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1.
Int J Mol Sci ; 25(5)2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38473786

RESUMEN

The MYBL1 gene is a strong transcriptional activator involved in events associated with cancer progression. Previous data show MYBL1 overexpressed in triple-negative breast cancer (TNBC). There are two parts to this study related to further characterizing the MYBL1 gene. We start by characterizing MYBL1 reference sequence variants and isoforms. The results of this study will help in future experiments in the event there is a need to characterize functional variants and isoforms of the gene. In part two, we identify and validate expression and gene-related alterations of MYBL1, VCIP1, MYC and BOP1 genes in TNBC cell lines and patient samples selected from the Breast Invasive Carcinoma TCGA 2015 dataset available at cBioPortal.org. The four genes are located at chromosomal regions 8q13.1 to 8q.24.3 loci, regions previously identified as demonstrating a high percentage of alterations in breast cancer. We identify alterations, including changes in expression, deletions, amplifications and fusions in MYBL1, VCPIP1, BOP1 and MYC genes in many of the same patients, suggesting the panel of genes is involved in coordinated activity in patients. We propose that MYBL1, VCPIP1, MYC and BOP1 collectively be considered as genes associated with the chromosome 8q loci that potentially play a role in TNBC pathogenesis.


Asunto(s)
Carcinoma , Neoplasias de la Mama Triple Negativas , Humanos , Mama , Cromosomas , Isoformas de Proteínas , Proteínas Proto-Oncogénicas , Transactivadores , Proteínas de Unión al ARN
2.
Genes Cancer ; 8(7-8): 659-672, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28966727

RESUMEN

When triple negative breast cancer (TNBC) are analyzed by gene expression profiling different subclasses are identified, at least one characterized by genes related to immune signaling mechanisms supporting the role of these genes in the cancers. In an earlier study we observed differences in TNBC cell lines with respect to their expression of the cytokine IL32. Our analyses showed that certain cell lines expressed higher levels of the cytokine compared to others. Because TNBC are heterogeneous and immune-related genes appear to play a pivotal role in these cancers, we chose to examine the transcriptomes of the different cell lines based on IL32 expression. We performed group analyses of TNBC cell lines demonstrating high IL32 compared to low IL32 levels and identified IL32, GATA3, MYBL1, ETS1, PTX3 and TMEM158 as differentially associated with a subpopulation of TNBC. The six candidate genes were validated experimental and in different patient datasets. The genes distinguished a subset of TNBC from other TNBC, and TNBC from normal, luminal A, luminal B, and HER2 patient samples. The current project serves as a preliminary study in which we outline the discovery and validation of our list of six candidate genes.

3.
BMC Res Notes ; 7: 501, 2014 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-25100201

RESUMEN

BACKGROUND: Triple negative breast cancer (TNBC) and often basal-like cancers are defined as negative for estrogen receptor, progesterone receptor and Her2 gene expression. Over the past few years an incredible amount of data has been generated defining the molecular characteristics of both cancers. The aim of these studies is to better understand the cancers and identify genes and molecular pathways that might be useful as targeted therapies. In an attempt to contribute to the understanding of basal-like/TNBC, we examined the Gene Expression Omnibus (GEO) public datasets in search of genes that might define basal-like/TNBC. The Il32 gene was identified as a candidate. FINDINGS: Analysis of several GEO datasets showed differential expression of IL32 in patient samples previously designated as basal and/or TNBC compared to normal and luminal breast samples. As validation of the GEO results, RNA and protein expression levels were examined using MCF7 and MDA MB231 cell lines and tissue microarrays (TMAs). IL32 gene expression levels were higher in MDA MB231 compared to MCF7. Analysis of TMAs showed 42% of TNBC tissues and 25% of the non-TNBC were positive for IL32, while non-malignant patient samples and all but one hyperplastic tissue sample demonstrated lower levels of IL32 protein expression. CONCLUSION: Data obtained from several publically available GEO datasets showed overexpression of IL32 gene in basal-like/TNBC samples compared to normal and luminal samples. In support of these data, analysis of TMA clinical samples demonstrated a particular pattern of IL32 differential expression. Considered together, these data suggest IL32 is a candidate suitable for further study.


