RESUMEN

We previously reported that intronic single nucleotide variations (SNVs) in MITF (c.938-325G>A, rs7623610) and CREB1 (c.303+373G>A, rs10932201) genes were associated with risk, aggressiveness, and prognosis of cutaneous melanoma (CM). In this study, we investigated the influence of the above SNVs in splicing patterns and efficiency. We constructed minigenes with wild type and variant alleles from MITF and CREB1 to assess the effect of the SNVs on splicing. The minigenes were transfected in the human melanoma cell line (SK-MEL-28). RT-PCR and DNA sequencing investigated the constructs' splicing patterns. Minigenes constructs' splicing efficiency and HNRNPA1 and SF1 splicing genes' expression were investigated by qPCR. We found that MITF and CREB1 SNVs did not alter the splicing pattern, but they influenced the splicing efficiency. MITF-A (p= 0.03) and CREB1-A (p= 0.005) variant minigenes yielded an increase of mRNA generated from the constructions. Additionally, lower mRNA levels of HNRNPA1 and SF1 were seen in the variant minigenes MITF-A (p= 0.04) and CREB1-A (p= 0.005). We described for the first time the potential importance of MITF rs7623610 and CREB1 rs10932201 SNVs in splicing efficiency and its relationship with CM.

Asunto(s)

Proteína de Unión a Elemento de Respuesta al AMP Cíclico/genética , Intrones , Melanoma/genética , Factor de Transcripción Asociado a Microftalmía/genética , Mutación , Empalme del ARN , Neoplasias Cutáneas/genética , Alelos , Secuencia de Bases , Línea Celular Tumoral , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Ingeniería Genética/métodos , Humanos , Melanoma/metabolismo , Factor de Transcripción Asociado a Microftalmía/metabolismo , Plásmidos/química , Plásmidos/metabolismo , Polimorfismo de Nucleótido Simple , ARN Neoplásico/genética , ARN Neoplásico/metabolismo , Neoplasias Cutáneas/metabolismo , Melanoma Cutáneo Maligno

RESUMEN

Non-coding RNAs are emergent elements from the genome, which do not encode for proteins but have relevant cellular functions impacting almost all the physiological processes occurring in eukaryotic cells. In particular, microRNAs and long non-coding RNAs (lncRNAs) are a new class of small RNAs transcribed from the genome, which modulate the expression of specific genes at transcriptional and posttranscriptional levels, thus adding a new regulatory layer in the flux of genetic information. In cancer cells, the miRNAs and lncRNAs interactions with its target genes and functional pathways are deregulated as a consequence of epigenetic and genetic alterations occurring during tumorigenesis. In this review, we summarize the actual knowledge on the interplay of lncRNAs with its cognate miRNAs and mRNAs pairs, which interact in coregulatory networks with a particular emphasis on the mechanisms underlying its oncogenic behavior in ovarian cancer. Specifically, we reviewed here the evidences unraveling the relevant roles of lncRNAs/miRNAs pairs in altered regulation of cell migration, angiogenesis, therapy resistance, and Warburg effect. Finally, we also discussed its potential clinical implications in ovarian cancer and related endocrine disease therapies.

Asunto(s)

Redes Reguladoras de Genes , MicroARNs/metabolismo , Neovascularización Patológica/metabolismo , Neoplasias Ováricas/irrigación sanguínea , Neoplasias Ováricas/metabolismo , ARN Largo no Codificante/metabolismo , ARN Neoplásico/metabolismo , Movimiento Celular/genética , Femenino , Humanos , MicroARNs/genética , Neovascularización Patológica/genética , Neoplasias Ováricas/genética , ARN Largo no Codificante/genética , ARN Neoplásico/genética

RESUMEN

Platelets play significant and varied roles in cancer progression, as detailed throughout this review series, via direct interactions with cancer cells and by long-range indirect interactions mediated by platelet releasates. Microvesicles (MVs; also referred to as microparticles) released from activated platelets have emerged as major contributors to the platelet-cancer nexus. Interactions of platelet-derived MVs (PMVs) with cancer cells can promote disease progression through multiple mechanisms, but PMVs also harbor antitumor functions. This complex relationship derives from PMVs' binding to both cancer cells and nontransformed cells in the tumor microenvironment and transferring platelet-derived contents to the target cell, each of which can have stimulatory or modulatory effects. MVs are extracellular vesicles of heterogeneous size, ranging from 100 nm to 1 µm in diameter, shed by living cells during the outward budding of the plasma membrane, entrapping local cytosolic contents in an apparently stochastic manner. Hence, PMVs are encapsulated by a lipid bilayer harboring surface proteins and lipids mirroring the platelet exterior, with internal components including platelet-derived mature messenger RNAs, pre-mRNAs, microRNAs, and other noncoding RNAs, proteins, second messengers, and mitochondria. Each of these elements engages in established and putative PMV functions in cancer. In addition, PMVs contribute to cancer comorbidities because of their roles in coagulation and thrombosis and via interactions with inflammatory cells. However, separating the effects of PMVs from those of platelets in cancer contexts continues to be a major hurdle. This review summarizes our emerging understanding of the complex roles of PMVs in the development and progression of cancer and cancer comorbidities.

