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1.
J Biol Chem ; 299(5): 104678, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37028764

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is one of the most common liver diseases worldwide. Although the involvement of chronic overnutrition, systemic inflammation, and insulin resistance in the development of NAFLD is well-established, however, the associations among these remain to be elucidated. Several studies have reported that chronic overnutrition, such as excessive consumption of fats (high-fat diet, HFD), can cause insulin resistance and inflammation. However, the mechanisms by which HFD exerts inflammation and thereby promotes insulin resistance and intrahepatic fat accumulation remain poorly understood. Here, we show that HFD induces the expression of hepatic serine/threonine kinase 38 (STK38), which further induces systemic inflammation leading to insulin resistance. Notably, ectopic expression of STK38 in mouse liver leads to lean NAFLD phenotype with hepatic inflammation, insulin resistance, intrahepatic lipid accumulation, and hypertriglyceridemia in mice fed on a regular chow diet. Further, depletion of hepatic STK38 in HFD-fed mice remarkably reduces proinflammation, improves hepatic insulin sensitivity, and decreases hepatic fat accumulation. Mechanistically, two critical stimuli are elicited by STK38 action. For one stimulus, STK38 binds to Tank-Binding protein Kinase 1 and induces Tank-Binding protein Kinase 1 phosphorylation to promote NF-κß nuclear translocation that mobilizes the release of proinflammatory cytokines and eventually leads to insulin resistance. The second, stimulus involves intrahepatic lipid accumulation by enhanced de novo lipogenesis via reducing the AMPK-ACC signaling axis. These findings identify STK38 as a novel nutrient-sensitive proinflammatory and lipogenic factor in maintaining hepatic energy homeostasis, and it provides a promising target for hepatic and immune health.


Assuntos
Dieta Hiperlipídica , Hepatopatia Gordurosa não Alcoólica , Proteínas Serina-Treonina Quinases , Animais , Camundongos , Dieta Hiperlipídica/efeitos adversos , Inflamação/metabolismo , Resistência à Insulina/fisiologia , Lipídeos , Lipogênese/genética , Fígado/metabolismo , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hipernutrição , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Serina/metabolismo
2.
J Biol Chem ; 298(5): 101889, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35378127

RESUMO

An absolute or relative deficiency of pancreatic ß-cells mass and functionality is a crucial pathological feature common to type 1 diabetes mellitus and type 2 diabetes mellitus. Glucagon-like-peptide-1 receptor (GLP1R) agonists have been the focus of considerable research attention for their ability to protect ß-cell mass and augment insulin secretion with no risk of hypoglycemia. Presently commercially available GLP1R agonists are peptides that limit their use due to cost, stability, and mode of administration. To address this drawback, strategically designed distinct sets of small molecules were docked on GLP1R ectodomain and compared with previously known small molecule GLP1R agonists. One of the small molecule PK2 (6-((1-(4-nitrobenzyl)-1H-1,2,3-triazol-4-yl)methyl)-6H-indolo[2,3-b]quinoxaline) displays stable binding with GLP1R ectodomain and induces GLP1R internalization and increasing cAMP levels. PK2 also increases insulin secretion in the INS-1 cells. The oral administration of PK2 protects against diabetes induced by multiple low-dose streptozotocin administration by lowering high blood glucose levels. Similar to GLP1R peptidic agonists, treatment of PK2 induces ß-cell replication and attenuate ß-cell apoptosis in STZ-treated mice. Mechanistically, this protection was associated with decreased thioredoxin-interacting protein expression, a potent inducer of diabetic ß-cell apoptosis and dysfunction. Together, this report describes a small molecule, PK2, as an orally active nonpeptidic GLP1R agonist that has efficacy to preserve or restore functional ß-cell mass.


Assuntos
Diabetes Mellitus Tipo 2 , Desenho de Fármacos , Receptor do Peptídeo Semelhante ao Glucagon 1/antagonistas & inibidores , Células Secretoras de Insulina , Animais , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Glucagon/metabolismo , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Insulina/metabolismo , Secreção de Insulina , Células Secretoras de Insulina/metabolismo , Estreptozocina
3.
Lancet Oncol ; 21(11): e528-e537, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33152312

RESUMO

Most primary thyroid tumours are of epithelial origin. Primary thyroid mesenchymal tumours are rare but are being increasingly detected. A vast majority of thyroid mesenchymal tumours occur between the fourth and seventh decades of life, presenting as progressively enlarging thyroid nodules that often yield non-diagnostic results or spindle cells on fine needle aspiration biopsy. Surgery is the preferred mode of treatment, with adjuvant chemoradiotherapy used for malignant thyroid mesenchymal tumours. Benign thyroid mesenchymal tumours have excellent prognosis, whereas the outcome of malignant thyroid mesenchymal tumours is variable. Each thyroid mesenchymal tumour is characterised by its unique histopathology and immunohistochemistry. Because of the rarity and aggressive nature of malignant thyroid mesenchymal tumours, a multidisciplinary team-based approach should ideally be used in the management of these tumours. Comprehensive guidelines on the management of thyroid mesenchymal tumours are currently lacking. In this Review, we provide a detailed description of thyroid mesenchymal tumours, their clinical characteristics and tumour behaviour, and provide recommendations for the optimal management of these tumours.


