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1.
Front Oncol ; 12: 891850, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36052232

RESUMO

Aim: This study investigated the changes in health-related quality of life from diagnosis to 1 year after diagnosis in breast cancer (BC) patients and the influence of clinical, psychological, and sociodemographic variables. An additional aim was to explore the mediating and moderating effects of resilience on changes in health-related quality of life. Methods: A longitudinal population-based study was conducted in southern Sweden. Newly diagnosed BC patients filled in measures of health-related quality of life, resilience, and sociodemographic variables at diagnosis (N = 980) and 1 year post-diagnosis (N = 780). Clinical variables were extracted from the Swedish national breast cancer quality registry. Mixed-model analyses were performed. Results: Most health-related quality of life outcomes declined from diagnosis to 1 year post-diagnosis. Role limitations due to emotional problems remained the same, whereas mental health improved. Lower health-related quality of life outcomes were associated with symptomatic detection and axillary dissection. Patients with a higher TNM stage and histologic grade and estrogen receptor (ER)-negative and human epidermal growth factor 2 (HER2)-positive status, who received chemotherapy, antibody therapy, or bisphosphonate therapy, had a steeper decline in outcomes. Changes in resilience were positively associated with all outcomes but did not mediate or moderate changes in any. Resilience at baseline moderated changes in bodily pain, vitality, and mental health, with higher baseline resilience being associated with a steeper decline, possibly due to floor or ceiling effects. Patients with lower socioeconomic status, educational level, and older age had a lower health-related quality of life. Conclusion: Physical health-related quality of life among breast cancer patients declined 1 year post-diagnosis, whereas mental health-related quality of life improved. Low resilient patients may be especially vulnerable at diagnosis. Biopsychosocial assessment at diagnosis can help identify patients who may require additional support. A multidimensional treatment plan should be started early to help overcome the problems in everyday activities.

2.
Genet Med ; 24(1): 157-169, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34906508

RESUMO

PURPOSE: More than half of the familial cutaneous melanomas have unknown genetic predisposition. This study aims at characterizing a novel melanoma susceptibility gene. METHODS: We performed exome and targeted sequencing in melanoma-prone families without any known melanoma susceptibility genes. We analyzed the expression of candidate gene DENND5A in melanoma samples in relation to pigmentation and UV signature. Functional studies were carried out using microscopic approaches and zebrafish model. RESULTS: We identified a novel DENND5A truncating variant that segregated with melanoma in a Swedish family and 2 additional rare DENND5A variants, 1 of which segregated with the disease in an American family. We found that DENND5A is significantly enriched in pigmented melanoma tissue. Our functional studies show that loss of DENND5A function leads to decrease in melanin content in vitro and pigmentation defects in vivo. Mechanistically, harboring the truncating variant or being suppressed leads to DENND5A losing its interaction with SNX1 and its ability to transport the SNX1-associated vesicles from melanosomes. Consequently, untethered SNX1-premelanosome protein and redundant tyrosinase are redirected to lysosomal degradation by default, causing decrease in melanin content. CONCLUSION: Our findings provide evidence of a physiological role of DENND5A in the skin context and link its variants to melanoma susceptibility.


Assuntos
Fatores de Troca do Nucleotídeo Guanina/genética , Melanoma , Neoplasias Cutâneas , Animais , Predisposição Genética para Doença , Humanos , Melanoma/genética , Melanossomas , Monofenol Mono-Oxigenase/metabolismo , Neoplasias Cutâneas/genética , Nexinas de Classificação , Sequenciamento do Exoma , Peixe-Zebra/genética
3.
Methods Mol Biol ; 2324: 219-236, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34165718

RESUMO

Several recent studies support a functional role for pseudogenes, a copy of a parent gene that has lost protein-coding potential, which was for a long time thought to represent only "junk" DNA. Several hundreds of pseudogenes have now been reported as transcribed RNAs in a large variety of tissues and tumor types. Most studies have focused on pseudogenes expressed in sense direction, relative to their protein-coding gene counterpart, but some reports suggest that pseudogenes can be also transcribed as antisense RNAs (asRNAs). Key regulatory genes, such as PTEN and OCT4, have in fact been reported to be under the regulation of pseudogene-expressed asRNAs. Here, we review what is known about pseudogene-expressed asRNAs, we discuss the functional role that these transcripts may have in gene regulation and we summarize the techniques that are available to study them.


