenous injection (68.9%) in the tail vein. Bioluminescence was the most used frequently used tool (64%), and was used as a surrogate for tumor growth for efficacy treatment or for the evaluation of tumorigenicity in miRNA-transfected cells (29.9%); for tracking, evaluation of engraftment and for response to therapy in metastatic models (50.6%). CONCLUSIONS: This review provides a systematic and focused analysis of all the information available and related to the imaging protocols with which to test miRNA therapy in an in vivo mice model of breast cancer, and has the purpose of providing an important tool to suggest the best preclinical imaging protocol based on available evidence.

4.
Vet Anaesth Analg ; 48(5): 759-766, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34391668

RESUMO

OBJECTIVE: To develop a comprehensive formula for calculating the volume of local anaesthetic solution used for retrobulbar anaesthesia in dogs with different skull morphologies. STUDY DESIGN: Retrospective cohort imaging study. ANIMALS: Skull computed tomography (CT) images of 188 dogs of different breeds collected between January 2009 and December 2017. METHODS: Anatomical integrity of the orbit and adjacent structures, presenting complaint, clinical signs and CT findings were verified to exclude ocular abnormalities. The volume of the retrobulbar cone of 376 eyes was calculated using CT scans of the dogs' skulls. Additional data recorded included morphology of the skull, body weight, sex and size of the dogs, all of which were matched for possible association to the retrobulbar cone volume through univariable and multivariable linear regression models. Results of linear regression models were expressed as estimated beta coefficients with the corresponding 95% confidence intervals (95% CIs). RESULTS: Using univariate analysis, the retrobulbar cone volume was positively associated with weight and male sex. In addition, brachycephalic and dolichocephalic dogs showed a larger retrobulbar cone volume than mesocephalic dogs, while sex was no longer significantly associated with the retrobulbar cone volume. In multivariate analysis, when considering all variables in the model, weight emerged as the strongest predictor (beta coefficient: 0.062 mL kg-1, 95% CI: 0.056-0.067 mL kg-1, p < 0.001). CONCLUSIONS: and clinical relevance In the veterinary literature, there is no agreement on the precise volume of local anaesthetic solution that should be used to achieve intraconal retrobulbar anaesthesia in dogs. Here we suggest a formula to calculate the retrobulbar cone volume and, accordingly, the injection volume of local anaesthetic solution for effective retrobulbar anaesthesia.


Assuntos
Olho , Órbita , Anestesia Local/veterinária , Animais , Cães , Masculino , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/veterinária
5.
Cell Commun Signal ; 19(1): 64, 2021 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-34088320

RESUMO

BACKGROUND: Invadopodia are actin-based cell-membrane protrusions associated with the extracellular matrix degradation accompanying cancer invasion. The elucidation of the molecular mechanisms leading to invadopodia formation and activity is central for the prevention of tumor spreading and growth. Protein tyrosine kinases such as Src are known to regulate invadopodia assembly, little is however known on the role of protein tyrosine phosphatases in this process. Among these enzymes, we have selected the tyrosine phosphatase Shp1 to investigate its potential role in invadopodia assembly, due to its involvement in cancer development. METHODS: Co-immunoprecipitation and immunofluorescence studies were employed to identify novel substrate/s of Shp1AQ controlling invadopodia activity. The phosphorylation level of cortactin, the Shp1 substrate identified in this study, was assessed by immunoprecipitation, in vitro phosphatase and western blot assays. Short interference RNA and a catalytically-dead mutant of Shp1 expressed in A375MM melanoma cells were used to evaluate the role of the specific Shp1-mediated dephosphorylation of cortactin. The anti-invasive proprieties of glycerophosphoinositol, that directly binds and regulates Shp1, were investigated by extracellular matrix degradation assays and in vivo mouse model of metastasis. RESULTS: The data show that Shp1 was recruited to invadopodia and promoted the dephosphorylation of cortactin at tyrosine 421, leading to an attenuated capacity of melanoma cancer cells to degrade the extracellular matrix. Controls included the use of short interference RNA and catalytically-dead mutant that prevented the dephosphorylation of cortactin and hence the decrease the extracellular matrix degradation by melanoma cells. In addition, the phosphoinositide metabolite glycerophosphoinositol facilitated the localization of Shp1 at invadopodia hence promoting cortactin dephosphorylation. This impaired invadopodia function and tumor dissemination both in vitro and in an in vivo model of melanomas. CONCLUSION: The main finding here reported is that cortactin is a specific substrate of the tyrosine phosphatase Shp1 and that its phosphorylation/dephosphorylation affects invadopodia formation and, as a consequence, the ability of melanoma cells to invade the extracellular matrix. Shp1 can thus be considered as a regulator of melanoma cell invasiveness and a potential target for antimetastatic drugs. Video abstract.


