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The causes and consequences of abnormal biogenesis of extracellular vesicles (EVs) are not yet well understood in malignancies, including in breast cancers (BCs). Given the hormonal signaling dependence of estrogen receptor-positive (ER+) BC, we hypothesized that 17ß-estradiol (estrogen) might influence EV production and microRNA (miRNA) loading. We report that physiological doses of 17ß-estradiol promote EV secretion specifically from ER+ BC cells via inhibition of miR-149-5p, hindering its regulatory activity on SP1, a transcription factor that regulates the EV biogenesis factor nSMase2. Additionally, miR-149-5p downregulation promotes hnRNPA1 expression, responsible for the loading of let-7's miRNAs into EVs. In multiple patient cohorts, we observed increased levels of let-7a-5p and let-7d-5p in EVs derived from the blood of premenopausal ER+ BC patients, and elevated EV levels in patients with high BMI, both conditions associated with higher levels of 17ß-estradiol. In brief, we identified a unique estrogen-driven mechanism by which ER+ BC cells eliminate tumor suppressor miRNAs in EVs, with effects on modulating tumor-associated macrophages in the microenvironment.
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Neoplasias da Mama , Vesículas Extracelulares , MicroRNAs , Humanos , Feminino , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias da Mama/patologia , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Estradiol/farmacologia , Estradiol/metabolismo , Estrogênios/metabolismo , Vesículas Extracelulares/genética , Vesículas Extracelulares/metabolismo , Microambiente TumoralRESUMO
BACKGROUND & AIMS: Chromosomal instability (CIN) is a carcinogenesis event that promotes metastasis and resistance to therapy by unclear mechanisms. Expression of the colon cancer-associated transcript 2 gene (CCAT2), which encodes a long noncoding RNA (lncRNA), associates with CIN, but little is known about how CCAT2 lncRNA regulates this cancer enabling characteristic. METHODS: We performed cytogenetic analysis of colorectal cancer (CRC) cell lines (HCT116, KM12C/SM, and HT29) overexpressing CCAT2 and colon organoids from C57BL/6N mice with the CCAT2 transgene and without (controls). CRC cells were also analyzed by immunofluorescence microscopy, γ-H2AX, and senescence assays. CCAT2 transgene and control mice were given azoxymethane and dextran sulfate sodium to induce colon tumors. We performed gene expression array and mass spectrometry to detect downstream targets of CCAT2 lncRNA. We characterized interactions between CCAT2 with downstream proteins using MS2 pull-down, RNA immunoprecipitation, and selective 2'-hydroxyl acylation analyzed by primer extension analyses. Downstream proteins were overexpressed in CRC cells and analyzed for CIN. Gene expression levels were measured in CRC and non-tumor tissues from 5 cohorts, comprising more than 900 patients. RESULTS: High expression of CCAT2 induced CIN in CRC cell lines and increased resistance to 5-fluorouracil and oxaliplatin. Mice that expressed the CCAT2 transgene developed chromosome abnormalities, and colon organoids derived from crypt cells of these mice had a higher percentage of chromosome abnormalities compared with organoids from control mice. The transgenic mice given azoxymethane and dextran sulfate sodium developed more and larger colon polyps than control mice given these agents. Microarray analysis and mass spectrometry indicated that expression of CCAT2 increased expression of genes involved in ribosome biogenesis and protein synthesis. CCAT2 lncRNA interacted directly with and stabilized BOP1 ribosomal biogenesis factor (BOP1). CCAT2 also increased expression of MYC, which activated expression of BOP1. Overexpression of BOP1 in CRC cell lines resulted in chromosomal missegregation errors, and increased colony formation, and invasiveness, whereas BOP1 knockdown reduced viability. BOP1 promoted CIN by increasing the active form of aurora kinase B, which regulates chromosomal segregation. BOP1 was overexpressed in polyp tissues from CCAT2 transgenic mice compared with healthy tissue. CCAT2 lncRNA and BOP1 mRNA or protein were all increased in microsatellite stable tumors (characterized by CIN), but not in tumors with microsatellite instability compared with nontumor tissues. Increased levels of CCAT2 lncRNA and BOP1 mRNA correlated with each other and with shorter survival times of patients. CONCLUSIONS: We found that overexpression of CCAT2 in colon cells promotes CIN and carcinogenesis by stabilizing and inducing expression of BOP1 an activator of aurora kinase B. Strategies to target this pathway might be developed for treatment of patients with microsatellite stable colorectal tumors.
