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1.
Dent J (Basel) ; 12(6)2024 Jun 05.
Article in English | MEDLINE | ID: mdl-38920873

ABSTRACT

The aim of this study is to validate a minimally invasive surgical procedure to harvest palate periosteum as a source of tissue for mesenchymal stromal/stem cells. We performed a standardized procedure to harvest the palate periosteum in ten subjects, which consisted of a 3 mm disposable punch and a Molt periosteal elevator to harvest a small full-thickness fragment of soft tissue at the hard palate area, between the upper bicuspids, 3 to 4 mm apical to the cement enamel junction. The one-third inner portion was fragmented, and following standard cell culture procedures, the adherent cells were cultured for three passages, after obtaining 70-90% confluence. Cell morphology analysis, flow cytometry analysis, and viability and osteogenic differentiation assays were performed. In all 10 cases, uneventful healing was observed, with no need for analgesic intake. The evaluation of cell morphology showed elongated spindle-shaped cells distributed in woven patterns. A high viability range was verified as well as an immunophenotype compatible with mesenchymal stem cell lineage. The differentiation assay showed the potential of the cells to differentiate into the osteogenic lineage. These results demonstrate that the minimally invasive proposed surgical technique is capable of supplying enough periosteum source tissue for stem cell culture and bone tissue engineering.

2.
Transpl Immunol ; 81: 101919, 2023 12.
Article in English | MEDLINE | ID: mdl-37598913

ABSTRACT

Even though leukemia murine models are valuable tools for new drug therapy studies, most of these models consist of immunocompromised mice, which do not exhibit immune responses. In order to obtain an adequate leukemia model, we established an acute promyelocytic leukemia transplantation-based model (PML/RARa) in immunocompetent BALB/c mice, thus making it possible to study drug-induced cellular immune responses in leukemia. The development of PML/RARa leukemia was confirmed by leukocytosis (76.27 ± 21.8 vs. 3.40 ± 1.06; P < 0.0001), anemia (7.46 ± 1.86 vs. 15.10 ± 0.96; P < 0.0001), and thrombocytopenia (131.85 ± 39.32 vs. 839.50 ± 171.20; P < 0.0001), and the presence of blasts in the peripheral blood of mice (approximately 50% blasts; P < 0.0001), 15 days after the transplants. These findings were corroborated through differential counts, flow cytometry, and in vivo imaging, which indicated increased number of immature cells in the bone marrow (15.75 ± 3.30 vs 6.69 ± 0.55; P < 0.001), peripheral blood (7.88 ± 2.67 vs 1.22 ± 0.89; P < 0.001), and spleen (35.21 ± 4.12 vs 1.35 ± 0.86; P < 0.0001), as well as promyelocytes in the bone marrow (41.23 ± 4.80 vs 5.73 ± 1.50; P < 0.0001), peripheral blood (46.08 ± 7.52 vs 1.10 ± 0.59; P < 0.0001) and spleen (35.31 ± 8.26 vs 2.49 ± 0.29; P < 0.0001) of PML/RARa mice. Compared to basal conditions of untransplanted mice, the PML/RARa mice exhibited frequencies of T lymphocytes CD4 helper = 14.85 ± 2.91 vs 20.77 ± 2.9 in the peripheral blood (P < 0.05); 12.75 ± 1.33 vs 45.90 ± 2.02 in the spleen (P < 0.0001); CD8 cytotoxic = 11.27 ± 3.44 vs 11.05 ± 1.22 in the peripheral blood (P > 0.05); 10.48 ± 1.16 vs 30.02 ± 1.80 in the spleen (P < 0.0001); natural killer (NK) cells = 3.68 ± 1.35 vs 6.84 ± 0.52 in the peripheral blood (P < 0.001); 4.43 ± 0.57 vs 6.40 ± 1.14 in the spleen (P < 0.05); B cells 2.50 ± 0.60 vs 15.20 ± 5.34 in the peripheral blood (P < 0.001); 17.77 ± 4.39 vs 46.90 ± 5.92 in the spleen (P < 0.0001); neutrophils = 5.97% ± 1.88 vs 31.57 ± 9.14 (P < 0.0001); and monocytes = 6.45 ± 2.97 vs 15.85 ± 2.57 (P < 0.001), selected as classical (3.33 ± 3.40 vs 57.80 ± 16.51, P < 0.0001), intermediate (57.42 ± 10.61 vs 21.75 ± 5.90, P < 0.0001), and non-classical monocytes (37.51 ± 10.85 vs 18.08 ± 7.13, P < 0.05) in the peripheral blood; and as classically activated (M1) within in the bone marrow (3.70 ± 0.94 vs 1.88 ± 0.39, P < 0.05) and spleen 15.19 ± 3.32 vs 9.47 ± 1.61, P < 0.05), in addition to alternatively activated (M2) macrophages within the bone marrow (23.06 ± 5.25 vs 1.76 ± 0.74, P < 0.0001) and spleen (46.51 ± 11.18 vs 30.58 ± 2.64, P < 0.05) compartments. All-trans retinoic acid (ATRA) treatment of PML/RARa mice reduced blast (immature cells) in the bone marrow (8.62 ± 1.81 vs 15.76 ± 1.25; P < 0.05) and spleen (8.75 ± 1.31 vs 35.21 ± 1.55; P < 0.0001) with no changes in the peripheral blood (10.13 ± 3.33 vs 7.88 ± 1.01; P > 0.05), as well as reduced promyelocytes in the bone marrow (19.79 ± 4.84 vs 41.23 ± 1.81; P < 0.05), peripheral blood (31.65 ± 3.92 vs 46.09 ± 2.84; P < 0.05) and spleen (24.84 ± 2.03 vs 41.46 ± 2.39; P < 0.001), and increased neutrophils of the peripheral blood (35.48 ± 7.24 vs 7.83 ± 1.40; P < 0.05) which was corroborated by reducing of immature cells and increase of neutrophil in the stained smears from PML/RARa mice, thus confirming that this model can be used in drug development studies. Our results show the effective induction of PML/RARa leukemia in BALB/c mice, thus producing a low-priced and reliable tool for investigating cellular immune responses in leukemia.


