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1.
Kardiochir Torakochirurgia Pol ; 19(1): 61-62, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35414820
2.
Materials (Basel) ; 14(18)2021 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-34576681

RESUMO

The lungs are a common site of metastases from malignant tumors. Their removal with a minimal but safe tissue margin is essential for the long-term survival of patients. The aim of this study was to evaluate the usefulness of a 1940 nm thulium-doped fiber laser (TDFL) and a 1470 nm diode laser (DL) in a pig model of lung surgery that involved the incision and excision of lung tissue. Histopathological analysis was performed on days 0 and 7 after surgery. Neither TDFL nor DL caused significant perioperative or postoperative bleeding. Histological analysis revealed the presence of carbonized necrotic tissue, mixed fibrin-cellular exudate in the superficial zone of thermal damage and bands of deeper thermal changes. The mean total width of thermal damage on day 0 was 499.46 ± 61.44 and 937.39 ± 109.65 µm for TDFL and DL, respectively. On day 7, cell activation and repair processes were visible. The total width of thermal damage was 2615.74 ± 487.17 µm for TDFL vs. 6500.34 ±1118.02 µm for DL. The superficial zone of thermal damage was narrower for TDFL on both days 0 and 7. The results confirm the effectiveness of both types of laser in cutting and providing hemostasis in the lungs. TDFL caused less thermal damage to the lung parenchyma than DL.

3.
Int J Nanomedicine ; 16: 6049-6065, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34511905

RESUMO

PURPOSE: Healing of osteoporotic defects is challenging and requires innovative approaches to elicit molecular mechanisms promoting osteoblasts-osteoclasts coupling and bone homeostasis. METHODS: Cytocompatibility and biocompatibility of previously characterised nanocomposites, i.e Ca5(PO4)3OH/Fe3O4 (later called nHAp/IO) functionalised with microRNAs (nHAp/IO@miR-21/124) was tested. In vitro studies were performed using a direct co-culture system of MC3T3-E1 pre-osteoblast and 4B12 pre-osteoclasts. The analysis included determination of nanocomposite influence on cultures morphology (confocal imaging), viability and metabolic activity (Alamar Blue assay). Pro-osteogenic signals were identified at mRNA, miRNA and protein level with RT-qPCR, Western blotting and immunocytochemistry. Biocompatibility of biomaterials was tested using bilateral cranial defect performed on a senescence-accelerated mouse model, ie SAM/P6 and Balb/c. The effect of biomaterial on the process of bone healing was monitored using microcomputed tomography. RESULTS: The nanocomposites promoted survival and metabolism of bone cells, as well as enhanced functional differentiation of pre-osteoblasts MC3T3-E1 in co-cultures with pre-osteoclasts. Differentiation of MC3T3-E1 driven by nHAp/IO@miR-21/124 nanocomposite was manifested by improved extracellular matrix differentiation and up-regulation of pro-osteogenic transcripts, ie late osteogenesis markers. The nanocomposite triggered bone healing in a cranial defect model in SAM/P6 mice and was replaced by functional bone in Balb/c mice. CONCLUSION: This study demonstrates that the novel nanocomposite nHAp/IO can serve as a platform for therapeutic miRNA delivery. Obtained nanocomposite elicit pro-osteogenic signals, decreasing osteoclasts differentiation, simultaneously improving osteoblasts metabolism and their transition toward pre-osteocytes and bone mineralisation. The proposed scaffold can be an effective interface for in situ regeneration of osteoporotic bone, especially in elderly patients.


Assuntos
MicroRNAs , Osteoporose , Idoso , Animais , Diferenciação Celular , Humanos , Nanopartículas Magnéticas de Óxido de Ferro , Camundongos , MicroRNAs/genética , Osteoblastos , Osteogênese , Osteopontina/genética , Microtomografia por Raio-X
4.
Transplant Proc ; 51(8): 2781-2786, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31439326