Asunto(s)
Interleucinas/genética , Neoplasias de la Mama Triple Negativas/genética , Línea Celular Tumoral , Bases de Datos Genéticas , Femenino , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Humanos , Inmunohistoquímica , Interleucinas/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Análisis de Matrices Tisulares
4.
Am J Pathol ; 182(2): 529-39, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23219752

RESUMEN

The classic tumor clonal evolution theory postulates that cancers change over time to produce unique molecular subclones within a parent neoplasm, presumably including regional differences in gene expression. More recently, however, this notion has been challenged by studies showing that tumors maintain a relatively stable transcript profile. To examine these competing hypotheses, we microdissected discrete subregions containing approximately 3000 to 8000 cells (500 to 1500 µm in diameter) from ex vivo esophageal squamous cell carcinoma (ESCC) specimens and analyzed transcriptomes throughout three-dimensional tumor space. Overall mRNA profiles were highly similar in all 59 intratumor comparisons, in distinct contrast to the markedly different global expression patterns observed in other dissected cell populations. For example, normal esophageal basal cells contained 1918 and 624 differentially expressed genes at a greater than twofold level (95% confidence level of <5% false positives), compared with normal differentiated esophageal cells and ESCC, respectively. In contrast, intratumor regions had only zero to four gene changes at a greater than twofold level, with most tumor comparisons showing none. The present data indicate that, when analyzed using a standard array-based method at this level of histological resolution, ESCC contains little regional mRNA heterogeneity.


Asunto(s)
Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patología , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/patología , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Heterogeneidad Genética , Carcinoma de Células Escamosas de Esófago , Genes Relacionados con las Neoplasias/genética , Humanos , Microdisección , ARN Mensajero/genética , ARN Mensajero/metabolismo , Transducción de Señal/genética
5.
BMC Res Notes ; 5: 73, 2012 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-22280838

RESUMEN

BACKGROUND: Esophageal squamous cell carcinoma (ESCC), the predominant histological subtype of esophageal cancer, is characterized by high mortality. Previous work identified important mRNA expression differences between normal and tumor cells; however, to date there are limited ex vivo studies examining expression changes occurring during normal esophageal squamous cell differentiation versus those associated with tumorigenesis. In this study, we used a unique tissue microdissection strategy and microarrays to measure gene expression profiles associated with cell differentiation versus tumorigenesis in twelve cases of patient-matched normal basal squamous epithelial cells (NB), normal differentiated squamous epithelium (ND), and squamous cell cancer. Class comparison and pathway analysis were used to compare NB versus tumor in a search for unique therapeutic targets. RESULTS: As a first step towards this goal, gene expression profiles and pathways were evaluated. Overall, ND expression patterns were markedly different from NB and tumor; whereas, tumor and NB were more closely related. Tumor showed a general decrease in differentially expressed genes relative to NB as opposed to ND that exhibited the opposite trend. FSH and IgG networks were most highly dysregulated in normal differentiation and tumorigenesis, respectively. DNA repair pathways were generally elevated in NB and tumor relative to ND indicating involvement in both normal and pathological growth. PDGF signaling pathway and 12 individual genes unique to the tumor/NB comparison were identified as therapeutic targets, and 10 associated ESCC gene-drug pairs were identified. We further examined the protein expression level and the distribution patterns of four genes: ODC1, POSTN, ASPA and IGF2BP3. Ultimately, three genes (ODC1, POSTN, ASPA) were verified to be dysregulated in the same pattern at both the mRNA and protein levels. CONCLUSIONS: These data reveal insight into genes and molecular pathways mediating ESCC development and provide information potentially useful in designing novel therapeutic interventions for this tumor type.

6.
CA Cancer J Clin ; 60(6): 351-75, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20959401

RESUMEN

Inflammatory breast cancer (IBC) is a rare and aggressive form of invasive breast cancer accounting for 2.5% of all breast cancer cases. It is characterized by rapid progression, local and distant metastases, younger age of onset, and lower overall survival compared with other breast cancers. Historically, IBC is a lethal disease with less than a 5% survival rate beyond 5 years when treated with surgery or radiation therapy. Because of its rarity, IBC is often misdiagnosed as mastitis or generalized dermatitis. This review examines IBC's unique clinical presentation, pathology, epidemiology, imaging, and biology and details current multidisciplinary management of the disease, which comprises systemic therapy, surgery, and radiation therapy.