Assuntos
Biomarcadores Tumorais , Neoplasias de Tecido Conjuntivo e de Tecidos Moles , Neoplasias da Glândula Tireoide , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/genética , Tomada de Decisão Clínica , Humanos , Neoplasias de Tecido Conjuntivo e de Tecidos Moles/química , Neoplasias de Tecido Conjuntivo e de Tecidos Moles/genética , Neoplasias de Tecido Conjuntivo e de Tecidos Moles/patologia , Neoplasias de Tecido Conjuntivo e de Tecidos Moles/terapia , Valor Preditivo dos Testes , Prognóstico , Neoplasias da Glândula Tireoide/química , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/terapia
4.
Mol Cell Biochem ; 411(1-2): 151-60, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26433955

RESUMO

Excessive alcohol consumption and dietary folate inadequacy are the main contributors leading to folate deficiency (FD). The present study was planned to study regulation of folate transport in conditions of FD and ethanol exposure in human embryonic kidney cell line. Also, the reversible nature of effects mediated by ethanol exposure and FD was determined by folate repletion and ethanol removal. For ethanol treatment, HEK293 cells were grown in medium containing 100 mM ethanol, and after treatment, one group of cells was shifted on medium that was free from ethanol. For FD treatment, cells were grown in folate-deficient medium followed by shifting of one group of cells on folate containing medium. FD as well as ethanol exposure resulted in an increase in folate uptake which was due to an increase in expression of folate transporters, i.e., reduced folate carrier, proton-coupled folate transporter, and folate receptor, both at the mRNA and protein level. The effects mediated by ethanol exposure and FD were reversible on removal of treatment. Promoter region methylation of folate transporters remained unaffected after FD and ethanol exposure. As far as transcription rate of folate transporters is concerned, an increase in rate of synthesis was observed in both ethanol exposure and FD conditions. Additionally, mRNA life of folate transporters was observed to be reduced by FD. An increased expression of folate transporters under ethanol exposure and FD conditions can be attributed to enhanced rate of synthesis of folate transporters.


Assuntos
Etanol/administração & dosagem , Deficiência de Ácido Fólico/metabolismo , Transportadores de Ácido Fólico/biossíntese , Ácido Fólico/metabolismo , Células HEK293 , Humanos
5.
Am J Manag Care ; 30(1): e4-e10, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38271568

RESUMO

OBJECTIVES: Few studies have evaluated racial and ethnic differences in several immune-mediated inflammatory diseases (IMIDs) or overlap syndrome (the co-occurrence of ≥ 2 IMIDs). We assessed associations between race and ethnicity and prevalence of IMIDs and overlap syndrome using US claims and electronic health records from 2021. STUDY DESIGN: Retrospective cohort study of 10.8 million adults. METHODS: We identified the 10 most prevalent IMIDs among frequently discussed IMIDs. We estimated associations between the 5 most prevalent IMIDs and overlap syndrome in Hispanic and non-Hispanic Asian and Black adults using non-Hispanic White adults as the referent and stratifying by sex and age (20-39, 40-59, and ≥ 60 years). RESULTS: Inflammatory bowel disease (IBD), systemic lupus erythematosus (SLE), multiple sclerosis (MS), and rheumatoid arthritis (RA) were the most prevalent IMIDs in all races and ethnicities. We observed positive associations (P < .0001) between Hispanic and non-Hispanic Black adults and SLE, Asian women of all ages and Asian men younger than 60 years and SLE, Black women younger than 60 years and MS, and Hispanic and non-White women 60 years or older and RA. Hispanic and non-White adults of all age groups had inverse associations (P < .0001) with IBD. Non-Hispanic Black adults of all ages and Hispanic and non-Hispanic Asian women 40 years or older had inverse associations (P < .0001) with psoriasis/psoriatic arthritis. Overlap syndrome was rare among all groups, with some variation in which IMIDs co-occurred. CONCLUSIONS: We found racial and ethnic differences in the prevalence and co-occurrence of IMIDs in this sample of US adults. Because misdiagnoses are relatively frequent for patients with IMIDs, awareness of racial and ethnic variations in IMIDs could aid early diagnosis and improve disease management.


Assuntos
Artrite Reumatoide , Doenças Autoimunes , Doenças Inflamatórias Intestinais , Lúpus Eritematoso Sistêmico , Adulto , Masculino , Humanos , Feminino , Pessoa de Meia-Idade , Grupos Raciais , Estudos Retrospectivos , Prevalência , Doenças Autoimunes/epidemiologia , Lúpus Eritematoso Sistêmico/epidemiologia , Artrite Reumatoide/epidemiologia , Doenças Inflamatórias Intestinais/epidemiologia , Agentes de Imunomodulação
6.
Environ Sci Pollut Res Int ; 31(10): 15788-15808, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38305978