Assuntos
Instabilidade Cromossômica , Neoplasias Colorretais/genética , Neoplasias Experimentais/genética , RNA Longo não Codificante/metabolismo , Proteínas de Ligação a RNA/genética , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Aurora Quinase B/metabolismo , Azoximetano/toxicidade , Carcinogênese/genética , Linhagem Celular Tumoral , Colo/citologia , Colo/patologia , Neoplasias Colorretais/induzido quimicamente , Neoplasias Colorretais/patologia , Análise Citogenética , Dextranos/toxicidade , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Mucosa Intestinal/citologia , Mucosa Intestinal/patologia , Masculino , Camundongos , Camundongos Transgênicos , Neoplasias Experimentais/induzido quimicamente , Neoplasias Experimentais/patologia , Organoides , Cultura Primária de Células , Proteínas Proto-Oncogênicas c-myc/metabolismo , RNA Longo não Codificante/genética , Proteínas de Ligação a RNA/metabolismo , Transdução de Sinais/genéticaRESUMO
Glioblastoma is a highly aggressive brain tumour that creates an immunosuppressive microenvironment. Microglia, the brain's resident immune cells, play a crucial role in this environment. Glioblastoma cells can reprogramme microglia to create a supportive niche that promotes tumour growth. However, the mechanisms controlling the acquisition of a transcriptome associated with a tumour-supportive microglial reactive state are not fully understood. In this study, we investigated changes in the transcriptional profile of BV2 microglia exposed to C6 glioma cells. RNA-sequencing analysis revealed a significant upregulation of microglial inhibitor of DNA binding 1 (Id1) and Id2, helix-loop-helix negative transcription regulatory factors. The concomitant regulation of microglial ETS proto-oncogene 2, transcription factor (ETS2)-target genes, i.e., Dusp6, Fli1, Jun, Hmox1, and Stab1, led us to hypothesize that ETS2 could be regulated by ID proteins. In fact, ID2-ETS2 protein interactions increased in microglia exposed to glioma cells. In addition, perturbation of the ID2-ETS2 transcriptional axis influenced the acquisition of a microglial tumour-supportive phenotype. ID2 and ETS2 genes were found to be expressed by the tumour-associated microglia isolated from human glioblastoma tumour biopsies. Furthermore, ID2 and ETS2 gene expressions exhibited inverse prognostic values in patients with glioma in cohorts from The Cancer Genome Atlas. Collectively, our findings indicate that the regulation of ETS2 by ID2 plays a role in the transcriptional regulation of microglia in response to stimuli originating from glioblastoma cells, information that could lead to developing therapeutic strategies to manipulate microglial tumour-trophic functions.