RESUMO

INTRODUCTION: Painful chronic pancreatitis (CP) is the main indication for analgesic pancreatectomy with simultaneous islet autotransplantation to prevent postoperative diabetes mellitus (DM). However, advanced CP may lead to insulin secretion disorders and DM. There are doubts as to whether islet autotransplantation in such cases is an appropriate procedure. The aim of this study was to analyze the results of islet autotransplantation in patients with CP with already diagnosed with DM. METHOD: Between 2008 and 2015, at the Department of General and Transplantation Surgery, patients with CP and unsatisfying pain treatment with positive fasting C-peptide ( > 0.3 ng/mL) level were qualified for simultaneous pancreatectomy and islet autotransplantation. Eight procedures were performed. In 5 cases patients had DM diagnosed prior to the procedure (DM group n = 5). Three patients without DM diagnosed prior to surgery were the control group (n = 3). RESULT: There were no cases of procedure-related deaths in either group. Pain relief without analgesics was reported by all patients. Good islet function was observed in 80% (4/5) of the DM group vs 100% (3/3) in the control group (P = ns). Brittle diabetes was diagnosed in 1 patient in the DM group as a result of islet primary non-function. CONCLUSION: Patients with CP-related severe pain and DM patients with positive C-peptides should be considered for pancreatectomy and islet autotransplantation.


Assuntos
Diabetes Mellitus Tipo 1/cirurgia , Transplante das Ilhotas Pancreáticas/métodos , Pancreatectomia , Pancreatite Crônica/cirurgia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pancreatectomia/métodos , Transplante Autólogo
5.
BMC Vet Res ; 15(1): 296, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31416466

RESUMO

BACKGROUND: Cervical vertebral stenotic myelopathy (CVSM) remains one of the most important abnormalities of the cervical spine resulting in neurological deficits in horses. The aim of the following study was to compare the results of the clinical and neurological examination, the results of myelography and the post mortem anatomical and histological appearance of the spinal cord and cervical vertebrae in a horse with CVSM. CASE PRESENTATION: The following study describes a clinical case of an eight-month-old stallion with ataxia. Plain cervical radiographs indicated narrowing of the spinal canal. Conservative therapy using NSAIDs did not result in any improvement in the gait of the horse. Due to economic constraints, surgical intervention was excluded. The owner chose to humanely euthanise the horse. Immediately after euthanasia, post mortem myelography was performed, and measurements of the myelographic dye column were taken. They revealed a 67% DMC reduction and a 64% DD reduction at the C3/C4 level. Afterwards, an anatomical dissection was performed. The cervical vertebrae and vertebral canal were macroscopically inspected and measured and indicated a 44% narrowing of the canal at the C3/C4 level. The spinal cord was removed and underwent histological evaluation after staining. Microscopic lesions were visible at the level of the compression and included axonal degeneration with partial or complete loss of myelin in the white matter of the lateral and dorsal funiculi as well as the formation of dysfunctional so-called "spongy structures". An increase in the number of microglial cells and collagen was also observed. The formation of glial scars was excluded. Immunohistochemical studies revealed a negative transmembrane glycoprotein CD68(-) - monocyte response and a negative tumor necrosis alpha TNFα (-) reaction. CONCLUSIONS: CVSM may be difficult to diagnose, even for experienced veterinary surgeons. Currently, an ex vivo histopathologic examination of the spinal cord is thought to be the gold standard in the diagnosis of CVSM. Our histological examination revealed no CVSM-specific glial scar formation and a CD68(-) negative and TNF-α negative reaction, which have not been previously reported. Histological lesions in CVSM may vary depending show inter-individual variability and on the treatment, which further hinders ex-vivo diagnostics.


Assuntos
Vértebras Cervicais/patologia , Doenças dos Cavalos/diagnóstico por imagem , Compressão da Medula Espinal/veterinária , Doenças da Medula Espinal/veterinária , Estenose Espinal/veterinária , Animais , Ataxia/etiologia , Ataxia/patologia , Ataxia/veterinária , Doenças dos Cavalos/patologia , Cavalos , Masculino , Medula Espinal/patologia , Compressão da Medula Espinal/patologia , Doenças da Medula Espinal/patologia , Estenose Espinal/patologia , Estenose Espinal/cirurgia
6.
Wideochir Inne Tech Maloinwazyjne ; 14(2): 249-254, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31118991

RESUMO

INTRODUCTION: Increased values of emerging fat indices are correlated with increased cardiovascular risk. AIM: To examine the novel non-invasive predictors of coronary disease, namely the carotid extra-media thickness (EMT), PATIMA, and epicardial adipose tissue (EAT), in a group of patients with morbid obesity. MATERIAL AND METHODS: We examined a group of 40 morbidly obese (OB) patients and a control group (CG). All patients were subjected to anthropometric measurements, as well as laboratory and ultrasound examinations. RESULTS: EATmean and EMTmean differed significantly between groups (OB vs. CG): 5.09 vs. 3.50 and 808.50 vs. 737.00, p < 0.0001, respectively. CONCLUSIONS: Strong correlations were found between novel non-invasive predictors of coronary disease, namely the carotid extra-media thickness, PATIMA, and epicardial adipose tissue. The above-mentioned fat indices were not found to correlate significantly with BMI or other body weight-related parameters used to assess the adipose tissue content. Further studies are required.