RESUMO

This study attempts to examine the morphological, elemental and physical characteristics of PM10 over the Indian Himalayan Region (IHR) using FTIR and scanning electron microscopy-energy dispersive X-ray (SEM-EDX) analysis. The study aimed at source identification of PM10 by exploring the inorganic ions, organic functional groups, morphology and elemental characteristics. The pollution load of PM10 was estimated as 63 ± 22 µg m-3; 53 ± 16 µg m-3; 67 ± 26 µg m-3 and 55 ± 11 µg m-3 over Mohal-Kullu, Almora, Nainital and Darjeeling, respectively. ATR-FTIR spectrum analysis revealed the existence of inorganic ions (SiO44-, TiO2, SO42-, SO3-, NO3-, NO2-, CO32-, HCO3-, NH4+) and organic functional groups (C-C, C-H, C=C, C≡C, C=O, N-H, C≡N, C=N, O-H, cyclic rings, aromatic compounds and some heterogeneous groups) in PM10 which may arise from geogenic, biogenic and anthropogenic sources. The morphological and elemental characterization was performed by SEM-EDX, inferring for geogenic origin (Al, Na, K, Ca, Mg and Fe) due to the presence of different morphologies (irregular, spherical, cluster, sheet-like solid deposition and columnar). In contrast, particles having biogenic and anthropogenic origins (K, S and Ba) have primarily spherical with few irregular particles at all the study sites. Also, the statistical analysis ANOVA depicts that among all the detected elements, Na, Al, Si, S and K are site-specific in nature as their mean of aw% significantly varied for all the sites. The trajectory analysis revealed that the Uttarakhand, Jammu and Kashmir, the Thar Desert, Himachal Pradesh, Pakistan, Afghanistan, Nepal, Sikkim, the Indo-Gangetic Plain (IGP) and the Bay of Bengal (BoB) contribute to the increased loading of atmospheric pollutants in various locations within the IHR.


Assuntos
Poluentes Atmosféricos , Material Particulado , Material Particulado/análise , Poluentes Atmosféricos/análise , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier , Estações do Ano , Monitoramento Ambiental , Índia , Aerossóis/análise , Íons
7.
Artigo em Inglês | MEDLINE | ID: mdl-36734898

RESUMO

Dilated cardiomyopathy (DCM) is distinguished by ventricular chamber expansion, systolic dysfunction, and normal left ventricular (LV) wall thickness, and is mainly caused due to genetic or environmental factors; however, its aetiology is undetermined in the majority of patients. The focus of this work is on pathogenesis, small animal models, as well as the herbal medicinal approach, and the most recent advances in imaging modalities for patients with dilated cardiomyopathy. Several small animal models have been proposed over the last few years to mimic various pathomechanisms that contribute to dilated cardiomyopathy. Surgical procedures, gene mutations, and drug therapies are all characteristic features of these models. The pros and cons, including heart failure stimulation of extensively established small animal models for dilated cardiomyopathy, are illustrated, as these models tend to procure key insights and contribute to the development of innovative treatment techniques for patients. Traditional medicinal plants used as treatment in these models are also discussed, along with contemporary developments in herbal therapies. In the last few decades, accurate diagnosis, proper recognition of the underlying disease, specific risk stratification, and forecasting of clinical outcome, have indeed improved the health of DCM patients. Cardiac magnetic resonance (CMR) is the bullion criterion for assessing ventricular volume and ejection fraction in a reliable and consistent direction. Other technologies, like strain analysis and 3D echocardiography, have enhanced this technique's predictive and therapeutic potential. Nuclear imaging potentially helps doctors pinpoint the causative factors of left ventricular dysfunction, as with cardiac sarcoidosis and amyloidosis.


Assuntos
Cardiomiopatia Dilatada , Insuficiência Cardíaca , Disfunção Ventricular Esquerda , Humanos , Cardiomiopatia Dilatada/diagnóstico por imagem , Cardiomiopatia Dilatada/tratamento farmacológico , Cardiomiopatia Dilatada/etiologia , Volume Sistólico , Coração , Insuficiência Cardíaca/complicações , Imagem Multimodal/efeitos adversos
8.
Indian J Med Res ; 136(5): 758-65, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23287122

RESUMO

BACKGROUND & OBJECTIVES: Folate deficiency is a public health problem and is the most notable for its association with neural tube defect in developing embryo, megaloblastic anaemia, cancers and cardiovascular diseases. The mechanisms of the intestinal folate uptake process have been earlier characterized. However, much less is known about regulation. In this study we evaluated the mechanistic insights of folate absorption in an in vivo model of folate deficiency. METHODS: Male Wistar rats were fed folate-containing diet (2 mg/kg folic acid) or a folic acid-free diet over 3 months and folate transport was studied in intestinal brush border membrane vesicles (BBMV). RESULTS: The characterization of the folate transport system in intestinal brush border membrane (BBM) suggested it to be a carrier mediated, acidic pH stimulated, and Na⁺ independent. Folate deficiency increased the folate transport by altering the Vmax without changing the Km of folate transport process. The increased transport efficiency of the BBM was associated with upregulation of folate transporters at both mRNA and protein level. INTERPRETATION & CONCLUSIONS: Folate deficiency resulted in significant upregulation of intestinal folate uptake, by increasing number of transporters without any change in specificity of transporters towards its substrate. The observed upregulation was associated with significant increase in reduced folate carrier (RFC) and proton coupled folate transporter (PCFT) expressions, suggesting the transcriptional and translational regulation of folate uptake during folate deficiency.


Assuntos
Modelos Animais de Doenças , Deficiência de Ácido Fólico/metabolismo , Ácido Fólico/metabolismo , Animais , Sequência de Bases , Transporte Biológico , Metilação de DNA , Primers do DNA , Dieta , Ácido Fólico/administração & dosagem , Masculino , Microvilosidades/metabolismo , Ratos , Ratos Wistar
9.
Toxicol Res (Camb) ; 11(1): 206-214, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35237425

RESUMO

Type 2 diabetes mellitus (T2DM) is a metabolic disease characterized by reduced insulin sensitivity and dysfunction of ß-cells. Although the increasing prevalence of diabetes worldwide is largely attributed to genetic predisposition or lifestyle factors (insufficient physical activity), and caloric intake. Environmental factors, exposure to xenobiotics and heavy metals have also been reported to be causative factors of T2DM. At this juncture, we, through our work unveil a plausible link between Pb2+ exposure and diabetes mellitus, and delineated a comprehensive understanding of the potential mechanisms of Pb2+-induced ß-cells dysfunction. In our in vivo observations, we found that Pb2+ exposure strongly reduced glucose-stimulated insulin secretion and diminished functional pancreatic ß-cell mass. Mechanistically, we found that Pb2+ downregulates intracellular cAMP level via hyper-activating Ca2+/calmodulin-dependent 3',5'-cyclic nucleotide phosphodiesterase 1C and thereby reduces glucose-stimulated insulin secretion. Further, we report that Pb2+ inhibited mitochondrial adenosine triphosphate production and also identified Pb2+ as a negative regulator of ß-cell proliferation via Ca2+/calmodulin-dependent protein kinase kinases-pAMPK-pRaptor axis. Together, our findings strongly reinforce Pb2+ to hijack the physiological role of calcium ions, by mimicking Ca2+ within pancreatic ß-cell and thereby stands as a diabetogenic xenobiotic.

10.
BioTechnologia (Pozn) ; 102(3): 307-319, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-36606148

RESUMO

Invasive alien species are non-native plant species that displace native species and pose adverse effects to environment, ecosystem, economy, and human health by diminishing the growth of native plants and by exhibiting higher stress tolerance. In our present study, four invasive alien species, namely Lantana camara, Parthenium hysterophorous, Ricinus communis, and Ageratum conyzoides, were studied from different locations. Plants growing under natural environmental conditions were sampled at random in the vicinity of Jalandhar. To gain insights into the biochemical basis of invasiveness of these plants, the samples were subjected to chemical fingerprinting by using UV-Vis, fluorescent, and Fourier transform-infrared (FT-IR) techniques under natural abiotic stress conditions (moderate and hot conditions). Indices of oxidative stress, such as malondialdehyde (MDA), were also studied. MDA levels were enhanced under hot conditions. Elevated peaks (major and minor) were observed in UV fingerprinting during adverse abiotic conditions. Fluorescent spectroscopy also validated the enhanced levels of secondary metabolites. FT-IR spectroscopy confirmed the presence of alkaloids and phenolics during stress conditions. Peaks were identified as rutin, vanillic acid, ascorbic acid, and glutathione reduced. The obtained results showed that under stressful conditions, the studied plants may produce an increased level of metabolites that might play a role in minimizing the oxidative stress faced by these plants. It was concluded that the studied plants, namely P. hysterophorus, L. camara, R. communis, and A. conyzoides, have the potential to cope with abiotic stress such as high temperature, which could be the reason for their invasiveness and vast adaptability.

11.
Clin Cancer Res ; 27(5): 1399-1409, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33355247

RESUMO

PURPOSE: The goal of this study was to analyze the role of somatostatin receptor type 2 (SSTR2) as a molecular target for the imaging and treatment of thyroid cancer through analysis of SSTR2 expression and its epigenetic modulation and testing tumor uptake of different radiolabeled SSTR2 analogues. EXPERIMENTAL DESIGN: We analyzed SSTR2 expression by immunostaining of 92 thyroid cancer tissue samples and quantified standard uptake values (SUVmax) of SSTR2 analogue, 68Ga-DOTA-TATE, by PET/CT imaging in 25 patients with metastatic thyroid cancer. We utilized human thyroid cancer cell lines characterized by differential SSTR2 expression (TT, BCPAP, and FTC133) and rat pancreatic cell line (AR42J) with intrinsically high SSTR2 expression for functional in vitro studies. SSTR2-high (AR42J) and SSTR2-low (FTC133) xenograft mouse models were used to test the uptake of radiolabeled SSTR2 analogues and their therapeutic efficacy in vivo. RESULTS: Thyroid cancer had a higher SSTR2 expression than normal thyroid. Hurthle cell thyroid cancer was characterized by the highest 68Ga-DOTA-TATE uptake [median SUVmax, 16.5 (7.9-29)] than other types of thyroid cancers. In vivo studies demonstrated that radiolabeled DOTA-EB-TATE is characterized by significantly higher tumor uptake than DOTA-TATE (P < 0.001) and DOTA-JR11 (P < 0.001). Treatment with 177Lu-DOTA-EB-TATE extended survival and reduced tumor size in a mouse model characterized by high somatostatin (SST) analogues uptake (SUVmax, 15.16 ± 4.34), but had no effects in a model with low SST analogues uptake (SUVmax, 4.8 ± 0.27). CONCLUSIONS: A novel SST analogue, 177Lu-DOTA-EB-TATE, has the potential to be translated from bench to bedside for the targeted therapy of patients characterized by high uptake of SST analogues in metastatic lesions.


Assuntos
Compostos Radiofarmacêuticos/administração & dosagem , Receptores de Somatostatina/metabolismo , Somatostatina/análogos & derivados , Neoplasias da Glândula Tireoide/tratamento farmacológico , Adulto , Animais , Apoptose , Proliferação de Células , Feminino , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos Nus , Camundongos SCID , Pessoa de Meia-Idade , Metástase Neoplásica , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Prognóstico , Compostos Radiofarmacêuticos/metabolismo , Receptores de Somatostatina/química , Somatostatina/administração & dosagem , Somatostatina/metabolismo , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/patologia , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Cancers (Basel) ; 12(8)2020 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-32751138

RESUMO

The knowledge on thyroid cancer biology has grown over the past decade. Thus, diagnostic and therapeutic strategies to manage thyroid cancer are rapidly evolving. With new insights into tumor biology and cancer genetics, several novel therapies have been approved for the treatment of thyroid cancer. Tyrosine kinase inhibitors (TKIs), such as lenvatinib and sorafenib, have been successfully utilized for the treatment of radioactive iodine (RAI)-refractory metastatic differentiated thyroid cancer (DTC). In addition, pretreatment with mitogen-activated protein kinase (MAPK) inhibitors (trametinib and selumetinib) has been shown to restore RAI avidity in previously RAI-refractory DTCs. Local therapies, such as external beam radiation and radiofrequency/ethanol ablation, have also been employed for treatment of DTC. Vandetanib and cabozantinib are the two TKIs currently approved by the Food and Drug Administration (FDA) for the treatment of medullary thyroid cancer (MTC). Other novel therapies, such as peptide receptor radionuclide therapy and carcinoembryonic antigen (CEA) vaccine, have also been utilized in treating MTC. Ongoing trials on selective rearranged-during-transfection (RET) protooncogene inhibitors, such as LOXO-292 and BLU-667, have demonstrated promising results in the treatment of metastatic MTC resistant to non-selective TKIs. The FDA-approved BRAF/MEK inhibitor combination of dabrafenib and trametinib has revolutionized treatment of BRAFV600E mutation positive anaplastic thyroid cancer. Several other emerging classes of medications, such as gene fusion inhibitors and immune checkpoint inhibitors, are being actively investigated in several clinical trials. In this review, we describe the molecular landscape of thyroid cancer and novel targeted therapies and treatment combinations available for the treatment of metastatic thyroid cancer.

13.
Cancers (Basel) ; 12(9)2020 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-32911610

RESUMO

The nuclear-encoded subunit 4 of cytochrome c oxidase (COX4) plays a role in regulation of oxidative phosphorylation and contributes to cancer progression. We sought to determine the role of COX4 in differentiated (DTC) and medullary (MTC) thyroid cancers. We examined the expression of COX4 in human thyroid tumors by immunostaining and used shRNA-mediated knockdown of COX4 to evaluate its functional contributions in thyroid cancer cell lines. In human thyroid tissue, the expression of COX4 was higher in cancers than in either normal thyroid (p = 0.0001) or adenomas (p = 0.001). The level of COX4 expression correlated with tumor size (p = 0.04) and lymph-node metastases (p = 0.024) in patients with MTCs. COX4 silencing had no effects on cell signaling activation and mitochondrial respiration in DTC cell lines (FTC133 and BCPAP). In MTC-derived TT cells, COX4 silencing inhibited p70S6K/pS6 and p-ERK signaling, and was associated with decreased oxygen consumption and ATP production. Treatment with potassium cyanide had minimal effects on FTC133 and BCPAP, but inhibited mitochondrial respiration and induced apoptosis in MTC-derived TT cells. Our data demonstrated that metastatic MTCs are characterized by increased expression of COX4, and MTC-derived TT cells are vulnerable to COX4 silencing. These data suggest that COX4 can be considered as a novel molecular target for the treatment of MTC.

14.
J Clin Med ; 9(8)2020 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-32748840

RESUMO

The detection of rare mutational targets in plasma (liquid biopsy) has emerged as a promising tool for the assessment of patients with cancer. We determined the presence of cell-free DNA containing the BRAFV600E mutations (cfBRAFV600E) in plasma samples from 57 patients with papillary thyroid cancer (PTC) with somatic BRAFV600E mutation-positive primary tumors using microfluidic digital PCR, and co-amplification at lower denaturation temperature (COLD) PCR. Mutant cfBRAFV600E alleles were detected in 24/57 (42.1%) of the examined patients. The presence of cfBRAFV600E was significantly associated with tumor size (p = 0.03), multifocal patterns of growth (p = 0.03), the presence of extrathyroidal gross extension (p = 0.02) and the presence of pulmonary micrometastases (p = 0.04). In patients with low-, intermediate- and high-risk PTCs, cfBRAFV600E was detected in 4/19 (21.0%), 8/22 (36.3%) and 12/16 (75.0%) of cases, respectively. Patients with detectable cfBRAFV600E were characterized by a 4.68 times higher likelihood of non-excellent response to therapy, as compared to patients without detectable cfBRAFV600E (OR (odds ratios), 4.68; 95% CI (confidence intervals)) 1.26-17.32; p = 0.02). In summary, the combination of digital polymerase chain reaction (dPCR) with COLD-PCR enables the detection of BRAFV600E in the liquid biopsy from patients with PTCs and could prove useful for the identification of patients with PTC at an increased risk for a structurally or biochemically incomplete or indeterminate response to treatment.

15.
Artigo em Inglês | MEDLINE | ID: mdl-32132976

RESUMO

Background: Thyroid ultrasound (US), fine needle aspiration biopsy (FNAB), and molecular testing have been widely used to stratify the risk of malignancy in thyroid nodules. The goal of this study was to investigate a novel diagnostic approach for cytologically indeterminate thyroid nodules (ITN) based upon a combination of US features and genetic alterations. Methods: We performed a pilot cohort study of patients with ITN (Bethesda III/IV), who underwent surgical treatment. Based on standardized sonographic patterns established by the American Thyroid Association (ATA), each ITN received an US score (XUS), ranging between 0 and 0.9 according to its risk of thyroid cancer (TC). DNA and RNA were extracted from pathologic material, available for all patients, and subjected to Oncomine™ Comprehensive Assay v2 (OCAv2) next-generation sequencing. Each genetic alteration was annotated based on its strength of association with TC and its sum served as the genomic classifier score (XGC). The total risk score (TRS) was the sum of XUS and XGC. ROC curves were generated to assess the diagnostic accuracy of XUS, XGC, and TRS. Results: The study cohort consisted of 50 patients (39 females and 11 males), aged 47.5 ± 14.8 years. Three patients were excluded due to molecular testing failure. Among the remaining 47 patients, 28 (59.6%) were diagnosed with TC. BRAFV600E was the most common mutation in papillary TC, PAX8-PPARG fusion was present in NIFTP, pathogenic variants of SLX4, ATM, and NRAS were found in Hürthle cell TC and RET mutations in medullary TC. The diagnostic accuracy of XGC and TRS was significantly higher compared with XUS (88 vs. 62.5%, p < 0.001; 85.2 vs. 62.5%, p < 0.001, respectively). However, this increased accuracy was due to significantly better sensitivity (80.7 vs. 34.6%, p < 0.001; 84.6 vs. 34.6%, p < 0.001, respectively) without improved specificity (94.7 vs. 90%, p = 0.55; 85.7 vs. 90%, p = 0.63, respectively). Conclusion: Molecular testing might not be necessary in ITN with high-risk US pattern (XUS = 0.9), as specificity of TC diagnosis based on Xus alone is sufficient and not improved with molecular testing. OCAv2 is useful in guiding the management of ITN with low-to-intermediate risk US features (XUS < 0.9), as it increases the accuracy of TC diagnosis.


Assuntos
Carcinoma Neuroendócrino/diagnóstico , Citodiagnóstico/métodos , Medição de Risco/métodos , Câncer Papilífero da Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/diagnóstico , Nódulo da Glândula Tireoide/diagnóstico , Ultrassonografia/métodos , Biomarcadores/análise , Carcinoma Neuroendócrino/diagnóstico por imagem , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Técnicas de Diagnóstico Molecular , Projetos Piloto , Prognóstico , Estudos Retrospectivos , Câncer Papilífero da Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Nódulo da Glândula Tireoide/diagnóstico por imagem
16.
J Mol Endocrinol ; 63(2): R17-R35, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31307011

RESUMO

Incidence of endocrine cancers is rising every year. Over the last decade, evidence has accumulated that demonstrates the anti-cancer effects of an anti-diabetic drug, metformin, in endocrine malignancies. We performed a literature review utilizing the PubMed, Medline and clinicaltrials.gov databases using the keyword 'metformin' plus the following terms: 'thyroid cancer', 'thyroid nodules', 'parathyroid', 'hyperparathyroidism', 'adrenal adenoma', 'Cushing syndrome', 'hyperaldosteronism', 'adrenocortical cancer', 'neuroendocrine tumor (NET)', 'pancreatic NET (pNET)', 'carcinoid', 'pituitary adenoma', 'pituitary neuroendocrine tumor (PitNET)', 'prolactinoma', 'pheochromocytoma/paraganglioma'. We found 37 studies describing the preclinical and clinical role of metformin in endocrine tumors. The available epidemiological data show an association between exposure of metformin and lower incidence of thyroid cancer and pNETs in diabetic patients. Metformin treatment has been associated with better response to cancer therapy in thyroid cancer and pNETs. Preclinical evidence suggests that the primary direct mechanisms of metformin action include inhibition of mitochondrial oxidative phosphorylation via inhibition of both mitochondrial complex I and mitochondrial glycerophosphate dehydrogenase, leading to metabolic stress. Decreased ATP production leads to an activation of a cellular energy sensor, AMPK, and subsequent downregulation of mTOR signaling pathway, which is associated with decreased cellular proliferation. We also describe several AMPK-independent mechanisms of metformin action, as well as the indirect mechanisms targeting insulin resistance. Overall, repositioning of metformin has emerged as a promising strategy for adjuvant therapy of endocrine tumors. The mechanisms of synergy between metformin and other anti-cancer agents need to be elucidated further to guide well-designed prospective trials on combination therapies in endocrine malignancies.


