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Myelodysplastic neoplasms (MDS) are a heterogenous group of clonal stem cell disorders characterized by dysplasia and cytopenia in one or more cell lineages. Anemia is a very common symptom that is often treated with blood transfusions and/or erythropoiesis stimulating factors. Iron overload results from a combination of these factors together with the disease-associated ineffective erythropoiesis, that is seen especially in MDS cases with SF3B1 mutations. A growing body of research has shown that erythroferrone is an important regulator of hepcidin, the master regulator of systemic iron homeostasis. Consequently, it is of interest to understand how this molecule contributes to regulating the iron balance in MDS patients. This short review evaluates our current understanding of erythroferrone in general, but more specifically in MDS and seeks to place in context how the current knowledge could be utilized for prognostication and therapy.
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BACKGROUND: Studies investigating the diagnostic and prognostic value of the neutrophil-to-lymphocyte ratio (NLR) in sepsis or septic shock commonly included preselected subgroups of patients or were published prior to the current sepsis-3 criteria. Therefore, this study investigates the diagnostic and prognostic impact of the NLR in patients with sepsis and septic shock. METHODS: Consecutive patients with sepsis and septic shock from 2019 to 2021 from the prospective "MARSS-registry" were included monocentrically. First, the diagnostic value of the NLR compared to established sepsis scores was tested for septic shock compared to sepsis. Second, the diagnostic value of the NLR with regard to positive blood cultures was tested. Thereafter, the prognostic value of the NLR was tested for 30-day all-cause mortality. Statistical analyses included univariable t-tests, Spearman´s correlations, C-statistics, Kaplan-Meier analyses, Cox proportional regression analyses as well as uni- and multivariate logistic regression models. RESULTS: A total of 104 patients were included, of which 60% were admitted with sepsis and 40% with septic shock. The overall rate of all-cause mortality at 30 days was 56%. With an area under the curve (AUC) of 0.492, the NLR was shown to have a poor diagnostic value with regard to the diagnosis of septic shock compared to sepsis. However, the NLR was shown to be a reliable parameter to discriminate between patients with negative and positive blood cultures when admitted with septic shock (AUC = 0.714). This was still evident after multivariable adjustment (OR = 1.025; 95% CI 1.000 - 1.050; p = 0.048). In contrast, the NLR revealed a poor prognostic accuracy (AUC = 0.507) with regard to 30-day all-cause mortality. Finally, a higher NLR was not associated with an increased risk of 30-day all-cause mortality (log rank p-value = 0.775). CONCLUSIONS: The NLR was a reliable diagnostic tool for the identification of patients with blood culture confirmed sepsis. Yet, the NLR was not a reliable parameter to discriminate between patients with sepsis and septic shock nor between 30-day survivors and non-survivors.
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Sepsis , Choque Séptico , Humanos , Pronóstico , Neutrófilos , Estudios Prospectivos , Linfocitos , Estudios Retrospectivos , Curva ROCRESUMEN
The study investigates the prognostic significance of beta-blocker (BB) dose in patients with ventricular tachyarrhythmias. Limited data regarding the prognostic impact of BB dose in ventricular tachyarrhythmias is available. A large retrospective registry was used including consecutive patients on BB treatment with episodes of ventricular tachycardia (VT) or fibrillation (VF) from 2002 to 2015. Discharge BB doses were grouped as > 0-12.5%, > 12.5-25%, > 25-50%, and > 50% according to doses used in randomized trials. The primary endpoint was all-cause mortality at three years. Secondary endpoints comprised of a composite arrhythmic endpoint (i.e., recurrences of ventricular tachyarrhythmias and appropriate ICD therapies) and cardiac rehospitalization. Kaplan-Meier survival curves and multivariable Cox regression analyses were applied for statistics. A total of 1313 patients with BB were included; most patients were discharged with > 25-50% of BB target dose (59%). At three years, > 12.5-25% of BB target dose was associated with improved long-term mortality as compared to the > 0-12.5% group (HR = 0.489; 95% CI 0.297-0.806; p = 0.005), whereas higher BB doses did not improve survival (> 25-50%: HR = 0.849; p = 0.434; > 50%: HR = 0.735; p = 0.285). In contrast, the composite endpoint and risk of rehospitalization were not affected by BB target dose. In conclusion, > 12.5-25% of BB target dose is associated with best long-term survival among patients with ventricular tachyarrhythmias. In contrast, risk of the composite arrhythmic endpoint and risk of cardiac rehospitalization were not affected by BB dose.