7.
Ther Clin Risk Manag ; 14: 2221-2228, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30519030

RESUMO

BACKGROUND: Wells and Geneva scores are widely used in the assessment of pretest probability of pulmonary embolism (PE). OBJECTIVE: The objective of this study was to examine the hypothesis that mean platelet volume (MPV) may better predict PE than the clinical prediction rules. METHODS: A study was performed among patients with PE. Baseline characteristics and complete blood counts including MPV were prospectively recorded upon admission. To assess clinical probability in patients with PE risk, we used Wells and Geneva scores. RESULTS: Data records of 136 patients (males: 44%) with median age of 66 years (interquartile range [IQR] 57.5-78.0) diagnosed with PE at the Intensive Cardiac Therapy Clinic in Lodz (Poland) were analyzed. Baseline characteristics indicate that patients suffered from arterial hypertension (65%), obesity (32%), and diabetes mellitus (24%). Furthermore, they reported active smoking (21%), prolonged immobilization (20%), major surgery (21%), pregnancy (4%), and oral contraceptives (9%). Patients presented with various symptoms. The MPV, plateletcrit, and D-dimer values on admission were respectively as follows: 10.71 (IQR 3.29-13.67), 0.2 (IQR 0.15-0.24), and 9.23 (IQR 8.5-9.85). The study revealed that Wells score correlated significantly with an elevated MPV value (P<0.05) per contra to Geneva score (P>0.05). According to our results, there is a lack of coherence between Wells and Geneva scores (P>0.05). Finally, we determined that the optimum MPV level cutoff point for PE on admission with reference to the original Wells score is 9.6 fL. CONCLUSION: MPV may be considered useful as an adjunctive or independent predictive marker for PE used in lieu of clinical prediction rules.

8.
J Biomed Sci ; 24(1): 83, 2017 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-29084538

RESUMO

BACKGROUND: Cells adapt to hypoxia by transcriptional induction of genes that participate in regulation of angiogenesis, glucose metabolism and cell proliferation. The primary factors mediating cell response to low oxygen tension are hypoxia inducible factors (HIFs), oxygen-dependent transcription activators. The stability and activity of the α subunits of HIFs are controlled by hydroxylation reactions that require ascorbate as a cofactor. Therefore, deficiency of intracellular vitamin C could contribute to HIFs overactivation. In this study, we investigated whether vitamin C content of human thyroid lesions is associated with HIF-1α and HIF-2α protein levels. METHODS: Expression of HIF-1α and HIF-2α as well as vitamin C content was analyzed in thyroid lesions and cultured thyroid carcinoma cell lines (FTC-133 and 8305c) treated with hypoxia-mimetic agent (cobalt chloride) and ascorbic acid. The expression of HIFs and hypoxia-induced glucose transporters were determined by Western blots while quantitative real-time PCR (qRT-PCR) was performed to detect HIFs mRNA levels. Ascorbate and dehydroascorbate levels were measured by HPLC method. RESULTS: We found an inverse correlation between vitamin C level and HIF-1α but not HIF-2α expression in thyroid lesions. These results agree with our in vitro study showing that vitamin C induced a dose - dependent decrease of HIF-1α but not HIF-2α protein level in thyroid cancer cells FTC-133 and 8305C. The decreased HIF-1α expression was correlated with reduced expression of hypoxia-related glucose transporter 1 (GLUT1) in thyroid cancer cells. CONCLUSION: The results demonstrate that HIF-1α activation is associated with vitamin C content in thyroid lesions. Our study suggests that high tumor tissue ascorbate level could limit the expression of HIF-1α and its targets in thyroid lesions.