Assuntos
Cortactina/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo , Pseudópodes/metabolismo , Animais , Linhagem Celular Tumoral , Matriz Extracelular/metabolismo , Humanos , Fosfatos de Inositol/metabolismo , Neoplasias Pulmonares/secundário , Melanoma/metabolismo , Melanoma/patologia , Camundongos Endogâmicos BALB C , Camundongos Nus , Modelos Biológicos , Invasividade Neoplásica , Fosforilação , Ligação Proteica , Especificidade por Substrato
6.
Int J Mol Sci ; 22(1)2020 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-33375029

RESUMO

The transcription factor Forkhead box E1 (FOXE1) is a key player in thyroid development and function and has been identified by genome-wide association studies as a susceptibility gene for papillary thyroid cancer. Several cancer-associated polymorphisms fall into gene regulatory regions and are likely to affect FOXE1 expression levels. However, the possibility that changes in FOXE1 expression modulate thyroid cancer development has not been investigated. Here, we describe the effects of FOXE1 gene dosage reduction on cancer phenotype in vivo. Mice heterozygous for FOXE1 null allele (FOXE1+/-) were crossed with a BRAFV600E-inducible cancer model to develop thyroid cancer in either a FOXE1+/+ or FOXE1+/- genetic background. In FOXE1+/+ mice, cancer histological features are quite similar to that of human high-grade papillary thyroid carcinomas, while cancers developed with reduced FOXE1 gene dosage maintain morphological features resembling less malignant thyroid cancers, showing reduced proliferation index and increased apoptosis as well. Such cancers, however, appear severely undifferentiated, indicating that FOXE1 levels affect thyroid differentiation during neoplastic transformation. These results show that FOXE1 dosage exerts pleiotropic effects on thyroid cancer phenotype by affecting histology and regulating key markers of tumor differentiation and progression, thus suggesting the possibility that FOXE1 could behave as lineage-specific oncogene in follicular cell-derived thyroid cancer.


Assuntos
Fatores de Transcrição Forkhead/genética , Regulação Neoplásica da Expressão Gênica , Câncer Papilífero da Tireoide/genética , Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/genética , Animais , Apoptose/genética , Diferenciação Celular/genética , Proliferação de Células/genética , Transformação Celular Neoplásica/genética , Fatores de Transcrição Forkhead/metabolismo , Pleiotropia Genética , Humanos , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/metabolismo , Câncer Papilífero da Tireoide/metabolismo , Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/metabolismo
7.
Cancers (Basel) ; 12(7)2020 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-32708431

RESUMO

The chemokine receptor CXCR4 is overexpressed and functional in colorectal cancer. To investigate the role of CXCR4 antagonism in potentiating colon cancer standard therapy, the new peptide CXCR4 antagonist Peptide R (Pep R) was employed. Human colon cancer HCT116 xenograft-bearing mice were treated with chemotherapeutic agents (CT) 5-Fluorouracil (5FU) and oxaliplatin (OX) or 5FU and radio chemotherapy (RT-CT) in the presence of Pep R. After two weeks, CT plus Pep R reduced by 4-fold the relative tumor volume (RTV) as compared to 2- and 1.6-fold reductions induced, respectively, by CT and Pep R. In vitro Pep R addition to CT/RT-CT impaired HCT116 cell growth and further reduced HCT116 and HT29 clonal capability. Thus, the hypothesis that Pep R could target the epithelial mesenchyme transition (EMT) process was evaluated. While CT decreased ECAD and increased ZEB-1 and CD90 expression, the addition of Pep R restored the pretreatment expression. In HCT116 and HT29 cells, CT/RT-CT induced a population of CD133+CXCR4+ cells, supposedly a stem-resistant cancer cell population, while Pep R reduced it. Taken together, the results showed that targeting CXCR4 ameliorates the effect of treatment in colon cancer through inhibition of cell growth and reversal of EMT treatment-induced markers, supporting further clinical studies.

8.
Mol Carcinog ; 58(7): 1181-1193, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30834573

RESUMO

Junctional adhesion molecule A (JAM-A) is a transmembrane protein that contributes to different biological process, including the epithelial to mesenchymal transition (EMT). Through an EMT profiler array, we explored the molecular players associated with human thyroid cancer progression and identified JAM-A as one of the genes mostly deregulated. The quantitative real-time polymerase chain reaction and immunohistochemistry analyses showed that downregulation of JAM-A occurred in anaplastic thyroid carcinoma (ATC) compared with normal thyroid (NT) and papillary thyroid carcinoma (PTC) tissues and correlated with extrathyroid infiltration, tumor size, and ATC histotype. In ATC cell lines, JAM-A restoration suppressed malignant hallmarks of transformation including cell proliferation, motility, and transendothelial migration. Accordingly, knockdown of JAM-A enhanced thyroid cancer cell proliferation and motility in PTC cells. Through the proteome profiler human phospho-kinase array, we demonstrated that higher expression of JAM-A was associated with a significant increased level of phosphorylation of p53 and GSK3 α/ß proteins. In conclusion, our findings highlight a novel role of JAM-A in thyroid cancer progression and suggest that JAM-A restoration could have potential clinical relevance in thyroid cancer treatment.


Assuntos
Moléculas de Adesão Celular/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Quinase 3 da Glicogênio Sintase/metabolismo , Receptores de Superfície Celular/metabolismo , Câncer Papilífero da Tireoide/patologia , Carcinoma Anaplásico da Tireoide/patologia , Proteína Supressora de Tumor p53/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Transição Epitelial-Mesenquimal/fisiologia , Humanos , Interferência de RNA , RNA Interferente Pequeno/genética , Neoplasias da Glândula Tireoide/patologia
9.
Gene Ther ; 26(3-4): 121-130, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30700805

RESUMO

Familial hypercholesterolemia (FH) is a genetic hyperlipidemia characterized by elevated concentrations of plasma LDL cholesterol. Statins are not always effective for the treatment of FH patients; unresponsive patients have poor prognosis and rely on LDL apheresis. In the past, we developed safe and effective gene therapy strategies for the expression of anti-atherogenic proteins using PEGylated helper-dependent adenoviral (HD-Ad) vectors. We recently developed a HD-Ad vector for the expression of the soluble form of the extracellular portion of the human LDL receptor (LDLR) fused with a rabbit transferrin dimer (LDLR-TF). We evaluated the efficacy of the LDLR-TF chimeric protein  in CHOLDLA7, a cell line lacking LDLR expression, restoring the ability to uptake LDL. Subsequently, we administered intravenously 1 × 10E13 vp/kg of this vector in LDLR-deficient mice and observed amelioration of lipid profile and reduction of aortic atherosclerosis. Finally, we studied LDL distribution after HD-Ad vector-mediated expression of LDLR-TF in LDLR-deficient mice and found LDL accumulation in liver, and in heart and intestine. These results support the possibility of lowering LDL-C levels and reducing aortic atherosclerosis using a secreted therapeutic transgene; the present strategy potentially can be modified and adapted to non-systemic gene transfer with expression of the secreted chimeric protein in muscle or other tissues. Intramuscular or local administration strategies could improve the safety profile of this strategy and facilitate applicability.


Assuntos
Terapia Genética/métodos , Receptores de LDL/genética , Transferrina/genética , Adenoviridae/genética , Infecções por Adenoviridae/genética , Animais , Aorta/patologia , Aterosclerose/genética , Linhagem Celular , LDL-Colesterol/sangue , Doença da Artéria Coronariana/genética , Doença da Artéria Coronariana/fisiopatologia , Técnicas de Transferência de Genes , Vetores Genéticos/genética , Humanos , Lipídeos/sangue , Camundongos , Receptores de LDL/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/uso terapêutico , Transferrina/metabolismo , Transgenes
10.
Nanomedicine ; 14(2): 483-491, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29175599

RESUMO

Nanoparticles (NPs) are a promising tool for in vivo multimodality imaging and theranostic applications. Hyaluronic acid (HA)-based NPs have numerous active groups that make them ideal as tumor-targeted carriers. The B-lymphoma neoplastic cells express on their surfaces a clone-specific immunoglobulin receptor (Ig-BCR). The peptide A20-36 (pA20-36) selectively binds to the Ig-BCR of A20 lymphoma cells. In this work, we demonstrated the ability of core-shell chitosan-HA-NPs decorated with pA20-36 to specifically target A20 cells and reduce the tumor burden in a murine xenograft model. We monitored tumor growth using high-frequency ultrasonography and demonstrated targeting specificity and kinetics of the NPs via in vivo fluorescent reflectance imaging. This result was also confirmed by ex vivo magnetic resonance imaging and confocal microscopy. In conclusion, we demonstrated the ability of NPs loaded with fluorescent and paramagnetic tracers to act as multimodal imaging contrast agents and hence as a non-toxic, highly specific theranostic system.


Assuntos
Linfoma de Células B/tratamento farmacológico , Imagem Multimodal/métodos , Nanopartículas/administração & dosagem , Fragmentos de Peptídeos/administração & dosagem , Nanomedicina Teranóstica , Animais , Quitosana/química , Humanos , Ácido Hialurônico/química , Linfoma de Células B/diagnóstico por imagem , Linfoma de Células B/patologia , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanopartículas/química , Fragmentos de Peptídeos/química , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Int J Mol Sci ; 18(12)2017 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-29258188

RESUMO

Thyroid cancer, which represents the most common tumors among endocrine malignancies, comprises a wide range of neoplasms with different clinical aggressiveness. One of the most important challenges in research is to identify mouse models that most closely resemble human pathology; other goals include finding a way to detect markers of disease that common to humans and mice and to identify the most appropriate and least invasive therapeutic strategies for specific tumor types. Preclinical thyroid imaging includes a wide range of techniques that allow for morphological and functional characterization of thyroid disease as well as targeting and in most cases, this imaging allows quantitative analysis of the molecular pattern of the thyroid cancer. The aim of this review paper is to provide an overview of all of the imaging techniques used to date both for diagnosis and theranostic purposes in mouse models of thyroid cancer.


Assuntos
Neoplasias da Glândula Tireoide/diagnóstico por imagem , Animais , Modelos Animais de Doenças , Humanos , Camundongos
12.
Theranostics ; 7(14): 3595-3607, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28912898

RESUMO

Bone marrow-derived mesenchymal stem cells (BM-MSCs) are shown to participate in tumor progression by establishing a favorable tumor microenvironment (TME) that promote metastasis through a cytokine networks. However, the mechanism of homing and recruitment of BM-MSCs into tumors and their potential role in malignant tissue progression is poorly understood and controversial. Here we show that BM-MSCs increase aggressiveness of triple-negative breast cancer (TNBC) cell lines evaluated as capability to migrate, invade and acquire stemness markers. Importantly, we demonstrate that the treatment of BM-MSCs with a nuclease-resistant RNA aptamer against platelet-derived growth factor receptor ß (PDGFRß) causes the inhibition of receptor-dependent signaling pathways thus drastically hampering BM-MSC recruitment towards TNBC cell lines and BM-MSCs trans-differentiation into carcinoma-associated fibroblast (CAF)-like cells. Moreover, in vivo molecular imaging analysis demonstrated the aptamer ability to prevent BM-MSCs homing to TNBC xenografts. Collectively, our results indicate the anti-PDGFRß aptamer as a novel therapeutic tool to interfere with BM-MSCs attraction to TNBC providing the rationale to further explore the aptamer in more complex pre-clinical settings.


Assuntos
Aptâmeros de Nucleotídeos/genética , Movimento Celular , Células-Tronco Mesenquimais/metabolismo , Receptor beta de Fator de Crescimento Derivado de Plaquetas/genética , Neoplasias de Mama Triplo Negativas/terapia , Microambiente Tumoral , Animais , Transdiferenciação Celular , Células Cultivadas , Feminino , Fibroblastos/metabolismo , Fibroblastos/patologia , Humanos , Células MCF-7 , Células-Tronco Mesenquimais/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Terapêutica com RNAi/métodos , Receptor beta de Fator de Crescimento Derivado de Plaquetas/metabolismo , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia
13.
Genes Cancer ; 8(5-6): 577-588, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28740576

RESUMO

We have previously shown that miR-146a, a NF-κB-regulated microRNA, is strongly expressed in human specimens and cell lines derived from anaplastic thyroid carcinomas (ATC) where it mediates some of the NF-κB pro-tumorigenic functions. By using a bioinformatic analysis, we identified the chemokine scavenger receptor D6/ ACKR2 as a target of miR146a in human ATC. We found that the expression of D6/ ACKR2 was up-regulated in miR-146a-null ATC cell lines and that the 3' UTR of D6/ ACKR2 mRNA was able to inhibit its expression in parental, but not in miR-146a-null ATC cells. Since human specimens from primary ATC showed a low expression of D6/ ACKR2 compared to normal thyroid tissues, we analyzed the effects of D6/ACKR2 over-expression in ATC cells. Different chemokines added to the conditioned medium of D6/ACKR2 over-expressing ATC cells partially failed to drive in vitro monocyte migration, and tumors derived from the injection of the same cells in nude mice showed a decreased number of infiltrating macrophages. Taken together, these results indicate that ATC cells down-regulate D6/ACKR2 expression through miR-146a activity to sustain leukocyte trafficking inside tumor microenvironment and shed light on a novel mechanism by which NF-κB indirectly inhibits the expression and the function of anti-tumorigenic gene in thyroid cancer.

14.
Sci Rep ; 7(1): 2554, 2017 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-28566721

RESUMO

C-X-C chemokine receptor 4 (CXCR4) is over-expressed in multiple human cancers and correlates with tumor aggressiveness, poor prognosis and increased risk for distant metastases. Imaging agents for CXCR4 are thus highly desirable. We developed a novel CXCR4-targeted near-infrared (NIR) fluorescent probe (Peptide R-NIR750) conjugating the new developed CXCR4 peptidic antagonist Peptide R with the NIR fluorescent dye VivoTag-S750. Specific CXCR4 binding was obtained in cells overexpressing human CXCR4 (B16-hCXCR4 and human melanoma cells PES43), but not in CXCR4 low expressing cells (FB-1). Ex vivo evaluation demonstrated that PepR-NIR750 specifically detects B16-hCXCR4-derived subcutaneous tumors and lung metastases. Fluorescence Molecular Tomography (FMT) in vivo imaging was performed on mice carrying subcutaneous CHO and CHO-CXCR4 tumors. PepR-NIR750 accumulates only in CXCR4-positive expressing subcutaneous tumors. Additionally, an intense NIR fluorescence signal was detected in PES43-derived lung metastases of nude mice injected with PepR-NIR750 versus mice injected with VivoTag-S750. With a therapeutic intent, mice bearing PES43-derived lung metastases were treated with Peptide R. A the dramatic reduction in PES43-derived lung metastases was detected through a decrease of the PepR-NIR750 signal. PepR-NIR750 is a specific probe for non-invasive detection of human high CXCR4-expressing tumors and metastatic lesion and thus a valuable tool for cancer molecular imaging.


Assuntos
Biomarcadores Tumorais/genética , Corantes Fluorescentes/metabolismo , Neoplasias Pulmonares/diagnóstico por imagem , Melanoma Experimental/diagnóstico por imagem , Oligopeptídeos/metabolismo , Neoplasias Cutâneas/diagnóstico por imagem , Animais , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Corantes Fluorescentes/síntese química , Expressão Gênica , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/secundário , Melanoma Experimental/genética , Melanoma Experimental/metabolismo , Melanoma Experimental/patologia , Camundongos , Camundongos Nus , Oligopeptídeos/síntese química , Ligação Proteica , Receptores CXCR4/genética , Receptores CXCR4/metabolismo , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia , Espectrometria de Fluorescência/instrumentação , Espectrometria de Fluorescência/métodos , Espectroscopia de Luz Próxima ao Infravermelho/instrumentação , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Tomografia/instrumentação , Tomografia/métodos
15.
Q J Nucl Med Mol Imaging ; 61(1): 19-32, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27858404

RESUMO

Preclinical molecular imaging is an emerging field. Improving the ability of scientists to study the molecular basis of human pathology in animals is of the utmost importance for future advances in all fields of human medicine. Moreover, the possibility of developing new imaging techniques or of implementing old ones adapted to the clinic is a significant area. Cardiology, neurology, immunology and oncology have all been studied with preclinical molecular imaging. The functional techniques of photoacoustic imaging (PAI), fluorescence molecular tomography (FMT), positron emission tomography (PET), and single photon emission computed tomography (SPECT) in association with each other or with the anatomic reference provided by computed tomography (CT) as well as with anatomic and functional information provided by magnetic resonance (MR) have all been proficiently applied to animal models of human disease. All the above-mentioned imaging techniques have shown their ability to explore the molecular mechanisms involved in animal models of disease. The clinical translatability of most of the techniques motivates the ongoing study of their possible fields of application. The ability to combine two or more techniques allows obtaining as much information as possible on the molecular processes involved in pathologies, reducing the number of animals necessary in each experiment. Merging molecular probes compatible with various imaging technique will further expand the capability to achieve the best results.


Assuntos
Imagem Multimodal/métodos , Animais , Doença , Humanos
16.
Q J Nucl Med Mol Imaging ; 61(1): 76-94, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27858405

RESUMO

Several advances have been made toward understanding the biology of cancer and most of them are due to robust genetic studies that led to the scientific recognition that although many patients have the same type of cancer their tumors may have harbored different molecular alterations. Personalized therapy and the development of advanced techniques of preclinical imaging and new murine models of disease are emerging concepts that are allowing mapping of disease markers in vivo and in some cases also receptor targeted therapy. Aim of this review is to illustrate some emerging models of disease that allow patient tumor implantation in mice for subsequent drug testing and advanced approaches for therapy mediated by preclinical imaging. In particular we discuss targeted therapy mediated by high frequency ultrasound and magnetic resonance, two emerging techniques in molecular preclinical therapy.


Assuntos
Diagnóstico por Imagem/métodos , Neoplasias/diagnóstico por imagem , Neoplasias/terapia , Animais , Sistemas de Liberação de Medicamentos , Humanos , Medicina de Precisão
17.
Front Microbiol ; 7: 1750, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27872616

RESUMO

Bartonella henselae is a gram-negative facultative intracellular bacterium and is the causative agent of cat-scratch disease. Our previous data have established that Bacteroides fragilis colonization is able to prevent B. henselae damages through the polysaccharide A (PSA) in an experimental murine model. In order to determine whether the PSA is essential for the protection against pathogenic effects of B. henselae in immunocompromised hosts, SCID mice were co-infected with B. fragilis wild type or its mutant B. fragilis ΔPSA and the effects of infection on murine tissues have been observed by High-Frequency Ultrasound (HFUS), histopathological examination, and Transmission Electron Microscopy (TEM). For the first time, echostructure, hepatic lobes length, vascular alterations, and indirect signs of hepatic dysfunctions, routinely used as signs of disease in humans, have been analyzed in an immunocompromised murine model. Our findings showed echostructural alterations in all infected mice compared with the Phosphate Buffer Solution (PBS) control group; further, those infected with B. henselae and co-infected with B. henselae/B. fragilis ΔPSA presented the major echostructural alterations. Half of the mice infected with B. henselae and all those co-infected with B. henselae/B. fragilis ΔPSA have showed an altered hepatic echogenicity compared with the renal cortex. The echogenicity score of co-infected mice with B. henselae/B. fragilis ΔPSA differed significantly compared with the PBS control group (p < 0.05). Moreover the inflammation score of the histopathological evaluation was fairly concordant with ultrasound findings. Ultrastructural analysis performed by TEM revealed no significant alterations in liver samples of SCID mice infected with B. fragilis wild type while those infected with B. fragilis ΔPSA showed the presence of collagen around the main vessels compared with the PBS control group. The liver samples of mice infected with B. henselae showed macro-areas rich in collagen, stellate cells, and histiocytic cells. Interestingly, our data demonstrated that immunocompromised SCID mice infected with B. henselae and co-infected with B. henselae/B. fragilis ΔPSA showed the most severe morpho-structural liver damage. In addition, these results suggests that the HFUS together with histopathological evaluation could be considered good imaging approach to evaluate hepatic alterations.

18.
Artigo em Inglês | MEDLINE | ID: mdl-26925256

RESUMO

Human intravenous immune globulin (IVIg), a purified IgG fraction composed of ~ 60% IgG1 and obtained from the pooled plasma of thousands of donors, is clinically used for a wide range of diseases. The biological actions of IVIg are incompletely understood and have been attributed both to the polyclonal antibodies therein and also to their IgG (IgG) Fc regions. Recently, we demonstrated that multiple therapeutic human IgG1 antibodies suppress angiogenesis in a target-independent manner via FcγRI, a high-affinity receptor for IgG1. Here we show that IVIg possesses similar anti-angiogenic activity and inhibited blood vessel growth in five different mouse models of prevalent human diseases, namely, neovascular age-related macular degeneration, corneal neovascularization, colorectal cancer, fibrosarcoma and peripheral arterial ischemic disease. Angioinhibition was mediated by the Fc region of IVIg, required FcγRI and had similar potency in transgenic mice expressing human FcγRs. Finally, IVIg therapy administered to humans for the treatment of inflammatory or autoimmune diseases reduced kidney and muscle blood vessel densities. These data place IVIg, an agent approved by the US Food and Drug Administration, as a novel angioinhibitory drug in doses that are currently administered in the clinical setting. In addition, they raise the possibility of an unintended effect of IVIg on blood vessels.

19.
Thyroid ; 26(4): 552-8, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26844598

RESUMO

BACKGROUND: Thyroid carcinoma is the most common endocrine malignancy and has an increasing incidence. High-frequency ultrasound (HFUS) has a spatial resolution of 30 µm, which is a property that has been exploited for thyroid visualization and analysis in mice. The aim of this study was to generate a novel orthotopic mouse model of human follicular thyroid carcinoma (FTC) using an HFUS-guided injection system. METHODS: Twenty Balb/C nude mice were injected in the right lobe of the thyroid with 2 × 10(6) FTC-133 cells using the microinjection HFUS-guided system, and 20 mice, used as a control, underwent surgical orthotopic implantation of 2 × 10(6) FTC-133 cells in the right lobe of the thyroid. All mice underwent HFUS imaging two weeks after cell injection; HFUS examinations and tumor volume (TV) measurements were repeated weekly. Micro-computed tomography was performed at different time points to determine whether lung metastasis had occurred. TVs were compared between the two models (surgical vs. HFUS-guided) using the Mann-Whitney U-test, and the Mantel-Cox log-rank test was applied to evaluate the death hazard. Hematoxylin and eosin analysis of formalin-fixed, paraffin-embedded mouse tissue was performed to validate the in vivo imaging results. RESULTS: Of the HFUS-guided injected mice, 9/18 survived up to 40 days after the injection of tumor cells. Mice injected surgically had 100% mortality at day 29. Of 38 mice, 29 (14/18 HFUS, 15/20 surgical) showed metastasis in the salivary glands and lymph nodes, and 13 (10/18 HFUS, 3/20 surgical) also showed metastasis in the lungs, which was confirmed by histological analysis. In the surgical group, there was an evident, frequent (12/20 mice) involvement of the contralateral lobe of the thyroid, whereas this feature was only detected in 1/18 mice in the HFUS group. Statistical analysis showed the same pattern of growth in the two groups, and a significant hazard in the mice in the surgical group (p = 0.03). CONCLUSIONS: This study demonstrated the technical feasibility of an HFUS-guided orthotopic mouse model of FTC. The HFUS-guided orthotopic model is easily reproducible and allows prolonged monitoring of the disease because the animals showed an increased survival rate.


Assuntos
Adenocarcinoma Folicular/diagnóstico por imagem , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Ultrassonografia/métodos , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Feminino , Humanos , Incidência , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Metástase Neoplásica , Transplante de Neoplasias , Modelos de Riscos Proporcionais , Taxa de Sobrevida , Microtomografia por Raio-X
20.
Oncotarget ; 7(15): 19531-47, 2016 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-26799668

RESUMO

Glioblastoma is the most common primary brain tumor in adults; with a survival rate of 12 months from diagnosis. However, a small subgroup of patients, termed long-term survivors (LTS), has a survival rate longer then 12-14 months. There is thus increasing interest in the identification of molecular signatures predicting glioblastoma prognosis and in how to improve the therapeutic approach. Here, we report miR-340 as prognostic tumor-suppressor microRNA for glioblastoma. We analyzed microRNA expression in > 500 glioblastoma patients and found that although miR-340 is strongly down-regulated in glioblastoma overall, it is up-regulated in LTS patients compared to short-term survivors (STS). Indeed, miR-340 expression predicted better prognosis in glioblastoma patients. Coherently, overexpression of miR-340 in glioblastoma cells was found to produce a tumor-suppressive activity. We identified NRAS mRNA as a critical, direct target of miR-340: in fact, miR-340 negatively influenced multiple aspects of glioblastoma tumorigenesis by down-regulating NRAS and downstream AKT and ERK pathways. Thus, we demonstrate that expression of miR-340 in glioblastoma is responsible for a strong tumor-suppressive effect in LTS patients by down-regulating NRAS. miR-340 may thus represent a novel marker for glioblastoma diagnosis and prognosis, and may be developed into a tool to improve treatment of glioblastoma.


Assuntos
Neoplasias Encefálicas/genética , Regulação para Baixo , GTP Fosfo-Hidrolases/genética , Regulação Neoplásica da Expressão Gênica , Glioblastoma/genética , Proteínas de Membrana/genética , MicroRNAs/genética , Regiões 3' não Traduzidas/genética , Células A549 , Animais , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Feminino , GTP Fosfo-Hidrolases/metabolismo , Genes Supressores de Tumor , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Estimativa de Kaplan-Meier , Células MCF-7 , Proteínas de Membrana/metabolismo , Camundongos Nus , Prognóstico , Sobreviventes , Transplante Heterólogo
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