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Scientists in this field often joke, "If you don't have a mechanism, say it's ROS." Seemingly connected to every biological process ever described, reactive oxygen species (ROS) have numerous pleiotropic roles in physiology and disease. In some contexts, ROS act as secondary messengers, controlling a variety of signaling cascades. In other scenarios, they initiate damage to macromolecules. Finally, in their worst form, ROS are deadly to cells and surrounding tissues. A set of molecules with detoxifying abilities, termed antioxidants, is the direct counterpart to ROS. Notably, antioxidants exist in the public domain, touted as a "cure-all" for diseases. Research has disproved many of these claims and, in some cases, shown the opposite. Of all the diseases, cancer stands out in its paradoxical relationship with antioxidants. Although the field has made numerous strides in understanding the roles of antioxidants in cancer, many questions remain.
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Antioxidantes , Neoplasias , Humanos , Espécies Reativas de Oxigênio , Estresse Oxidativo , Neoplasias/genética , Transdução de SinaisRESUMO
Reactive oxygen species (ROS) are produced by both enzymatic and non-enzymatic systems within eukaryotic cells and play important roles in cellular physiology and pathophysiology. Although physiological concentrations are crucial for ensuring cell survival, ROS overproduction is detrimental to cells, and considered key-factors for the development of several diseases, such as neurodegenerative diseases, cardiovascular disorders, and cancer. Cancer cells are usually submitted to higher ROS levels that further stimulate malignant phenotype through stimulus to sustained proliferation, death evasion, angiogenesis, invasiveness, and metastasis. The role of ROS on breast cancer etiology and progression is being progressively elucidated. However, less attention has been given to the development of redox system-targeted strategies for breast cancer therapy. In this review, we address the basic mechanisms of ROS production and scavenging in breast tumor cells, and the emerging possibilities of breast cancer therapies targeting ROS homeostasis.
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Neoplasias da Mama/genética , Neoplasias da Mama/terapia , Estresse Oxidativo/genética , Espécies Reativas de Oxigênio/metabolismo , Antioxidantes/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Proliferação de Células/genética , Feminino , Humanos , Invasividade Neoplásica/genéticaRESUMO
OBJECTIVE: Ionizing radiation generates genomic instability by promoting the accumulation of chromosomal rearrangements. The oncogenic translocation RET/PTC1 is present in more than 70% of radiation-induced thyroid cancers. Both RET and CCDC6, the genes implicated in RET/PTC1, are found within common fragile sites - chromosomal regions prone to DNA breakage during slight replication stress. Given that irradiated cells become more susceptible to genomic destabilization due to the accumulation of replication-stress-related double-strand breaks (DSBs), we explored whether RET and CCDC6 exhibit DNA breakage under replicative stress several days post-irradiation of thyroid cells. METHODS: We analyzed the dynamic of DNA replication in human thyroid epithelial cells (HThy-ori-3.1) 4 days post a 5-Gy exposure using molecular DNA combing. The DNA replication schedule was evaluated through replication-timing experiments. We implemented a ChIP-qPCR assay to determine whether the RET and CCDC6 genes break following irradiation. RESULTS: Our study indicates that replicative stress, occurring several days post-irradiation in thyroid cells, primarily causes DSBs in the RET gene. We discovered that both the RET and CCDC6 genes undergo late replication in thyroid cells. However, only RET's replication rate is notably delayed after irradiation. CONCLUSION: The findings suggest that post-irradiation in the RET gene causes a breakage in the replication fork, which could potentially invade another genomic area, including CCDC6. As a result, this could greatly contribute to the high prevalence of chromosomal RET/PTC rearrangements seen in patients exposed to external radiation.