Subject(s)
Leukemia, Promyelocytic, Acute , Mice , Animals , Disease Models, Animal , Leukemia, Promyelocytic, Acute/drug therapy , Tretinoin/pharmacology , Retinoic Acid Receptor alpha , Immunotherapy
3.
J Stomatol Oral Maxillofac Surg ; 124(2): 101311, 2023 04.
Article in English | MEDLINE | ID: mdl-36261061

ABSTRACT

BACKGROUND: Despite the advances in the classification of oral squamous cell carcinoma (OSCC) based on its extension by the TNM system, there is still a need for methods to better classify the patients to predict prognosis and indicate adjuvant therapy. OBJECTIVES: To analyze the influence of the number of positive lymph nodes (PN), lymph node ratio (LNR), and log odds of positive lymph nodes (LODDS) in survival of patients with OSCC. METHODS: Clinicopathologic data from patients with OSCC who were treated with curative purposes by surgery and neck dissection (ND) with or without subsequent adjuvant therapies from 1991 to 2015 was retrospectively assessed. The impact of the PN, LNR, LODDS, and other variables on overall survival (OS) and disease-free survival (DFS) was analyzed in univariate and multivariate analyses. RESULTS: One hundred nineteen patients were included in this study. In the univariate analysis the PN had a significant impact on OS (p = 0.001) and DFS (p = 0.020), and the LNR had a significant impact on the OS (p = 0.042). In the multivariate analysis with other relevant clinicopathologic variables, the PN was the only significantly independent factor influencing in the OS (p = 0.017) but not in DFS (p = 0.096). CONCLUSIONS: The PN is an independent prognostic indicator for OS and DFS in patients with OSCC and has the potential to aggregate the current AJCC classification. The LNR has potential to be an important prognostic indicator, but the methods for this classification require lapidation. The LODDS did not demonstrate prognostic potential.