Asunto(s)

Plaquetas/metabolismo , Comunicación Celular , Vesículas Extracelulares/metabolismo , Neoplasias/metabolismo , ARN Neoplásico/metabolismo , Microambiente Tumoral , Animales , Plaquetas/patología , Vesículas Extracelulares/patología , Humanos , Neoplasias/patología

RESUMEN

Aberrant expression of the pluripotency factor OCT4A in embryonal tumors of the central nervous system (CNS) is a key factor that contributes to tumor aggressiveness and correlates with poor patient survival. OCT4A overexpression has been shown to up-regulate miR-367, a microRNA (miRNA) that regulates pluripotency in embryonic stem cells and stem-like aggressive traits in cancer cells. Here, we show that (a) miR-367 is carried in microvesicles derived from embryonal CNS tumor cells expressing OCT4A; and (b) inhibition of miR-367 in these cells attenuates their aggressive traits. miR-367 silencing in OCT4A-overexpressing tumor cells significantly reduced their proliferative and invasive behavior, clonogenic activity, and tumorsphere generation capability. In vivo, targeting of miR-367 through direct injections of a specific inhibitor into the cerebrospinal fluid of Balb/C nude mice bearing OCT4A-overexpressing tumor xenografts inhibited tumor development and improved overall survival. miR-367 was also shown to target SUZ12, one of the core components of the polycomb repressive complex 2 known to be involved in epigenetic silencing of pluripotency-related genes, including POU5F1, which encodes OCT4A. Our findings reveal possible clinical applications of a cancer stemness pathway, highlighting miR-367 as a putative liquid biopsy biomarker that could be further explored to improve early diagnosis and prognosis prediction, and potentially serve as a therapeutic target in aggressive embryonal CNS tumors.

Asunto(s)

Biomarcadores de Tumor , Neoplasias del Sistema Nervioso Central , Silenciador del Gen , MicroARNs , Neoplasias de Células Germinales y Embrionarias , Células Madre Neoplásicas , ARN Neoplásico , Animales , Biomarcadores de Tumor/antagonistas & inhibidores , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Línea Celular Tumoral , Neoplasias del Sistema Nervioso Central/tratamiento farmacológico , Neoplasias del Sistema Nervioso Central/genética , Neoplasias del Sistema Nervioso Central/metabolismo , Neoplasias del Sistema Nervioso Central/patología , Células HEK293 , Humanos , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , MicroARNs/antagonistas & inhibidores , MicroARNs/genética , MicroARNs/metabolismo , Neoplasias de Células Germinales y Embrionarias/tratamiento farmacológico , Neoplasias de Células Germinales y Embrionarias/genética , Neoplasias de Células Germinales y Embrionarias/metabolismo , Neoplasias de Células Germinales y Embrionarias/patología , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología , ARN Neoplásico/antagonistas & inhibidores , ARN Neoplásico/genética , ARN Neoplásico/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto

RESUMEN

Lung tumors are a frequent type of cancer in humans and a leading cause of death, and the late diagnostic contributes to high mortality rates. New therapeutic strategies are needed, and the heptapeptide angiotensin-(1-7) [ang-(1-7)] demonstrated the ability to control cancer growth rates and migration in vitro and in vivo. However, the possible use of the heptapeptide in clinical trials demands deeper analyses to elucidate molecular mechanisms of its effect in the target cells. In this study, we investigated relevant elements that control pro-inflammatory environment and cellular migration, focusing in the post-transcription mechanism using lung tumor cell line. In our cellular model, the microRNA-513a-3p was identified as a novel element targeting ITG-ß8, thereby controlling the protein level and its molecular function in the controlling of migration and pro-inflammatory environment. These findings provide useful information for future studies, using miR-513a-3p as an innovative molecular tool to control lung tumor cell migration, which will support more effective clinical treatment of the patients with the widely used chemotherapeutic agents, increasing survival rates.

Asunto(s)

Movimiento Celular , Cadenas beta de Integrinas/metabolismo , Neoplasias Pulmonares/metabolismo , MicroARNs/metabolismo , Modelos Biológicos , Proteínas de Neoplasias/metabolismo , ARN Neoplásico/metabolismo , Células A549 , Humanos , Cadenas beta de Integrinas/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , MicroARNs/genética , Proteínas de Neoplasias/genética , ARN Neoplásico/genética

RESUMEN

Genomic analyses have become an important tool to identify new avenues for therapy. This is especially true for cancer types with extremely poor outcomes, since our lack of effective therapies offers no tangible clinical starting point to build upon. The highly malignant brain tumor glioblastoma (GBM) exemplifies such a refractory cancer, with only 15 month average patient survival. Analyses of several hundred GBM samples compiled by the TCGA (The Cancer Genome Atlas) have produced an extensive transcriptomic map, identified prevalent chromosomal alterations, and defined important driver mutations. Unfortunately, clinical trials based on these results have not yet delivered an improvement on outcome. It is, therefore, necessary to characterize other regulatory routes known for playing a role in tumor relapse and response to treatment. Alternative splicing affects more than 90% of the human coding genes and it is an important source for transcript variation and gene regulation. Mutations and alterations in splicing factors are highly prevalent in multiple cancers, demonstrating the potential for splicing to act as a tumor driver. As a result, numerous genes are expressed as cancer-specific splicing isoforms that are functionally distinct from the canonical isoforms found in normal tissue. These include genes that regulate cancer-critical pathways such as apoptosis, DNA repair, cell proliferation, and migration. Splicing defects can even induce genomic instability, a common characteristic of cancer, and a driver of tumor evolution. Importantly, components of the splicing machinery are targetable; multiple drugs can inhibit splicing factors or promote changes in splicing which could be exploited to begin improving clinical outcomes. Here, we review the current literature and present a case for exploring RNA processing as therapeutic route for the treatment of GBM.