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Desfibriladores Implantables , Taquicardia Ventricular , Antagonistas Adrenérgicos beta/uso terapéutico , Desfibriladores Implantables/efectos adversos , Humanos , Pronóstico , Recurrencia , Estudios Retrospectivos , Factores de Riesgo , Taquicardia Ventricular/diagnóstico , Taquicardia Ventricular/tratamiento farmacológico , Taquicardia Ventricular/etiología , Fibrilación Ventricular/diagnóstico , Fibrilación Ventricular/tratamiento farmacológicoRESUMEN
INTRODUCTION: The study sought to assess the effect of treatment with mineralocorticoid receptor antagonists (MRAs) on long-term prognosis of patients with systolic heart failure (HF) surviving index episodes of ventricular tachyarrhythmias. METHODS: A large retrospective registry was used including consecutive HF patients with left ventricular ejection fraction <45% and index episodes of ventricular tachyarrhythmias from 2002 to 2015. The primary endpoint was all-cause mortality at 3 years and secondary endpoints were rehospitalization, as well as the composite endpoint consisting of recurrent ventricular tachyarrhythmias, sudden cardiac death and appropriate implantabe cardioverter defibrillator (ICD) therapies at 3 years. RESULTS: 748 patients were included, 20% treated with MRA and 80% without. At 3 years, treatment with MRA was not associated with improved all-cause mortality (22% vs. 24%, log-rank p = 0.968; hazard ratio (HR) = 1.008; 95% CI 0.690-1.472; p = 0.968). Accordingly, risk of the composite endpoint (28% vs. 27%; HR = 1.131; 95% CI 0.806-1.589; p = 0.476) and first cardiac rehospitalization (24% vs. 22%; HR = 1.139; 95% CI 0.788-1.648; p = 0.489) were not affected by treatment with MRA. CONCLUSION: In patients with ventricular tachyarrhythmias, treatment with MRA was not associated with improved all-cause mortality at 3 years. The therapeutic effect of MRA treatment in patients with ventricular tachyarrhythmias needs to be reinvestigated within further randomized controlled trials.
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Antagonistas de Receptores de Mineralocorticoides/farmacología , Antagonistas de Receptores de Mineralocorticoides/uso terapéutico , Taquicardia Ventricular/tratamiento farmacológico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Eplerenona/farmacología , Eplerenona/uso terapéutico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Pronóstico , Sistema de Registros , Estudios Retrospectivos , Espironolactona/farmacología , Espironolactona/uso terapéutico , Taquicardia Ventricular/diagnóstico , Taquicardia Ventricular/mortalidad , Adulto JovenRESUMEN
MiRs are important players in cancer and primarily genetic/transcriptional means of regulating their gene expression are known. However, epigenetic changes modify gene expression significantly. Here, we evaluated genome-wide methylation changes focusing on miR genes from primary CRC and corresponding normal tissues. Differentially methylated CpGs spanning CpG islands, open seas, and north and south shore regions were evaluated, with the largest number of changes observed within open seas and islands. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis revealed several of these miRs to act in important cancer-related pathways, including phosphatidylinositol 3-kinase (PI3K)-protein kinase B (Akt) and mitogen-activated protein kinase (MAPK) pathways. We found 18 miR genes to be significantly differentially methylated, with MIR124-2, MIR124-3, MIR129-2, MIR137, MIR34B, MIR34C, MIR548G, MIR762, and MIR9-3 hypermethylated and MIR1204, MIR17, MIR17HG, MIR18A, MIR19A, MIR19B1, MIR20A, MIR548F5, and MIR548I4 hypomethylated in CRC tumor compared with normal tissue, most of these miRs having been shown to regulate steps of metastasis. Generally, methylation changes were distributed evenly across all chromosomes with predominance for chromosomes 1/2 and protein-coding genes. Interestingly, chromosomes abundantly affected by methylation changes globally were rarely affected by methylation changes within miR genes. Our findings support additional mechanisms of methylation changes affecting (miR) genes that orchestrate CRC progression and metastasis.