Assuntos
Deficiência de Ácido Ascórbico/complicações , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Ácido Desidroascórbico/deficiência , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Neoplasias da Glândula Tireoide/fisiopatologia , Vitaminas/metabolismo , Adulto , Idoso , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Linhagem Celular Tumoral , Feminino , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Masculino , Pessoa de Meia-Idade , Polônia , Glândula Tireoide/fisiopatologia , Neoplasias da Glândula Tireoide/etiologia
10.
11.
Kardiochir Torakochirurgia Pol ; 13(2): 189-91, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27516801

RESUMO

The first open-heart surgery in Gdansk took place in 1975. It was possible thanks to the gift of a Pemco extracorporeal circulation machine from the Netherlands to the Surgery Institute of the Medical Academy of Gdansk. The article presents additional, unpublished informations which enable a new interpretation of the previously known facts.

12.
Nutr Cancer ; 67(8): 1333-41, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26381034

RESUMO

Enhanced glucose requirement of cancer cells is associated with an increased glucose transport across plasma membrane that is mediated by a family of facilitated glucose transporter proteins, named GLUTs. GLUT1 is the main transporter in thyroid cancer cells. Glucose is the principal physiological substrate of GLUT1; however, it is also capable of transporting of oxidized form of vitamin C [i.e., dehydroascorbic acid (DHAA) which inside the cells is reduced to ascorbic acid (AA)]. The objective of this study was to determine the effect of normo-, hypo-, and hyperglycemia conditions on GLUT1-dependent intracellular ascorbate accumulation and viability of thyroid cancer cells. GLUT1 seems to be the main DHAA transporter in thyroid cancer cells because its knockdown by RNAi reduced DHAA accumulation by more than 80%. The results showed that in thyroid cancer cells high glucose inhibits both transport of AA and DHAA. Inhibition of vitamin C transport by glucose had a cytotoxic effect on the cells. However, stabilization of vitamin C in one of 2 forms (i.e., AA or DHAA) abolished this effect. These results suggest that cytotoxic effect is rather associated with extracellular accumulation of vitamin C and changes of its oxidation state than with intracellular level of ascorbate.


Assuntos
Ácido Ascórbico/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Transportador de Glucose Tipo 1/fisiologia , Glucose/farmacologia , Neoplasias da Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/patologia , Ácido Ascórbico/farmacologia , Transporte Biológico/efeitos dos fármacos , Linhagem Celular Tumoral , Ácido Desidroascórbico/farmacologia , Regulação para Baixo , Expressão Gênica/efeitos dos fármacos , Transportador de Glucose Tipo 1/genética , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética
13.
Oncol Rep ; 33(2): 913-20, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25502934

RESUMO

Cancer cells exhibit an altered metabolism characterized by enhanced glycolysis and glucose consumption. In glucose­addicted cancer cells upregulation of glucose transport across the plasma membrane is mediated by a family of facilitated glucose transporter proteins, particularly glucose transporter 1 (GLUT1). The aim of the present study was to investigate the impact of GLUT1 expression on glucose uptake and viability of FTC-133 and 8305c thyroid cancer cells growing in hypoglycemic, normoglycemic and hyperglycemic conditions. The results showed that the total expression of GLUT1 was higher in the two cell types growing in low glucose compared to cells growing in normoglycemia or hyperglycemia and this was correlated with AKT Ser473 phosphorylation but not with the expression of hypoxia inducible factor α (HIF1α). However, the membrane expression of GLUT1 was correlated with HIF1α expression. HIF1α expression was positively correlated with the glucose concentration in FTC-133 cells, whereas this expression was inversely correlated in 8305c cells. Glucose uptake was dependent on the membrane level of GLUT1 but not total GLUT1 expression. Downregulation of GLUT1 expression by RNAi in FTC-133 cells caused a reduction in glucose uptake but did not significantly affect cell viability. In the case of 8305c cells showing low endogenous GLUT1 expression and lack of HIF1α expression in normoxic conditions GLUT1 RNAi impacted cell viability. These data suggested that GLUT1 may be part of an AKT1-dependent mechanism allowing cells to survive in low levels of glucose. Glucose concentration inversely affected HIF1α expression and the level of GLUT1 in membrane as well as glucose uptake in FTC-133 and 8305c cells. The extent of GLUT1 impact on cell viability was also cell-type-dependent.