Asunto(s)

Neoplasias Encefálicas , Glioblastoma , Procesamiento Postranscripcional del ARN , ARN Neoplásico/genética , ARN Neoplásico/metabolismo , Animales , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/terapia , Glioblastoma/genética , Glioblastoma/metabolismo , Glioblastoma/terapia , Humanos

RESUMEN

Different from genetic alterations, the reversible nature of epigenetic modifications provides an interesting opportunity for the development of clinically relevant therapeutics in different tumors. In this study, we aimed to screen and validate candidate genes regulated by the epigenetic marker associated with transcriptional activation, histone acetylation, in gastric cancer (GC). We first compared gene expression profile of trichostatin A-treated and control GC cell lines using microarray assay. Among the 55 differentially expressed genes identified in this analysis, we chose the up-regulated genes BMP8B and BAMBI for further analyses, that included mRNA and histone acetylation quantification in paired GC and nontumor tissue samples. BMP8B expression was reduced in GC compared to nontumor samples (P < 0.01). In addition, reduced BMP8B expression was associated with poorly differentiated GC (P = 0.02). No differences or histopathological associations were identified concerning BAMBI expression. Furthermore, acetylated H3K9 and H4K16 levels at BMP8B were increased in GC compared to nontumors (P < 0.05). However, reduced levels of acetylated H3K9 and H4K16 were associated with poorly differentiated GC (P < 0.05). Reduced levels of acetylated H3K9 was also associated with diffuse-type histological GC (P < 0.05). Notably, reduced BMP8B mRNA and acetylated H4K16 levels were positively correlated in poorly differentiated GC (P < 0.05). Our study demonstrated that BMP8B seems to be a tumor suppressor gene regulated by H4K16 acetylation in poorly differentiated GC. Therefore, BMP8B may be a potential target for TSA-based therapies in this GC sample subset. J. Cell. Biochem. 118: 869-877, 2017. © 2016 Wiley Periodicals, Inc.

Asunto(s)

Proteínas Morfogenéticas Óseas/genética , Genes Supresores de Tumor , Histonas/metabolismo , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Acetilación , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adulto , Diferenciación Celular/genética , Línea Celular Tumoral , Epigénesis Genética , Femenino , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Ácidos Hidroxámicos/farmacología , Masculino , Persona de Mediana Edad , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Neoplásico/genética , ARN Neoplásico/metabolismo , Neoplasias Gástricas/tratamiento farmacológico

RESUMEN

MicroRNAs and siRNAs belong to a family of small noncoding RNAs which bind through partial sequence complementarity to 3'-UTR regions of mRNA from target genes, resulting in the regulation of gene expression. MicroRNAs have become an attractive target for genetic and pharmacological modulation due to the critical function of their target proteins in several signaling pathways, and their expression profiles have been found to be altered in various cancers. A promising technology platform for selective silencing of cell and/or viral gene expression using siRNAs is currently in development. Cervical cancer is the most common cancer in women in the developing world and sexually transmitted infection with HPV is the cause of this malignancy. Therefore, a cascade of abnormal events is induced during cervical carcinogenesis, including the induction of genomic instability, reprogramming of cellular metabolic pathways, deregulation of cell proliferation, inhibition of apoptotic mechanisms, disruption of cell cycle control mechanisms, and alteration of gene expression. Thus, in the present review article, we highlight new research on microRNA expression profiles which may be utilized as biomarkers for cervical cancer. Furthermore, we discuss selective silencing of HPV E6 and E7 with siRNAs which represents a potential gene therapy strategy against cervical cancer.

Asunto(s)

MicroARNs/metabolismo , ARN Neoplásico/metabolismo , ARN Interferente Pequeño/metabolismo , Neoplasias del Cuello Uterino/metabolismo , Femenino , Humanos , MicroARNs/genética , Proteínas Oncogénicas Virales/genética , Proteínas Oncogénicas Virales/metabolismo , Papillomaviridae/genética , Papillomaviridae/metabolismo , Infecciones por Papillomavirus/genética , Infecciones por Papillomavirus/metabolismo , ARN Neoplásico/genética , ARN Interferente Pequeño/genética , Neoplasias del Cuello Uterino/genética

RESUMEN

This article is based on a study of a reform in the organisation of maternity services in the United Kingdom, which aimed towards developing a more woman-centred model of care. After decades of fragmentation and depersonalisation of care, associated with the shift of birth to a hospital setting, pressure by midwives and mothers prompted government review and a relatively radical turnaround in policy. However, the emergent model of care has been profoundly influenced by concepts and technologies of monitoring. The use of such technologies as ultrasound scans, electronic foetal monitoring and oxytocic augmentation of labour, generally supported by epidural anaesthesia for pain relief, have accompanied the development of a particular ecological model of birth – often called active management –, which is oriented towards the idea of an obstetric norm. Drawing on analysis of women’s narrative accounts of labour and birth, this article discusses the impact on women’s embodiment in birth, and the sources of information they use about the status of their own bodies, their labour and that of the child. It also illustrates how the impact on women’s experiences of birth may be mediated by a relational model of support, through the provision of caseload midwifery care.