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The paucity of microbiome studies at intestinal tissues has contributed to a yet limited understanding of potential viral and bacterial cofactors of colorectal cancer (CRC) carcinogenesis or progression. We analysed whole-genome sequences of CRC primary tumours, their corresponding metastases and matched normal tissue for sequences of viral, phage and bacterial species. Bacteriome analysis showed Fusobacterium nucleatum, Streptococcus sanguinis, F. Hwasookii, Anaerococcus mediterraneensis and further species enriched in primary CRCs. The primary CRC of one patient was enriched for F. alocis, S. anginosus, Parvimonas micra and Gemella sp. 948. Enrichment of Escherichia coli strains IAI1, SE11, K-12 and M8 was observed in metastases together with coliphages enterobacteria phage φ80 and Escherichia phage VT2φ_272. Virome analysis showed that phages were the most preponderant viral species (46%), the main families being Myoviridae, Siphoviridae and Podoviridae. Primary CRCs were enriched for bacteriophages, showing five phages (Enterobacteria, Bacillus, Proteus, Streptococcus phages) together with their pathogenic hosts in contrast to normal tissues. The most frequently detected, and Blast-confirmed, viruses included human endogenous retrovirus K113, human herpesviruses 7 and 6B, Megavirus chilensis, cytomegalovirus (CMV) and Epstein-Barr virus (EBV), with one patient showing EBV enrichment in primary tumour and metastases. EBV was PCR-validated in 80 pairs of CRC primary tumour and their corresponding normal tissues; in 21 of these pairs (26.3%), it was detectable in primary tumours only. The number of viral species was increased and bacterial species decreased in CRCs compared with normal tissues, and we could discriminate primary CRCs from metastases and normal tissues by applying the Hutcheson t-test on the Shannon indices based on viral and bacterial species. Taken together, our results descriptively support hypotheses on microorganisms as potential (co)risk factors of CRC and extend putative suggestions on critical microbiome species in CRC metastasis.
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Neoplasias Colorrectales , Infecciones por Virus de Epstein-Barr , Microbiota , Neoplasias Colorrectales/genética , Herpesvirus Humano 4 , Humanos , Factores de RiesgoRESUMEN
Incomplete understanding of the metastatic process hinders personalized therapy. Here we report the most comprehensive whole-genome study of colorectal metastases vs. matched primary tumors. 65% of somatic mutations originate from a common progenitor, with 15% being tumor- and 19% metastasis-specific, implicating a higher mutation rate in metastases. Tumor- and metastasis-specific mutations harbor elevated levels of BRCAness. We confirm multistage progression with new components ARHGEF7/ARHGEF33. Recurrently mutated non-coding elements include ncRNAs RP11-594N15.3, AC010091, SNHG14, 3' UTRs of FOXP2, DACH2, TRPM3, XKR4, ANO5, CBL, CBLB, the latter four potentially dual protagonists in metastasis and efferocytosis-/PD-L1 mediated immunosuppression. Actionable metastasis-specific lesions include FAT1, FGF1, BRCA2, KDR, and AKT2-, AKT3-, and PDGFRA-3' UTRs. Metastasis specific mutations are enriched in PI3K-Akt signaling, cell adhesion, ECM and hepatic stellate activation genes, suggesting genetic programs for site-specific colonization. Our results put forward hypotheses on tumor and metastasis evolution, and evidence for metastasis-specific events relevant for personalized therapy.