Assuntos
Regulação Neoplásica da Expressão Gênica , Transportador de Glucose Tipo 1/metabolismo , Glucose/química , Neoplasias da Glândula Tireoide/metabolismo , 4-Cloro-7-nitrobenzofurazano/análogos & derivados , 4-Cloro-7-nitrobenzofurazano/química , Linhagem Celular Tumoral , Membrana Celular/metabolismo , Sobrevivência Celular , Desoxiglucose/análogos & derivados , Desoxiglucose/química , Inativação Gênica , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo
14.
Mol Med Rep ; 6(3): 601-6, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22752218

RESUMO

The enhancement of glucose metabolism in neoplastic cells is mediated by the overexpression of key glycolytic enzymes and glucose transporters (GLUTs). In particular, an increased expression of hypoxia-related GLUT1 and GLUT3 has been found in a variety of malignancies. The aim of this study was to examine the expression levels of GLUT1 and GLUT3 in benign and malignant thyroid tumors, as well as in non-neoplastic lesions. Analysis of the mRNA expression levels of solute carrier family 2, member 1 (SLC2A1) and solute carrier family 2, member 3 (SLC2A3) (genes coding GLUT1 and GLUT3, respectively) was performed by the real-time PCR method with fluorescent probes. GLUT1 and GLUT3 protein expression levels were determined in thyroid specimens by immunodetection after separation of proteins on 10% polyacrylamide slab gels and electrotransfer onto Immobilon-P membranes. The majority of papillary carcinoma samples showed a higher expression of GLUT1 and GLUT3 in comparison with follicular carcinoma cases and non-neoplastic thyroid lesions. A tendency towards an increased expression of GLUT1 and GLUT3 was observed in papillary carcinoma cases with more advanced disease stages. Moreover, a significant correlation was noted between the hypoxia-related GLUT1 and GLUT3 expression determined by both methods. In conclusion, our findings suggest that GLUT1 and GLUT3 play an important role in the pathology of thyroid glands.


Assuntos
Transportador de Glucose Tipo 1/metabolismo , Transportador de Glucose Tipo 3/metabolismo , Hipóxia , Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Papilar/metabolismo , Carcinoma Papilar/patologia , Feminino , Corantes Fluorescentes/química , Transportador de Glucose Tipo 1/genética , Transportador de Glucose Tipo 3/genética , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/patologia
15.
Postepy Hig Med Dosw (Online) ; 66: 165-74, 2012 Jan 04.
Artigo em Polonês | MEDLINE | ID: mdl-22470192

RESUMO

Malignant cells are known to enhance glucose metabolism, to increase glucose uptake and to inhibit the process of oxidative phosphorylation. Accelerated glycolysis is one of the biochemical characteristics of cancer cells that allow them to compensate the inefficient extraction of energy from glucose in order to continue their uncontrolled growth and proliferation. Upregulation of glucose transport across the plasma membrane is mediated by a family of facilitated glucose transporter proteins named GLUT. Overexpression of GLUTs, especially the hypoxia-responsive GLUT1, has been frequently observed in various human carcinomas. Many studies have reported a correlation between GLUT1 expression level and the grade of tumor aggressiveness, which suggests that GLUT1 expression may be of prognostic significance. Therefore, GLUT1 is a key rate-limiting factor in the transport and glucose metabolism in cancer cells. This paper presents the current state of knowledge on GLUT1 regulation as well as its utility in the diagnosis and therapy of cancers.


Assuntos
Biomarcadores Tumorais/metabolismo , Transportador de Glucose Tipo 1/antagonistas & inibidores , Transportador de Glucose Tipo 1/metabolismo , Neoplasias/diagnóstico , Neoplasias/metabolismo , Transporte Biológico , Expressão Gênica , Proteínas Facilitadoras de Transporte de Glucose/metabolismo , Transportador de Glucose Tipo 1/química , Transportador de Glucose Tipo 1/genética , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Estrutura Molecular , Gradação de Tumores , Neoplasias/patologia , Neoplasias/terapia , Oncogenes/genética , Fosforilação Oxidativa , Prognóstico , Serina-Treonina Quinases TOR/metabolismo , Regulação para Cima
16.
Comp Biochem Physiol B Biochem Mol Biol ; 162(1-3): 51-5, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22495200

