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1.
J Anat ; 244(5): 873-881, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38111134

RESUMO

OBJECTIVES: The presence of prostate-specific antigen (PSA) in saliva and salivary glands has been reported. Nevertheless, its release pathway in these glands remains to be elucidated. Here, we showed PSA subcellular distribution focusing on its plausible route in human salivary parenchyma. MATERIALS AND METHODS: Sections of parotid and submandibular glands were subjected to the immunohistochemical demonstration of PSA by the streptavidin-biotin method revealed by alkaline phosphatase. Moreover, ultrathin sections were collected on nickel grids and processed for immunocytochemical analysis, to visualize the intracellular distribution pattern of PSA through the observation by transmission electron microscopy. RESULTS: By immunohistochemistry, in both parotid and submandibular glands PSA expression was detected in serous secretory acini and striated ducts. By immunocytochemistry, immunoreactivity was retrieved in the cytoplasmic compartment of acinar and ductal cells, often associated with small cytoplasmic vesicles. PSA labeling appeared also on rough endoplasmic reticulum and in the acini's lumen. A negligible PSA labeling appeared in most of the secretory granules of both glands. CONCLUSIONS: Our findings clearly support that human parotid and submandibular glands are involved in PSA secretion. Moreover, based on the immunoreactivity pattern, its release in oral cavity would probably occur by minor regulated secretory or constitutive-like secretory pathways.


Assuntos
Antígeno Prostático Específico , Glândulas Salivares , Humanos , Masculino , Imuno-Histoquímica , Glândula Parótida/ultraestrutura , Antígeno Prostático Específico/metabolismo , Glândulas Salivares/ultraestrutura , Glândula Submandibular/metabolismo
2.
Int J Mol Sci ; 24(5)2023 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-36901760

RESUMO

Pterygium is a multifactorial disease in which UV-B is speculated to play a key role by inducing oxidative stress and phototoxic DNA damage. In search for candidate molecules that are useful for justifying the intense epithelial proliferation observed in pterygium, our attention has been focused on Insulin-like Growth Factor 2 (IGF-2), mainly detected in embryonic and fetal somatic tissues, which regulate metabolic and mitogenic functions. The binding between IGF-2 and its receptor Insulin-like Growth Factor 1 Receptor (IGF-1R) activates the PI3K-AKT pathway, which leads to the regulation of cell growth, differentiation, and the expression of specific genes. Since IGF2 is regulated by parental imprinting, in different human tumors, the IGF2 Loss of Imprinting (LOI) results in IGF-2- and IGF2-derived intronic miR-483 overexpression. Based on these activities, the purpose of this study was to investigate the overexpression of IGF-2, IGF-1R, and miR-483. Using an immunohistochemical approach, we demonstrated an intense colocalized epithelial overexpression of IGF-2 and IGF-1R in most pterygium samples (Fisher's exact test, p = 0.021). RT-qPCR gene expression analysis confirmed IGF2 upregulation and demonstrated miR-483 expression in pterygium compared to normal conjunctiva (253.2-fold and 12.47-fold, respectively). Therefore, IGF-2/IGF-1R co-expression could suggest their interplay through the two different paracrine/autocrine IGF-2 routes for signaling transfer, which would activate the PI3K/AKT signaling pathway. In this scenario, miR-483 gene family transcription might synergically reinforce IGF-2 oncogenic function through its boosting pro-proliferative and antiapoptotic activity.


Assuntos
MicroRNAs , Pterígio , Humanos , Proliferação de Células , Túnica Conjuntiva/metabolismo , Fator de Crescimento Insulin-Like II/metabolismo , MicroRNAs/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor IGF Tipo 1/metabolismo
3.
Front Oncol ; 11: 635488, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34123788

RESUMO

Cutaneous melanoma is an aggressive tumor responsible for 90% of mortality related to skin cancer. In the recent years, the discovery of driving mutations in melanoma has led to better treatment approaches. The last decade has seen a genomic revolution in the field of cancer. Such genomic revolution has led to the production of an unprecedented mole of data. High-throughput genomic technologies have facilitated the genomic, transcriptomic and epigenomic profiling of several cancers, including melanoma. Nevertheless, there are a number of newer genomic technologies that have not yet been employed in large studies. In this article we describe the current classification of cutaneous melanoma, we review the current knowledge of the main genetic alterations of cutaneous melanoma and their related impact on targeted therapies, and we describe the most recent high-throughput genomic technologies, highlighting their advantages and disadvantages. We hope that the current review will also help scientists to identify the most suitable technology to address melanoma-related relevant questions. The translation of this knowledge and all actual advancements into the clinical practice will be helpful in better defining the different molecular subsets of melanoma patients and provide new tools to address relevant questions on disease management. Genomic technologies might indeed allow to better predict the biological - and, subsequently, clinical - behavior for each subset of melanoma patients as well as to even identify all molecular changes in tumor cell populations during disease evolution toward a real achievement of a personalized medicine.