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Adenocarcinoma/genética , Neoplasias Colorrectales/genética , Neoplasias Hepáticas/genética , Medicina de Precisión , Regiones no Traducidas 3'/genética , Proteínas Adaptadoras Transductoras de Señales/genética , Adenocarcinoma/secundario , Anciano , Anoctaminas/genética , Proteínas Reguladoras de la Apoptosis , Proteína BRCA2/genética , Adhesión Celular/genética , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/terapia , Proteínas de Unión al ADN , Matriz Extracelular/genética , Femenino , Factores de Transcripción Forkhead/genética , Células Estrelladas Hepáticas/metabolismo , Humanos , Neoplasias Hepáticas/secundario , Masculino , Proteínas de la Membrana , Proteínas de Transporte de Membrana/genética , Persona de Mediana Edad , Metástasis de la Neoplasia , Proteínas Nucleares/genética , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-cbl/genética , ARN no Traducido , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/genética , Factores de Intercambio de Guanina Nucleótido Rho/genética , Transducción de Señal , Canales Catiónicos TRPM/genética , Factores de Transcripción/genética , Receptor 2 de Factores de Crecimiento Endotelial Vascular/genética , Secuenciación Completa del GenomaRESUMEN
Artemisia annua (sweet wormwood, qinhao) is an ancient Chinese herbal remedy for pyrexia. Nowadays, artemisinin (qinghaosu) and its derivatives belong to the standard therapies against malaria worldwide, and its discovery has led to the Nobel Prize in Physiology and Medicine to Youyou Tu in 2015. While most attention has been paid to the treatment of malaria, there is increasing evidence that Artemisinin-type drugs bear a considerable potential to treat and prevent cancer. Rather than reporting on therapy of cancer, this review gives a comprehensive and timely overview on the chemopreventive effects of artemisinin and its derivatives against carcinogenesis and metastasis formation, following the multistage model of carcinogenesis (initiation, promotion, progression). The favorable toxicity profile known from malaria studies indicates that artemisinin-type drugs may be safely applied to prevent carcinogenesis and cancer metastasis in human beings.
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Artemisia annua/química , Artemisininas/uso terapéutico , Carcinogénesis/efectos de los fármacos , Neoplasias/prevención & control , Antimaláricos/química , Antimaláricos/uso terapéutico , Artemisininas/química , Carcinogénesis/patología , Ensayos Clínicos como Asunto/métodos , Ensayos Clínicos como Asunto/estadística & datos numéricos , Humanos , Estructura Molecular , Metástasis de la Neoplasia , Neoplasias/patología , Fitoterapia/métodosRESUMEN
Inhibitor of DNA binding (ID) proteins are a class of helix-loop-helix (HLH) transcription regulatory factors that act as dominant-negative antagonists of other basic HLH proteins through the formation of non-functional heterodimers. These proteins have been shown to play critical roles in a wide range of tumor-associated processes, including cell differentiation, cell cycle progression, migration and invasion, epithelial-mesenchymal transition, angiogenesis, stemness, chemoresistance, tumorigenesis, and metastasis. The aberrant expression of ID proteins has not only been detected in many types of human cancers, but is also associated with advanced tumor stages and poor clinical outcome. In this review, we provide an overview of the key biological functions of ID proteins including affiliated signaling pathways. We also describe the regulation of ID proteins in cancer progression and metastasis, and elaborate on expression profiles in cancer and the implications for prognosis. Lastly, we outline strategies for the therapeutic targeting of ID proteins as a promising and effective approach for anticancer therapy.