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BACKGROUND: Among other structures, nuclear grooves are vastly found in papillary thyroid carcinoma (PTC). Considering that the application of artificial intelligence in thyroid cytology has potential for diagnostic routine, our goal was to develop a new supervised convolutional neural network capable of identifying nuclear grooves in Diff-Quik stained whole-slide images (WSI) obtained from thyroid fineneedle aspiration. METHODS: We selected 22 Diff-Quik stained cytological slides with cytological diagnosis of PTC and concordant histological diagnosis. Each of the slides was scanned, forming a WSI. Images that contained the region of interest were obtained, followed by pre-formatting, annotation of the nuclear grooves and data augmentation techniques. The final dataset was divided into training and validation groups in a 7:3 ratio. RESULTS: This is the first artificial intelligence model based on object detection applied to nuclear structures in thyroid cytopathology. A total of 7,255 images were obtained from 22 WSI, totaling 7,242 annotated nuclear grooves. The best model was obtained after it was submitted 15 times with the train dataset (14th epoch), with 67% true positives, 49.8% for sensitivity and 43.1% for predictive positive value. CONCLUSIONS: The model was able to develop a structure predictor rule, indicating that the application of an artificial intelligence model based on object detection in the identification of nuclear grooves is feasible. Associated with a reduction in interobserver variability and in time per slide, this demonstrates that nuclear evaluation constitutes one of the possibilities for refining the diagnosis through computational models.
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Introduction: The type 2 deiodinase and its Thr92Ala-DIO2 polymorphism have been linked to clinical outcomes in acute lung injury and coronavirus disease 2019 (COVID-19). Objective: The objective was to identify a potential association between Thr92Ala-DIO2 polymorphism and body composition (appendicular muscle mass, myosteatosis, and fat distribution) and to determine whether they reflect the severity or mortality associated with the disease. Methods: In this prospective cohort study (June-August 2020), 181 patients hospitalized with moderate-to-severe COVID-19 underwent a non-contrast-enhanced computed tomography (CT) of the thorax to assess body composition, laboratory tests, and genotyping for the Thr92Ala-DIO2 polymorphism. Results: In total, 181 consecutive patients were stratified into three subgroups according to the genotype: Thr/Thr (n = 64), Thr/Ala (n = 96), and Ala/Ala (n = 21). The prevalence of low muscle area (MA) (< 92 cm²) was 52.5%. Low MA was less frequent in Ala/Thr patients (44.8%) than in Thr/Thr (60.9%) or Ala/Ala patients (61.9%) (P = 0.027). Multivariate logistic regression analysis confirmed that the Thr/Ala allele was associated with a reduced risk of low MA (41% to 69%) and myosteatosis (62% to 72%) compared with Thr/Thr + Ala/Ala (overdominant model). Kaplan-Meier curves showed that patients with low muscle mass and homozygosity had lower survival rates than the other groups. Notably, the heterozygotes with MA ≥92 cm² exhibited the best survival rate. Conclusion: Thr92Ala-DIO2 heterozygosity is associated with increased skeletal MA and less myosteatosis in patients with COVID-19. The protective effect of Thr92Ala-DIO2 heterozygosity on COVID-19 mortality is restricted to patients with reduced MA.
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COVID-19 , Músculo Esquelético , SARS-CoV-2 , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Composição Corporal/genética , COVID-19/genética , COVID-19/diagnóstico por imagem , Genótipo , Heterozigoto , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/patologia , Estudos Prospectivos , Tomografia Computadorizada por Raios XRESUMO
Cells rely on antioxidants to survive. The most abundant antioxidant is glutathione (GSH). The synthesis of GSH is non-redundantly controlled by the glutamate-cysteine ligase catalytic subunit (GCLC). GSH imbalance is implicated in many diseases, but the requirement for GSH in adult tissues is unclear. To interrogate this, we have developed a series of in vivo models to induce Gclc deletion in adult animals. We find that GSH is essential to lipid abundance in vivo. GSH levels are highest in liver tissue, which is also a hub for lipid production. While the loss of GSH does not cause liver failure, it decreases lipogenic enzyme expression, circulating triglyceride levels, and fat stores. Mechanistically, we find that GSH promotes lipid abundance by repressing NRF2, a transcription factor induced by oxidative stress. These studies identify GSH as a fulcrum in the liver's balance of redox buffering and triglyceride production.