Assuntos
Glioma , Proteína 2 Inibidora de Diferenciação , Microglia , Proto-Oncogene Mas , Proteína Proto-Oncogênica c-ets-2 , Proteína 2 Inibidora de Diferenciação/metabolismo , Proteína 2 Inibidora de Diferenciação/genética , Microglia/metabolismo , Microglia/patologia , Proteína Proto-Oncogênica c-ets-2/metabolismo , Proteína Proto-Oncogênica c-ets-2/genética , Humanos , Glioma/genética , Glioma/patologia , Glioma/metabolismo , Animais , Linhagem Celular Tumoral , Fenótipo , Regulação Neoplásica da Expressão Gênica , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/metabolismo , Transcrição Gênica , Ratos , Glioblastoma/genética , Glioblastoma/patologia , Glioblastoma/metabolismoRESUMO
Thrombotic thrombocytopenic purpura (TTP) is a low prevalence disease characterized by severe deficiency of the enzyme ADAMTS13, leading to the development of thrombotic microangiopathy (TMA) and often resulting in severe organ disfunction. TTP is an extremely serious condition and, therefore, timely and appropriate treatment is critical to prevent life-threatening complications.Over the past 25 years, significant advances in the understanding of the pathophysiology of immune TTP have led to the development of readily available techniques for measuring ADAMTS13 levels, as well as new drugs that are particularly effective in the acute phase and in preventing relapses. These developments have improved the course of the disease.Given the complexity of the disease and its various clinical and laboratory manifestations, early diagnosis and treatment can be challenging.To address this challenge, a group of experienced professionals from the Catalan TTP group have developed this consensus statement to standardize terminology, diagnosis, treatment and follow up for immune TTP, based on currently available scientific evidence in the field. This guidance document aims to provide healthcare professionals with a comprehensive tool to make more accurate and timely diagnosis of TTP and improve patient outcomes.
Assuntos
Púrpura Trombocitopênica Idiopática , Púrpura Trombocitopênica Trombótica , Humanos , Púrpura Trombocitopênica Trombótica/diagnóstico , Púrpura Trombocitopênica Trombótica/terapia , Púrpura Trombocitopênica Trombótica/etiologia , Proteína ADAMTS13 , Consenso , Fator de von Willebrand , RecidivaRESUMO
Downregulation of MHC class I (MHCI) molecules on tumor cells is recognized as a resistance mechanism of cancer immunotherapy. Given that MHCI molecules are potent regulators of immune responses, we postulated that the expression of MHCI by tumor cells influences systemic immune responses. Accordingly, mice-bearing MHCI-deficient tumor cells showed reduced tumor-associated extramedullary myelopoiesis in the spleen. Depletion of natural killer (NK) cells abrogated these differences, suggesting an integral role of immune-regulatory NK cells during tumor progression. Cytokine-profiling revealed an upregulation of TNF-α by NK cells in tumors and spleen in mice-bearing MHCI expressing tumors, and inhibition of TNF-α enhanced host myelopoiesis in mice receiving adoptive transfer of tumor-experienced NK cells. Our study highlights a critical role of NK cells beyond its identity as a killer lymphocyte and more importantly, the potential host responses to a localized tumor as determined by its MHCI expression.
Assuntos
Mielopoese , Neoplasias , Camundongos , Animais , Fator de Necrose Tumoral alfa , Células Matadoras Naturais , Antígenos de Histocompatibilidade Classe IRESUMO
As one of the most recently (re)discovered types of non-coding RNAs (ncRNA), circular RNAs (circRNAs) differentiate from other ncRNAs by a specific biogenesis, high stability, and distinct functions. The biogenesis of circRNAs can be categorized into three mechanisms that permit the back-splicing reaction: exon-skipping, pairing of neighboring introns, and dimerization of RNA-binding proteins. Regarding their stability, circRNAs have no free ends, specific to linear RNA molecules, prompting a longer half-life and resistance to exonuclease-mediated activity by RNase R, bypassing the common RNA turnover process. Regarding their functions, circular transcripts can be categorized into four broad roles: miRNA sponging, protein binding, regulation of transcription, and coding for proteins and peptides. Female reproductive system (including mainly ovarian, corpus, and cervix uteri cancers) and breast cancers are the primary causes of death in women worldwide, accounting for over 1,212,772 deaths in 2018. We consider that a better understanding of the molecular pathophysiology through the study of coding and non-coding RNA regulators could improve the diagnosis and therapeutics of these cancers. Developments in the field of circRNA in regard to breast or gynecological cancers are recent, with most circRNA-related discoveries having been made in the last 2 years. Therefore, in this review we summarize the newly detected roles of circRNAs in female reproductive system (cervical cancer, ovarian cancer, and endometrial cancer) and breast cancers. We argue that circRNAs can become essential elements of the diagnostic and therapeutic tools for female reproductive system cancers in the future.