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The standard radiation dose 50.4 Gy with concurrent chemotherapy for localized inoperable esophageal cancer as supported by INT-0123 trail is now being challenged since a radiation dose above 50 Gy has been successfully administered with an observable dose-response relationship and insignificant untoward effects. Therefore, to ascertain the treatment benefits of different radiation doses, we performed a meta-analysis with 18 relative publications. According to our findings, a dose between 50 and 70 Gy appears optimal and patients who received ≥ 60 Gy radiation had a significantly better prognosis (pooled HR = 0.78, P = 0.004) as compared with < 60 Gy, especially in Asian countries (pooled HR = 0.75, P = 0.003). However, contradictory results of treatment benefit for ≥ 60 Gy were observed in two studies from Western countries, and the pooled treatment benefit of ≥ 60 Gy radiation was inconclusive (pooled HR = 0.86, P = 0.64). There was a marginal benefit in locoregional control in those treated with high dose (> 50.4/51 Gy) radiation when compared with those treated with low dose (≤ 50.4/51 Gy) radiation (pooled OR = 0.71, P = 0.06). Patients that received ≥ 60 Gy radiation had better locoregional control (OR = 0.29, P = 0.001), and for distant metastasis control, neither the > 50.4 Gy nor the ≥ 60 Gy treated group had any treatment benefit as compared to the groups that received ≤ 50.4 Gy and < 60 Gy group respectively. Taken together, a dose range of 50 to 70 Gy radiation with CCRT is recommended for non-operable EC patients. A dose of ≥ 60 Gy appears to be better in improving overall survival and locoregional control, especially in Asian countries, while the benefit of ≥ 60 Gy radiation in Western countries still remains controversial.
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Photodynamic therapy (PDT) is a non-invasive treatment modality used in the management of both benign and malignant conditions. It involves the administration of a photosensitizing agent followed by local light irradiation, which activates the photosensitizer, resulting in tissue damage. An in-depth understanding of the molecular mechanisms and mediators of PDT is important, not only for appreciating how this treatment modality is effective, but also as an avenue for understanding potential shortfalls and untoward effects that can be managed or improved. MicroRNAs are a group of endogenous small non-coding regulatory molecules that play important roles in regulating several physiological processes and have been implicated in several pathologies including cancer. They have been found to regulate key cellular pathways and their aberrant expression highlights not only disease onset or progression, but is associated with therapy resistance and disease outcome. In the present review, we evaluate the role of microRNAs in PDT and dissect their function as effectors of PDT including the molecules they regulate. We also look at how miRNA signatures can be used as predictors of therapy response to PDT and what implications this may have in the treatment of patients with PDT.
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MicroARNs/genética , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Fotoquimioterapia , Fármacos Fotosensibilizantes/farmacología , Animales , Apoptosis/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Neoplasias/patología , Fármacos Fotosensibilizantes/uso terapéutico , Transcriptoma/efectos de los fármacosRESUMEN
The tumor suppressor P53 is a critical regulator of normal cellular homeostasis whose function is either distorted or lost in several cancer types including colorectal cancer (CRC). A small group of microRNAs have come to be recognized as essential mediators of P53 function. In a genome-wide systematic approach, we explored miRNAs that are substantially altered by P53 loss and found miR-30e to be the most significantly deregulated miRNA in P53-knockout human CRC cells. We identified miR-30e-5p to be a novel direct transcriptional target of P53 with gain and loss of function experiments revealing miR-30e-5p to be a significant regulator of tumor cell migration, invasion and in vivo metastasis mediated in part by integrins alpha-6 and beta-1 as novel targets. MiR-30e-5p also significantly reduced tumor cell proliferation by causing G1/S cell cycle arrest, which was achieved by inducing P21 and P27 expression. Finally, we found miR-30e-5p to be lost in resected CRC tumors as compared to normal colon tissues. Taken together, miR-30e-5p is a novel effector of P53-induced suppression of migration, invasion and metastasis.