Asunto(s)
Neoplasias Inflamatorias de la Mama/diagnóstico , Neoplasias Inflamatorias de la Mama/terapia , Biomarcadores de Tumor/genética , Índice de Masa Corporal , Quimioterapia Adyuvante , Terapia Combinada/métodos , Diagnóstico Diferencial , Progresión de la Enfermedad , Femenino , Humanos , Incidencia , Neoplasias Inflamatorias de la Mama/epidemiología , Neoplasias Inflamatorias de la Mama/genética , Imagen por Resonancia Magnética , Mamografía , Estadificación de Neoplasias , Obesidad/complicaciones , Tomografía de Emisión de Positrones , Pronóstico , Radioterapia Adyuvante , Enfermedades Raras , Medición de Riesgo , Factores de Riesgo , Tasa de Supervivencia , Tomografía Computarizada por Rayos X , Ultrasonografía Mamaria , Estados Unidos/epidemiología
7.
Proc Natl Acad Sci U S A ; 106(46): 19286-91, 2009 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-19880750

RESUMEN

Profiling the dynamic interaction of p300 with proximal promoters of human T cells identified a class of genes that rapidly coassemble p300 and RNA polymerase II (pol II) following mitogen stimulation. Several of these p300 targets are immediate early genes, including FOS, implicating a prominent role for p300 in the control of primary genetic responses. The recruitment of p300 and pol II rapidly transitions to the assembly of several elongation factors, including the positive transcriptional elongation factor (P-TEFb), the bromodomain-containing protein (BRD4), and the elongin-like eleven nineteen lysine-rich leukemia protein (ELL). However, transcription at many of these rapidly induced genes is transient, wherein swift departure of P-TEFb, BRD4, and ELL coincides with termination of transcriptional elongation. Unexpectedly, both p300 and pol II remain accumulated or "bookmarked" at the proximal promoter long after transcription has terminated, demarking a clear mechanistic separation between the recruitment and elongation phases of transcription in vivo. The bookmarked pol II is depleted of both serine-2 and serine-5 phosphorylation of its C-terminal domain and remains proximally positioned at the promoter for hours. Surprisingly, these p300/pol II bookmarked genes can be readily reactivated, and elongation factors can be reassembled by subsequent addition of nonmitogenic agents that, alone, have minimal effects on transcription in the absence of prior preconditioning by mitogen stimulation. These findings suggest that p300 is likely to play an important role in biological processes in which transcriptional bookmarking or preconditioning influences cellular growth and development through the dynamic priming of genes for response to rechallenge by secondary stimuli.


Asunto(s)
Proteína p300 Asociada a E1A/metabolismo , Regulación de la Expresión Génica , ARN Polimerasa II/metabolismo , Subgrupos de Linfocitos T/metabolismo , Línea Celular , Estudio de Asociación del Genoma Completo , Humanos , Memoria Inmunológica/genética , Mitógenos/farmacología , Regiones Promotoras Genéticas , Subgrupos de Linfocitos T/efectos de los fármacos , Transcripción Genética , Factores de Elongación Transcripcional/metabolismo
8.
Am J Pathol ; 175(6): 2277-87, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19850885

RESUMEN

To delineate the molecular changes that occur in the tumor microenvironment, we previously performed global transcript analysis of human prostate cancer specimens using tissue microdissection and expression microarrays. Epithelial and stromal compartments were individually studied in both tumor and normal fields. Tumor-associated stroma showed a distinctly different expression pattern compared with normal stroma, having 44 differentially expressed transcripts, the majority of which were up-regulated. In the present study, one of the up-regulated transcripts, epithelial cell adhesion activating molecule, was further evaluated at the protein level in 20 prostate cancer cases using immunohistochemistry and a histomathematical analysis strategy. The epithelial cell adhesion activating molecule showed a 76-fold expression increase in the tumor-associated stroma, as compared with matched normal stroma. Moreover, Gleason 4 or 5 tumor stroma was increased 170-fold relative to matched normal stroma, whereas the Gleason 3 tumor area showed only a 36-fold increase, indicating a positive correlation with Gleason tumor grade. Since the stromal compartment may be particularly accessible to vascular-delivered agents, epithelial cell adhesion activating molecule could become a valuable molecular target for imaging or treatment of prostate cancer.