4.
World J Stem Cells ; 13(12): 1918-1927, 2021 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-35069990

RESUMO

BACKGROUND: One of the most challenging tasks of modern biology concerns the real-time tracking and quantification of mRNA expression in living cells. On this matter, a novel platform called SmartFlareTM has taken advantage of fluorophore-linked nanoconstructs for targeting RNA transcripts. Although fluorescence emission does not account for the spatial mRNA distribution, NanoFlare technology has grown a range of theranostic applications starting from detecting biomarkers related to diseases, such as cancer, neurodegenerative pathologies or embryonic developmental disorders. AIM: To investigate the potential of SmartFlareTM in determining time-dependent mRNA expression of prominin 1 (CD133) and octamer-binding transcription factor 4 (OCT4) in single living cells through differentiation. METHODS: Brain fragments from the striatum of aborted human fetuses aged 8 wk postconception were processed to obtain neurospheres. For the in vitro differentiation, neurospheres were gently dissociated with Accutase solution. Single cells were resuspended in a basic medium enriched with fetal bovine serum, plated on poly-L-lysine-coated glass coverslips, and grown in a lapse of time from 1 to 4 wk. Live cell mRNA detection was performed using SmartFlareTM probes (CD133, Oct4, Actin, and Scramble). All the samples were incubated at 37 °C for 24 h. For nuclear staining, Hoechst 33342 was added. SmartFlareTM CD133- and OCT4-specific fluorescence signal was assessed using a semiquantitative visual approach, taking into account the fluorescence intensity and the number of labeled cells. RESULTS: In agreement with previous PCR experiments, a unique expression trend was observed for CD133 and OCT4 genes until 7 d in vitro (DIV). Fluorescence resulted in a mixture of diffuse cytoplasmic and spotted-like pattern, also detectable in the contacting neural branches. From 15 to 30 DIV, only few cells showed a scattered fluorescent pattern, in line with the differentiation progression and coherent with mRNA downregulation of these stemness-related genes. CONCLUSION: SmartFlareTM appears to be a reliable, easy-to-handle tool for investigating CD133 and OCT4 expression in a neural stem cell model, preserving cell biological properties in anticipation of downstream experiments.

5.
Int J Mol Sci ; 21(24)2020 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-33348804

RESUMO

Stemness and apoptosis may highlight the dichotomy between regeneration and demise in the complex pathway proceeding from ontogenesis to the end of life. In the last few years, the concept has emerged that the same microRNAs (miRNAs) can be concurrently implicated in both apoptosis-related mechanisms and cell differentiation. Whether the differentiation process gives rise to the architecture of brain areas, any long-lasting perturbation of miRNA expression can be related to the occurrence of neurodevelopmental/neuropathological conditions. Moreover, as a consequence of neural stem cell (NSC) transformation to cancer stem cells (CSCs), the fine modulation of distinct miRNAs becomes necessary. This event implies controlling the expression of pro/anti-apoptotic target genes, which is crucial for the management of neural/neural crest-derived CSCs in brain tumors, neuroblastoma, and melanoma. From a translational point of view, the current progress on the emerging miRNA-based neuropathology therapeutic applications and antitumor strategies will be disclosed and their advantages and shortcomings discussed.


Assuntos
Apoptose , Diferenciação Celular , MicroRNAs/genética , Neoplasias/patologia , Células-Tronco Neoplásicas/patologia , Células-Tronco Neurais/patologia , Animais , Humanos , Neoplasias/genética , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neurais/metabolismo
6.
Plants (Basel) ; 9(8)2020 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-32751574

RESUMO

Polyphenol oxidase (PPO, E.C. 1.14.18.1) is a nearly ubiquitous enzyme that is widely distributed among organisms. Despite its widespread distribution, the role of PPO in plants has not been thoroughly elucidated. In this study, we report for the absence of PPO in Cynomorium coccineum, a holoparasitic plant adapted to withstand unfavorable climatic conditions, growing in Mediterranean countries and amply used in traditional medicine. The lack of PPO has been demonstrated by the absence of enzymatic activity with various substrates, by the lack of immunohistochemical detection of the enzyme, and by the absence of the PPO gene and, consequently, its expression. The results obtained in our work allow us to exclude the presence of the PPO activity (both latent and mature forms of the enzyme), as well as of one or more genes coding for PPO in C. coccineum. Finally, we discuss the possible significance of PPO deficiency in parasitic plants adapted to abiotic stress.