Subject(s)
Carcinoma, Squamous Cell , Head and Neck Neoplasms , Mouth Neoplasms , Humans , Carcinoma, Squamous Cell/diagnosis , Carcinoma, Squamous Cell/surgery , Lymph Nodes/surgery , Lymph Nodes/pathology , Squamous Cell Carcinoma of Head and Neck , Neoplasm Staging , Lymphatic Metastasis/diagnosis , Lymphatic Metastasis/pathology , Retrospective Studies , Mouth Neoplasms/diagnosis , Mouth Neoplasms/surgery
4.
J Stomatol Oral Maxillofac Surg ; 123(6): e814-e821, 2022 11.
Article in English | MEDLINE | ID: mdl-35998818

ABSTRACT

BACKGROUND: To analyze the influence of the lymph node ratio (LNR) in survival of patients with OSCC METHODS: Clinicopathologic data from patients with OSCC who were treated with curative surgery and neck dissection (ND) with or without adjuvant therapies from 1991 to 2015 was retrospectively assessed. The impact of LNR and other variables on overall survival (OS) and disease-free survival (DFS) was analyzed in univariate and multivariate analyses. RESULTS: One hundred nineteen patients were included. In the univariate analysis the LNR had a significant impact on OS (p = 0.01) and DFS (p = 0.01). In the multivariate analysis, the LNR was the only significantly independent factor influencing in the OS (p = 0.03). The adjuvant therapies did not influence on the OS (p = 0.42) and DFS (p = 0.10). CONCLUSIONS: The LNR is an independent prognostic factor in patients with OSCC. The LNR alone is not recommended to indicate the performance of adjuvant therapies.


Subject(s)
Carcinoma, Squamous Cell , Head and Neck Neoplasms , Mouth Neoplasms , Humans , Mouth Neoplasms/diagnosis , Mouth Neoplasms/surgery , Carcinoma, Squamous Cell/diagnosis , Carcinoma, Squamous Cell/surgery , Lymph Node Ratio , Squamous Cell Carcinoma of Head and Neck , Prognosis , Retrospective Studies , Lymphatic Metastasis/diagnosis , Lymphatic Metastasis/pathology , Lymph Nodes/surgery , Lymph Nodes/pathology , Neoplasm Staging
6.
Oral Oncol ; 122: 105552, 2021 11.
Article in English | MEDLINE | ID: mdl-34610523

ABSTRACT

Blastoid variant of mantle cell lymphoma (MCL) is an aggressive and extremely rare malignancy. MCL may be diagnosed in lymph nodes and/or extranodal sites exhibiting a poor prognosis. MCL with primary presentation in palatine tonsils has been rarely reported. Herein, we report the case of a 73-year-old man with a painless nodular mass on the right palatine tonsil. A biopsy was performed, and microscopic analysis revealed a neoplasm composed of small to medium sized lymphocytes with finely dispersed chromatin, roundish nucleus and many mitoses. The tumor cells were positive for CD20 (L26), CD5 (4C7), Cyclin D1 (EP12), Bcl2 (124) and Ki-67 (MIB-1; 90%), and negative for Bcl6 (PG-B6p), MUM1 (MUM1p) and CD3 (Polyclonal). These findings led to the diagnosis of blastoid variant of MCL. Diagnostic workup with computed tomography scan excluded other sites of disease. The patient was treated successfully with cyclophosphamide, doxorubicin, vincristine and prednisolone (mini-CHOP regimen). Although the blastoid variant of MCL is rare, it should be included in the differential diagnosis of rapid-growing masses in the palatine tonsil.


Subject(s)
Lymphoma, Mantle-Cell , Palatine Tonsil , Aged , Humans , Lymph Nodes , Lymphoma, Mantle-Cell/diagnosis , Lymphoma, Mantle-Cell/drug therapy , Male , Palatine Tonsil/pathology
8.
Araçatuba; s.n; 2020. 42 p. ilus, tab.
Thesis in English | LILACS, BBO - Dentistry | ID: biblio-1434689