Asunto(s)
Antígenos de Neoplasias/metabolismo , Biomarcadores de Tumor/análisis , Moléculas de Adhesión Celular/metabolismo , Matriz Extracelular/metabolismo , Neoplasias de la Próstata/metabolismo , Molécula de Adhesión Celular Epitelial , Matriz Extracelular/patología , Humanos , Procesamiento de Imagen Asistido por Computador , Inmunohistoquímica , Masculino , Neoplasias de la Próstata/patología
9.
Lab Chip ; 9(7): 917-24, 2009 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-19294302

RESUMEN

We have demonstrated in vitro transcription (IVT) of cDNA sequences from purified Jurkat T-cell mRNA immobilized on microfluidic packed beds down to single-cell quantities. The microfluidically amplified antisense-RNA (aRNA) was nearly identical in length and quantity compared with benchtop reactions using the same starting sample quantities. Microarrays were used to characterize the number and population of genes in each sample, allowing comparison of the microfluidic and benchtop processes. For both benchtop and microfluidic assays, we measured the expression of approximately 4000 to 9000 genes for sample amounts ranging from 20 pg to 10 ng (2 to 1000 cell equivalents), corresponding to 41 to 93% of the absolute number of genes detected from a 100 ng total RNA control sample. Concordance of genes detected between methods (benchtop vs. microfluidic) and repeats (microfluidic vs. microfluidic) typically exceeded 90%. Validation of microarray by Real-time PCR of a panel of five genes suggests transcription of genes present is approximately six times more efficient with the microfluidic IVT compared with benchtop processing. Microfluidic IVT introduces no bias to the gene expression profile of the sample and provides more efficient transcription of mRNA sequences present at the single-cell level.


Asunto(s)
Microfluídica/instrumentación , Microfluídica/métodos , ARN Mensajero/química , ARN/análisis , ADN Complementario/química , ADN Complementario/genética , ARN Polimerasas Dirigidas por ADN , Perfilación de la Expresión Génica/métodos , Humanos , Células Jurkat , Técnicas de Amplificación de Ácido Nucleico/métodos , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , ARN/genética , ARN sin Sentido/análisis , ARN sin Sentido/genética , Reproducibilidad de los Resultados , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Proteínas Virales
10.
Diagn Mol Pathol ; 16(4): 189-97, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18043281

RESUMEN

Characterization of gene expression profiles in tumor cells and the tumor microenvironment is an important step in understanding neoplastic progression. To date, there are limited data available on expression changes that occur in the tumor-associated stroma as either a cause or consequence of cancer. In the present study, we employed a 54,000 target oligonucleotide microarray to compare expression profiles in the 4 major components of the microenvironment: tumor epithelium, tumor-associated stroma, normal epithelium, and normal stroma. Cells from 5 human, whole-mount prostatectomy specimens were microdissected and the extracted and amplified mRNA was hybridized to an Affymetrix Human Genome U133 Plus 2.0 GeneChip. Using the intersection of 2 analysis methods, we identified sets of differentially expressed genes among the 4 components. Forty-four genes were found to be consistently differentially expressed in the tumor-associated stroma; 35 were found in the tumor epithelium. Interestingly, the tumor-associated stroma showed a predominant up-regulation of transcripts compared with normal stroma, in sharp contrast to the overall down-regulation seen in the tumor epithelium relative to normal epithelium. These data provide insight into the molecular changes occurring in tumor-associated stromal cells and suggest new potential targets for future diagnostic, imaging, or therapeutic intervention.


Asunto(s)
Perfilación de la Expresión Génica , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , Epitelio/metabolismo , Humanos , Masculino , Células del Estroma/metabolismo
11.
Cancer Res ; 67(18): 8752-61, 2007 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-17875716

RESUMEN

The biological functions of nuclear topoisomerase I (Top1) have been difficult to study because knocking out TOP1 is lethal in metazoans. To reveal the functions of human Top1, we have generated stable Top1 small interfering RNA (siRNA) cell lines from colon and breast carcinomas (HCT116-siTop1 and MCF-7-siTop1, respectively). In those clones, Top1 is reduced approximately 5-fold and Top2alpha compensates for Top1 deficiency. A prominent feature of the siTop1 cells is genomic instability, with chromosomal aberrations and histone gamma-H2AX foci associated with replication defects. siTop1 cells also show rDNA and nucleolar alterations and increased nuclear volume. Genome-wide transcription profiling revealed 55 genes with consistent changes in siTop1 cells. Among them, asparagine synthetase (ASNS) expression was reduced in siTop1 cells and in cells with transient Top1 down-regulation. Conversely, Top1 complementation increased ASNS, indicating a causal link between Top1 and ASNS expression. Correspondingly, pharmacologic profiling showed L-asparaginase hypersensitivity in the siTop1 cells. Resistance to camptothecin, indenoisoquinoline, aphidicolin, hydroxyurea, and staurosporine and hypersensitivity to etoposide and actinomycin D show that Top1, in addition to being the target of camptothecins, also regulates DNA replication, rDNA stability, and apoptosis. Overall, our studies show the pleiotropic nature of human Top1 activities. In addition to its classic DNA nicking-closing functions, Top1 plays critical nonclassic roles in genomic stability, gene-specific transcription, and response to various anticancer agents. The reported cell lines and approaches described in this article provide new tools to perform detailed functional analyses related to Top1 function.