7.
J Transl Med ; 18(1): 192, 2020 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-32393282

RESUMO

BACKGROUND: Most mutations in melanoma affect one critical amino acid on BRAF gene, resulting in the V600E substitution. Patient management is often based on the use of specific inhibitors targeting this mutation. METHODS: DNA and RNA mutation status was assessed in 15 melanoma cell lines by Sanger sequencing and RNA-seq. We tested the cell lines responsiveness to BRAF inhibitors (vemurafenib and PLX4720, BRAF-specific and sorafenib, BRAF non-specific). Cell proliferation was assessed by MTT colorimetric assay. BRAF V600E RNA expression was assessed by qPCR. Expression level of phosphorylated-ERK protein was assessed by Western Blotting as marker of BRAF activation. RESULTS: Three cell lines were discordant in the mutation detection (BRAF V600E at DNA level/Sanger sequencing and BRAF WT on RNA-seq). We initially postulated that those cell lines may express only the WT allele at the RNA level although mutated at the DNA level. A more careful analysis showed that they express low level of BRAF RNA and the expression may be in favor of the WT allele. We tested whether the discordant cell lines responded differently to BRAF-specific inhibitors. Their proliferation rate decreased after treatment with vemurafenib and PLX4720 but was not affected by sorafenib, suggesting a BRAF V600E biological behavior. Yet, responsiveness to the BRAF specific inhibitors was lower as compared to the control. Western Blot analysis revealed a decreased expression of p-ERK protein in the BRAF V600E control cell line and in the discordant cell lines upon treatment with BRAF-specific inhibitors. The discordant cell lines showed a lower responsiveness to BRAF inhibitors when compared to the BRAF V600E control cell line. The results obtained from the inhibition experiment and molecular analyses were also confirmed in three additional cell lines. CONCLUSION: Cell lines carrying V600E mutation at the DNA level may respond differently to BRAF targeted treatment potentially due to a lower V600E RNA expression.


Assuntos
Melanoma , Proteínas Proto-Oncogênicas B-raf , Linhagem Celular Tumoral , Humanos , Melanoma/tratamento farmacológico , Melanoma/genética , Mutação/genética , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas B-raf/genética , Vemurafenib/farmacologia
8.
Int J Mol Sci ; 20(17)2019 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-31450858

RESUMO

MicroRNAs, also called miRNAs or simply miR-, represent a unique class of non-coding RNAs that have gained exponential interest during recent years because of their determinant involvement in regulating the expression of several genes. Despite the increasing number of mature miRNAs recognized in the human species, only a limited proportion is engaged in the ontogeny of the central nervous system (CNS). miRNAs also play a pivotal role during the transition of normal neural stem cells (NSCs) into tumor-forming NSCs. More specifically, extensive studies have identified some shared miRNAs between NSCs and neural cancer stem cells (CSCs), namely miR-7, -124, -125, -181 and miR-9, -10, -130. In the context of NSCs, miRNAs are intercalated from embryonic stages throughout the differentiation pathway in order to achieve mature neuronal lineages. Within CSCs, under a different cellular context, miRNAs perform tumor suppressive or oncogenic functions that govern the homeostasis of brain tumors. This review will draw attention to the most characterizing studies dealing with miRNAs engaged in neurogenesis and in the tumoral neural stem cell context, offering the reader insight into the power of next generation miRNA-targeted therapies against brain malignances.


Assuntos
MicroRNAs/genética , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neurais/metabolismo , Animais , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Diferenciação Celular/genética , Perfilação da Expressão Gênica , Humanos , Células-Tronco Neoplásicas/patologia , Neurogênese/genética , Transcriptoma
9.
Histochem Cell Biol ; 151(2): 175-185, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30232588