Assuntos
Regulação da Expressão Gênica/genética , Pseudogenes/genética , RNA Antissenso/genética , RNA não Traduzido/genética , Animais , Imunoprecipitação da Cromatina/métodos , Técnicas de Silenciamento de Genes , Estudo de Associação Genômica Ampla/métodos , Humanos , Lymnaea/genética , Óxido Nítrico Sintase Tipo I/genética , Fator 3 de Transcrição de Octâmero/genética , PTEN Fosfo-Hidrolase/genética , Estabilidade de RNA , Transcrição Gênica
4.
Sci Rep ; 11(1): 11023, 2021 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-34040017

RESUMO

BRAF inhibitors (BRAFi) selectively target oncogenic BRAFV600E/K and are effective in 80% of advanced cutaneous malignant melanoma cases carrying the V600 mutation. However, the development of drug resistance limits their clinical efficacy. Better characterization of the underlying molecular processes is needed to further improve treatments. We previously demonstrated that transcription of PTEN is negatively regulated by the PTEN pseudogene antisense RNA, PTENP1-AS, and here we investigated the impact of this transcript on clinical outcome and BRAFi resistance in melanoma. We observed that increased expression levels of PTENP1-AS in BRAFi resistant cells associated with enrichment of EZH2 and H3K27me3 at the PTEN promoter, consequently reducing the expression levels of PTEN. Further, we showed that targeting of the PTENP1-AS transcript sensitized resistant cells to BRAFi treatment and that high expression of PTENP1-AS in stage III melanoma correlated with poor survival. Collectively, the data presented here show that PTENP1-AS is a promising target for re-sensitizing cells to BRAFi and also a possible prognostic marker for clinical outcome in stage III melanoma.


Assuntos
Melanoma , Proteínas Proto-Oncogênicas B-raf , Neoplasias Cutâneas , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Humanos , Inibidores de Proteínas Quinases/farmacologia , Transdução de Sinais/efeitos dos fármacos , Vemurafenib/farmacologia , Melanoma Maligno Cutâneo
5.
Cancer Manag Res ; 12: 12041-12051, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33269004

RESUMO

PURPOSE: Psychological resilience appears to be an important influencing factor in various aspects of health-related quality of life (HRQoL) in a context of adversity, eg, being informed of a cancer diagnosis. The purpose was to investigate psychological resilience and HRQoL in Swedish women with newly diagnosed breast cancer in relation to demographic and clinicopathological characteristics. METHODS: A population-based cross-sectional study was conducted including 517 women with breast cancer in the South Swedish Health Care Region. Participants were enrolled at the time of consultation for the diagnosis. Psychological resilience was assessed with the Connor-Davidson Resilience Scale 25 (CD-RISC25), and HRQoL was assessed with the Short Form Health Survey. The participants responded to questions regarding demographic variables. Clinicopathological data were collected from the Swedish National Quality Register for Breast Cancer. RESULTS: The mean score for psychological resilience was 70.6, identifying 15% of included patients with a score lower than 58 (-1 standard deviation). The study cohort had significantly lower mean scores for several aspects of HRQoL compared with Swedish normative data. Regression analyses demonstrated that psychological resilience was significantly associated with all domains of HRQoL after adjustment for demographic and clinicopathological factors. CONCLUSION: Higher levels of psychological resilience were significantly related to higher levels of HRQoL in Swedish women with newly diagnosed breast cancer and no modifying factor was identified. The assessment of psychological resilience at the time of breast cancer diagnosis might allow for early identification of women in need of more intense psychosocial support. Future studies are needed to identify a clinically relevant threshold of the CD-RISC25.