Assuntos
Diabetes Mellitus/tratamento farmacológico , Neoplasias das Glândulas Endócrinas/tratamento farmacológico , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico , Metformina/farmacologia , Metformina/uso terapêutico , Animais , Humanos , Transdução de Sinais/efeitos dos fármacos
17.
Front Oncol ; 9: 1092, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31750236

RESUMO

Background: Epidemiological data reveal that treatment with lithium, a mood stabilizer, is associated with decreased incidence and mortality of certain cancer types, such as melanoma. Therefore, repositioning of lithium as an anticancer agent has emerged as a promising strategy in oncology. Since lithium affects the physiology of several endocrine tissues, the goal of this study was to analyze the role of lithium in the pathogenesis and treatment of tumors of the endocrine system. Methods: The databases of PubMed, EMBASE, MEDLINE, were searched from January 1970 through February 2019 for articles including the keywords "lithium and"-"thyroid cancer," "thyroid nodule," "parathyroid adenoma," "parathyroid carcinoma," "pituitary adenoma," "pituitary neuroendocrine tumor," "neuroendocrine tumor," "carcinoid," "adrenal adenoma," "adrenal carcinoma," "pheochromocytoma/paraganglioma." Preclinical in vitro and in vivo studies as well as case series, retrospective cohort studies and prospective trials were selected for the analysis. Results: Treatment with lithium has been associated with a higher prevalence of thyroid enlargement, hypothyroidism and increased calcium levels due to parathyroid adenoma or hyperplasia, as one of the mechanisms of its action is to stimulate proliferation of normal follicular thyroid and parathyroid cells via activation of the Wnt signaling pathway. Supratherapeutic concentrations of lithium decrease the activity of glycogen synthase kinase-3ß (GSK-3ß), leading to cell cycle arrest in several in vitro cancer models including medullary thyroid cancer (TC), pheochromocytoma/paraganglioma and carcinoid. Growth inhibitory effects of lithium in vivo have been documented in medullary TC xenograft mouse models. Clinically, lithium has been used as an adjuvant agent to therapy with radioactive iodine (RAI), as it increases the residence time of RAI in TC. Conclusion: Patients chronically treated with lithium need to be screened for hypothyroidism, goiter, and hyperparathyroidism, as the prevalence of these endocrine abnormalities is higher in lithium-treated patients than in the general population. The growth inhibitory effects of lithium in medullary TC, pheochromocytoma/paraganglioma and carcinoid were achieved with supratherapeutic concentrations of lithium thus limiting its translational perspective. Currently available clinical data on the efficacy of lithium in the therapy of endocrine tumors in human is limited and associated with conflicting results.

18.
Sci Rep ; 9(1): 17602, 2019 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-31772242

RESUMO

DNA methylation, a central component of the epigenetic network is altered in response to nutritional influences. In one-carbon cycle, folate acts as a one-carbon carrier and vitamin B12 acts as co-factor for the enzyme methionine synthase. Both folate and vitamin B12 are the important regulators of DNA methylation which play an important role in development in early life. Previous studies carried out in this regard have shown the individual effects of these vitamins but recently the focus has been to study the combined effects of both the vitamins during pregnancy. Therefore, this study was planned to elucidate the effect of the altered dietary ratio of folate and B12 on the expression of transporters, related miRNAs and DNA methylation in C57BL/6 mice. Female mice were fed diets with 9 combinations of folate and B12 for 4 weeks. They were mated and off-springs born (F1) were continued on the same diet for 6 weeks post-weaning. Maternal and fetal (F2) tissues were collected at day 20 of gestation. Deficient state of folate led to an increase in the expression of folate transporters in both F1 and F2 generations, however, B12 deficiency (BDFN) also led to an increase in the expression in both the generations. B12 transporters/proteins were found to be increased with B12 deficiency in F1 and F2 generations except for TC-II in the kidney which was found to be decreased in the F1 generation. miR-483 was found to be increased with all conditions of folate and B12 in both F1 and F2 generations, however, deficient conditions of B12 led to an increase in the expression of miR-221 in both F1 and F2 generations. The level of miR-133 was found to be increased in BDFN group in F1 generation however; in F2 generation the change in expression was tissue and sex-specific. Global DNA methylation was decreased with deficiency of both folate and B12 in maternal tissues (F1) but increased with folate deficiency in placenta (F1) and under all conditions in fetal tissues (F2). DNA methyltransferases were overall found to be increased with deficiency of folate and B12 in both F1 and F2 generations. Results suggest that the dietary ratio of folate and B12 resulted in altered expression of transporters, miRNAs, and genomic DNA methylation in association with DNMTs.