RESUMO

While histological analysis represents a powerful tool for the classification of melanocytic lesions as benign or malignant, a clear-cut distinction between a nevus and a melanoma is sometimes a challenging step of the diagnostic process. The immunohistochemical detection of tyrosinase, cardinal melanogenic enzyme during melanocytic maturation, has often been helpful in formulating a differential diagnosis due to the peculiar staining pattern in nevocytes compared with melanoma cells. Tyrosinase distribution in nevi appears to overlap with the cytoarchitectural changes observable within these lesions, that result in epidermal or superficial dermal nevocytes being larger and strongly expressing melanocytic differentiation antigens, such as tyrosinase, compared with deeper dermal nevus cells. Our study aimed to evaluate the immunohistochemical expression pattern of tyrosinase in different histological types of acquired dysplastic melanocytic nevi, including junctional, compound, and intradermal nevi. Moreover, to estimate whether in nevocytes the expression of tyrosinase was associated with their differentiation state, we investigated the expression of two recognized markers of pluripotency, CD34 and nestin. In all examined nevi, our analysis revealed a remarkable immunoreactivity for tyrosinase in junctional and superficial dermal nevocytes and a decreasing gradient of staining in dermal nevocytes, up to become negative in deeper dermis. Meanwhile, junctional and dermal nevocytes were lacking in CD34 protein. Furthermore, nestin immunostaining showed an opposite distribution compared with tyrosinase, leading us to look into the tyrosinase/nestin expression pattern in melanocytic nevus as a tool to better understand the final stages of differentiation of melanocyte precursors toward their ultimate anatomical site into the epidermis.


Assuntos
Diferenciação Celular , Melanócitos/química , Melanócitos/patologia , Monofenol Mono-Oxigenase/análise , Nestina/análise , Nevo Pigmentado/química , Nevo Pigmentado/patologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Imuno-Histoquímica , Masculino , Melanócitos/metabolismo , Pessoa de Meia-Idade , Monofenol Mono-Oxigenase/biossíntese , Nestina/biossíntese , Nevo Pigmentado/metabolismo , Adulto Jovem
11.
Neuropharmacology ; 144: 219-232, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30366005

RESUMO

Methoxetamine (MXE) is a novel psychoactive substance that can induce several short-term effects on emotional states and behavior. However, little is known about the persistent emotional and behavioral effects of MXE. Moreover, neurotoxic effects of MXE have been hypothesized, but never demonstrated in vivo. To clarify these issues, rats received repeated treatment with MXE every other day (0.1-0.5 mg/kg, i.p., × 5), and 7 days later they were challenged with MXE (0.1-0.5 mg/kg, i.p.). Behavioral effects of MXE were first evaluated by measuring emission of ultrasonic vocalizations and locomotor activity after each administration. Thereafter, persistent behavioral effects of MXE were evaluated, starting 8 days after challenge, through elevated plus maze, spontaneous alternation, novel object recognition, and marble burying tests. After completion of behavioral analysis, neurotoxic effects of MXE were evaluated by measuring densities of dopamine transporter, tyrosine hydroxylase, and serotonin transporter in various brain regions. Repeated treatment and challenge with MXE affected neither calling behavior nor locomotor activity of rats. Conversely, rats previously treated with MXE exhibited behavioral alterations in the elevated plus maze, marble burying and novel object recognition tests, suggestive of increased anxiety and impaired non-spatial memory. Noteworthy, the same rats displayed dopaminergic damage in the medial prefrontal cortex, nucleus accumbens, caudate-putamen, substantia nigra pars compacta, and ventral tegmental area, along with accumbal serotonergic damage. Our findings show for the first time that repeated administration of MXE induces persistent behavioral abnormalities and neurotoxicity in rats, which can help elucidating the risks associated with human MXE consumption.


Assuntos
Comportamento Animal/efeitos dos fármacos , Cicloexanonas/efeitos adversos , Cicloexilaminas/efeitos adversos , Síndromes Neurotóxicas , Neurotoxinas/efeitos adversos , Psicotrópicos/efeitos adversos , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Relação Dose-Resposta a Droga , Emoções/efeitos dos fármacos , Masculino , Memória/efeitos dos fármacos , Atividade Motora/efeitos dos fármacos , Síndromes Neurotóxicas/metabolismo , Síndromes Neurotóxicas/patologia , Síndromes Neurotóxicas/psicologia , Proteínas de Ligação a RNA/metabolismo , Ratos Sprague-Dawley , Tirosina 3-Mono-Oxigenase/metabolismo
12.
Neurobiol Aging ; 69: 117-128, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29890391

