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OBJECTIVE: To know the impact of a geriatric intervention based on the Comprehensive Geriatric Assessment (CGA) on avoidable admissions in older patients at risk evaluated in the Emergency Department. METHOD: Prospective observational unicenter study. We included patients, from October 1, 2018 to January 31, 2020, over 75 years who were attended at the Emergency Department with a Triage Risk Screening Tool (TRST) score≥2. All patients were evaluated by a geriatrician through the CGA. The reasons for going to the Emergency room were collected and also the main intervention carried out by Geriatrics, whether admission or discharge was indicated and whether the admission was avoidable. We did a cost analysis calculating this by (bed/day×average stay×number of admissions avoided). RESULTS: We included 260 patients, 66% were women and the mean age was 86 years. 73.5% patients had polypharmacy, the mean Charlson index was 2.5 (5.6). 63.3% were independent for walking and 20.8% independent for basic activities of daily living. 59% had cognitive impairment. 91.5% lived at home. The most frequent reason for visiting the Emergency room was decline of general state in 22% and the most frequent intervention carried out by Geriatrics was assistance in the decision making process in 35.4% followed by referral to a preferential outpatient geriatric care circuit in 32.7%. Other interventions carried out by Geriatrics was assistance in clarifying diagnosis (4.2%), assistance in pharmacological adjustment (8.5%), referral to a standard geriatric care pathway (13.1%), telephone follow-up (4.2%) and/or coordination with Social Services for care planning (11.2%). Including all patients, 29.2% required hospital admission and 70.8% were discharged. 40% admissions were avoided, which meant more than 540 thousand euros saved. CONCLUSIONS: A standardized CGA coordinated by Geriatrics in older patients at risk of suffering adverse events in the Emergency room reduces admissions and costs, so it should therefore be established as a recommendation of good clinical practice.
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Sirtuin1 (SIRT1) activity decreases the tuberous sclerosis complex 2 (TSC2) lysine acetylation status, inhibiting the mechanistic target of rapamycin complex 1 (mTORC1) signalling and concomitantly, activating autophagy. This study analyzes the role of TSC2 acetylation levels in its translocation to the lysosome and the mitochondrial turnover in both mouse embryonic fibroblast (MEF) and in mouse insulinoma cells (MIN6) as a model of pancreatic ß cells. Resveratrol (RESV), an activator of SIRT1 activity, promotes TSC2 deacetylation and its translocation to the lysosome, inhibiting mTORC1 activity. An improvement in mitochondrial turnover was also observed in cells treated with RESV, associated with an increase in the fissioned mitochondria, positive autophagic and mitophagic fluxes and an enhancement of mitochondrial biogenesis. This study proves that TSC2 in its deacetylated form is essential for regulating mTORC1 signalling and the maintenance of the mitochondrial quality control, which is involved in the homeostasis of pancreatic beta cells and prevents from several metabolic disorders such as Type 2 Diabetes Mellitus.
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Lisossomos , Mitocôndrias , Proteína 2 do Complexo Esclerose Tuberosa , Animais , Camundongos , Acetilação , Autofagia , Linhagem Celular Tumoral , Fibroblastos/metabolismo , Células Secretoras de Insulina/metabolismo , Lisossomos/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Mitocôndrias/metabolismo , Transporte Proteico , Resveratrol/farmacologia , Transdução de Sinais , Sirtuína 1/metabolismo , Proteína 2 do Complexo Esclerose Tuberosa/metabolismo , Proteína 2 do Complexo Esclerose Tuberosa/genéticaRESUMO
Extracellular vesicles represent a group of structures with the capacity to communicate with different cells and organs. This complex network of interactions can regulate multiple physiological processes in the organism. Very importantly, these processes can be altered during the appearance of different diseases including cancer, metabolic diseases, etc. In addition, these extracellular vesicles can transport different cargoes, altering the initiation of the disease, driving the progression, or even accelerating the pathogenesis. Then, we have explored the implication of these structures in different alterations such as pancreatic cancer, and in different metabolic alterations such as diabetes and its complications and non-alcoholic fatty liver disease. Finally, we have explored in more detail the communication between the liver and the pancreas. In summary, extracellular vesicles represent a very efficient system for the communication among different tissues and permit an efficient system as biomarkers of the disease, as well as being involved in the extracellular-vesicle-mediated transport of molecules, serving as a potential therapy for different diseases.
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BACKGROUND: Immunosuppressed (IS) patients, particularly solid organ transplant recipients and those on immunosuppressive therapy, face a higher incidence and recurrence of nonmelanoma skin cancers (NMSC), including basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). Mohs micrographic surgery (MMS) is the preferred treatment for high-risk NMSC due to its high cure rate and margin examination capabilities. However, IS patients may experience more complications, such as surgical site infections, and a greater risk of recurrence, making their outcomes a subject of interest. OBJECTIVES: This study aimed to compare IS and immunocompetent (IC) patients undergoing MMS for NMSC in terms of baseline characteristics, intra- and post-surgical complications, and postoperative recurrence rates. METHODS: The study utilized data from the REGESMOHS registry, a 7-year prospective cohort study in Spain. It included 5226 patients, categorizing them into IC (5069) and IS (157) groups. IS patients included solid organ transplant recipients, those on immunosuppressive treatments, individuals with haematological tumours and HIV-positive patients. Patient data, tumour characteristics, surgical details and outcomes were collected and analysed. RESULTS: IS patients demonstrated a higher proportion of SCC, multiple synchronous tumours and tumours invading deeper structures. Complex closures, unfinished MMS and more surgical sections were observed in the IS group. Although intra-operative morbidity was higher among IS patients, this difference became non-significant when adjusted for other variables such as year of surgery, antiplatelet/anticoagulant treatment or type of closure. Importantly, IS patients had a substantially higher recurrence rate (IRR 2.79) compared to IC patients. CONCLUSIONS: This study suggests that IS patients may be at a higher risk of development of AE such as bleeding or tumour necrosis and are at a higher risk of tumour recurrence. Close follow-up and consideration of the specific characteristics of NMSC in IS patients are crucial. Further research with extended follow-up is needed to better understand the long-term outcomes for this patient group.
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Diabetes is a very complex disease which is characterized by the appearance of insulin resistance that is primarily compensated by an increase in pancreatic beta cell mass, generating hyperinsulinemia. After time, pancreatic beta cells die by apoptosis appearing in the second phase of the disease, and characterized by hypoinsulinemia. There are multiple conditions that can alter pancreatic beta cell homeostasis and viability, being the most relevant ones; ER stress, cytotoxicity by amylin, mTORC1 hyperactivity, oxidative stress, mitochondrial dysfunction, inflammation and alterations in autophagy/mitophagy flux. In addition, the possible effects that different polyphenols could exert in the modulation of these mechanisms and regulating pancreatic beta cell viability are analyzed. It is necessary a profound analysis and understanding of all the possible mechanisms involved in the control and maintenance of pancreatic beta cell viability to develop more accurate and target treatments for controlling beta cell homeostasis and preventing or even reversing type 2 diabetes mellitus.
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Diabetes Mellitus Tipo 2 , Resistência à Insulina , Células Secretoras de Insulina , Humanos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Polifenóis/farmacologia , Polipeptídeo Amiloide das Ilhotas PancreáticasRESUMO
Sonidegib is a Hedgehog signalling pathway inhibitor approved for use in patients with advanced basal cell carcinoma (BCC) not eligible for surgery or radiotherapy. This report describes clinical experience with sonidegib in two patients with locally advanced BCC (one with a tumour adjacent to the right eye and the other with a tumour associated with the left ear) and in one patient with Gorlin syndrome. Two of the patients had recurrent and intractable tumours. Treatment with sonidegib 200 mg/day led to remission in both patients with locally advanced BCC within 7 months and to a reduction in the size and number of lesions after 4 months in the patient with Gorlin syndrome. Adverse effects reported in these patients were cramps, alopecia, ageusia and weight loss, all of which were mild and consistent with the known toxicity profile for sonidegib. Sonidegib has an important role to play in the effective treatment of challenging cases of advanced BCC. In parallel, a need remains to improve management protocols for patients with advanced BCC, particularly through earlier intervention and a multidisciplinary team approach.
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BACKGROUND: Dermatofibrosarcoma protuberans (DFSP) is an invasive skin tumor traditionally associated with very high recurrence rates when treated with conventional surgery (CS). OBJECTIVE: To calculate the minimum margin that would have been required to achieve complete tumor clearance with hypothetical CS. To analyze DFSP characteristics and Mohs micrographic surgery (MMS) effectiveness in treatment of this tumor. MATERIALS AND METHODS: Minimum margin was calculated by measuring the largest distance from the visible edge of the tumor to the edge of the surgical defect. Tumor variables (age, sex, size, time since onset, and location) were correlated with surgical variables (number of stages and minimum margin). RESULTS: We studied 222 cases of DFSP treated with MMS. A mean of 1.47 MMS stages and a mean minimum margin of 1.23 cm were required to achieve tumor clearance. Tumors on the head and neck required significantly more stages and a significantly wider margin. Tumor size was positively correlated with time to diagnosis, age, and number of MMS stages. CONCLUSION: Tumors located on the head and neck have greater subclinical extension. Tumor size was also a predictor of surgical difficulty, but time to diagnosis was not.
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Dermatofibrossarcoma/cirurgia , Neoplasias de Cabeça e Pescoço/cirurgia , Cirurgia de Mohs/métodos , Recidiva Local de Neoplasia/epidemiologia , Neoplasias Cutâneas/cirurgia , Adolescente , Adulto , Dermatofibrossarcoma/diagnóstico , Dermatofibrossarcoma/patologia , Feminino , Seguimentos , Neoplasias de Cabeça e Pescoço/diagnóstico , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Estudos Longitudinais , Masculino , Margens de Excisão , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/prevenção & controle , Pele/patologia , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/patologia , Resultado do Tratamento , Adulto JovemAssuntos
COVID-19 , Lesão Pulmonar , Serviço Hospitalar de Emergência , Humanos , SARS-CoV-2 , UltrassonografiaRESUMO
Sambucus nigra flowers (elderflower) have been widely used in traditional medicine for the relief of early symptoms of common cold. Its chemical composition mainly consists of polyphenolic compounds such as flavonoids, hydroxycinnamic acids, and triterpenes. Although the antioxidant properties of polyphenols are well known, the aim of this study is to assess the antioxidant and protective potentials of Sambucus nigra flowers in the human neuroblastoma (SH-SY5Y) cell line using different in vitro approaches. The antioxidant capacity is first evaluated by the oxygen radical absorbance capacity (ORAC) and the free radical scavenging activity (DPPH) methods. Cell viability is assessed by the crystal violet method; furthermore, the intracellular ROS formation (DCFH-DA method) is determined, together with the effect on the cell antioxidant defenses: reduced glutathione (GSH) and antioxidant enzyme activities (GPx, GR). On the other hand, mTORC1 hyperactivation and autophagy blockage have been associated with an increase in the formation of protein aggregates, this promoting the transference and expansion of neurodegenerative diseases. Then, the ability of Sambucus nigra flowers in the regulation of mTORC1 signaling activity and the reduction in oxidative stress through the activation of autophagy/mitophagy flux is also examined. In this regard, search for different molecules with a potential inhibitory effect on mTORC1 activation could have multiple positive effects either in the molecular pathogenic events and/or in the progression of several diseases including neurodegenerative ones.
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Técnicas de Cultura de Células , Degeneração Neural/tratamento farmacológico , Sambucus nigra/química , Antioxidantes/farmacologia , Autofagia/efeitos dos fármacos , Compostos de Bifenilo/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Flores/química , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Redutase/metabolismo , Humanos , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Degeneração Neural/patologia , Picratos/química , Extratos Vegetais/farmacologia , Polifenóis/farmacologia , Substâncias Protetoras/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacosRESUMO
BACKGROUND: Small series of ultrasound findings in dermatofibrosarcoma protuberans (DFSP) have been published, but the usefulness of this technique as a preoperative planning tool for tumor resection has not been studied. MATERIALS AND METHODS: We retrospectively reviewed patients with DFSP at our hospital that underwent ultrasound examination. Depth of invasion was evaluated by ultrasound and histopathology. Accuracy of ultrasound for assessing depth of tumor invasion was estimated. RESULTS: Thirty histopathologically confirmed DFSPs were studied. Classic finger-like projections were observed in 73.3% of cases. A posterior hyperechoic area extending deep into the subcutaneous tissue correlated with the honeycomb DFSP pattern and was observed in 53.3% of patients. Concordance between ultrasound and histopathologic depth measurements was excellent. Lateral tumor extension and Doppler activity were not evaluated in our series. CONCLUSION: Ultrasound showed excellent prediction of depth of invasion. Further studies are required to define the usefulness of ultrasound for determining lateral tumor extension.
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Dermatofibrossarcoma , Neoplasias Cutâneas , Dermatofibrossarcoma/diagnóstico por imagem , Humanos , Estudos Retrospectivos , Neoplasias Cutâneas/diagnóstico por imagem , Tela Subcutânea , UltrassonografiaRESUMO
Polyphenols represent a group of secondary metabolites of plants which have been analyzed as potent regulators of multiple biological processes, including cell proliferation, apoptosis, and autophagy, among others. These natural compounds exhibit beneficial effects and protection against inflammation, oxidative stress, and related injuries including metabolic diseases, such as cardiovascular damage, obesity and diabetes, and neurodegeneration. This review aims to summarize the mechanisms of action of polyphenols in relation to the activation of autophagy, stimulation of mitochondrial function and antioxidant defenses, attenuation of oxidative stress, and reduction in cell apoptosis, which may be responsible of the health promoting properties of these compounds.
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BACKGROUND: Relatively little is known about the true aggressive potential of pleomorphic dermal sarcoma (PDS) or optimal management strategies. OBJECTIVE: To describe the outcomes of 16 cases of PDS treated at our hospital (14 with modified Mohs micrographic surgery [M-MMS] and two with conventional surgery) and establish an adequate plan for management. MATERIALS & METHODS: We reviewed 16 PDS cases treated at our hospital between October 2007 and June 2019 and compared our results with the available evidence. RESULTS: In total, 69% of cases had recurred after initial conventional surgery, M-MMS led to local disease control in 83% of cases, and 19% of patients developed metastasis. Combining all published PDS cases with ours, we calculated an overall metastasis rate of 12%, and an overall recurrence rate of 35% after conventional surgery and 17% after M-MMS. CONCLUSION: PDS is more aggressive than previously estimated, with an overall metastatic rate of 12%. Despite high recurrence rates with previous conventional surgery (69%), M-MMS achieved a good rate of local disease control (83%). Given the potential aggressivity of PDS and the importance of clear surgical margins, M-MMS appears to be more adequate than conventional excision. Staging studies and close monitoring are warranted in PDS patients, for which we propose a management algorithm.
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Sarcoma/patologia , Sarcoma/cirurgia , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/cirurgia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Margens de Excisão , Cirurgia de Mohs , Metástase Neoplásica , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Prognóstico , Estudos RetrospectivosRESUMO
Basal cell carcinoma (BCC) represents the most commonly diagnosed human cancer among persons of European ancestry with etiology mainly attributed to sun-exposure. In this study we investigated mutations in coding and flanking regions of PTCH1 and TP53 and noncoding alterations in the TERT and DPH3 promoters in 191 BCC tumors. In addition, we measured CpG methylation within the TERT hypermethylated oncological region (THOR) and transcription levels of the reverse transcriptase subunit. We observed mutations in PTCH1 in 58.6% and TP53 in 31.4% of the tumors. Noncoding mutations in TERT and DPH3 promoters were detected in 59.2% and 38.2% of the tumors, respectively. We observed a statistically significant co-occurrence of mutations at the four investigated loci. While PTCH1 mutations tended to associate with decreased patient age at diagnosis; TP53 mutations were associated with light skin color and increased number of nevi; TERT and DPH3 promoter with history of cutaneous neoplasms in BCC patients. Increased reverse transcriptase subunit expression was observed in tumors with TERT promoter mutations and not with THOR methylation. Our study signifies, in addition to the protein altering mutations in the PTCH1 and TP53 genes, the importance of noncoding mutations in BCC, particularly functional alterations in the TERT promoter.
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Biomarcadores Tumorais , Carcinoma Basocelular/genética , Mutação , Fases de Leitura Aberta , Regiões não Traduzidas , Metilação de DNA , Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Humanos , Regiões Promotoras Genéticas , Neoplasias Cutâneas/genéticaRESUMO
Energy sensing is indispensable to balance anabolic and catabolic processes for the maintenance of cell viability. Pancreatic ß cells are especially relevant because of their involvement in the coordination of insulin secretion when glucose concentration arises in the local milieu. In this work, we uncover the increased susceptibility of pancreatic ß cells to cell death in response to different energy stressors. Upon glucose decline, from 25 to 5 mM, caused by stimulation with either 2-deoxyglucose or metformin, only pancreatic ß cells showed an increase in cell death. Very interestingly, when we transfected either mouse insulinoma cell or human embryo kidney cells with a phospho-mutant form of B cell lymphoma 2 associated agonist of cell death at serine 155 (BAD S155D), an increase in the pro-survival factor B cell lymphoma 2 was detected in pancreatic ß cells and not in human embryonic kidney cells in the presence of the energetic stressors. This data suggests that the protective capacity of this mutant form is only present in cells that present glucokinase. In contrast, upon hyperactivation of mechanistic target of rapamycin complex 1 signaling by knocking-down tuberous sclerosis complex protein, we observed increased susceptibility to cell death in response to energy stress in both pancreatic and non-pancreatic ß cells. Therefore, mechanistic target of rapamycin complex 1 signaling presents a dual effect on cell viability. On the one hand, a chronic inhibition of mechanistic target of rapamycin complex 1 activity in response to the energy status is deleterious for pancreatic ß cells, being attenuated by the overexpression of B cell lymphoma 2 associated agonist of cell death S155D. On the other hand, mechanistic target of rapamycin complex 1 hyperactivity provokes a susceptibility to energetic stress-induced cell death. Taken together, these results may open potential implications for the use of glucokinase activators or mechanistic target of rapamycin complex 1 modulators for the maintenance of pancreatic ß cells for longer periods of time avoiding its loss in different pathologies such as type 2 diabetes mellitus.
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BACKGROUND: Anterior spinal artery syndrome, usually resulting in flaccid paraplegia, is a rare but disastrous complication that can occur after surgery of aortic aneurysms and aortic dissections. Spinal cord infarct as the initial clinical presentation of aortic dissection is a very rare finding. CASE REPORT: A 42-year-old male patient who comes to the emergency department due to severe chest pain associated with presyncope and paraplegia of the lower limbs in the context of type A aortic dissection. CONCLUSIONS: Recognizing this atypical clinical presentation of aortic dissection and knowing how to approach it is critical for an early diagnosis and to minimize the risk of spinal cord ischemia during surgery.
ANTECEDENTES: La lesión de la médula espinal, generalmente resultante en paraplejia flácida, es una complicación rara, pero desastrosa, que puede ocurrir tras intervenciones quirúrgicas de aneurismas o disecciones de aorta. La presentación clínica inicial de una disección de aorta como un síndrome de la arteria espinal anterior es un hallazgo muy infrecuente. CASO CLÍNICO: Varón de 42 años que acude al servicio de urgencias hospitalario por dolor torácico intenso asociado a cuadro presincopal y paraplejia de miembros inferiores en el contexto de una disección de aorta tipo A. CONCLUSIONES: Reconocer esta forma de presentación clínica y saber cómo realizar un abordaje adecuado es fundamental para el diagnóstico precoz y para minimizar el riesgo quirúrgico de presentar isquemia medular.
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Síndrome da Artéria Espinal Anterior/etiologia , Aneurisma da Aorta Abdominal/complicações , Aneurisma da Aorta Torácica/complicações , Dissecção Aórtica/complicações , Paraplegia/etiologia , Adulto , Dissecção Aórtica/cirurgia , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Abdominal/cirurgia , Aneurisma da Aorta Torácica/diagnóstico por imagem , Aneurisma da Aorta Torácica/cirurgia , Dor no Peito/etiologia , Dilatação Patológica/diagnóstico por imagem , Dilatação Patológica/cirurgia , Humanos , Imageamento por Ressonância Magnética , Masculino , Artéria Renal/diagnóstico por imagem , Medula Espinal/diagnóstico por imagem , Coluna Vertebral/diagnóstico por imagem , Tomografia Computadorizada por Raios XRESUMO
BACKGROUND: The plaque variant of trichoblastoma has been described as a solitary tumor with diffuse infiltration of the lower dermis and hypodermis, with poorly defined borders. Herein, we report a new variant of multiple centrofacial trichoblastoma. OBJECT: To describe clinical and pathological features of a new multiple kind of plaque variant of centrofacial trichoblastoma. METHODS: Case series of patients with a multiple-plaque variant of centrofacial trichoblastoma treated in our department between 2005 and 2017. We identified eight patients with the centrofacial plaque variant of trichoblastoma treated in our department from 2005 to 2017. RESULTS: The final study sample comprised 13 trichoblastomas from four patients. All patients also developed at least one basal cell carcinoma. Mohs surgery was the method of treatment in the majority of the cases of trichoblastoma and in all the cases of basal cell carcinoma. We needed between 2 and 6 stages to obtain free margins in our cases of facial plaque trichoblastomas treated by Mohs surgery. CONCLUSION: To the best of our knowledge, a multiple-plaque variant of trichoblastoma has not been described in the literature. We suggest a genetic origin of this variant of trichoblastoma and describe its remarkable infiltrative nature, with poorly defined surgical margins.
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Doenças do Cabelo/patologia , Folículo Piloso/patologia , Neoplasias Cutâneas/patologia , Idoso , Face/patologia , Feminino , Doenças do Cabelo/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Cirurgia de Mohs , Neoplasias Cutâneas/cirurgiaRESUMO
Human islet amyloid polypeptide (hIAPP), or amylin, has the tendency to aggregate into insoluble amyloid fibrils, a typical feature of islets from type 2 diabetes individuals. Thus, we investigated comparatively the impact of hIAPP on key pathways involved in pancreatic beta survival. INS1E-hIAPP cells present a hyperactivation of MTORC1 and an inhibition of autophagy signaling, those cells showing an increase in cell size. Resveratrol, a MTORC1 inhibitor, can reverse TSC2 degradation that occurs in INS1E-hIAPP cells and diminished MTORC1 hyperactivation with concomitant autophagy stimulation. At the same time, a blockade in mitophagy was found in INS1E-hIAPP cells, as compared with control or INS1E-rIAPP cells. Consistently, human amylin overexpression generates a basal induction of nitrotyrosine levels and polyubiquitinated aggregates. Failure of the protein degradation machinery finally results in an accumulation of damaged and fissioned mitochondria, ROS production, and increased susceptibility to endoplasmic reticulum (ER)-stress-induced apoptosis. Overall, hIAPP overexpression in INS1E cells induced MTORC1 activation and mitophagy inhibition, favoring a pro-fission scenario of damaged mitochondria, these cells turn out to be more susceptible to the ER-stress-induced apoptosis and malfunction.
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Células Secretoras de Insulina/metabolismo , Polipeptídeo Amiloide das Ilhotas Pancreáticas/metabolismo , Mitocôndrias/metabolismo , Dinâmica Mitocondrial , Mitofagia , Animais , Apoptose , Linhagem Celular Tumoral , Estresse do Retículo Endoplasmático , Humanos , Células Secretoras de Insulina/ultraestrutura , Polipeptídeo Amiloide das Ilhotas Pancreáticas/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Mitocôndrias/ultraestrutura , Proteólise , Ratos , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Proteína 2 do Complexo Esclerose Tuberosa/metabolismo , Tirosina/análogos & derivados , Tirosina/metabolismo , Ubiquitinação , Regulação para CimaRESUMO
Cutaneous angiosarcoma (AS) is an uncommon, aggressive sarcoma whose incidence is rising because of the increasing use of radiation therapy, especially in breast cancer. The few studies on the relevance of prognostic factors, such as MYC status in cutaneous AS, have reported inconclusive findings, with some authors reporting MYC amplification only in postirradiation and lymphedema-associated AS and others reporting evidence of MYC amplification in idiopathic AS. We analyzed 17 cases of cutaneous AS (6 idiopathic AS, 10 postirradiation AS, and 1 lymphedema-associated AS) treated at our institute between 2000 and 2015. Follow-up data were available in all cases. We compared the presence/absence of MYC amplification by fluorescence in situ hybridization (FISH) and immunohistochemical (IHC) MYC overexpression in the different AS subtypes. We also investigated potential associations between MYC amplification and prognosis. MYC amplification was observed by FISH in 6 of 14 informative cases. The positive cases were all secondary AS (5 postirradiation AS and 1 lymphedema-associated AS). IHC detected MYC overexpression in 8 of 15 informative cases (7 secondary AS and 1 idiopathic AS). In conclusion, MYC amplification and MYC overexpression were detected almost exclusively in secondary AS. No associations were found between MYC amplification/overexpression and prognosis. We found MYC amplification or overexpression in a similar proportion of the patients who died and who were still alive at the end of the study. In the group of 9 patients who died, MYC was detected by FISH in 4 cases and by IHC in 5. The corresponding figures in the group of 6 patients still alive were 2 by FISH and 3 by IHC.
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Hemangiossarcoma/genética , Neoplasias Induzidas por Radiação/genética , Proteínas Proto-Oncogênicas c-myc/genética , Neoplasias Cutâneas/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Amplificação de Genes , Hemangiossarcoma/mortalidade , Hemangiossarcoma/patologia , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Masculino , Pessoa de Meia-Idade , Neoplasias Cutâneas/mortalidade , Neoplasias Cutâneas/patologiaRESUMO
Mechanistic target of rapamycin complex 1 (MTORC1) is a critical negative regulator of general autophagy. We hypothesized that MTORC1 may specifically regulate autophagic clearance of damaged mitochondria. To test this, we used cells lacking tuberous sclerosis complex 2 (TSC2-/- cells), which show constitutive MTORC1 activation. TSC2-/- cells show MTORC1-dependent impaired autophagic flux after chemical uncoupling of mitochondria, increased mitochondrial-protein aging, and accumulation of p62/SQSTM1-positive mitochondria. Mitochondrial autophagy (mitophagy) was also deficient in cells lacking TSC2, associated with altered expression of PTEN-induced putative kinase 1 (PINK1) and PARK2 translocation to uncoupled mitochondria, all of which were recovered by MTORC1 inhibition or expression of constitutively active forkhead box protein O1 (FoxO1). These data prove the necessity of intact MTORC1 signaling to regulate two synergistic processes required for clearance of damaged mitochondria: (i) general autophagy initiation and (ii) PINK1/PARK2-mediated selective targeting of uncoupled mitochondria to the autophagic machinery.