Asunto(s)
Neoplasias de la Mama/enzimología , Neoplasias del Colon/enzimología , ADN-Topoisomerasas de Tipo I/fisiología , Aspartatoamoníaco Ligasa/biosíntesis , Aspartatoamoníaco Ligasa/genética , Neoplasias de la Mama/genética , Línea Celular Tumoral , Aberraciones Cromosómicas , Neoplasias del Colon/genética , ADN-Topoisomerasas de Tipo I/genética , ADN-Topoisomerasas de Tipo I/metabolismo , Regulación hacia Abajo , Regulación Enzimológica de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Genoma Humano , Inestabilidad Genómica , Células HCT116 , Histonas/biosíntesis , Histonas/genética , Humanos , ARN Mensajero/genética , ARN Interferente Pequeño/genética , Transfección
12.
Bioinformatics ; 23(16): 2088-95, 2007 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-17553856

RESUMEN

MOTIVATION: For Affymetrix microarray platforms, gene expression is determined by computing the difference in signal intensities between perfect match (PM) and mismatch (MM) probesets. Although the use of PM is not controversial, MM probesets have been associated with variance and ultimately inaccurate gene expression calls. A principal focus of this study was to investigate the nature of the MM signal intensities and demonstrate its contribution to the experimental results. RESULTS: While most MM intensities were likely associated with random noise, a subset of approximately 20% (99,485) of the MM probes displayed relatively high signal intensities to the corresponding PM probes (MM > PM) in a non-random fashion; 13,440 of these probes demonstrated exceptionally high 'outlier' intensities. About 15,938 PM probes also demonstrated exceptionally high outlier intensities consistently across all hybridizations. About 92% of the MM > PM probes had either a dThymidine (dT) or a dCytidine (dC) at the 13th position of the probe sequence. MM and PM probes displaying extremely high outlier intensities contained high dC rich nucleotides, and low dA contents at other nucleotides positions along the 25mer probe sequence. Differentially expressed genes generated using Genechip Operating System (GCOS) or modified PM-only methods were also examined. Of those candidate genes identified in the PM-only method, 157 of them were designated by GCOS as absent across all datasets and many others contained probes with MM > PM signal intensities. Our data suggests that MM intensity from PM signal can be a major source of error analysis, leading to fewer potentially biologically important candidate genes. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Asunto(s)
Algoritmos , Disparidad de Par Base/genética , Sondas de ADN/genética , Perfilación de la Expresión Génica/instrumentación , Hibridación Fluorescente in Situ/métodos , Análisis de Secuencia por Matrices de Oligonucleótidos/instrumentación , Análisis de Secuencia de ADN/métodos , Diseño de Equipo , Análisis de Falla de Equipo , Perfilación de la Expresión Génica/métodos , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
13.
Mol Endocrinol ; 21(7): 1552-68, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17440046

RESUMEN

Glucocorticoids, major end effectors of the stress response, play an essential role in the homeostasis of the central nervous system and influence diverse functions of neuronal cells. We found that cyclin-dependent kinase 5 (CDK5), which plays important roles in the morphogenesis and functions of the nervous system and whose aberrant activation is associated with development of neurodegenerative disorders, interacted with the ligand-binding domain of the glucocorticoid receptor (GR) through its activator p35 or its active proteolytic fragment p25. CDK5 phosphorylated GR at multiple serines, including Ser203 and Ser211 of its N-terminal domain, and suppressed the transcriptional activity of this receptor on glucocorticoid-responsive promoters by attenuating attraction of transcriptional cofactors to DNA. In microarray analyses using rat cortical neuronal cells, the CDK5 inhibitor roscovitine differentially regulated the transcriptional activity of the GR on more than 90% of the endogenous glucocorticoid-responsive genes tested. Thus, CDK5 exerts some of its biological activities in neuronal cells through the GR, dynamically modulating GR transcriptional activity in a target promoter-dependent fashion.