RESUMO

Epidemiological evidence suggests a correlation between diabetes and age-related neurodegenerative disorders, including Alzheimer's and Parkinson's diseases. Hyperglycemia causes oxidative stress in vulnerable tissues such as the brain. We recently demonstrated that elevated levels of glucose lead to the death of dopaminergic neurons in culture through oxidative mechanisms. Considering the lack of literature addressing dopaminergic alterations in diabetes with age, the goal of this study was to characterize the state of 2 critical dopaminergic pathways in the nicotinamide-streptozotocin rat model of long-term hyperglycemia, specifically the nigrostriatal motor pathway and the reward-associated mesocorticolimbic pathway. Neuronal and glial alterations were evaluated 3 and 6 months after hyperglycemia induction, demonstrating preferential degeneration of the nigrostriatal pathway complemented by a noticeable astrogliosis and loss of microglial cells throughout aging. Behavioral tests confirmed the existence of motor impairments in hyperglycemic rats that resemble early parkinsonian symptomatology in rats, pensuing from nigrostriatal alterations. These results solidify the relation between hyperglycemia and nigrostriatal dopaminergic neurodegeneration, providing new insight on the higher occurrence of Parkinson's disease in diabetic patients.


Assuntos
Corpo Estriado/patologia , Neurônios Dopaminérgicos/patologia , Hiperglicemia/patologia , Parte Compacta da Substância Negra/patologia , Animais , Diabetes Mellitus/patologia , Modelos Animais de Doenças , Gliose/etiologia , Hiperglicemia/induzido quimicamente , Hiperglicemia/complicações , Masculino , Atividade Motora , Vias Neurais/patologia , Doença de Parkinson/patologia , Ratos Sprague-Dawley
13.
Mol Vis ; 24: 853-866, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30713424

RESUMO

Purpose: Telocytes (TCs) are peculiar interstitial cells, characterized by their typical elongated and interconnected processes called telopodes. TCs are supposed to contribute to maintain tissue homeostasis but also to be involved in the pathophysiology of many disorders. The aim of the study was to identify TCs in pterygium, a chronic condition of bulbar conjunctiva, and to examine possible differences in TCs in terms of immunophenotype and/or localization between pterygium and normal conjunctiva, to evaluate the possible involvement of TCs in pathogenesis of pterygium. Methods: The analysis of the immunophenotype of TCs was performed on a group of 40 formalin-fixed and paraffin-embedded primary pterygium and ten bulbar conjunctiva samples. We examined with immunohistochemistry the expression of 11 commercially available antibodies (PDGFRα, CD34, c-kit, nestin, vimentin, α-SMA, laminin, S100, VEGF, CD133, and CD31) and with double immunofluorescence the concomitant expression of PDGFRα and CD34, and PDGFRα and nestin. In addition, we performed an ultrastructural study with transmission electron microscopy (TEM) on a group of five pterygium and three conjunctiva biopsy specimens. Results: TCs, ultrastructurally identified according to their "moniliform" prolongations, were localized underneath the epithelium along the basement membrane, around the vessels, and near the nerves and scattered in the stroma. In contrast, TCs, as fibroblasts, were almost absent in the fibrotic areas. In pterygium and normal conjunctiva, the TCs shared the same distribution pattern, except a marked TC hyperplasia detected in pterygium. Moreover, in pterygium, the immunohistochemical analysis of TCs showed a strong immunoreactivity to PDGFRα, CD34, and nestin. This result was confirmed with double immunofluorescence labeling, revealing that in pterygium stromal TCs always showed a PDGFRα+/nestin+ and PDGFRα+/CD34+ immunophenotype. Furthermore, moderate staining to vimentin and VEGF was detected, but only a small number of cells were weakly immunoreactive to laminin and S100. Only adventitial TCs of the perivascular sheaths exhibited strong immunoreactivity to α-SMA. Conversely, despite showing mild immunoreactivity to PDGFRα and CD34, the TCs in normal conjunctiva did not show any immunoreactivity to nestin and VEGF. Moreover, in pterygium and conjunctiva, the TCs were always negative for c-kit. Conclusions: Because of the distribution and immunophenotype, TCs in pterygium may represent a subpopulation of relatively immature cells with regenerative potential. In addition, the expression of nestin may suggest possible involvement of TCs as active players in the regeneration of ultraviolet-damaged stroma and vascular remodeling. The fibrotic transformation in the cicatricial area may stand for a breakdown of the regenerative process.