Assuntos
Metilação de DNA , Dieta , Deficiência de Ácido Fólico/metabolismo , Ácido Fólico/administração & dosagem , Exposição Materna , MicroRNAs/genética , Exposição Paterna , Complicações na Gravidez/metabolismo , Deficiência de Vitamina B 12/metabolismo , Vitamina B 12/administração & dosagem , Animais , Encéfalo/embriologia , Encéfalo/metabolismo , Proteínas de Transporte/biossíntese , Proteínas de Transporte/genética , DNA (Citosina-5-)-Metiltransferases/biossíntese , DNA (Citosina-5-)-Metiltransferases/genética , Feminino , Retardo do Crescimento Fetal/etiologia , Retardo do Crescimento Fetal/genética , Feto/metabolismo , Ácido Fólico/sangue , Deficiência de Ácido Fólico/genética , Regulação da Expressão Gênica no Desenvolvimento , Homocisteína/sangue , Rim/embriologia , Rim/metabolismo , Fígado/embriologia , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/biossíntese , Placenta/metabolismo , Gravidez , Complicações na Gravidez/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Vitamina B 12/sangue , Deficiência de Vitamina B 12/genética
19.
Front Oncol ; 9: 905, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31620364

RESUMO

Background: Analysis of plasma circulating cell-free DNA integrity (cfDI) has emerged as a promising tool in the diagnosis of malignant vs. benign tumors. There is limited data on the role of cfDI in thyroid cancer. The goal of this study was to analyze cfDI as a biomarker of malignancy in patients with cytologically indeterminate thyroid nodules. Methods: The cfDI was measured in the plasma of patients with cytologically indeterminate thyroid nodules. All patients underwent plasma collection within 24-72 h before surgical treatment for thyroid nodules. Additionally, samples were collected from seven patients via the vein draining the thyroid and peripheral vein during surgery. Quantitative real-time PCR was performed on the isolated cell-free DNA using two different primer sets (115 and 247 bp) to amplify consensus ALU sequences. The cfDI was calculated as the ratio of ALU247 to ALU115. Results: All data are given as median [25th-75th percentile]. The study group consisted of 67 patients with 100 nodules, 80.6% (54/67) women, aged 43 [33-60] years. There was no difference in cfDI between 29 patients with benign nodules (0.49 [0.41-0.59]) and 38 patients with malignant lesions (0.45 [0.36-0.57], p = 0.19). There was no difference in cfDI in the vein draining the thyroid (0.47 [0.24-1.05]) and peripheral vein (0.48 [0.36-0.56], p = 0.44). In comparison to thyroid cancer patients, patients with benign nodules were characterized by significantly higher concentrations of ALU115 (1,064 [529-2,960] vs. 411 [27-1,049] ng/ml; p = 0.002) and ALU247 (548 [276-1,894] vs. 170 [17-540] ng/ml; p = 0.0005), most likely because benign tumors were larger (3, [1.8-4.1 cm]) than malignant lesions (0.7 [0.23-1.45], p < 0.0001). Women had significantly lower cfDI (0.45 [0.27-0.54]) than men (0.56 [0.44-0.8], p = 0.011). Conclusion: The cfDI measured in the vein draining the thyroid is similar to the cfDI measured in the antecubital vein, validating cfDI measurements by peripheral liquid biopsy. Analysis of cfDI needs to be stratified by patients gender. In contrast to its diagnostic utility in aggressive cancers, cfDI has limited utility as a biomarker of malignancy in cytologically indeterminate thyroid nodules.

20.
Clin Cancer Res ; 24(16): 4030-4043, 2018 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-29691295

RESUMO

Purpose: Mitochondrial glycerophosphate dehydrogenase (MGPDH) is the key enzyme connecting oxidative phosphorylation (OXPHOS) and glycolysis as well as a target of the antidiabetic drug metformin in the liver. There are no data on the expression and role of MGPDH as a metformin target in cancer. In this study, we evaluated MGPDH as a potential target of metformin in thyroid cancer and investigated its contribution in thyroid cancer metabolism.Experimental Design: We analyzed MGPDH expression in 253 thyroid cancer and normal tissues by immunostaining and examined its expression and localization in thyroid cancer-derived cell lines (FTC133, BCPAP) by confocal microscopy. The effects of metformin on MGPDH expression were determined by qRT-PCR and Western blot analysis. Seahorse analyzer was utilized to assess the effects of metformin on OXPHOS and glycolysis in thyroid cancer cells. We analyzed the effects of metformin on tumor growth and MGPDH expression in metastatic thyroid cancer mouse models.Results: We show for the first time that MGPDH is overexpressed in thyroid cancer compared with normal thyroid. We demonstrate that MGPDH regulates human thyroid cancer cell growth and OXPHOS rate in vitro Metformin treatment is associated with downregulation of MGPDH expression and inhibition of OXPHOS in thyroid cancer in vitro Cells characterized by high MGPDH expression are more sensitive to OXPHOS-inhibitory effects of metformin in vitro and growth-inhibitory effects of metformin in vitro and in vivoConclusions: Our study established MGPDH as a novel regulator of thyroid cancer growth and metabolism that can be effectively targeted by metformin. Clin Cancer Res; 24(16); 4030-43. ©2018 AACR.


Assuntos
Glicerolfosfato Desidrogenase/genética , Metformina/farmacologia , Mitocôndrias/efeitos dos fármacos , Neoplasias da Glândula Tireoide/tratamento farmacológico , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Glicólise/efeitos dos fármacos , Xenoenxertos , Humanos , Camundongos , Mitocôndrias/enzimologia , Fosforilação Oxidativa/efeitos dos fármacos , Neoplasias da Glândula Tireoide/enzimologia , Neoplasias da Glândula Tireoide/patologia
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