Asunto(s)
Quinasa 5 Dependiente de la Ciclina/metabolismo , Receptores de Glucocorticoides/metabolismo , Animales , Secuencia de Bases , Células COS , Línea Celular , Chlorocebus aethiops , Quinasa 5 Dependiente de la Ciclina/química , Quinasa 5 Dependiente de la Ciclina/efectos de los fármacos , Quinasa 5 Dependiente de la Ciclina/genética , Cartilla de ADN/genética , Dexametasona/farmacología , Humanos , Técnicas In Vitro , Ligandos , Complejos Multiproteicos , Proteínas del Tejido Nervioso/química , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Fosforilación , Inhibidores de Proteínas Quinasas/farmacología , Estructura Terciaria de Proteína , Purinas/farmacología , Ratas , Receptores de Glucocorticoides/química , Receptores de Glucocorticoides/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Roscovitina , Serina/química , Estrés Fisiológico/genética , Estrés Fisiológico/metabolismo , Transcripción Genética , Técnicas del Sistema de Dos Híbridos
14.
Int J Cancer ; 120(11): 2353-8, 2007 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-17304513

RESUMEN

Serial analysis of gene expression studies led us to identify a previously unknown gene, c20orf85, that is present in the normal lung epithelium but absent or downregulated in most primary nonsmall cell lung cancers and lung cancer cell lines. We named this gene LLC1 for Low in Lung Cancer 1. LLC1 is located on chromosome 20q13.3 and has a 70% GC content in the promoter region. It has 4 exons and encodes a protein containing 137 amino acids. By in situ hybridization, we observed that LLC1 message is localized in normal lung bronchial epithelial cells but absent in 13 of 14 lung adenocarcinoma and 9 out of 10 lung squamous carcinoma samples. Methylation at CpG sites of the LLC1 promoter was frequently observed in lung cancer cell lines and in a fraction of primary lung cancer tissues. Treatment with 5-aza deoxycytidine resulted in a reduced methylation of the LLC1 promoter concomitant with the increase of LLC1 expression. These results suggest that inactivation of LLC1 by means of promoter methylation is a frequent event in nonsmall cell lung cancer and may play a role in lung tumorigenesis.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/genética , Silenciador del Gen , Neoplasias Pulmonares/genética , Proteínas/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Bovinos , Cartilla de ADN , Perros , Perfilación de la Expresión Génica , Humanos , Ratones , Datos de Secuencia Molecular , Regiones Promotoras Genéticas , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Homología de Secuencia de Aminoácido
15.
Curr Protoc Stem Cell Biol ; Chapter 1: Unit 1B.2, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18785160

RESUMEN

In this unit, starting with purified RNA, experimental protocols for performing microarray expression analysis of embryonic stem cell lines compared to their corresponding differentiated embryocidal bodies are described. Methods for data analysis are suggested, with the goal of determining which genes are differentially expressed between the preparations. As an example, the use of the Affymetrix microarray expression platform is described, but alternative experimental options for analysis of RNA transcript levels are also summarized. This unit suggests quality control metrics, summarizes the critical parameters necessary for obtaining reproducible experimental results, and outlines quantitative PCR methods for validating microarray results.


Asunto(s)
Células Madre Embrionarias/metabolismo , Perfilación de la Expresión Génica/métodos , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Animales , Secuencia de Bases , Cartilla de ADN/genética , Células Madre Embrionarias/citología , Humanos , Ratones , Células Madre Pluripotentes/citología , Células Madre Pluripotentes/metabolismo , ARN/genética , ARN/metabolismo
16.
Stem Cells Dev ; 15(3): 315-23, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16846370

RESUMEN

Recent studies have focused on transcriptional regulation and gene expression profiling of human embryonic stem cells (hESCs). However, little information is available regarding the relationship between RNA expression and transcriptional regulation, which is critical in the complete understanding of pluripotency and differentiation of hESCs. In the current study, we determined RNA expression of three different hESC lines compared to Human universal reference RNA expression (HuU-RNA) using a full genome expression microarray, and compared our results to target genes previously identified using ChIP-on-chip analysis. The objective was to identify genes common between the two methods, and generate a more reliable list of embryonic signature genes. Even though hESCs were obtained from different sources and maintained under different conditions, a considerable number of genes could be identified as common between RNA expression and transcriptional regulation analyses. As an example, results from ChIP-on-chip studies show that OCT4, SOX2, and NANOG co-occupy SOX2, OCT4, TDGF1, GJA1, SET, and DPPA4 genes. The results are consistent with RNA expression analyses that demonstrate these genes as differently expressed in our hESC lines, further substantiating their role across cell types and confirming their importance as embryonic signatures. In addition, we report the differential expression of growth arrest-specific (GAS) family of genes in hESC. GAS2L1 and GAS3 members of this family appear to be transcriptionally regulated by OCT4, SOX2, or NANOG, whereas GAS5 and GAS6 are not; all of the genes are differentially expressed, as determined by microarray and validated via quantitative (Q)- PCR. Collectively, these data provide insight into the relationship between gene expression and transcriptional regulation, resulting in a reliable list of genes associated with hESCs.