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Este artigo baseia-se em um estudo sobre a reforma na organização dos serviços de maternidade no Reino Unido, que teve como objetivo desenvolver um modelo mais centrado na mulher. Após décadas de fragmentação e despersonalização da assistência, associadas à ascensão do hospital como lugar de parir, a pressão de parteiras e mães obrigou o governo a uma revisão e mudança relativamente radical desta política. No entanto, o modelo emergente de cuidados tem sido profundamente influenciado pelos conceitos e tecnologias de monitoramento. O uso de tecnologias como ultra-sonografia, monitoramento eletrônico fetal e aceleração do parto com ocitocina, geralmente acompanhada de anestesia peridural para alívio da dor, tem promovido o desenvolvimento de um modelo ecológico específico de nascimento – muitas vezes chamado de manejo ativo –, orientado pela idéia de uma norma obstétrica. Com base na análise da narrativa das mulheres, este artigo discute o impacto do modelo assistencial no posicionamento das mulheres frente ao parto e as fontes de informação sobre seus corpos, seus partos e o nascimento da criança que elas utilizam. Ilustra, também, como o impacto nas experiências de parto das mulheres pode ser mediado por um modelo relacional de apoio, mediante a prestação de cuidados de obstetrícia no modelo caseload.
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Este artículo se basa en un estudio sobre la reforma de la organización de los servicios de maternidad en el Reino Unido, que tubo como objetivo desarrollar un modelo más centrado en la mujer. Después de décadas de fragmentación y despersonalización de la atención, asociada con la ascensión del hospital como el lugar de parir, la presión de parteras y madres obligó al gobierno a revisar y hacer un cambio relativamente radical de esta política. Sin embargo, el modelo emergente de atención es profundamente influenciado por los conceptos y las tecnologías de monitoreo. El uso de tecnologías como ecografía, monitorización electrónica fetal y aceleración del parto con oxitocina, por lo general acompañada de anestesia epidural para el alivio del dolor, ha promovido el desarrollo de un modelo ecológico específico de nacimiento – a menudo llamado la manejo de activo –, orientado la idea de una norma obstétrica. Con base en los relatos de las mujeres, este artículo analiza el impacto del modelo de atención en el posicionamiento de las mujeres frente al parto y las fuentes de información acerca de sus cuerpos, sus partos y el nacimiento del niño que ellas utilizan. También ilustra cómo el impacto de las experiencias de parto de las mujeres puede ser mediado por un modelo relacional de apoyo, a través de la prestación de cuidados de partería en el modelo caseload.
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Asunto(s)

Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Proteínas Oncogénicas/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Expresión Génica , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Proteínas Oncogénicas/metabolismo , Complejo de la Endopetidasa Proteasomal , Proteínas Proto-Oncogénicas , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Neoplásico/genética , ARN Neoplásico/metabolismo , Distribución Tisular , Células Tumorales Cultivadas

RESUMEN

Neuroblastoma is a solid tumor that occurs mainly in children. Malignant neuroblastomas have a poor prognosis because conventional chemotherapeutic agents are not very effective. Survivin, a member of the inhibitor of the apoptosis protein family, plays a significant role in cell division, inhibition of apoptosis, and promotion of cell proliferation and invasion. Previous studies found that survivin is highly expressed in some malignant neuroblastomas and is correlated with poor prognosis. The aim of this study was to investigate whether survivin could serve as a potential therapeutic target of human neuroblastoma. We employed RNA interference to reduce survivin expression in the human neuroblastoma SH-SY5Y cell line and analyzed the effect of RNA interference on cell proliferation and invasion in vitro and in vivo. RNA interference of survivin led to a significant decrease in invasiveness and proliferation and increased apoptosis in SH-SY5Y cells in vitro. RNA interference of survivin inhibited tumor growth in vivo by 68±13% (P=0.002) and increased the number of apoptotic cells by 9.8±1.2% (P=0.001) compared with negative small interfering RNA (siRNA) treatment controls. Moreover, RNA interference of survivin inhibited the formation of lung metastases by 92% (P=0.002) and reduced microvascular density by 60% (P=0.0003). Survivin siRNA resulted in significant downregulation of survivin mRNA and protein expression both in vitro and in vivo compared with negative siRNA treatment controls. RNA interference of survivin was found to be a potent inhibitor of SH-SY5Y tumor growth and metastasis formation. These results support further clinical development of RNA interference of survivin as a treatment of neuroblastoma and other cancer types.