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One of the major challenges in oncology is drug resistance, which triggers relapse and shortens patients' survival. In order to promote drug desensitization, cancer cells require the establishment of an ideal tumor microenvironment that accomplishes specific conditions. To achieve this objective, cellular communication is a key factor. Classically, cells were believed to restrictively communicate by ligand-receptor binding, physical cell-to-cell interactions and synapses. Nevertheless, the crosstalk between tumor cells and stroma cells has also been recently reported to be mediated through exosomes, the smallest extracellular vesicles, which transport a plethora of functionally active molecules, such as: proteins, lipids, messenger RNA, DNA, microRNA or long non-coding RNA (lncRNAs). LncRNAs are RNA molecules greater than 200 base pairs that are deregulated in cancer and other diseases. Exosomal lncRNAs are highly stable and can be found in several body fluids, being considered potential biomarkers for tumor liquid biopsy. Exosomal lncRNAs promote angiogenesis, cell proliferation and drug resistance. The role of exosomal lncRNAs in drug resistance affects the main treatment strategies in oncology: chemotherapy, targeted therapy, hormone therapy and immunotherapy. Overall, knowing the molecular mechanisms by which exosomal lncRNA induce pharmacologic resistance could improve further drug development and identify drug resistance biomarkers.
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INTRODUCCIÓ: Els abscessos parafaringi I retrofaringi són infeccions profundes del coll que solen associar-se a l'antecedent d'infecció de vies respiratòries altes. Ocasionalment poden ser causats per traumatismes com els que comporten algunes manipulacions mèdiques, per exemple, la col·locació de mascareta laríngia, molt utilitzada en cirurgia pediàtrica. CAS CLÍNIC: Es presenta el cas d'una nena de 6 anys amb torticoli de 8 dies d'evolució I febre de 24 hores, sense cap altra simptomatologia. La pacient havia estat intervinguda quirúrgicament sota anestèsia general amb col·locació de mascareta laríngia 36 hores abans de l'inici del quadre, sense incidències. En l'exploració, destaca una contractura cervical bilateral amb flexió del cap a la dreta, I a l'analítica es troba leucocitosi amb predomini de neutròfils I augment de la proteïna C reactiva. Es fa una ressonància magnètica cervical en què s'observa un abscés d'extensió parafaríngia I retrofaríngia, I s'indica una punció percutània ecoguiada de l'àrea abscessificada, que resulta positiva per a S. pyogenes. S'ingressa la pacient amb antibioteràpia endovenosa I s'aconsegueix la millora clínica I radiològica de l'abscés. COMENTARIS: Els abscessos cervicals profunds s'han de considerar davant de simptomatologia obstructiva I inflamatòria de la via aèria I el tracte digestiu superior, I símptomes locals o dolor al moviment cervical. El diagnòstic es basa en les troballes radiològiques, analítiques I microbiològiques, I cal instaurar antibioteràpia endovenosa empírica amb cobertura per a estafilococs, estreptococs I anaerobis. Tot I que aquests abscessos en la majoria de casos són secundaris a l'extensió d'infeccions del tracte respiratori superior, hi ha altres causes que cal considerar
INTRODUCCIÓN: Los abscesos retrofaríngeo y parafaríngeo son infecciones profundas del cuello que suelen asociarse al antecedente de infección de vías respiratorias altas. Ocasionalmente pueden ser causados por traumatismos como los que resultan de algunos procedimientos médicos, por ejemplo, la colocación de la mascarilla laríngea, muy utilizada en cirugía pediátrica. CASO CLÍNICO: Se presenta el caso de una niña de 6 años con tortícolis de 8 días de evolución y fiebre de 24 horas, sin otra sintomatología. La paciente había sido intervenida quirúrgicamente bajo anestesia general con colocación de mascarilla laríngea 36 horas antes del