Asunto(s)
Embrión de Mamíferos/citología , Regulación del Desarrollo de la Expresión Génica/genética , Células Madre/metabolismo , Transcripción Genética/genética , Proteínas de Unión al ADN/genética , Perfilación de la Expresión Génica , Genes del Desarrollo/genética , Proteínas HMGB/genética , Proteínas de Homeodominio/genética , Humanos , Análisis por Micromatrices , Proteína Homeótica Nanog , Factor 3 de Transcripción de Unión a Octámeros/genética , ARN/genética , ARN/metabolismo , Reproducibilidad de los Resultados , Factores de Transcripción SOXB1 , Factores de Transcripción/genética
17.
Nanomedicine ; 1(2): 101-9, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17292064

RESUMEN

Cancer is the leading cause of death in the United States among people younger than 85 years, and for the first time has surpassed heart disease as the number one killer. This worrisome statistic has resulted not from an increase in the incidence of cancer, but because deaths from heart disease have dropped nearly in half while the number of cancer-related deaths has remained about the same. This fact accentuates the need for a new generation of more effective therapies for cancer. In this review, the development of new therapies will be discussed in the context of advances in nanotechnologies related to cancer detection, analysis, diagnosis, and therapeutic intervention. First, several nanoanalytical methods, such as the use of quantum dots in detection and imaging of cancer, will be described. These techniques will be essential to the process of precisely describing cancer at the level of the cell and whole organism. Second, examples of how nanotechnologies can be used in the development of new therapies will be given, including methods that might allow for more efficient and accurate drug delivery and rationally designed, targeted drugs. Finally, a new initiative--the National Cancer Institute Alliance for Nanotechnology in Cancer--will be described and discussed with respect to the scientific issues, policies, and funding.


Asunto(s)
Antineoplásicos/administración & dosificación , Diagnóstico por Imagen/tendencias , Sistemas de Liberación de Medicamentos/tendencias , Quimioterapia/tendencias , Nanomedicina/tendencias , Neoplasias/diagnóstico , Neoplasias/terapia , Terapia Genética/tendencias , Humanos , Robótica/tendencias
18.
Expert Rev Mol Diagn ; 4(6): 831-40, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15525225

RESUMEN

Most expression profiling studies of solid tumors have used biopsy samples containing large numbers of contaminating stromal and other cell types, thereby complicating any precise delineation of gene expression in nontumor versus tumor cell types. Combining laser capture microdissection, RNA amplification protocols, microarray technologies and our knowledge of the human genome sequence, it is possible to isolate pure populations of cells or even a single cell and interrogate the expression of thousands of sequences for the purpose of more precisely defining the biology of the tumor cell. Although many of the studies that currently allow for characterization of small sample preparations and single cells were performed utilizing noncancer cell types, and in some cases isolation protocols other than laser capture microdissection, a list of protocols are described that could be used for the expression analysis of individual tumor cells. Application of these experimental approaches to cancer studies may permit a more accurate definition of the biology of the cancer cell, so that ultimately, more specific targeted therapies can be developed.


Asunto(s)
Perfilación de la Expresión Génica , Rayos Láser , Microdisección/métodos , Neoplasias/genética , Análisis de Secuencia por Matrices de Oligonucleótidos , Linfocitos B/metabolismo , Humanos , Neoplasias/diagnóstico , Neoplasias/metabolismo , Neuronas/metabolismo , Linfocitos T/metabolismo
19.
Mol Cancer Res ; 2(9): 489-94, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15383627