6.
BMC Cancer ; 18(1): 789, 2018 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-30081937

RESUMO

BACKGROUND: Individual patients differ in their psychological response when receiving a cancer diagnosis, in this case breast cancer. Given the same disease burden, some patients master the situation well, while others experience a great deal of stress, depression and lowered quality of life. Patients with high psychological resilience are likely to experience fewer stress reactions and better adapt to and manage the life threat and the demanding treatment that follows the diagnosis. If this phenomenon of mastering difficult situations is reflected also in biomolecular processes is not much studied, nor has its capacity for impacting the cancer prognosis been addressed. This project specifically aims, for the first time, to investigate how a breast cancer patient's psychological resilience is coupled to biomolecular parameters using advanced "omics" and, as a secondary aim, whether it relates to prognosis and quality of life one year after diagnosis. METHOD: The study population consists of newly diagnosed breast cancer patients enrolled in the Sweden Cancerome Analysis Network - Breast (SCAN-B) at four hospitals in Sweden. At the time of cancer diagnosis, the patient fills out the standardized method to measure psychological resilience, the "Connor-Davidson Resilience scale" (CD-RISC), the quality of life measure SF-36, as well as providing social and socioeconomic variables. In addition, one blood sample is collected. At the one-year follow-up, the patient will be subjected to the same assessments, and we also collect information regarding smoking, exercise habits, and BMI, as well as patients' trust in the treatment and their satisfaction with the care and treatment. DISCUSSION: This explorative hypothesis-generating project will pave the way for larger validation studies, potentially leading to a standardized method of measuring psychological resilience as an important parameter in cancer care. Revealing the body-mind interaction, in terms of psychological resilience and quality of life, will herald the development of truly personalized psychosocial care and cancer intervention treatment strategies. TRIAL REGISTRATION: This is a retrospectively registered trial at ClinicalTrials.gov, ID: NCT03430492 on February 6, 2018.


Assuntos
Biomarcadores Tumorais/sangue , Neoplasias da Mama/sangue , Neoplasias da Mama/psicologia , Resiliência Psicológica , Adaptação Psicológica , Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Neoplasias da Mama/terapia , Efeitos Psicossociais da Doença , Feminino , Perfilação da Expressão Gênica , Genômica/métodos , Humanos , Estudos Multicêntricos como Assunto , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Proteômica , Qualidade de Vida , Inquéritos e Questionários , Suécia , Fatores de Tempo
7.
Cell Death Dis ; 9(7): 736, 2018 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-29970884

RESUMO

The microRNA-34a is a well-studied tumor suppressor microRNA (miRNA) and a direct downstream target of TP53 with roles in several pathways associated with oncogenesis, such as proliferation, cellular growth, and differentiation. Due to its broad tumor suppressive activity, it is not surprising that miR34a expression is altered in a wide variety of solid tumors and hematological malignancies. However, the mechanisms by which miR34a is regulated in these cancers is largely unknown. In this study, we find that a long noncoding RNA transcribed antisense to the miR34a host gene, is critical for miR34a expression and mediation of its cellular functions in multiple types of human cancer. We name this long noncoding RNA lncTAM34a, and characterize its ability to facilitate miR34a expression under different types of cellular stress in both TP53-deficient and wild-type settings.


Assuntos
MicroRNAs/metabolismo , RNA Antissenso/fisiologia , Western Blotting , Ciclo Celular/genética , Ciclo Celular/fisiologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Proliferação de Células/fisiologia , Imunoprecipitação da Cromatina , Biologia Computacional , Dano ao DNA/genética , Dano ao DNA/fisiologia , Regulação Neoplásica da Expressão Gênica/genética , Regulação Neoplásica da Expressão Gênica/fisiologia , Genes Supressores de Tumor/fisiologia , Humanos , MicroRNAs/genética , Regiões Promotoras Genéticas/genética , RNA Antissenso/genética , Espectrometria de Massas em Tandem
8.
Proc Natl Acad Sci U S A ; 114(37): 9942-9947, 2017 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-28847966

RESUMO

RNA has been found to interact with chromatin and modulate gene transcription. In human cells, little is known about how long noncoding RNAs (lncRNAs) interact with target loci in the context of chromatin. We find here, using the phosphatase and tensin homolog (PTEN) pseudogene as a model system, that antisense lncRNAs interact first with a 5' UTR-containing promoter-spanning transcript, which is then followed by the recruitment of DNA methyltransferase 3a (DNMT3a), ultimately resulting in the transcriptional and epigenetic control of gene expression. Moreover, we find that the lncRNA and promoter-spanning transcript interaction are based on a combination of structural and sequence components of the antisense lncRNA. These observations suggest, on the basis of this one example, that evolutionary pressures may be placed on RNA structure more so than sequence conservation. Collectively, the observations presented here suggest a much more complex and vibrant RNA regulatory world may be operative in the regulation of gene expression.