Asunto(s)

Animales , Humanos , Apoptosis/efectos de los fármacos , Inhibidores de Cisteína Proteinasa/farmacología , Proteínas Inhibidoras de la Apoptosis/efectos de los fármacos , Neoplasias Pulmonares/secundario , Neuroblastoma/patología , ARN Interferente Pequeño/farmacología , Antineoplásicos/farmacología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Regulación hacia Abajo/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Inmunohistoquímica , Etiquetado Corte-Fin in Situ , Proteínas Inhibidoras de la Apoptosis/genética , Proteínas Inhibidoras de la Apoptosis/metabolismo , Ratones Desnudos , Invasividad Neoplásica , Neuroblastoma/secundario , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , ARN Neoplásico/efectos de los fármacos , ARN Neoplásico/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto

RESUMEN

Neuroblastoma is a solid tumor that occurs mainly in children. Malignant neuroblastomas have a poor prognosis because conventional chemotherapeutic agents are not very effective. Survivin, a member of the inhibitor of the apoptosis protein family, plays a significant role in cell division, inhibition of apoptosis, and promotion of cell proliferation and invasion. Previous studies found that survivin is highly expressed in some malignant neuroblastomas and is correlated with poor prognosis. The aim of this study was to investigate whether survivin could serve as a potential therapeutic target of human neuroblastoma. We employed RNA interference to reduce survivin expression in the human neuroblastoma SH-SY5Y cell line and analyzed the effect of RNA interference on cell proliferation and invasion in vitro and in vivo. RNA interference of survivin led to a significant decrease in invasiveness and proliferation and increased apoptosis in SH-SY5Y cells in vitro. RNA interference of survivin inhibited tumor growth in vivo by 68 ± 13% (P=0.002) and increased the number of apoptotic cells by 9.8 ± 1.2% (P=0.001) compared with negative small interfering RNA (siRNA) treatment controls. Moreover, RNA interference of survivin inhibited the formation of lung metastases by 92% (P=0.002) and reduced microvascular density by 60% (P=0.0003). Survivin siRNA resulted in significant downregulation of survivin mRNA and protein expression both in vitro and in vivo compared with negative siRNA treatment controls. RNA interference of survivin was found to be a potent inhibitor of SH-SY5Y tumor growth and metastasis formation. These results support further clinical development of RNA interference of survivin as a treatment of neuroblastoma and other cancer types.

Asunto(s)

Apoptosis/efectos de los fármacos , Inhibidores de Cisteína Proteinasa/farmacología , Proteínas Inhibidoras de la Apoptosis/efectos de los fármacos , Neoplasias Pulmonares/secundario , Neuroblastoma/patología , ARN Interferente Pequeño/farmacología , Animales , Antineoplásicos/farmacología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Regulación hacia Abajo/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Inmunohistoquímica , Etiquetado Corte-Fin in Situ , Proteínas Inhibidoras de la Apoptosis/genética , Proteínas Inhibidoras de la Apoptosis/metabolismo , Ratones Desnudos , Invasividad Neoplásica , Neuroblastoma/secundario , ARN Neoplásico/efectos de los fármacos , ARN Neoplásico/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Survivin , Ensayos Antitumor por Modelo de Xenoinjerto

RESUMEN

Glioblastoma multiforme (GBM) cells are characterised by their extreme chemoresistance. The activity of multiple-drug resistance (MDR) transporters that extrude antitumor drugs from cells plays the most important role in this phenomenon. To date, the mechanism controlling the expression and activity of MDR transporters is poorly understood. Activity of the enzyme ecto-5'-nucleotidase (CD73) in tumor cells, which hydrolyses AMP to adenosine, has been linked to immunosuppression and prometastatic effects in breast cancer and to the proliferation of glioma cells. In this study, we identify a high expression of CD73 in surgically resected samples of human GBM. In primary cultures of GBM, inhibition of CD73 activity or knocking down its expression by siRNA reversed the MDR phenotype and cell viability was decreased up to 60% on exposure to the antitumoral drug vincristine. This GBM chemosensitization was caused by a decrease in the expression and activity of the multiple drug associated protein 1 (Mrp1), the most important transporter conferring multiple drug resistance in these cells. Using pharmacological modulators, we have recognized the adenosine A(3) receptor subtype in mediation of the chemoresistant phenotype in these cells. In conclusion, we have determined that the activity of CD73 to trigger adenosine signaling sustains chemoresistant phenotype in GBM cells.

Asunto(s)

5'-Nucleotidasa/metabolismo , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/metabolismo , Glioblastoma/tratamiento farmacológico , Glioblastoma/metabolismo , 5'-Nucleotidasa/antagonistas & inhibidores , 5'-Nucleotidasa/genética , Secuencia de Bases , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Resistencia a Múltiples Medicamentos/fisiología , Resistencia a Antineoplásicos/fisiología , Glioblastoma/genética , Glioblastoma/patología , Humanos , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/genética , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Neoplásico/genética , ARN Neoplásico/metabolismo , ARN Interferente Pequeño/genética , Receptor de Adenosina A3/metabolismo , Transducción de Señal , Vincristina/farmacología