RESUMEN

HIN-1 (high in normal-1) is a candidate tumor suppressor identified as a gene silenced by methylation in the majority of breast carcinomas. HIN-1 is highly expressed in the mammary gland, trachea, lung, prostate, pancreas, and salivary gland, and in the lung, its expression is primarily restricted to bronchial epithelial cells. In this report, we show that, correlating with the secretory nature of HIN-1, high levels of HIN-1 protein are detected in bronchial lavage, saliva, plasma, and serum. To determine if, similar to breast carcinomas, HIN-1 is also silenced in tumors originating from other organs with high HIN-1 expression, we analyzed its expression and promoter methylation status in lung, prostate, and pancreatic carcinomas. Nearly all prostate and a significant fraction of lung and pancreatic carcinomas showed HIN-1 hypermethylation, and the majority of lung and prostate tumors lacked HIN-1 expression. In lung carcinomas, the degree of HIN-1 methylation differed among tumor subtypes (P = 0.02), with the highest level of HIN-1 methylation observed in squamous cell carcinomas and the lowest in small cell lung cancer. In lung adenocarcinomas, the expression of HIN-1 correlated with cellular differentiation status. Hypermethylation of the HIN-1 promoter was also frequently observed in normal tissue adjacent to tumors but not in normal tissue from noncancer patients, implying that HIN-1 promoter methylation may be a marker of premalignant changes. Thus, silencing of HIN-1 expression and methylation of its promoter occurs in multiple human cancer types, suggesting that elimination of HIN-1 function may contribute to several forms of epithelial tumorigenesis.


Asunto(s)
Citocinas/genética , Metilación de ADN , Regulación Neoplásica de la Expresión Génica , Neoplasias/clasificación , Neoplasias/genética , Regiones Promotoras Genéticas/genética , Proteínas Supresoras de Tumor/genética , Líquidos Corporales/metabolismo , Línea Celular Tumoral , Citocinas/metabolismo , Humanos , Pulmón/metabolismo , Pulmón/patología , Neoplasias Pulmonares/genética , Masculino , Neoplasias/patología , Páncreas/metabolismo , Neoplasias Pancreáticas/genética , Próstata/metabolismo , Neoplasias de la Próstata/genética , Proteínas Supresoras de Tumor/metabolismo
20.
Clin Cancer Res ; 10(13): 4314-24, 2004 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-15240517

RESUMEN

We immunohistochemically examined 12 core proteins involved in the chromatin remodeling machinery using a tissue microarray composed of 150 lung adenocarcinoma (AD) and 150 squamous cell carcinoma (SCC) cases. Most of the proteins showed nuclear staining, whereas some also showed cytoplasmic or membranous staining. When the expression patterns of all tested antigens were considered, proteins with nuclear staining clustered into two major groups. Nuclear signals of BRM, Ini-1, retinoblastoma, mSin3A, HDAC1, and HAT1 clustered together, whereas nuclear signals of BRG1, BAF155, HDAC2, BAF170, and RbAP48 formed a second cluster. Additionally, two thirds of the cases on the lung tissue array had follow-up information, and survival analysis was performed for each of the tested proteins. Positive nuclear BRM (N-BRM) staining correlated with a favorable prognosis in SCC and AD patients with a 5 year-survival of 53.5% compared with 32.3% for those whose tumors were negative for N-BRM (P = 0.015). Furthermore, patients whose tumors stained positive for both N-BRM and nuclear BRG1 had a 5 year-survival of 72% compared with 33.6% (P = 0.013) for those whose tumors were positive for either or negative for both markers. In contrast, membranous BRM (M-BRM) staining correlated with a poorer prognosis in AD patients with a 5 year-survival of 16.7% compared with those without M-BRM staining (38.1%; P = 0.016). These results support the notion that BRM and BRG1 participate in two distinct chromosome remodeling complexes that are functionally complementary and that the nuclear presence of BRM, its coexpression with nuclear BRG1, and the altered cellular localization of BRM (M-BRM) are useful markers for non-small cell lung cancer prognosis.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/diagnóstico , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Proteínas de Ciclo Celular/metabolismo , Cromatina/metabolismo , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/metabolismo , Proteínas Nucleares/metabolismo , Transactivadores/metabolismo , Factores de Transcripción/metabolismo , Adenocarcinoma/diagnóstico , Adenocarcinoma/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Especificidad de Anticuerpos , Western Blotting , Carcinoma de Células Escamosas , Núcleo Celular/metabolismo , Cromosomas/ultraestructura , Estudios de Cohortes , Citoplasma/metabolismo , ADN Helicasas , Proteínas de Drosophila , Femenino , Humanos , Inmunohistoquímica , Pulmón/patología , Masculino , Persona de Mediana Edad , Análisis de Secuencia por Matrices de Oligonucleótidos , Pronóstico , Control de Calidad , Proteína de Retinoblastoma/metabolismo , Factores de Tiempo
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