Assuntos
PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/fisiologia , Cromatina/genética , Montagem e Desmontagem da Cromatina , DNA Metiltransferase 3A , Éxons , Células HEK293 , Humanos , Simulação de Dinâmica Molecular , Conformação de Ácido Nucleico , Regiões Promotoras Genéticas/genética , Pseudogenes , Elementos Reguladores de Transcrição/genética , Elementos Reguladores de Transcrição/fisiologia , Análise de Sequência de RNA/métodos , Homologia de Sequência
9.
Surg Obes Relat Dis ; 12(4): 882-890, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27134198

RESUMO

BACKGROUND: About 20% of adolescents experience substantial mental health problems after bariatric surgery. OBJECTIVES: The aim of this study was to explore differences between adolescents with poor mental health (PMH) 2 years after surgery and those with average/good mental health. SETTING: Three university hospitals in Sweden. METHODS: Mental health and health-related quality of life were assessed in 82 of 88 adolescents (mean age: 16.8 yr, 67% female) at baseline and 1 and 2 years after laparoscopic gastric bypass. Possible associations among mental health, weight, and biochemical outcomes were explored. RESULTS: Two years after surgery 16 (20%) adolescents were identified as having PMH. More symptoms of anxiety and depression and worse mental health at baseline significantly predicted PMH 2 years later. The decline in mental health for the PMH group happened mainly during the second year after surgery. Suicidal ideation was reported in 14% of the total sample 2 years postsurgery and was more frequent in the PMH group. Weight outcomes between groups were comparable at all time points, and physical health was equally improved 2 years after surgery. CONCLUSIONS: Although adolescents with PMH after surgery lose as much weight and have similar improvements in physical health compared with other adolescents, special attention should be given to adolescents who report mental health problems at baseline and follow-up, especially during the second year after gastric bypass. The high prevalence of suicidal ideation in adolescents 2 years after bariatric surgery is another indication that longer follow-up is necessary.


Assuntos
Derivação Gástrica/psicologia , Laparoscopia/psicologia , Transtornos Mentais/etiologia , Obesidade Infantil/psicologia , Adolescente , Transtornos de Ansiedade/etiologia , Biomarcadores/metabolismo , Transtorno Depressivo/etiologia , Emoções , Feminino , Derivação Gástrica/efeitos adversos , Nível de Saúde , Hospitalização , Humanos , Laparoscopia/efeitos adversos , Masculino , Obesidade Infantil/cirurgia , Complicações Pós-Operatórias/psicologia , Prognóstico , Qualidade de Vida , Autoimagem , Ideação Suicida , Suécia
10.
Curr Top Microbiol Immunol ; 394: 111-26, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-25982975

RESUMO

Pseudogenes have for long been considered as non-functional relics littering the human genome. Only now, it is becoming apparent that many pseudogenes are transcribed into long noncoding RNAs, some with proven biological functions. Here, we review the current knowledge of pseudogenes and their widespread functional properties with an emphasis on pseudogenes that have been functionally investigated in greater detail. Pseudogenes are emerging as a novel class of long noncoding RNAs functioning, for example, through microRNA sponging and chromatin remodeling. The examples discussed herein underline that pseudogene-encoded RNAs are important regulatory molecules involved in diseases such as cancer.


Assuntos
Pseudogenes/fisiologia , Proteína HMGA1a/genética , Humanos , Neoplasias/genética , Fator 3 de Transcrição de Octâmero/genética , PTEN Fosfo-Hidrolase/genética , RNA Longo não Codificante/fisiologia
11.
Obesity (Silver Spring) ; 23(10): 1966-72, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26227556

RESUMO

OBJECTIVE: This study aimed to evaluate changes in mental health over 2 years in adolescents undergoing gastric bypass. METHODS: Eighty-eight adolescents (65% girls) aged 13 to 18 years were assessed at baseline and 1 and 2 years after surgery. Generic and obesity-specific questionnaires were used to evaluate outcomes in mental health, also in relation to age- and gender-specific norms. RESULTS: Symptoms of anxiety (P = 0.001), depression (P = 0.001), anger (P = 0.001), and disruptive behavior (P = 0.022) were significantly reduced at 2 years after surgery, as were obesity-related problems (P < 0.001). Self-esteem (P < 0.001), self-concept (P < 0.001), and overall mood (P = 0.025) improved significantly. Improvements were mainly observed during the first year after surgery. The second year was characterized by stabilization. Symptoms of anxiety, depression, anger, disruptive behavior, and self-concept were at normative levels after surgery. However, 19% of the adolescents had depressive symptoms in the clinical range. CONCLUSIONS: A substantial improvement in mental health in adolescents over the first 2 years after gastric bypass was found. Most adolescents had a level of mental health and self-concept similar to norms, but a marked subgroup showed substantial depressive symptoms 2 years after surgery.