ABSTRACT

Objetivo: Avaliar a infiltraçãdo dos linfócitos CD4+ , CD8 + e FOXP3+ e sua correlação com caracteristicas sociodemográfica, clinicopatologicas e estilo de vida de pacientes com leucoplasias bucais. Pacientes e métodos: Oitenta pacientes com diagnóstico de leucoplasia bucal foram incluidos no estudo. Análises retrospectivas foram realizadas para verificar as características sociodemográficos, clinicopatológicos e estilo de vida dos pacientes. O infiltrado linfocitário foi caracterizado por imunoistoquímica com antígenos contra de CD4+ , CD8 + e FOXP3+ . Resultados: Dos 80 pacientes incluidos neste estudo, (60%) eram homens e a idade variou de 25 a 82 anos com idade média de 58,6 anos.Trinta e oito (47.5%) eram idosos, Trinta e dois (40%) eram adultos de meia idade e apenas dez (10%) adultos jovens. Sessenta e um dos pacientes eram fumantes (76.2%) e quarenta e seis eram etilistas (57.5%). Vinte e sete (35.5%) das lesões apresentaram algum grau de displasia epitelial. O grau de displasia epitelial apresentou correlação positiva com a intensidade do consumo do alcool (p=0.008). Houve correlação positiva entre os linfócitos CD4+ e CD8+ (p=0.005). Conclusão: O infiltrado linfocitário não foi relacionado com nenhuma característica clinicopatológica das lecoplasias bucais. Entretanto, o grau de displasia está relacionado ao estilo de vida dos pacientes(AU)


Objective: To evaluate the infiltration of CD4+ , CD8+ and FOXP3+ lymphocytes and their correlation with sociodemographic, clinicopathological and lifestyle characteristics of patients with oral leukoplakia. Patients and methods: Eighty patients diagnosed with oral leukoplakia were included in the study. Retrospective analyses were performed in order to verify the sociodemographic, clinicopathologic and lifestyle characteristics. The lymphocytic infiltrate characterization was performed by immunohistochemistry with antibodies against CD4+, CD8+, and FOXP3+ markers. Results: Of 80 patients included in the study, 60% were men, and their age ranged from 25 to 82 years, with a mean of 58.6. Thirty-eight patients (47.5%) were elderly, Thirty-two (40%) middle-aged, and only ten (10%) young adults. Sixty-one of the patients were smokers (76.2%) and forty-six were alcoholics (57.5%). Twenty-seven (35.5%) of the lesions presented some degree of dysplasia. The degree of epithelial dysplasia was correlated with the intensity of alcohol consumption (p=0.008). A positive correlation was found between CD4+ and CD8+ lymphocytes (p=0.005). Conclusion: The lymphocytic infiltrate of oral leukoplakia was not correlated with any clinicopathologic characteristic. However, the degree of epithelial dysplasia was correlated with the lifestyle of the patients(AU)


Subject(s)
Humans , Male , Female , Adult , Middle Aged , Aged , Aged, 80 and over , Leukoplakia, Oral , T-Lymphocytes , Alcohol Drinking , Immunohistochemistry , CD4 Antigens , CD8 Antigens , Smokers , Antigens
9.
Head Neck ; 41(12): 4209-4228, 2019 12.
Article in English | MEDLINE | ID: mdl-31502752

ABSTRACT

BACKGROUND: We investigated the efficacy of hyperbaric oxygen (HBO), low-intensity laser (LIL), and platelet-rich plasma (PRP) in the management of medication-related osteonecrosis of the jaws (MRONJ). METHODS: A literature search was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. Two examiners independently assessed eligibility and risk of bias and extracted data. RESULTS: There was improvement in 75.6% of the 41 patients submitted to HBO, with positive effects on pain relief and decreased size and number of lesions at a faster rate, with better effects when the drug was discontinued. For LIL, 158 (64.2%) of the 246 patients/sites improved the symptoms and 98 (39.8%) healed completely. Fourteen (17.3%) of the 81 patients treated with PRP significantly improved the symptoms and 65 (80.2%) completely healed. CONCLUSIONS: These therapies served as safe and effective adjuvant modalities for MRONJ treatment. The lack of randomized clinical trials evidences the need for more high-quality investigations on the subject.


Subject(s)
Bisphosphonate-Associated Osteonecrosis of the Jaw/therapy , Hyperbaric Oxygenation/methods , Laser Therapy/methods , Platelet-Rich Plasma , Aged , Aged, 80 and over , Bisphosphonate-Associated Osteonecrosis of the Jaw/pathology , Bone Density Conservation Agents/adverse effects , Combined Modality Therapy , Denosumab/adverse effects , Diphosphonates/adverse effects , Female , Humans , Jaw Diseases/chemically induced , Jaw Diseases/therapy , Male , Middle Aged , Osteonecrosis/chemically induced , Osteonecrosis/therapy , Pain Management , Pamidronate/adverse effects , Randomized Controlled Trials as Topic
11.
RFO UPF ; 22(2): 203-206, 08/01/2018.
Article in Portuguese | LILACS | ID: biblio-877831