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Glutamato-Cisteína Ligase , Glutationa , Fígado , Fator 2 Relacionado a NF-E2 , Triglicerídeos , Animais , Glutationa/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Fator 2 Relacionado a NF-E2/genética , Fígado/metabolismo , Glutamato-Cisteína Ligase/metabolismo , Glutamato-Cisteína Ligase/genética , Camundongos , Triglicerídeos/metabolismo , Estresse Oxidativo , Masculino , Metabolismo dos Lipídeos , Camundongos Knockout , Camundongos Endogâmicos C57BL , Oxirredução , Lipogênese/genéticaRESUMO
Cells respond to amino acid depletion by activating stress responses. A recent study by Swanda et al. reveals that a decrease in lysosomal cystine triggers a novel stress response that transcriptionally activates ATF4 and protects cells from ferroptosis. A synthetic mRNA, CysRx, can prevent ATF4 activation and enhance antitumor effects.
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Cistina , Ferroptose , Humanos , Cistina/metabolismo , Cisteína , Aminoácidos , Lisossomos/metabolismoRESUMO
Cells rely on antioxidants to survive. The most abundant antioxidant is glutathione (GSH). The synthesis of GSH is non-redundantly controlled by the glutamate-cysteine ligase catalytic subunit (GCLC). GSH imbalance is implicated in many diseases, but the requirement for GSH in adult tissues is unclear. To interrogate this, we developed a series of in vivo models to induce Gclc deletion in adult animals. We find that GSH is essential to lipid abundance in vivo. GSH levels are reported to be highest in liver tissue, which is also a hub for lipid production. While the loss of GSH did not cause liver failure, it decreased lipogenic enzyme expression, circulating triglyceride levels, and fat stores. Mechanistically, we found that GSH promotes lipid abundance by repressing NRF2, a transcription factor induced by oxidative stress. These studies identify GSH as a fulcrum in the liver's balance of redox buffering and triglyceride production.
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Coronavirus disease 2019 (COVID-19) was characterized as a pandemic in March, 2020 by the World Health Organization. COVID-19 is a respiratory syndrome that can progress to acute respiratory distress syndrome, multiorgan dysfunction, and eventually death. Despite being considered a respiratory disease, it is known that other organs and systems can be affected in COVID-19, including the thyroid gland. Thyroid gland, as well as hypothalamus and pituitary, which regulate the functioning of most endocrine glands, express angiotensin-converting enzyme 2 (ACE2), the main protein that functions as a receptor to which SARS-CoV-2 binds to enter host cells. In addition, thyroid gland is extremely sensitive to changes in body homeostasis and metabolism. Immune system cells are targets for thyroid hormones and T3 and T4 modulate specific immune responses, including cell-mediated immunity, natural killer cell activity, the antiviral action of interferon (IFN) and proliferation of T- and B-lymphocytes. However, studies show that patients with controlled hypothyroidism and hyperthyroidism do not have a higher prevalence of COVID-19, nor do they have a worse prognosis when infected with the virus. On the other hand, retrospective observational studies, prospective studies, and case reports published in the last two years reported abnormal thyroid function related to acute SARS-CoV-2 infection or even several weeks after its resolution. Indeed, a variety of thyroid disorders have been documented in COVID-19 patients, including non-thyroidal illness syndrome (NTIS), subacute thyroiditis and thyrotoxicosis. In addition, thyroid disease has already been reported as a consequence of the administration of vaccines against SARS-CoV-2. Overall, the data revealed that abnormal thyroid function may occur during and in the convalescence post-COVID condition phase. Although the cellular and molecular mechanisms are not completely understood, the evidence suggests that the "cytokine storm" is an important mediator in this context. Thus, future studies are needed to better investigate the pathophysiology of thyroid dysfunction induced by COVID-19 at both molecular and clinical levels.
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COVID-19 , Doenças da Glândula Tireoide , Humanos , SARS-CoV-2/metabolismo , Vacinas contra COVID-19 , Estudos Prospectivos , Estudos Retrospectivos , Peptidil Dipeptidase A/metabolismo , Doenças da Glândula Tireoide/complicações , Doenças da Glândula Tireoide/epidemiologiaRESUMO
INTRODUCTION: The subjective evaluation of nuclear features in follicular-patterned lesions of the thyroid is a reason for diagnosis discordance. The assessment of nuclear features also varies whether the observation is performed optically or digitally. Our objective was to study the concordance among pathologists regarding the nuclear score (NS) evaluation in a series of follicular-patterned lesions, using optical versus three digital scanning protocols. METHODS: Three pathologists evaluated the NS in a 3mm2 area randomly selected from 20 hematoxylin-eosin slides representative of the respective 20 follicular-patterned thyroid lesions. The NS evaluation was performed using optical and three different scanning protocols in two scanners: P1000_20x, P1000_40x and DP200_20x. Kappa statistic (κ) and intraclass correlation coefficient (ICC) were obtained for intra- and interpathologist concordance. RESULTS: We recorded a good agreement among pathologists in the optical evaluation of the NS (ICC of 0.73). The concordance between optical versus digital observation had an almost perfect agreement for P1000_20x [κ = 0.85 (0.67-1.02); p < 0.0001] and a substantial agreement for both P1000_40x [κ = 0.69 (0.43-0.95) p = 0.002] and DP200_20x [κ = 0.77 (0.57-0.97); p = 0.001]. The P1000_20x protocol had the best intrapathologist concordance with the optical method, classified as almost perfect agreement for pathologists A (80%) and B (85%), and substantial agreement for pathologist C (70%). CONCLUSION: Digital observation of the WSI is valid for the NS evaluation in follicular-patterned thyroid lesions, with good agreement among pathologists and between optical and scanning protocols. Performance studies and validation procedures cannot be avoided in this setting to prevent diagnostic discordance due to the scanning process.
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Núcleo Celular , Glândula Tireoide , Núcleo Celular/patologia , Humanos , Variações Dependentes do Observador , Glândula Tireoide/diagnóstico por imagem , Glândula Tireoide/patologiaRESUMO
OBJECTIVES: This study aims to investigate if a sampling method using virtual networks is feasible to survey AS adoption among this "hard-to-reach" population of Brazilian doctors. METHODS: An online piloted 11-point structured survey questionnaire (designed using Googleforms®) probed the actual treatment patterns for adult patients with PTMCs, including treatment decision-making nonoperative options, was undertaken between 10 November and 30 November 2020. Participants were reached by the mobile phone Application (APP) and a snowball sampling strategy was used to recruit a total of 4783 members (maximum number of potential reach), which is the total of doctors of the all 21 social media WhatsApp® groups. RESULTS: From a total of 4783 members (maximum number of potential reach), there were 657 (13.7%) doctors (actual reach) who clicked the web link of the questionnaire, out of whom 512 (10.7%) fully completed the online survey. Among the survey respondents, 361 were endocrinologists (70.5%) and 151 were surgeons (29.5%). Overall, for low-risk PTMCs in an elderly patient, 118 responders (23%) recommend AS, while 390 (76%) recommend immediate surgery as the management, including lobectomy (18.5%) and Total Thyroidectomy (58.2%). The present responders tended to recommend surgery for PTMCs that were located adjacent to the dorsal surface of the thyroid, were multiple, or raised the size during the follow-up. CONCLUSION: Using snowball sampling strategy as an innovative route to conduct surveys was feasible and applicable but the rate of response was still very low. Our data also suggests the need to investigate if AS is embraced by Brazilian doctors.
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Neoplasias da Glândula Tireoide , Adulto , Humanos , Idoso , Neoplasias da Glândula Tireoide/cirurgia , Conduta Expectante , Tireoidectomia , BrasilRESUMO
Introduction: The severity of coronavirus disease 2019 (COVID-19) has been positively correlated with several comorbidities. The primary outcome of the study was to assess the relationship between the mortality and severity of COVID-19 and obesity classes according to BMI, visceral adipose tissue (VAT) area, s.c. adipose tissue area, muscle area (MA), and leptin levels. Methods: In this prospective cohort study, 200 patients hospitalized with moderate-to-severe COVID-19 underwent an unenhanced CT of the thorax and laboratory tests, and leptin levels between June and August 2020 were obtained. Results: Our study included 200 patients (male 52%; mean age: 62 (49-74) years; obesity (BMI > 30): 51.5%)). Fifty-eight patients (23.5%) were admitted to the intensive care unit and 29 (14.5%) died. In multivariate logistic regression (corrected for leptin, sex, age, and serum biomarkers) and receiver operating characteristic curve analyses, high VAT > 150 cm2 (odds ratio (OR): 6.15; P < 0.002), MA < 92 cm2 (OR: 7.94; P < 0.005), and VAT/MA ratio > 2 (OR: 13.9; P < 0.0001) were independent risk factors for mortality. Indeed, the Kaplan-Meier curves showed that patients with MA < 92 cm2 and without obesity (BMI < 30) had a lower survival rate (hazard ratio between 3.89 and 9.66; P < 0.0006) than the other groups. Leptin levels were not related to mortality and severity. Conclusion: This prospective study reports data on the largest number of hospitalized severe COVID-19 patients and pinpoints VAT area and MA calculated by CT as predictors of COVID-19 mortality.
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CONTEXT: The type 2 deiodinase and its Thr92Ala-DIO2 polymorphism have been linked to clinical outcomes in acute lung injury and pulmonary fibrosis. OBJECTIVE: Our objectives were to evaluate were cumulative mortality during admission according to Thr92Ala-DIO2 polymorphism. METHODS: Here we conducted an observational, longitudinal, and prospective cohort study to investigate a possible association between the Thr92Ala-DIO2 polymorphism and intrahospital mortality from COVID-19 in adult patients admitted between June and August 2020. Blood biochemistry, thyroid function tests, length of stay, comorbidities, complications, and severity scores were also studied according to Thr92Ala-DIO2 polymorphism. RESULTS: In total, 220 consecutive patients (median age 62; 48-74 years) were stratified into 3 subgroups: Thr/Thr (nâ =â 79), Thr/Ala (nâ =â 119), and Ala/Ala (nâ =â 23). While the overall mortality was 17.3%, the lethality was lower in Ala/Thr patients (12.6%) than in Thr/Thr patients (21.7%) or Ala/Ala patients (23%). The heterozygous genotype (Thr/Ala) was associated with a 47% reduced risk of intrahospital mortality whereas univariate and multivariate logistic regression adjusted for multiple covariates revealed a reduction that ranged from 51% to 66%. The association of the Thr/Ala genotype with better clinical outcomes was confirmed in a metanalysis of 5 studies, including the present one. CONCLUSION: Here we provide evidence for a protective role played by Thr92Ala-DIO2 heterozygosity in patients with COVID-19. This protective effect follows an inheritance model known as overdominance, in which the phenotype of the heterozygote lies outside the phenotypical range of both homozygous.
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COVID-19 , Iodeto Peroxidase , COVID-19/genética , COVID-19/mortalidade , Heterozigoto , Mortalidade Hospitalar , Humanos , Iodeto Peroxidase/genética , Estudos Longitudinais , Polimorfismo de Nucleotídeo Único , Estudos Prospectivos , Iodotironina Desiodinase Tipo IIRESUMO
INTRODUCTION: Vandetanib is indicated for adults with advanced medullary thyroid cancer (MTC). OBJECTIVES: To describe the efficacy and toxicity profile of vandetanib treatment with a maximal follow-up of 11 years at Institut Gustave Roussy/France. METHODS: A review of the clinical files of the 76 MTC patients treated with vandetanib. Efficacy was estimated by markers and imaging. RESULTS: A total of 76 patients received vandetanib. Nine were excluded from efficacy analysis because lack of morphological data. The overall (N = 76) median treatment duration was 17.6 (range: 0.7-130.6) months and the median progression-free survival (PFS) was 22.7 (95% CI, 13.9-37.3) months. In total, 21/76 (27.6%) patients were classified as long-term users because have received vandetanib for more than 48 months, with a median treatment duration of 68.1 (range: 49.1-130.6) months. For long-term vandetanib users, the objective response rate was 85.7%, the median time to best response was 27.8 (11.6.1-110) months and the median duration of response was 70.4 (38.3-127.5) (95% CI 49.5-102.8) months with a median PFS of 73.2 (95% CI, 53.1-105.6) months. Duration of response had a significant negative correlation with patient age at diagnosis (p = 0.03) and was significantly higher in patients that did not have confirmed tumor progression before treatment onset (p = 0.007). After 48 months of vandetanib use, renal failure took place in two patients and heart failure, cholecystitis, acute pancreatitis, posterior encephalopathy, and skin cancer first occurred in one patient, each. CONCLUSIONS: Our findings suggest that a substantial number of patients receiving first-/second-line vandetanib may sustain long clinical benefit and that a younger age at diagnosis and the absence of progression before treatment could be considered as predictors of durable response.
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Antineoplásicos , Carcinoma Neuroendócrino , Pancreatite , Neoplasias da Glândula Tireoide , Doença Aguda , Adulto , Antineoplásicos/efeitos adversos , Carcinoma Neuroendócrino/tratamento farmacológico , Intervalo Livre de Doença , Seguimentos , França , Humanos , Piperidinas , Quinazolinas , Neoplasias da Glândula Tireoide/tratamento farmacológicoRESUMO
Thyroid cancer is the most frequent cancer of the endocrine system. Most patients are treated with thyroidectomy followed by radioiodine therapy. However, in part of the patients, a reduction of the sodium-iodide symporter (NIS) occurs, rendering radioiodine therapy ineffective. Moreover, epithelial-mesenchymal transition (EMT) may occur, leading to more aggressive and invasive features. Herein, we evaluated the effect of the flavonoid quercetin on EMT and NIS expression in BCPAP, a papillary thyroid carcinoma cell line. BCPAP was treated with 100 µM quercetin for 24 h and cell viability, apoptosis, EMT markers and NIS were evaluated. Quercetin decreased cell viability by enhancing apoptosis. The flavonoid also reduced matrix metalloproteinase 9 and increased E-cadherin mRNA levels, inhibiting BCPAP adhesion and migration. Additionally, quercetin increased NIS expression and function. Thus, our results suggest that quercetin could be useful as adjuvant in thyroid cancer therapy, inducing apoptosis, reducing invasion and increasing the efficacy of radioiodine therapy.
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Antígenos CD/genética , Antineoplásicos Fitogênicos/farmacologia , Caderinas/genética , Quercetina/farmacologia , RNA Mensageiro/genética , Simportadores/genética , Glândula Tireoide/efeitos dos fármacos , Antígenos CD/metabolismo , Apoptose/efeitos dos fármacos , Caderinas/agonistas , Caderinas/metabolismo , Adesão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Flavanonas/farmacologia , Regulação Neoplásica da Expressão Gênica , Humanos , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , RNA Mensageiro/agonistas , RNA Mensageiro/metabolismo , Rutina/farmacologia , Transdução de Sinais , Simportadores/agonistas , Simportadores/metabolismo , Glândula Tireoide/metabolismo , Glândula Tireoide/patologiaRESUMO
Breast cancer and thyroid dysfunctions have been associated for decades. Although many studies suggest a biological correlation, the mechanisms linking these two pathologies have not been elucidated. Reactive oxygen species (ROS) can oxidize lipids, proteins, and DNA molecules and may promote tumor initiation. Hence, we aimed at evaluating the mammary redox balance and genomic instability in a model of experimental hypothyroidism. Female Wistar rats were treated with 0.03% methimazole for 7 or 21 days to evaluate ROS generation, antioxidant enzyme activities, and oxidative stress biomarkers, as well as genomic instability. After 7 days, lower catalase, GPX, and DUOX activities were detected in the breast of hypothyroid group compared to the control while the levels of 4-hydroxynonenal (HNE) were higher. In addition, hypothyroid group showed an increase in γH2Ax/H2Ax ratio. Twenty-one days hypothyroid group had increased catalase and SOD activities, without significant differences between groups in the levels of oxidative stress biomarkers and DNA damage. TSH-treated MCF10A cells showed a higher extracellular, intracellular, and mitochondrial ROS production. Additionally, greater DNA damage was observed in these cells, demonstrated by a higher comet tail DNA percentage and increased 53BP1 foci. Finally, we found that TSH treatment was not able to alter cell viability. The Genome Cancer Atlas (TGCA) data showed that high TSHR expression is associated with more invasive breast cancer types. In conclusion, we demonstrate that oxidative stress and DNA damage in breast are early events of experimental hypothyroidism. Moreover, high TSH levels induce oxidative stress and genomic instability in mammary cells.
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Neoplasias da Mama , Hipotireoidismo , Animais , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Biomarcadores , Neoplasias da Mama/genética , Catalase/metabolismo , Dano ao DNA , Feminino , Instabilidade Genômica , Humanos , Estresse Oxidativo , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , TireotropinaRESUMO
Differentiated thyroid carcinoma (DTC) combined with congenital hypothyroidism (CH) is a rare situation, and there is no well-established causal relationship. CH is a common congenital endocrine, while DTC occurring in childhood represents 0.4-3% of all malignancies at this stage of life. The association of CH with DTC could be related to dyshormonogenetic goiter (DHG) or developmental abnormalities. This review will explore the clinical features and the molecular mechanisms potentially associated with the appearance of DTC in CH: sporadic somatic driver mutations, chronic increase of thyroid-stimulating hormone (TSH) levels, higher concentrations of hydrogen peroxide (H2O2), cell division cycle associated 8 (Borelain/CDC8) gene mutations, and in others genes associated with CH - either alone or associated with the mechanisms involved in dyshormonogenesis. There are some pitfalls in the diagnosis of thyroid cancer in patients with CH with nodular goiter, as the proper cytological diagnosis of nodules of patients with dyshormonogenesis might be demanding due to the specific architectural and cytological appearance, which may lead to an erroneous interpretation of malignancy. The purpose of this article is to suggest an analytical framework that embraces the fundamental relationships between the various aspects of CH and CDT. In face of this scenario, the entire genetic and epigenetic context, the complex functioning, and cross talk of cell signaling may determine cellular mechanisms promoting both the maintenance of the differentiated state of the thyroid follicular cell and the disruption of its homeostasis leading to cancer. Whereas, the exact mechanisms for thyroid cancer development in CH remain to be elucidated.
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Hipotireoidismo Congênito , Neoplasias da Glândula Tireoide , Hipotireoidismo Congênito/diagnóstico , Hipotireoidismo Congênito/genética , Hipotireoidismo Congênito/metabolismo , Humanos , Peróxido de Hidrogênio , Mutação , Neoplasias da Glândula Tireoide/genéticaRESUMO
Background: Illness severity in patients infected with COVID-19 is variable. Methods: Here, we conducted an observational, longitudinal, and prospective cohort study to investigate serum thyroid hormone (TH) levels in adult COVID-19 patients, admitted between June and August 2020, and to determine whether they reflect the severity or mortality associated with the disease. Results: Two hundred forty-five patients [median age: 62 (49-75) years] were stratified into non-critical (181) and critically ill (64) groups. Fifty-eight patients (23.6%) were admitted to the intensive care unit, and 41 (16.7%) died. Sixteen (6.5%) exhibited isolated low levels of free triiodothyronine (fT3). fT3 levels were lower in critically ill compared with non-critical patients [fT3: 2.82 (2.46-3.29) pg/mL vs. 3.09 (2.67-3.63) pg/mL, p = 0.007]. Serum reverse triiodothyronine (rT3) was mostly elevated but less so in critically ill compared with non-critical patients [rT3: 0.36 (0.28-0.56) ng/mL vs. 0.51 (0.31-0.67) ng/mL, p = 0.001]. The univariate logistic regression revealed correlation between in-hospital mortality and serum fT3 levels (odds ratio [OR]: 0.47; 95% confidence interval [CI 0.29-0.74]; p = 0.0019), rT3 levels (OR: 0.09; [CI 0.01-0.49]; p = 0.006) and the product fT3 × rT3 (OR: 0.47; [CI 0.28-0.74]; p = 0.0026). Serum thyrotropin, free thyroxine, and fT3/rT3 values were not significantly associated with mortality and severity of the disease. A serum cutoff level of fT3 (≤2.6 pg/mL) and rT3 (≤0.38 ng/mL) was associated with 3.46 and 5.94 OR of mortality, respectively. We found three COVID-19 mortality predictors using the area under the receiver operating characteristic (ROC) curve (AUC score): serum fT3 (AUC = 0.66), rT3 (AUC = 0.64), and the product of serum fT3 × rT3 (AUC = 0.70). Non-thyroidal illness syndrome (fT3 < 2.0 pg/mL) was associated with a 7.05 OR of mortality ([CI 1.78-28.3], p = 0.005) and the product rT3 × fT3 ≤ 1.29 with an 8.08 OR of mortality ([CI 3.14-24.2], p < 0.0001). Conclusions: This prospective study reports data on the largest number of hospitalized moderate-to-severe COVID-19 patients and correlates serum TH levels with illness severity, mortality, and other biomarkers to critical illness. The data revealed the importance of early assessment of thyroid function in hospitalized patients with COVID-19, given the good prognostic value of serum fT3, rT3, and fT3 × rT3 product. Further studies are necessary to confirm these observations.
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COVID-19/mortalidade , SARS-CoV-2 , Hormônios Tireóideos/sangue , Idoso , COVID-19/sangue , Feminino , Hospitalização , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Índice de Gravidade de DoençaRESUMO
The management of radioiodine refractory thyroid cancers (RAIR TC) is challenging for the clinician. Tyrosine kinase inhibitors classically prescribed in this setting can fail due to primary or acquired resistance or the necessity of drug withdrawal because of serious or moderate but chronic and deleterious adverse effects. Thus, the concept of redifferentiation strategy, which involves treating patients with one or more drugs capable of restoring radioiodine sensitivity for RAIR TC, has emerged. The area of redifferentiation strategy leads to the creation of new definitions of RAIR TC including persistent non radioiodine-avid patients and 'true' RAIR TC patients. The latter group presents a restored or increased radioiodine uptake in metastatic lesions but with no radiological response on conventional imaging, that is, progression of a metastatic disease, thus proving that they are 'truly' resistant to the radiation delivered by radioiodine. Unlike these patients, metastatic TC patients with restored radioiodine uptake offer the hope of prolonged remission or even cure of the disease as for radioiodine-avid metastatic TC. Here, we review the different redifferentiation strategies based on the underlying molecular mechanism leading to the sodium iodide symporter (NIS) and radioiodine uptake reinduction, that is, by modulating signaling pathways, NIS transcription, NIS trafficking to the plasma membrane, NIS post-transcriptional regulation, by gene therapy and other potential strategies. We discuss clinical trials and promising preclinical data of potential future targets.
Assuntos
Epigenômica/métodos , Terapia Genética/métodos , Neoplasias da Glândula Tireoide/terapia , Diferenciação Celular , Humanos , Transdução de SinaisRESUMO
DUOX1 is an H2O2-generating enzyme related to a wide range of biological features, such as hormone synthesis, host defense, cellular proliferation, and fertilization. DUOX1 is frequently downregulated in lung and liver cancers, suggesting a tumor suppressor role for this enzyme. Here, we show that DUOX1 expression is decreased in breast cancer cell lines and also in breast cancers when compared to the nontumor counterpart. In order to address the role of DUOX1 in breast cells, we stably knocked down the expression of DUOX1 in nontumor mammary cells (MCF12A) with shRNA. This led to higher cell proliferation rates and decreased migration and adhesion properties, which are typical features for transformed cells. After genotoxic stress induced by doxorubicin, DUOX1-silenced cells showed reduced IL-6 and IL-8 secretion and increased apoptosis levels. Furthermore, the cell proliferation rate was higher in DUOX1-silenced cells after doxorubicin medication in comparison to control cells. In conclusion, we demonstrate here that DUOX1 is silenced in breast cancer, which seems to be involved in breast carcinogenesis.