Assuntos
Ansiedade/etiologia , Depressão/etiologia , Derivação Gástrica/psicologia , Obesidade Mórbida/cirurgia , Adaptação Psicológica , Adolescente , Comportamento do Adolescente/psicologia , Ansiedade/psicologia , Depressão/psicologia , Feminino , Seguimentos , Derivação Gástrica/efeitos adversos , Humanos , Masculino , Autoimagem , Inquéritos e Questionários , Resultado do Tratamento
12.
Int J Cancer ; 136(4): E51-61, 2015 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-25156627

RESUMO

The mechanism of multicellular drug resistance, defined as the reduced efficacy of chemotherapeutic drugs in solid tumors is incompletely understood. Here we report that colon carcinoma cells cultured as 3D microtissues (spheroids) display dramatic increases in the expression of a subset of type I interferon-(IFN)-stimulated genes (ISGs). A similar gene signature was associated previously with resistance to radiation and chemotherapy, prompting us to examine the underlying biological mechanisms. Analysis of spheroids formed by different tumor cell lines and studies using knock-down of gene expression showed that cell crowding leads to the induction of IFN regulatory factor-9 (IRF9) which together with STAT2 and independently of IFNs, is necessary for ISG upregulation. Increased expression of IRF9 alone was sufficient to induce the ISG subset in monolayer cells and to confer increased resistance to clinically used cytotoxic drugs. Our data reveal a novel mechanism of regulation of a subset of ISGs, leading to drug resistance in solid tumors.


Assuntos
Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos , Fator Gênico 3 Estimulado por Interferon, Subunidade gama/genética , Apoptose , Comunicação Celular , Sobrevivência Celular/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Células HCT116 , Humanos , Fator Gênico 3 Estimulado por Interferon, Subunidade gama/metabolismo , Interferons/fisiologia , Fator de Transcrição STAT2/metabolismo , Ativação Transcricional
13.
Faraday Discuss ; 171: 57-80, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25290160

RESUMO

This paper gives an account of our progress towards performing femtosecond time-resolved photoelectron diffraction on gas-phase molecules in a pump-probe setup combining optical lasers and an X-ray free-electron laser. We present results of two experiments aimed at measuring photoelectron angular distributions of laser-aligned 1-ethynyl-4-fluorobenzene (C(8)H(5)F) and dissociating, laser-aligned 1,4-dibromobenzene (C(6)H(4)Br(2)) molecules and discuss them in the larger context of photoelectron diffraction on gas-phase molecules. We also show how the strong nanosecond laser pulse used for adiabatically laser-aligning the molecules influences the measured electron and ion spectra and angular distributions, and discuss how this may affect the outcome of future time-resolved photoelectron diffraction experiments.

14.
Cell Res ; 24(11): 1284-5, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25104732

RESUMO

New findings bring to light a previously unappreciated mechanism involved in the regulation of the oncoprotein MYC. Interesting observations find that the long noncoding RNA (lncRNA) PVT1 is active in controlling levels of MYC through regulation of MYC protein stability.


Assuntos
Variações do Número de Cópias de DNA/genética , Amplificação de Genes/genética , Dosagem de Genes/genética , Genes myc/genética , Proteína Oncogênica p55(v-myc)/genética , RNA Longo não Codificante/genética , Animais , Humanos
15.
Nat Commun ; 5: 4557, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-25080976

RESUMO

The establishment and maintenance of apical-basal cell polarity is essential for the functionality of glandular epithelia. Cell polarity is often lost in advanced tumours correlating with acquisition of invasive and malignant properties. Despite extensive knowledge regarding the formation and maintenance of polarity, the mechanisms that deregulate polarity in metastasizing cells remain to be fully characterized. Here we show that AmotL2 expression correlates with loss of tissue architecture in tumours from human breast and colon cancer patients. We further show that hypoxic stress results in activation of c-Fos-dependent expression of AmotL2 leading to loss of polarity. c-Fos/hypoxia-induced p60 AmotL2 interacts with the Crb3 and Par3 polarity complexes retaining them in large vesicles and preventing them from reaching the apical membrane. The resulting loss of polarity potentiates the response to invasive cues in vitro and in vivo in mice. These data provide a molecular mechanism how hypoxic stress deregulates cell polarity during tumour progression.