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Neoplasias Colorrectales/genética , Integrina alfa6/genética , Péptidos y Proteínas de Señalización Intracelular/genética , Proteínas de la Membrana/genética , MicroARNs/genética , Proteína p53 Supresora de Tumor/genética , Proteínas Adaptadoras Transductoras de Señales , Animales , Puntos de Control del Ciclo Celular/genética , Línea Celular Tumoral , Proliferación Celular/genética , Neoplasias Colorrectales/patología , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Inhibidor p27 de las Quinasas Dependientes de la Ciclina/genética , Regulación Neoplásica de la Expresión Génica , Células HCT116 , Humanos , Ratones , Invasividad Neoplásica/genética , Invasividad Neoplásica/patología , Metástasis de la Neoplasia , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Personalized and precision medicine is gaining recognition due to the limitations by standard diagnosis and treatment; many areas of medicine, from cancer to psychiatry, are moving towards tailored and individualized treatment for patients based on their clinical characteristics and genetic signatures as well as novel imaging techniques. Advances in whole genome sequencing have led to identification of genes involved in a variety of diseases. Moreover, biomarkers indicating severity of disease or susceptibility to treatment are increasingly being characterized. The continued identification of new genes and biomarkers specific to disease subtypes and individual patients is essential and inevitable for translation into personalized medicine, in estimating both, disease risk and response to therapy. Taking into consideration the mostly unsolved necessity of tailored therapy in oncology the innovative project MOBIT (molecular biomarkers for individualized therapy) was designed. The aims of the project are: (i) establishing integrative management of precise tumor diagnosis and therapy including systematic biobanking, novel imaging techniques, and advanced molecular analysis by collecting comprehensive tumor tissues, liquid biopsies (whole blood, serum, plasma), and urine specimens (supernatant; sediment) as well as (ii) developing personalized lung cancer diagnostics based on tumor heterogeneity and integrated genomics, transcriptomics, metabolomics, and radiomics PET/MRI analysis. It will consist of 5 work packages. In this paper the rationale of the Polish MOBIT project as well as its design is presented. (iii) The project is to draw interest in and to invite national and international, private and public, preclinical and clinical initiatives to establish individualized and precise procedures for integrating novel targeted therapies and advanced imaging techniques.
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Bancos de Muestras Biológicas , Biomarcadores de Tumor/análisis , Imagen Molecular , Terapia Molecular Dirigida , Neoplasias/diagnóstico , Neoplasias/terapia , Medicina de Precisión , Humanos , Metaboloma , Valor Predictivo de las Pruebas , ProteomaRESUMEN
MicroRNAs (miRNAs) are currently experiencing a renewed peak of attention not only as diagnostics but also especially as highly promising novel targets or tools for clinical therapy in several different malignant diseases. Moreover, the recent discovery of competing endogenous RNAs (ceRNAs) as novel miRNA-regulators has contributed exciting insights in this regard. Therefore, this review summarizes and discusses the latest findings on (1) how miRNAs have become therapeutic targets of diverse synthetic antagonists, (2) how novel endogenous regulators of miRNAs such as ceRNAs or pseudogenes could emerge as therapeutics scavenging oncogenic miRNAs and (3) how miRNAs themselves are already, and will increasingly be, used as therapeutics. Recent advances on the importance of miRNA-target affinity and the subcellular localization of miRNAs are also discussed. The potential of these developments in different tumor entities and particular hallmarks of cancer such as metastasis, disease progression, interactions with the tumor microenvironment, or cancer stem cells are equally highlighted.