RESUMO

The activity of fructose-1,6-bisphosphatase (FBPase; EC 3.1.3.11) isozymes is influenced by AMP, Ca2+ and by reversible interactions with subcellular structures. In contrast to mammalian and avian isozymes, the kinetic properties of FBPases from ectothermal vertebrates are not fully described. To get some insight into mechanism of glycogen resynthesis in ectothermal vertebrates we examined the features of FBPases isolated from Cyprinus carpio skeletal muscle and liver. To investigate the evolutionary origin of the sensitivity of FBPase to effectors, we performed a phylogenetic analysis of known animal amino acids sequences of the enzyme. Based on our findings, we hypothesize that the high, mammalian-like, sensitivity of FBPase to Ca2+ is not essential for controlling the stability of glyconeogenic complex in striated muscles, instead it ensures the precise regulation of mitochondrial metabolism during prolonged Ca2+ elevation in contracting muscle fibers. Comparison of the kinetic properties of vertebrate and insect FBPases suggests that the high sensitivity of muscle isozyme to inhibitors has arisen as an adaptation enabling coordination of energy metabolism in warm-blooded animals.


Assuntos
Monofosfato de Adenosina/fisiologia , Cálcio/fisiologia , Carpas/metabolismo , Frutose-Bifosfatase/metabolismo , Fígado/enzimologia , Músculos/enzimologia , Monofosfato de Adenosina/farmacologia , Animais , Cálcio/farmacologia , Evolução Molecular , Cinética , Fígado/metabolismo , Músculos/metabolismo , Filogenia
17.
Endocr Pathol ; 22(4): 206-11, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21898122

RESUMO

The serine/threonine protein kinase Akt is a key molecule in the phosphatidyl inositol 3-kinase pathway that is often overactivated in human cancers. Three Akt isoforms (Akt1, Akt2, Akt3) have been identified in human cells and they show different distribution and have non-redundant functions. The aim of this study was to determine whether the expression, phosphorylation, and localization of Akt1 isoform in human thyroid malignant lesions are different from those in benign lesions. Nuclear and cytoplasmic fractions were isolated from tissue samples and Western blot method was used to detect Akt1 presence in both cellular fractions. Akt1 expression was also assessed by ELISA method. To estimate Akt1 phosphorylation, kinase was immunoprecipitated from cell lysates and tested with anti-phospho-Akt antibodies. The Akt1 expression in majority of thyroid cancer samples was significantly higher than in benign lesions (p < 0.05). Akt1 both in differentiated cancers (follicular and papillary) and benign lesions was localized mainly in cytoplasmic fraction. In two of three anaplastic cancer samples Akt1 was predominantly localized in nucleus. The ratio of phosphorylated Akt1 to total Akt1 was lower in cancers than in non-neoplastic lesions and adenomas. Thus, although Akt1 seems to be overexpressed in thyroid neoplasms, its high phosphorylation is not characteristic for thyroid cancers.


Assuntos
Carcinoma Papilar, Variante Folicular/enzimologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Neoplasias da Glândula Tireoide/enzimologia , Western Blotting , Fracionamento Celular , Citoplasma/enzimologia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Proteínas Nucleares/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-akt/biossíntese , Transdução de Sinais , Estatísticas não Paramétricas
18.
Oncol Rep ; 26(3): 743-9, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21637923

RESUMO

O-GlcNAcylation is a common and dynamic modification of intracellular proteins in which ß-N-acetyl-glucosamine moieties are attached to hydroxyl groups of serine or threonine residues (O-GlcNAc). Accumulating evidence suggests the critical role of protein O-GlcNAcylation in signal transduction, transcriptional control, cell cycle regulation and protein degradation. However, the exact role of O-GlcNAc modification in tumor pathogenesis or progression remains to be established. In the present study, we investigated the effect of increased O-GlcNAcylation of cellular proteins on IGF­1 signaling in 8305C thyroid anaplastic cancer cells. The global O-GlcNAc level in the 8305C cells was increased by down-regulation of ß-N-acetyl-D-glucosaminidase (O-GlcNAcase) activity, an enzyme which removes O-GlcNAc moieties. We demonstrated here that IGF­1 stimulates Akt1 activity in 8305C cells, and down-regulation of O-GlcNAcase activity by the chemical inhibitor PUGNAc or RNA interference method enhances this effect. Increased Akt1 activation increased cell proliferation. In cells with down-regulation of O-GlcNAcase activity, kinase GSK3ß phosphorylation and cyclin D1 levels were higher than those in control cells. Our findings suggest that increased proliferation of 8305C cells treated with PUGNAc or RNAi against O-GlcNAcase at least partially depends on the IGF­1-Akt1-GSK3ß-cyclin D1 pathway.