Assuntos
Neoplasias da Mama/genética , Proteínas de Transporte/genética , Neoplasias do Colo/genética , Regulação Neoplásica da Expressão Gênica , Hipóxia/genética , Proteínas Adaptadoras de Transdução de Sinal , Angiomotinas , Animais , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Células CACO-2 , Proteínas de Transporte/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Polaridade Celular , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Neoplasias do Colo/cirurgia , Feminino , Células HeLa , Humanos , Hipóxia/metabolismo , Hipóxia/patologia , Linfonodos/metabolismo , Linfonodos/patologia , Linfonodos/cirurgia , Glândulas Mamárias Humanas/metabolismo , Glândulas Mamárias Humanas/patologia , Glândulas Mamárias Humanas/cirurgia , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Camundongos SCID , Invasividade Neoplásica , Estadiamento de Neoplasias , Transplante de Neoplasias , Proteínas Proto-Oncogênicas c-fos/genética , Proteínas Proto-Oncogênicas c-fos/metabolismo , Transdução de Sinais , Vesículas Transportadoras/metabolismo
16.
Front Genet ; 5: 234, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25101115

RESUMO

Metastasis is a multistep process beginning with the dissemination of tumor cells from a primary site and leading to secondary tumor development in an anatomically distant location. Although significant progress has been made in understanding the molecular characteristics of metastasis, many questions remain regarding the intracellular mechanisms governing transition through the various metastatic stages. Long non-coding RNAs (lncRNAs) are capable of modulating both transcriptional and post-transcriptional regulation, and thus, coordinating a wide array of diverse cellular processes. Current evidence indicates that lncRNAs may also play a crucial role in the metastatic process through regulation of metastatic signaling cascades as well as interaction with specific metastatic factors. Here we summarize a subset of lncRNAs with proposed roles in metastasis and, when applicable, highlight the mechanism by which they function.

17.
Methods Mol Biol ; 1167: 213-26, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24823780

RESUMO

While long thought to represent only "junk" DNA, several recent studies support a functional role for pseudogenes. Several hundreds of pseudogenes have been reported as transcribed into RNA in a large variety of tissues and tumors. Most studies have focused on pseudogenes expressed in the sense direction, but some reports suggest that pseudogenes can be also transcribed as antisense RNAs (asRNAs). A few examples of key regulatory genes, such as PTEN and OCT4, have in fact been reported to be under the regulation of pseudogene-expressed asRNAs. Here, we review what is known about pseudogene-expressed asRNAs and we discuss the functional role that these transcripts may have in gene regulation. Finally, we discuss some technical challenges when characterising the function of pseudogene asRNAs.


Assuntos
Regulação da Expressão Gênica , Pseudogenes/genética , RNA Antissenso/genética , Perfilação da Expressão Gênica , Estudo de Associação Genômica Ampla , Humanos , RNA Antissenso/metabolismo , Transcrição Gênica
18.
Leuk Lymphoma ; 55(5): 1158-65, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-23841503

RESUMO

Abstract Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous disease, and infectious agents are suspected to be involved in the tumorigenesis of DLBCL. MicroRNAs (miRNAs) are non-coding RNAs modulating protein expression. We compared miRNA expression profiles in lymph node tissues of patients with DLBCL of the activated B-cell like (ABC) type from two geographical areas with different background exposures, Sweden and Egypt. We showed previously that DLBCL tissues of the ABC-type in Swedish patients had a higher expression of signal transducer and activator of transcription 3 (STAT3) compared to Egyptian patients. Here, we analyzed the involvement of miRNAs in STAT3 regulation. miR-1234 was significantly up-regulated in Egyptian patients with DLBCL compared to Swedish patients (p < 0.03). The miR-1234 expression level correlated inversely with the expression of STAT3. The Stat3 protein was down-regulated in cells transfected with miR-1234, suggesting that STAT3 might be a potential target for miR-1234. miR-1234 and STAT3 might be involved in the tumorigenesis of DLBCL of ABC type and possibly associated with environmental background exposure.