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Regulación Neoplásica de la Expresión Génica , Genes Supresores de Tumor , MicroARNs/genética , Neoplasias/diagnóstico , Neoplasias/genética , Neoplasias/terapia , Oncogenes/genética , Animales , HumanosRESUMEN
Two molecular beacons were designed as complementary fluorescent imaging probes for miRNA-21 and miRNA-31. Both beacons were prepared by a combination of solid-phase protocol and Cu(i)-catalyzed cycloaddition chemistry. The four photostable and bright fluorophores were attached to 2'-positions in the stem part of the two beacons. One beacon was labeled by a green-to-red emitting and the other by a blue-to-yellow emitting energy transfer pair. This two by two combination yields the four color emission readout. In vitro experiments demonstrate rapid and highly selective opening of both molecular beacons upon addition of the complementary target RNA and excellent green : red and blue : yellow emission color contrasts. Confocal microscopy of selected cancer cell lines provides evidence that a four color imaging of versicular miRNA-21 and miRNA-31 can be achieved both selectively and simultaneously upon transfection by the beacons, and that the fluorescent readouts track well with miRNA levels determined by PCR.
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MicroARNs/metabolismo , Sondas de Oligonucleótidos/metabolismo , Imagen Óptica/métodos , Línea Celular Tumoral , Supervivencia Celular , Humanos , Espacio Intracelular/metabolismo , Sondas de Oligonucleótidos/química , Factores de TiempoRESUMEN
Growth factor receptor signalling plays a central and critical role in colorectal cancer. Most importantly, the EGFR signalling cascade involving PI3K/AKT/mTOR and Raf/MEK/ERK pathways are particularly relevant, since they are commonly activated in several cancer entities, including colorectal cancer. In this study, we show that miRs-134 and -370 are both capable of regulating these pathways by targeting EGFR and PIK3CA. In three different colorectal cancer cell lines (DLD1, HCT-116 and RKO), suppression of EGFR and PIK3CA through the enhanced expression of miR-134 or -370 led to a suppression of the key molecules of the PI3K/AKT/mTOR pathway. Furthermore, overexpression of miR-134 or -370 resulted in a significant reduction of cell proliferation, colony formation, migration, invasion and in-vivo tumor growth and metastasis. Concurrent experiments with small interfering RNAs targeting the prime targets show that our selected miRNAs exert a greater functional influence and affect more downstream molecules than is seen with silencing of the individual proteins. Taken together, these data indicate that miRs-134 and -370 are potential tumour suppressor miRNAs and could play a fundamental role in suppressing colorectal cancer tumorigenesis through their ability to co-ordinately regulate EGFR signalling cascade by independently targeting EGFR and PIK3CA.
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Neoplasias Colorrectales/genética , Neoplasias Colorrectales/metabolismo , Receptores ErbB/metabolismo , MicroARNs/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Transducción de Señal , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular , Expresión Génica , Regulación Neoplásica de la Expresión Génica , Genes Supresores de Tumor , Humanos , Sistema de Señalización de MAP Quinasas , Metástasis de la Neoplasia , Proteínas Proto-Oncogénicas c-akt/metabolismo , Interferencia de ARN , Serina-Treonina Quinasas TOR/metabolismo , Carga TumoralRESUMEN
Epithelial to mesenchymal transition (EMT) is a central regulatory program that is similar in many aspects to several steps of embryonic morphogenesis. In addition to its physiological role in tissue repair and wound healing, EMT contributes to chemo resistance, metastatic dissemination and fibrosis, amongst others. Classically, the morphological change from epithelial to mesenchymal phenotype is characterized by the appearance or loss of a group of proteins which have come to be recognized as markers of the EMT process. As with all proteins, these molecules are controlled at the transcriptional and translational level by transcription factors and microRNAs, respectively. A group of developmental transcription factors form the backbone of the EMT cascade and a large body of evidence shows that microRNAs are heavily involved in the successful coordination of mesenchymal transformation and vice versa, either by suppressing the expression of different groups of transcription factors, or otherwise acting as their functional mediators in orchestrating EMT. This article dissects the contribution of microRNAs to EMT and analyzes the molecular basis for their roles in this cellular process. Here, we emphasize their interaction with core transcription factors like the zinc finger enhancer (E)-box binding homeobox (ZEB), Snail and Twist families as well as some pluripotency transcription factors.