Assuntos
Regulação para Baixo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Neoplasias da Glândula Tireoide/metabolismo , beta-N-Acetil-Hexosaminidases/genética , Acetilglucosamina/análogos & derivados , Acetilglucosamina/farmacologia , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular , Ciclina D1/metabolismo , Quinase 3 da Glicogênio Sintase/metabolismo , Glicogênio Sintase Quinase 3 beta , Humanos , Fator de Crescimento Insulin-Like I/farmacologia , Fator de Crescimento Insulin-Like I/fisiologia , Oximas/farmacologia , Fenilcarbamatos/farmacologia , Fosforilação , Interferência de RNA , beta-N-Acetil-Hexosaminidases/antagonistas & inibidores , beta-N-Acetil-Hexosaminidases/metabolismo
19.
Int J Mol Med ; 25(4): 643-8, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20198314

RESUMO

Single N-acetylglucosamine residues attached by O-linkage to serine or threonine (O-GlcNAc) are an abundant, dynamic and inducible post-translational modification of cytoplasmic and nuclear proteins. This study analyzes the activity of the enzyme involved in the removal of these sugar residues, i.e. beta-N-acetylglucosaminidase (O-GlcNAcase) as well as the level of O-GlcNAc in benign and malignant thyroid lesions. Our results demonstrate increased activity of the enzyme in thyroid cancers in comparison to non-neoplastic lesions and adenomas. O-GlcNAc-modified proteins in thyroid cells have a predominantly nuclear distribution and are more abundant in non-neoplastic lesions than in tumors. Understanding the aberrant O-GlcNAc metabolism in thyroid cancer cells may be helpful for developing new diagnostic or treatment methods.


Assuntos
Acetilglucosaminidase/metabolismo , Núcleo Celular/enzimologia , Neoplasias da Glândula Tireoide/enzimologia , Neoplasias da Glândula Tireoide/patologia , Feminino , Humanos , Masculino , Proteínas de Neoplasias/metabolismo
20.
Tumori ; 95(3): 352-6, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19688976

RESUMO

AIMS AND BACKGROUND: The increased expression of galectin-1 on the mRNA and protein level observed in malignant thyroid tumors in comparison with benign lesions suggests that this protein may be associated with malignant transformation of thyroid epithelium. Extracellular and membrane glycoproteins are the main known ligands for this galactose-binding lectin. However, immunofluorescence studies have shown that galectin-1 is found predominantly in the intracellular compartment. The aim of this study was to examine intracellular carbohydrate ligands of galectin-1 in the thyroid, with particular attention to potential differences in their expression levels between benign and malignant lesions. METHODS: Identification of cytosolic and nuclear glycoproteins binding galectin-1 was performed by affinoblotting after separation of proteins in 8% polyacrylamide slab gels and electrotransfer onto Immobilon-P membranes. For semiquantitative analysis of glycoproteins binding galectin-1, an enzyme-linked lectino-solid-phase assay (ELLSA) was used. RESULTS: The predominant cytosolic glycoproteins binding galectin-1 had molecular masses of 50, 55, 59, 64, 85-87, 100, and 133 kDa and nuclear glycoprotein had a molecular mass of 75 kDa. There were no evident differences in glycoprotein patterns between benign and malignant thyroid lesions. The results obtained by ELLSA did not show any significant differences in lectin binding by cytosolic and nuclear proteins of thyroid lesions either. CONCLUSIONS: On the basis of these results it is tempting to suggest that interactions between galectin-1 and intracellular glycoconjugates are not critical for malignant transformation in the thyroid gland.


Assuntos
Transformação Celular Neoplásica/metabolismo , Galectina 1/metabolismo , Glicoproteínas/metabolismo , Neoplasias da Glândula Tireoide/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Técnicas Imunoenzimáticas , Masculino , Pessoa de Meia-Idade , Doenças da Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/patologia
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