RESUMEN

Dietary soy is thought to be cancer-preventive; however, the beneficial effects of soy on established breast cancer is controversial. We recently demonstrated that dietary daidzein or combined soy isoflavones (genistein, daidzein, and glycitein) increased primary mammary tumor growth and metastasis. Cancer-promoting molecules, including eukaryotic protein synthesis initiation factors (eIF) eIF4G and eIF4E, were up-regulated in mammary tumors from mice that received dietary daidzein. Herein, we show that increased eIF expression in tumor extracts of mice after daidzein diets is associated with protein expression of mRNAs with internal ribosome entry sites (IRES) that are sensitive to eIF4E and eIF4G levels. Results with metastatic cancer cell lines show that some of the effects of daidzein in vivo can be recapitulated by the daidzein metabolite equol. In vitro, equol, but not daidzein, up-regulated eIF4G without affecting eIF4E or its regulator, 4E-binding protein (4E-BP), levels. Equol also increased metastatic cancer cell viability. Equol specifically increased the protein expression of IRES containing cell survival and proliferation-promoting molecules and up-regulated gene and protein expression of the transcription factor c-Myc. Moreover, equol increased the polysomal association of mRNAs for p 120 catenin and eIF4G. The elevated eIF4G in response to equol was not associated with eIF4E or 4E-binding protein in 5' cap co-capture assays or co-immunoprecipitations. In dual luciferase assays, IRES-dependent protein synthesis was increased by equol. Therefore, up-regulation of eIF4G by equol may result in increased translation of pro-cancer mRNAs with IRESs and, thus, promote cancer malignancy.

Asunto(s)

Neoplasias de la Mama/metabolismo , Equol/efectos adversos , Factor 4G Eucariótico de Iniciación/biosíntesis , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Glycine max/química , Fitoestrógenos/efectos adversos , Biosíntesis de Proteínas/efectos de los fármacos , Animales , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Línea Celular Tumoral , Suplementos Dietéticos/efectos adversos , Equol/química , Equol/farmacología , Factor 4E Eucariótico de Iniciación/biosíntesis , Factor 4E Eucariótico de Iniciación/genética , Factor 4G Eucariótico de Iniciación/genética , Femenino , Regulación Neoplásica de la Expresión Génica/genética , Humanos , Isoflavonas/efectos adversos , Isoflavonas/farmacología , Ratones , Ratones Desnudos , Trasplante de Neoplasias , Fitoestrógenos/química , Fitoestrógenos/farmacología , Biosíntesis de Proteínas/genética , Proteínas Proto-Oncogénicas c-myc/biosíntesis , Proteínas Proto-Oncogénicas c-myc/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Neoplásico/genética , ARN Neoplásico/metabolismo , Trasplante Heterólogo , Regulación hacia Arriba/efectos de los fármacos , Regulación hacia Arriba/genética

RESUMEN

Considering that stimulation of melanogenesis may lead to alterations of cellular responses, besides melanin production, our main goal was to study the cellular effects of melanogenesis stimulation of B16-F10 melanoma cells. Our results show increased levels of the reactive oxygen species after 15 h of melanogenesis stimulation. Following 48 h of melanogenesis stimulation, proliferation was inhibited (by induction of cell cycle arrest in the G1 phase) and the expression levels of p21 mRNA were increased. In addition, melanogenesis stimulation did not induce cellular senescence. Proteomic analysis demonstrated the involvement of proteins from other pathways besides those related to the cell cycle, including protein disulfide isomerase A3, heat-shock protein 70, and fructose biphosphate aldolase A (all up-regulated), and lactate dehydrogenase (down-regulated). In RT-qPCR experiments, the levels of pyruvate kinase M2 mRNA dropped, whereas the levels of ATP synthase (beta-F1) mRNA increased. These data indicate that melanogenesis stimulation of B16-F10 cells leads to alterations in metabolism and cell cycle progression that may contribute to an induction of cell quiescence, which may provide a mechanism of resistance against cellular injury promoted by melanin synthesis.

Asunto(s)

Melaninas/biosíntesis , Melanoma Experimental/metabolismo , Melanoma Experimental/patología , Cloruro de Amonio/farmacología , Animales , Apoptosis , Ciclo Celular/efectos de los fármacos , Ciclo Celular/fisiología , Proliferación Celular , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Puntos de Control de la Fase G1 del Ciclo Celular , Expresión Génica , Genes Supresores de Tumor , Melanoma Experimental/genética , Ratones , Proteínas de Neoplasias/metabolismo , Proteoma/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Neoplásico/genética , ARN Neoplásico/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Tirosina/farmacología

RESUMEN

In this retrospective study we evaluated the pretherapeutic mRNA expression of the hOCT1 (human organic cation transporter 1) gene in patients with chronic-phase (CP) chronic myeloid leukemia (CML) who varied in terms of their response to imatinib (IM). hOCT1 mRNA was quantified by real-time PCR. Patients were classified as expressing either high (n = 44) or low hOCT1 mRNA (n = 44). The complete cytogenetic response rates observed at 6, 12 and 18 months were 47.7, 84.1 and 91%, respectively, in patients with high hOCT1 mRNA and 47.5, 81.8 and 86.3%, respectively, in patients with low hOCT1 transcripts. The major molecular response rates were not significantly different between patients with high and low hOCT1 mRNA after 6 months of therapy (22.7 vs. 9.1%; p = 0.07), but they were significantly different after 12 months (54.5 vs. 31.8%; p = 0.026) and 18 months (77.2 vs. 56.8%; p = 0.034). Complete molecular responses were observed in 5 patients with low and 17 patients with high hOCT1 mRNA (p = 0.003). The 5-year event-free and overall survival analyses revealed no significant differences between the groups. These data imply that knowledge of the pretherapeutic level of hOCT1 could be a useful marker to predict IM therapy outcome in treatment-naïve CP CML patients.