inicio del cuadro, sin incidencias. A la exploración, destaca una contractura cervical bilateral con flexión de la cabeza hacia la derecha, y en la analítica se encuentra leucocitosis con predominio neutrofílico y ligero aumento de proteína C reactiva. Se realiza una resonancia magnética cervical donde se observa un absceso de extensión parafaríngea y retrofaríngea, y se practica una punción percutánea ecoguiada de la zona abscesificada, que resulta positiva para S. pyogenes. La paciente ingresa con antibioterapia endovenosa y se consigue mejoría clínica y radiológica del absceso. COMENTARIO: Los abscesos cervicales profundos deben considerarse ante sintomatología obstructiva e inflamatoria de la vía aérea y del tracto digestivo superior, y síntomas locales o dolor al movimiento del cuello. El diagnóstico se basa en los hallazgos radiológicos, analíticos y microbiológicos y se debe instaurar antibioterapia endovenosa empírica con cobertura para estafilococos, estreptococos y anaerobios. Aunque en la mayoría de casos estos abscesos son secundarios a la extensión de infecciones del tracto respiratorio superior, existen otras causas que deben considerarse
INTRODUCTION: Retropharyngeal and parapharyngeal abscesses are deep neck infections that are usually associated with superior airway infections in children. However, they could also be caused by injuries secondary to medical procedures such as the placement of laryngeal masks, which are frequently used in pediatric surgery. CASE REPORT: A 6-year-old female presented to the emergency room with an 8-day history of torticollis and 24 hours of fever with no other associated symptomatology. She had undergone surgery under general anesthesia using a laryngeal mask 36 hours prior, without immediate complications. In the physical examination, the patient had bilateral cervical contracture with right bending. The blood examination showed leukocytosis with predominance of neutrophils and increase of C-reactive protein. Magnetic resonance imaging showed an abscess with parapharyngeal and retropharyngeal extension, and a percutaneous ultrasound-guided puncture of the abscessed area was performed, which resulted positive for S. pyogenes. The patient received intravenous antibiotic therapy and achieved clinical and radiological resolution of the abscess. COMMENTS: Deep neck abscesses should be considered in children with obstructive and inflammatory symptomatology of the airway and upper digestive tract and also local symptoms as neck pain. Diagnosis is based on radiological, analytical and microbiological findings and empirical intravenous antibiotics, with coverage for staphylococcus, streptococcus and anaerobics. Although in most cases these abscesses are secondary to the spread of upper respiratory tract infections, other causes should be considered
Assuntos
Humanos , Feminino , Criança , Máscaras Laríngeas/efeitos adversos , Abscesso Retrofaríngeo/diagnóstico por imagem , Leucocitose/diagnóstico , Abscesso Retrofaríngeo/cirurgia , Doenças Faríngeas/terapia , Doenças Faríngeas/etiologia , Abscesso Retrofaríngeo/etiologia , Torcicolo/etiologia , Leucocitose/tratamento farmacológico , Leucocitose/microbiologia , Espectroscopia de Ressonância Magnética , Biópsia por Agulha , Antibacterianos/uso terapêuticoRESUMO
Com objetivo de estudar a representacao social que os jovens tem das suas familias, aplicou-se um questionario em 97 estudantes do segundo grau, que frequentavam duas escolas publicas e duas particulares da cidade de Salvador (BA). Os itens do questionario abordavam conteudos sobre: relacoes interpessoais, os papeis que cada membro do grupo familiar desempenha, o significado destes papeis para os adolescentes e as suas concepcoes de familia. Nao foram constatadas diferencas significativas entre as concepcoes de familia dos jovens pertecentes as escolas publicas e particulares. De maneira geral, todos consideraram a familia indispensavel na formacao do individuo.