Assuntos
Regulação Neoplásica da Expressão Gênica , Linfoma Difuso de Grandes Células B/genética , MicroRNAs/genética , Fator de Transcrição STAT3/genética , Adulto , Idoso , Estudos de Casos e Controles , Linhagem Celular , Análise por Conglomerados , Egito , Feminino , Humanos , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/metabolismo , Linfoma Difuso de Grandes Células B/mortalidade , Masculino , Pessoa de Meia-Idade , Interferência de RNA , Fator de Transcrição STAT3/metabolismo , Suécia , Transcriptoma , Transfecção
19.
Biochim Biophys Acta ; 1840(3): 1063-71, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24184936

RESUMO

BACKGROUND: Recent advances in genomewide studies have revealed the abundance of long non-coding RNAs (lncRNAs) in mammalian transcriptomes. The ENCODE Consortium has elucidated the prevalence of human lncRNA genes, which are as numerous as protein-coding genes. Surprisingly, many lncRNAs do not show the same pattern of high interspecies conservation as protein-coding genes. The absence of functional studies and the frequent lack of sequence conservation therefore make functional interpretation of these newly discovered transcripts challenging. Many investigators have suggested the presence and importance of secondary structural elements within lncRNAs, but mammalian lncRNA secondary structure remains poorly understood. It is intriguing to speculate that in this group of genes, RNA secondary structures might be preserved throughout evolution and that this might explain the lack of sequence conservation among many lncRNAs. SCOPE OF REVIEW: Here, we review the extent of interspecies conservation among different lncRNAs, with a focus on a subset of lncRNAs that have been functionally investigated. The function of lncRNAs is widespread and we investigate whether different forms of functionalities may be conserved. MAJOR CONCLUSIONS: Lack of conservation does not imbue a lack of function. We highlight several examples of lncRNAs where RNA structure appears to be the main functional unit and evolutionary constraint. We survey existing genomewide studies of mammalian lncRNA conservation and summarize their limitations. We further review specific human lncRNAs which lack evolutionary conservation beyond primates but have proven to be both functional and therapeutically relevant. GENERAL SIGNIFICANCE: Pioneering studies highlight a role in lncRNAs for secondary structures, and possibly the presence of functional "modules", which are interspersed with longer and less conserved stretches of nucleotide sequences. Taken together, high-throughput analysis of conservation and functional composition of the still-mysterious lncRNA genes is only now becoming feasible.


Assuntos
Evolução Molecular , RNA Longo não Codificante/química , RNA Longo não Codificante/fisiologia , Animais , Sequência Conservada , Humanos , RNA Antissenso/química , RNA Antissenso/fisiologia , RNA Longo não Codificante/genética
20.
Nat Struct Mol Biol ; 20(4): 440-6, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23435381

RESUMO

PTEN is a tumor-suppressor gene that has been shown to be under the regulatory control of a PTEN pseudogene expressed noncoding RNA, PTENpg1. Here, we characterize a previously unidentified PTENpg1-encoded antisense RNA (asRNA), which regulates PTEN transcription and PTEN mRNA stability. We find two PTENpg1 asRNA isoforms, α and ß. The α isoform functions in trans, localizes to the PTEN promoter and epigenetically modulates PTEN transcription by the recruitment of DNA methyltransferase 3a and Enhancer of Zeste. In contrast, the ß isoform interacts with PTENpg1 through an RNA-RNA pairing interaction, which affects PTEN protein output through changes of PTENpg1 stability and microRNA sponge activity. Disruption of this asRNA-regulated network induces cell-cycle arrest and sensitizes cells to doxorubicin, which suggests a biological function for the respective PTENpg1 expressed asRNAs.


Assuntos
Regulação da Expressão Gênica/fisiologia , PTEN Fosfo-Hidrolase/genética , Biossíntese de Proteínas/fisiologia , Pseudogenes , RNA não Traduzido/fisiologia , Transcrição Gênica/fisiologia , Apoptose/fisiologia , Ciclo Celular/fisiologia , Montagem e Desmontagem da Cromatina , DNA Metiltransferase 3A , Genes Supressores de Tumor , Células HEK293 , Humanos , Regiões Promotoras Genéticas , RNA não Traduzido/genética
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