Assuntos
Túnica Conjuntiva/anormalidades , Imunofenotipagem/métodos , Pterígio/genética , Telócitos/classificação , Telócitos/metabolismo , Antígeno AC133/genética , Antígeno AC133/metabolismo , Actinas/genética , Actinas/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos CD34/genética , Antígenos CD34/metabolismo , Túnica Conjuntiva/metabolismo , Túnica Conjuntiva/patologia , Túnica Conjuntiva/cirurgia , Feminino , Formaldeído , Expressão Gênica , Humanos , Imuno-Histoquímica , Laminina/genética , Laminina/metabolismo , Masculino , Pessoa de Meia-Idade , Nestina/genética , Nestina/metabolismo , Molécula-1 de Adesão Celular Endotelial a Plaquetas/genética , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Proteínas Proto-Oncogênicas c-kit/genética , Proteínas Proto-Oncogênicas c-kit/metabolismo , Pterígio/metabolismo , Pterígio/patologia , Pterígio/cirurgia , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/genética , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Proteínas S100/genética , Proteínas S100/metabolismo , Telócitos/patologia , Fixação de Tecidos , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Vimentina/genética , Vimentina/metabolismo
14.
Histochem Cell Biol ; 148(6): 639-649, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28828681

RESUMO

Epithelial-mesenchymal transition (EMT) has been suggested to have a driving role in the acquisition of a metastatic potential by melanoma cells. Important hallmarks of EMT include both E-cadherin downregulation and increased expression of N-cadherin. This switch in distinct classes of adhesion molecules leads melanoma cells to lose contact with adjacent keratinocytes and interact instead with stromal fibroblasts and endothelial cells, thus promoting dermal and vascular melanoma invasion. Consequently, tumor cells migrate to distant host tissues and establish metastases. A key regulator in the induction of EMT in melanoma is the Notch1 signaling pathway that, when activated, is prompt to upregulate N-cadherin expression. By means of this strategy, melanoma cells gain enhanced survival, proliferation and invasion properties, driving the tumor toward a more aggressive phenotype. On the basis of these statements, the present study aimed to investigate the possible association between N-cadherin and Notch1 presence in primary cutaneous melanomas and lymph node metastases. Our results from immunohistochemical analysis confirmed a positive correlation between N-cadherin and Notch1 presence in the same tumor samples. Moreover, this study highlighted that a concomitant high expression of N-cadherin and Notch1, both in primary lesions and in lymph node metastases, predicts an adverse clinical outcome in melanoma patients. Therefore, N-cadherin and Notch1 co-presence can be monitored as a predictive factor in early- and advanced-stage melanomas and open additional therapeutic targets for the restraint of melanoma metastasis.


Assuntos
Caderinas/análise , Transição Epitelial-Mesenquimal , Melanoma/química , Receptor Notch1/análise , Neoplasias Cutâneas/química , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Caderinas/biossíntese , Criança , Feminino , Humanos , Imuno-Histoquímica , Masculino , Melanoma/diagnóstico , Melanoma/metabolismo , Pessoa de Meia-Idade , Receptor Notch1/biossíntese , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/metabolismo , Adulto Jovem
15.
Eur J Histochem ; 61(4): 2837, 2017 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-29313597

RESUMO

Pterygium, an ultraviolet radiation (UV)-related disease, is a relatively benign process, but since it displays tumor-like features, it has been proposed to be a neoplastic- like growth disorder. Vitamin D performs a number of functions in addition to calcium homeostasis, as inhibition of cell proliferation, activation of apoptotic pathways, and inhibition of angiogenesis. Since the antitumor actions of vitamin D are mediated primarily through the nuclear vitamin D receptor (VDR), the aim of the present study was to investigate vitamin D status in patients with pterygium and in control subjects, and VDR immunohistochemical expression in samples of pterygium and normal conjunctiva in order to evaluate a possible role of vitamin D pathway in the pathogenesis of the disease. Serum vitamin D concentration was measured among 41 patients with pterygium and 47 volunteers by an automated chemiluminescence immunoassay. Moreover, 23 formalin- fixed and paraffin-embedded pterygium biopsy samples and 24 conjunctiva specimens were treated for the immunohistochemical demonstration of VDR using the streptavidin-biotin alkaline phosphatase method. No differences were observed about vitamin D level between patient with pterygium and control group, but significant differences between VDR immunolocalization in pterygium and normal conjunctiva were observed (P=0.00001). In conjunctiva, the immunoreactivity, localized mainly in cytoplasm of epithelial cells, may probably demonstrate VDR regulation of cell growth, differentiation, and apoptosis, while in pterygium VDR co-localization in the nucleus and cytoplasm of epithelial cells may indicate alternative nuclear pathways by which vitamin D might exert its antiinflammatory and anti-proliferative effects by the regulation of gene expression.