Asunto(s)

Antineoplásicos/uso terapéutico , Leucemia Mieloide de Fase Crónica/tratamiento farmacológico , Leucemia Mieloide de Fase Crónica/genética , Transportador 1 de Catión Orgánico/genética , Piperazinas/uso terapéutico , Pirimidinas/uso terapéutico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Benzamidas , Biomarcadores de Tumor/genética , Supervivencia sin Enfermedad , Femenino , Expresión Génica , Humanos , Mesilato de Imatinib , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Neoplásico/genética , ARN Neoplásico/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , Inducción de Remisión , Estudios Retrospectivos , Factores de Tiempo , Resultado del Tratamiento , Adulto Joven

RESUMEN

microRNA expression signatures can differentiate normal and breast cancer tissues and can define specific clinico-pathological phenotypes in breast tumors. In order to further evaluate the microRNA expression profile in breast cancer, we analyzed the expression of 667 microRNAs in 29 tumors and 21 adjacent normal tissues using TaqMan Low-density arrays. 130 miRNAs showed significant differential expression (adjusted P value = 0.05, Fold Change = 2) in breast tumors compared to the normal adjacent tissue. Importantly, the role of 43 of these microRNAs has not been previously reported in breast cancer, including several evolutionary conserved microRNA*, showing similar expression rates to that of their corresponding leading strand. The expression of 14 microRNAs was replicated in an independent set of 55 tumors. Bioinformatic analysis of mRNA targets of the altered miRNAs, identified oncogenes like ERBB2, YY1, several MAP kinases, and known tumor-suppressors like FOXA1 and SMAD4. Pathway analysis identified that some biological process which are important in breast carcinogenesis are affected by the altered microRNA expression, including signaling through MAP kinases and TP53 pathways, as well as biological processes like cell death and communication, focal adhesion and ERBB2-ERBB3 signaling. Our data identified the altered expression of several microRNAs whose aberrant expression might have an important impact on cancer-related cellular pathways and whose role in breast cancer has not been previously described.

Asunto(s)

Neoplasias de la Mama/genética , MicroARNs/genética , ARN Neoplásico/genética , Adulto , Anciano , Mama/metabolismo , Neoplasias de la Mama/metabolismo , Biología Computacional , Secuencia Conservada , Quinasas MAP Reguladas por Señal Extracelular/genética , Femenino , Perfilación de la Expresión Génica , Genes Supresores de Tumor , Humanos , MicroARNs/metabolismo , Persona de Mediana Edad , Oncogenes , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Neoplásico/metabolismo , Receptores de Estrógenos/metabolismo , Receptores de Progesterona/metabolismo

RESUMEN

Osteopontin splicing isoforms (OPN-SI) present differential expression patterns and specific tumor roles. Our aims were to characterize OPN-SI expression in prostate cancer (PCa) and benign prostate hyperplasia (BPH) tissues, besides evaluating their potential as biomarkers for PCa diagnosis and prognostic implications. Prostatic tissue specimens were obtained from 40 PCa and 30 benign prostate hyperplasia (BPH) patients. Quantitative real time PCR (qRT-PCR) was used to measure OPN-SI mRNA expression. Immunohistochemical analysis was performed using an anti-OPNc polyclonal antibody. Biostatistical analyses evaluated the association of OPN-SI and total Prostate Specific Antigen (PSA) serum levels with clinical and pathological data. PCa tissue samples presented significantly higher levels of OPNa, OPNb and OPNc transcripts (p<0.01) than in BPH specimens. OPN-SI mRNA expression were positively correlated with Gleason Score (p<0.01). ROC curves and logistic regression analyses demonstrated that OPN-SI and PSA were able to distinguish PCa from BPH patients (p<0.01). The OPNc isoform was the most upregulated variant and the best marker to distinguish patients' groups, presenting sensitivity and specificity of 90% and 100%, respectively. Immunohistochemistry analysis also demonstrated OPNc upregulation in PCa samples as compared to BPH tissues. OPNcprotein was also strongly stained PCa tissues presenting High Gleason Score. Multivariate analysis indicated that OPNc expression levels above the cut-off value presented a chance 4-fold higher for PCa occurrence. We conclude that OPN-SI were overexpressed in PCa tissues, strongly associated with PCa occurrence and with tumor cell differentiation. Our results suggest OPNc splicing isoform as an important biomarker contributing to improve PCa diagnosis and prognosis, besides providing insights into early steps of PCa carcinogenesis.

Asunto(s)

Osteopontina/genética , Hiperplasia Prostática/genética , Neoplasias de la Próstata/genética , Empalme del ARN/genética , ARN Mensajero/genética , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos , Biomarcadores de Tumor/sangre , Diferenciación Celular , Diagnóstico Diferencial , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Valor Predictivo de las Pruebas , Pronóstico , Hiperplasia Prostática/diagnóstico , Neoplasias de la Próstata/diagnóstico , ARN Mensajero/metabolismo , ARN Neoplásico/genética , ARN Neoplásico/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , Sensibilidad y Especificidad