ABSTRACT

Objetivo: o objetivo do presente trabalho é relatar dois casos clínicos de pacientes com displasia cemento-óssea florida (DCOF) com características distintas no exame de tomografia computadorizada de feixe cônico (TCFC). Relato de caso: no primeiro caso, paciente do gênero feminino, melanoderma, 49 anos de idade com lesões hipodensas assintomáticas distribuídas por toda a mandíbula, sugestivas de DCOF em estágio imaturo. No segundo caso, uma paciente do gênero feminino, melanoderma de 48 anos de idade, as lesões apresentavam-se hiperdensas com halo hipodenso, em mandíbula localizada bilateralmente, assintomáticas, caracterizando o estágio maduro da DCOF. Em ambos os casos, o diagnóstico de DCOF foi estabelecido por meio das imagens de TCFC associadas às características clínicas das pacientes. Nenhum tratamento foi instituído, apenas o controle periódico. Considerações finais: os casos clínicos apresentados ressaltam a importância da TCFC no diagnóstico das lesões fibro-ósseas, que, como ilustrado, podem apresentar características imaginológicas bastante distintas. Por possuir um amplo espectro de apresentações e ser encontrada em exames de imagens realizados para outros fins, a DCOF pode levar o cirurgião dentista à tomada de decisões precipitadas e, muitas vezes, condutas inadequadas, visto que procedimentos cirúrgicos são contraindicados nesses casos.

12.
Cancer Lett ; 414: 116-126, 2018 02 01.
Article in English | MEDLINE | ID: mdl-29129782

ABSTRACT

Green tea (GT) has been consumed as a beverage for thousands of years because of its therapeutic properties observed over time. Because there is no sufficient evidence supporting the protective role of tea intake during the development of acute myeloid leukaemia, we herein study GT extract effects on an acute promyelocytic leukaemia model. Our results demonstrated that GT reduces leucocytosis and immature cells (blasts) in peripheral blood, bone marrow (BM), and spleen of leukaemic mice, parallel with an increase of mature cells in the BM. In addition, GT induces apoptosis of cells in the BM and spleen, confirmed by activation of caspase-3, -8 and -9; GT reduces the malignant clones CD34+ and CD117+ in the BM and reduces CD117+ and Gr1+ immature myeloid cells in the spleen; GT increases intracellular reactive oxygen species (ROS) in the BM Gr1+ cells while reducing CD34+ and CD117+ cells; GT reduces CXCR4 expression on CD34+ and CD117+ cells, and reduces the nuclear translocation of HIF-1α. GT has anti-proliferative effects in leukaemia in vivo by inhibiting malignant clone expansion, probably by modulating the intracellular production of ROS.


Subject(s)
Leukemia, Promyelocytic, Acute/drug therapy , Plant Extracts/pharmacology , Reactive Oxygen Species/metabolism , Tea/chemistry , Animals , Apoptosis/drug effects , Bone Marrow Cells/drug effects , Bone Marrow Cells/metabolism , Caspases/metabolism , Disease Models, Animal , Humans , Leukemia, Promyelocytic, Acute/blood , Leukemia, Promyelocytic, Acute/pathology , Mice, Inbred NOD , Mice, SCID , Phytotherapy , Receptors, CXCR4/metabolism , Spleen/drug effects , Spleen/metabolism , Spleen/pathology
13.
Ecology ; 95(8): 2192-201, 2014 Aug.
Article in English | MEDLINE | ID: mdl-25230470

ABSTRACT

What determines the seasonal and interannual variation of growth rates in trees in a tropical forest? We explore this question with a novel four-year high-temporal-resolution data set of carbon allocation from two forest plots in the Bolivian Amazon. The forests show strong seasonal variation in tree wood growth rates, which are largely explained by shifts in carbon allocation, and not by shifts in total productivity. At the deeper soil plot, there was a clear seasonal trade-off between wood and canopy NPP, while the shallower soils plot showed a contrasting seasonal trade-off between wood and fine roots. Although a strong 2010 drought reduced photosynthesis, NPP remained constant and increased in the six-month period following the drought, which indicates usage of significant nonstructural carbohydrate stores. Following the drought, carbon allocation increased initially towards the canopy, and then in the following year, allocation increased towards fine-root production. Had we only measured woody growth at these sites and inferred total NPP, we would have misinterpreted both the seasonal and interannual responses. In many tropical forest ecosystems, we propose that changing tree growth rates are more likely to reflect shifts in allocation rather than changes in overall productivity. Only a whole NPP allocation perspective can correctly interpret the relationship between changes in growth and changes in productivity.


Subject(s)
Droughts , Ecosystem , Seasons , Trees , Tropical Climate , Animals , Bolivia , Environmental Monitoring , Models, Biological , Rain , Time Factors
14.
Histochem Cell Biol ; 139(2): 233-47, 2013 Feb.
Article in English | MEDLINE | ID: mdl-22990596

ABSTRACT

Isoform 1 of the sodium-vitamin C co-transporter (SVCT1) is expressed in the apical membrane of proximal tubule epithelial cells in adult human and mouse kidneys. This study is aimed at analyzing the expression and function of SVCTs during kidney development. RT-PCR and immunohistochemical analyses revealed that SVCT1 expression is increased progressively during postnatal kidney development. However, SVCT1 transcripts were barely detected, if not absent, in the embryonic kidney. Instead, the high-affinity transporter, isoform 2 (SVCT2), was strongly expressed in the developing kidney from E15; its expression decreased at postnatal stages. Immunohistochemical analyses showed a dynamic distribution of SVCT2 in epithelial cells during kidney development. In renal cortex tubular epithelial cells, intracellular distribution of SVCT2 was observed at E19 with distribution in the basolateral membrane at P1. In contrast, SVCT2 was localized to the apical and basolateral membranes between E17 and E19 in medullary kidney tubular cells but was distributed intracellularly at P1. In agreement with these findings, functional expression of SVCT2, but not SVCT1 was detected in human embryonic kidney-derived (HEK293) cells. In addition, kinetic analysis suggested that an ascorbate-dependent mechanism accounts for targeted SVCT2 expression in the developing kidney during medullary epithelial cell differentiation. However, during cortical tubular differentiation, SVCT1 was induced and localized to the apical membrane of tubular epithelial cells. SVCT2 showed a basolateral polarization only for the first days of postnatal life. These studies suggest that the uptake of vitamin C mediated by different SVCTs plays differential roles during the ontogeny of kidney tubular epithelial cells.


Subject(s)
Kidney/growth & development , Kidney/metabolism , Sodium-Coupled Vitamin C Transporters/metabolism , Animals , Ascorbic Acid/metabolism , Cell Membrane/chemistry , Cell Membrane/metabolism , Cells, Cultured , HEK293 Cells , Humans , Kidney/embryology , Kinetics , Male , Mice , Mice, Inbred C57BL , RNA, Messenger/genetics , RNA, Messenger/metabolism , Sodium-Coupled Vitamin C Transporters/analysis , Sodium-Coupled Vitamin C Transporters/genetics
15.
Kidney Int ; 74(10): 1278-86, 2008 Nov.
Article in English | MEDLINE | ID: mdl-18614995

ABSTRACT

Vitamin C is reabsorbed from the renal lumen by one isoform of sodium-vitamin C co-transporters that mediate high affinity sodium-dependent L-ascorbic acid transport. Sodium-vitamin C cotransporter-1 mRNA has been detected in intestine and liver and the S3 segment of the renal proximal tubule. Here, we found that its distribution was broader and all three proximal tubule segments of mouse and human expressed the transporter but the S3 segment had the highest expression. Sodium-vitamin C co-transporter-1 expression was also found in the renal epithelial-derived LLC-PK1 cell line. Ascorbic acid transport in these cells was regulated by a single kinetic component that depended on the sodium concentration, pH and temperature. Reducing ascorbate concentration increased the apical expression of the transporter suggesting the presence of a feedback system for regulation of transporter abundance at the luminal membrane.


Subject(s)
Ascorbic Acid/metabolism , Sodium/metabolism , Symporters/metabolism , Absorption , Animals , Humans , Hydrogen-Ion Concentration , Intestines/chemistry , Kidney Tubules, Proximal/chemistry , Kinetics , Liver/chemistry , Mice , RNA, Messenger/analysis , Temperature
16.
J Cell Physiol ; 207(3): 614-27, 2006 Jun.
Article in English | MEDLINE | ID: mdl-16523487

ABSTRACT

It has been proposed that the enhanced metabolic activity of tumor cells is accompanied by an increased expression of facilitative hexose transporters (GLUTs). However, a previous immunohistochemical analysis of GLUT1 expression in 154 malignant human neoplasms failed to detect the GLUT1 isoform in 87 tumors. We used 146 normal human tissues and 215 tumor samples to reassess GLUT1 expression. A similar number of samples were used to compare the expression of GLUT2-6 and 9. The classical expression of GLUT1-5 in different normal human tissues was confirmed, however, we were unable to detect GLUT2 in human pancreatic islet cells. GLUT6 was principally detected in testis germinal cells and GLUT9 was localized in kidney, liver, heart, and adrenal. In tumor samples, GLUT1, 2, and 5 were the main transporters detected. GLUT1 was the most widely expressed transporter, however, 42% of the samples had very low-to-negative expression levels. GLUT2 was detected in 31% of the samples, being mainly expressed in breast, colon, and liver carcinoma. GLUT5 was detected in 27% of breast and colon adenocarcinoma, liver carcinoma, lymphomas, and testis seminoma samples. In situ RT-PCR and ultrastructural immunohistochemistry confirmed GLUT5 expression in breast cancer. GLUT6 and 9 are not clearly over-expressed in human cancer. The extensive expression of GLUT2 and 5 (glucose/fructose and fructose transporters, respectively) in malignant human tissues indicates that fructose may be a good energy substrate in tumor cells. Our functional data obtained in vitro in different tumor cells support this hypothesis. Additionally, these results suggest that fructose uptake could be used for positron emission tomography imaging and, may possibly represent a novel target for the development of therapeutic agents in different human cancers.


Subject(s)
Breast/metabolism , Breast/pathology , Glucose Transport Proteins, Facilitative/metabolism , Neoplasms/metabolism , Neoplasms/pathology , Animals , Biopsy , Breast/ultrastructure , Gene Expression Regulation, Neoplastic , Glucose Transport Proteins, Facilitative/genetics , Health , Humans , Immunohistochemistry , In Situ Hybridization , Mice , Microscopy, Immunoelectron , Neoplasms/genetics , Neoplasms/ultrastructure , Organ Specificity , Rats , Tumor Cells, Cultured
17.
J Neurochem ; 86(3): 709-24, 2003 Aug.
Article in English | MEDLINE | ID: mdl-12859684

ABSTRACT

The GLUT2 glucose transporter and the K-ATP-sensitive potassium channels have been implicated as an integral part of the glucose-sensing mechanism in the pancreatic islet beta cells. The expression of GLUT2 and K-ATP channels in the hypothalamic region suggest that they are also involved in a sensing mechanism in this area. The hypothalamic glial cells, known as tanycytes alpha and beta, are specialized ependymal cells that bridge the cerebrospinal fluid and the portal blood of the median eminence. We used immunocytochemistry, in situ hybridization and transport analyses to demonstrate the glucose transporters expressed in tanycytes. Confocal microscopy using specific antibodies against GLUT1 and GLUT2 indicated that both transporters are expressed in alpha and beta tanycytes. In addition, primary cultures of mouse hypothalamic tanycytes were found to express both GLUT1 and GLUT2 transporters. Transport studies, including 2-deoxy-glucose and fructose uptake in the presence or absence of inhibitors, indicated that these transporters are functional in cultured tanycytes. Finally, our analyses indicated that tanycytes express the K-ATP channel subunit Kir6.1 in vitro. As the expression of GLUT2 and K-ATP channel is linked to glucose-sensing mechanisms in pancreatic beta cells, we postulate that tanycytes may be responsible, at least in part, for a mechanism that allows the hypothalamus to detect changes in glucose concentrations.


Subject(s)
Ependyma/metabolism , Glucose/metabolism , Hypothalamus/metabolism , Monosaccharide Transport Proteins/metabolism , Neuroglia/metabolism , Animals , Cells, Cultured , Ependyma/cytology , Glucose Transporter Type 1 , Glucose Transporter Type 2 , Hypothalamus/cytology , Immunohistochemistry , In Situ Hybridization , Mice , Mice, Inbred C57BL , Neuroglia/cytology , Potassium Channels, Inwardly Rectifying/biosynthesis
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