Assuntos
Pterígio/fisiopatologia , Receptores de Calcitriol/metabolismo , Vitamina D/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Túnica Conjuntiva/química , Túnica Conjuntiva/fisiopatologia , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Vitamina D/metabolismo
16.
Clin Exp Med ; 15(3): 351-60, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25034654

RESUMO

An early event in melanocytic tumor growth is the upregulation of Notch signaling. When an active form of Notch1 is overexpressed in primary human melanocytes, it increases cell growth, survival and invasive properties, promoting melanoma progression. Recent evidence suggested that tumor initiation and growth are driven by a subset of tumor-initiating cells termed cancer stem cells. Notch1 plays a predominant role in the maintenance of melanoblasts, including melanocyte stem cells, by preventing initiation of apoptosis. Moreover, the importance of Notch1 in the regulation of tumor angiogenesis is supported by growing evidence in various cancers. Nestin has been widely used as a marker for melanocyte stem cells as well as an angiogenic marker to evaluate neovascularity of endothelial cells in tumors. To gain an insight into the impact of Notch1 activation on the maintenance of melanocyte stem cells and angiogenesis in melanoma, the expression levels of activated Notch1 and nestin were analyzed by immunohistochemistry in 114 primary cutaneous melanomas and 35 lymph node metastases. Activated Notch1 and nestin expression was also evaluated in four dysplastic melanocytic nevi. This study provides evidence that activated Notch1 is overexpressed in cutaneous melanoma, in tumor cells as well as in microvessel endothelium, and that it can promote tumor angiogenesis. Indeed, the overexpression of activated Notch1 in both tumor and vascular endothelial cells was significantly associated with microvascular density in melanoma samples. Thus, activated Notch1 inhibitors may provide a therapeutic strategy in the treatment of melanoma by blocking tumor-associated vascularization.


Assuntos
Melanoma/patologia , Neovascularização Patológica , Receptor Notch1/análise , Neoplasias Cutâneas/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Imuno-Histoquímica , Linfonodos/patologia , Masculino , Microscopia , Pessoa de Meia-Idade , Metástase Neoplásica/patologia , Nestina/análise
17.
BMJ Open ; 4(10): e005627, 2014 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-25341451

RESUMO

OBJECTIVE: The purpose of the study was to examine whether the insertion (I) and/or deletion (D) polymorphism of ACE confers susceptibility to primary pterygium in Sardinian patients in a case-control study. METHODS AND RESULTS: Polymorphism genotyping was performed by nested PCR using genomic DNA extracted from the whole peripheral blood of participants with (n=251) and without (n=260) pterygium. DD, ID and II genotype frequencies were: 48%, 39% and 13%, respectively, for patients with pterygium, and 15%, 40% and 44%, respectively, for the control group. A statistically significant difference was found between the pterygium and control groups for the ACE I/D polymorphism (p<0.001). Moreover, a statistically significant difference was found between the DD and II groups (p<0.01; OR=10.49; 95% CI 6.18 to 17.79), DD+ID versus II group (p<0.01; OR=5.23; 95% CI 3.37 to 8.13) and DD versus ID groups (p<0.01; OR=3.21; 95% CI 2.04 to 5.04). CONCLUSIONS: Statistical analysis showed that the DD genotype is associated with an increased risk of developing pterygium, and with a good chance that the D allele may play an important role in the development of disease.


Assuntos
Peptidil Dipeptidase A/genética , Pterígio/genética , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Deleção de Genes , Humanos , Mutação INDEL , Itália , Masculino , Pessoa de Meia-Idade , Mutagênese Insercional , População Branca/genética
18.
J Clin Invest ; 124(5): 2147-59, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24691438

RESUMO

In multiple forms of cancer, constitutive activation of type I IFN signaling is a critical consequence of immune surveillance against cancer; however, PBMCs isolated from cancer patients exhibit depressed STAT1 phosphorylation in response to IFN-α, suggesting IFN signaling dysfunction. Here, we demonstrated in a coculture system that melanoma cells differentially impairs the IFN-α response in PBMCs and that the inhibitory potential of a particular melanoma cell correlates with NOS1 expression. Comparison of gene transcription and array comparative genomic hybridization (aCGH) between melanoma cells from different patients indicated that suppression of IFN-α signaling correlates with an amplification of the NOS1 locus within segment 12q22-24. Evaluation of NOS1 levels in melanomas and IFN responsiveness of purified PBMCs from patients indicated a negative correlation between NOS1 expression in melanomas and the responsiveness of PBMCs to IFN-α. Furthermore, in an explorative study, NOS1 expression in melanoma metastases was negatively associated with patient response to adoptive T cell therapy. This study provides a link between cancer cell phenotype and IFN signal dysfunction in circulating immune cells.


Assuntos
Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Interferon-alfa/metabolismo , Melanoma/metabolismo , Proteínas de Neoplasias/biossíntese , Óxido Nítrico Sintase Tipo I/biossíntese , Transdução de Sinais , Transferência Adotiva , Linhagem Celular Tumoral , Técnicas de Cocultura , Hibridização Genômica Comparativa , Feminino , Perfilação da Expressão Gênica , Humanos , Interferon-alfa/genética , Masculino , Melanoma/genética , Melanoma/patologia , Melanoma/terapia , Proteínas de Neoplasias/genética , Óxido Nítrico Sintase Tipo I/genética , Análise de Sequência com Séries de Oligonucleotídeos
19.
Histopathology ; 62(3): 487-98, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23072594

RESUMO

AIMS: Nestin (a neuronal stem cell/progenitor cell marker of central nervous system development), vimentin (which is ubiquitously expressed in mesenchymal cells), and the glucocorticoid receptor (GR, which is involved in the immune response, cell proliferation, and apoptosis) have been shown to interact in embryonic and undifferentiated tissues in modulating cell proliferation. The aim of this study was to analyse nestin, vimentin and GR expression in tumour tissue (melanoma), and their association with clinicopathological variables, to evaluate any effect on tumour progression. METHODS AND RESULTS: Immunohistochemistry, double-label immunofluorescence and confocal laser scanning microscopy were performed on biopsy specimens of cutaneous melanoma from 81 patients. Fisher's and Pearson's tests showed a correlation between nestin, vimentin and subcellular GR location (P = 0.008). Their concomitant expression also correlated with Clark level and thickness (P = 0.02 and P = 0.029, respectively). Kaplan-Meier analysis revealed a poorer outcome for stage III and IV patients with associated expression of nestin, vimentin and cytoplasmic GR in tumour tissue (P = 0.02). CONCLUSIONS: These results suggest the presence in melanoma of growth mechanisms involving nestin, vimentin, and GR, similarly to that occurring in embryonic and undifferentiated cells, and may help in understanding tumour biology to provide a molecular basis for clinical therapies.


Assuntos
Proteínas de Filamentos Intermediários/metabolismo , Melanoma/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Receptores de Glucocorticoides/metabolismo , Neoplasias Cutâneas/metabolismo , Vimentina/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/análise , Criança , Feminino , Imunofluorescência , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Masculino , Melanoma/mortalidade , Melanoma/patologia , Microscopia Confocal , Pessoa de Meia-Idade , Nestina , Neoplasias Cutâneas/mortalidade , Neoplasias Cutâneas/patologia , Adulto Jovem
20.
J Proteome Res ; 11(10): 5011-21, 2012 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-22909274

RESUMO

High-grade gliomas (glioblastomas) are the most common and deadly brain tumors in adults, currently with no satisfactory treatment available. Apart from de novo glioblastoma, it is currently accepted that these malignancies mainly progress from lower grade glial tumors. However, the molecular entities governing the progression of gliomas are poorly understood. Extracellular and membrane proteins are key biomolecules found at the cell-to-cell communication interface and hence are a promising proteome subpopulation that could help understand the development of glioma. Accordingly, the current study aims at identifying new protein markers of human glioma progression. For this purpose, we used glial tumors generated orthotopically with T98G and U373 human glioma cells in nude mice. This setup allowed also to discriminate the protein origin, namely, human (tumor) or mouse (host). Extracellular and membrane proteins were selectively purified using biotinylation followed by streptavidin affinity chromatography. Isolated proteins were digested and then identified and quantified employing 2D-nano-HPLC-MS/MS analysis. A total of 23 and 27 up-regulated extracellular and membrane proteins were identified in the T98G and U373 models, respectively. Approximately two-thirds of these were predominantly produced by the tumor, whereas the remaining proteins appeared to be mainly overexpressed by the host tissue. Following extensive validation, we have focused our attention on sparc-like protein 1. This protein was further investigated using immunohistochemistry in a large collection of human glioma samples of different grades. The results showed that sparc-like protein 1 expression correlates with glioma grade, suggesting the possible role for this protein in the progression of this malignancy.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Glioblastoma/metabolismo , Animais , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Glioblastoma/patologia , Humanos , Camundongos , Gradação de Tumores , Transplante de Neoplasias
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