RESUMEN

AIMS: This study aimed to evaluate the copy number alteration on 2q24, its association with ACVR1 transcript expression and the prognostic value of these data in head and neck squamous cell carcinomas. METHODS AND RESULTS: Twenty-eight samples of squamous cell carcinoma were evaluated by fluorescence in situ hybridization (FISH) using the probes RP11-546J1 (2q24) and RP11-21P18 (internal control). Significant gains at 2q24 were detected in most cases at frequencies varying from 3 to 35%. ACVR1 gains and amplifications were associated with longer overall survival (P = 0.022). ACVR1 mRNA expression analysis in 78 cases revealed overexpression in 44% (34 of 78) of these tumours, suggesting that gene copy number alterations could be involved in gene overexpression. In laryngeal carcinomas, overexpression of ACVR1 mRNA levels was associated with longer overall survival (P = 0.013). Multivariate analysis revealed that ACVR1 is an independent prognostic marker in laryngeal carcinomas (P = 0.012, hazard ratio = 0.165, 95% confidence interval =0.041-0.668). CONCLUSIONS: These findings suggest that copy number alterations at 2q24 can be involved in ACVR1 overexpression, which is associated with longer overall survival in laryngeal carcinomas. To our knowledge, this is the first report indicating the relevance of ACVR1 expression in head and neck cancers.

Asunto(s)

Receptores de Activinas Tipo I/genética , Carcinoma de Células Escamosas/genética , Dosificación de Gen , Neoplasias de Cabeza y Cuello/genética , Anciano , Secuencia de Bases , Carcinoma de Células Escamosas/patología , Cromosomas Humanos Par 2/genética , Femenino , Neoplasias de Cabeza y Cuello/patología , Humanos , Hibridación Fluorescente in Situ , Estimación de Kaplan-Meier , Neoplasias Laríngeas/genética , Neoplasias Laríngeas/patología , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/genética , Neoplasias de la Boca/patología , Neoplasias Faríngeas/genética , Neoplasias Faríngeas/patología , Pronóstico , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Neoplásico/genética , ARN Neoplásico/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Regulación hacia Arriba

RESUMEN

Subcutaneous Ehrlich tumor-bearing mice were treated with in situ inoculation of a beta-glucan-rich extract of Agaricus brasiliensis (ATF), which reduced tumor growth. Histopathological analysis showed that the tumor masses of control mice (Ehr) presented giant tumor cells and many mitotic figures whereas the tumor tissue obtained from ATF-treated animals (Ehr-ATF) presented a lower frequency of both mitotic and giant cells, associated with a higher frequency of apoptotic cells than Ehr. Analysis of the lymphoproliferative activity of spleen cells showed that the treatment had a suppressive rather than a stimulatory effect. Spleen cells of the Ehr group produced higher in vitro levels of IL-10 than normal controls and this occurrence was partially avoided by treatment with ATF. Analysis of cytokine production by tumor-infiltrating cells (ELISpot) showed that ATF induced a higher number of IFN-gamma-producing cells at 7 and 14days as well as reduction of IL-10-secreting cells at the latter time. Confocal microscopy analysis showed higher intensity of labeling of CD4+ and Mac-3+ cells in ATF-treated mice. Analysis of in situ expression of angiogenic growth factors showed a slight decrease of FGF-2 mRNA in Ehr-ATF animals (7th day) but not of VEGF-A or TGF-beta expression. This fraction could not directly lyse either lymphocytes or tumor cells and we speculate that antitumor effect of ATF could be due to induction of a selective migration of immunocompetent cells from the spleen to the tumor site and to the switch of cytokine production.

Asunto(s)

Agaricus/química , Carcinoma de Ehrlich/tratamiento farmacológico , Carcinoma de Ehrlich/inmunología , Interleucina-10/biosíntesis , Polisacáridos/farmacología , Proteínas Angiogénicas/genética , Animales , Carcinoma de Ehrlich/genética , Carcinoma de Ehrlich/patología , Citocinas/biosíntesis , Técnicas In Vitro , Interferón gamma/biosíntesis , Activación de Linfocitos/efectos de los fármacos , Linfocitos Infiltrantes de Tumor/efectos de los fármacos , Linfocitos Infiltrantes de Tumor/patología , Espectroscopía de Resonancia Magnética , Masculino , Ratones , Ratones Endogámicos BALB C , Estructura Molecular , Polisacáridos/química , Polisacáridos/aislamiento & purificación , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Neoplásico/genética , ARN Neoplásico/metabolismo

RESUMEN

Diffuse infiltrating gliomas are the most common tumors of the central nervous system. Gliomas are classified by the WHO according to their histopathological and clinical characteristics into four classes: grade I (pilocytic astrocytoma), grade II (diffuse astrocytoma), grade III (anaplastic astrocytoma), and grade IV (glioblastoma multiforme). Several genes have already been correlated with astrocytomas, but many others are yet to be uncovered. By analyzing the public SAGE data from 21 patients, comprising low malignant grade astrocytomas and glioblastomas, we found COL6A1 to be differentially expressed, confirming this finding by real time RT-PCR in 66 surgical samples. To the best of our knowledge, COL6A1 has never been described in gliomas. The expression of this gene has significantly different means when normal glia is compared with low-grade astrocytomas (grades I and II) and high-grade astrocytomas (grades III and IV), with a tendency to be greater in higher grade samples, thus rendering it a powerful tumor marker.

Asunto(s)

Astrocitoma/genética , Colágeno Tipo VI/genética , Perfilación de la Expresión Génica , Astrocitoma/patología , Regulación Neoplásica de la Expresión Génica , Humanos , ARN Neoplásico/genética , ARN Neoplásico/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa