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1.
Breast Cancer Res ; 16(3): R67, 2014 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-24962108

RESUMO

INTRODUCTION: Breast cancer is a devastating disease that results in approximately 40,000 deaths each year in the USA. Current drug screening and chemopreventatitive methods are suboptimal, due in part to the poor specificity of compounds for cancer cells. Poly (ADP-ribose) polymerase 1 (PARP1) inhibitor (PARPi)-mediated therapy is a promising approach for familial breast cancers caused by mutations of breast cancer-associated gene-1 and -2 (BRCA1/2), yet drug resistance frequently occurs during the treatment. Moreover, PARPis exhibit very little effect on cancers that are proficient for DNA repair and clinical efficacy for PARPis as single-agent therapies has yet to be illustrated. METHODS: Using a quantitative high-throughput screening approach, we screened a library containing 2,816 drugs, most of which are approved for human or animal use by the Food and Drug Administration (FDA) or other countries, to identify compounds that sensitize breast cancer cells to PARPi. After initial screening, we performed further cellular and molecular analysis on lestaurtinib, which is an orally bioavailable multikinase inhibitor and has been used in clinical trials for myeloproliferative disorders and acute myelogenous leukemia. RESULTS: Our study indicated that lestaurtinib is highly potent against breast cancers as a mono-treatment agent. It also strongly enhanced the activity of the potent PARPi AG14361 on breast cancer cell growth both in vitro and in vivo conditions. The inhibition of cancer growth is measured by increased apoptosis and reduced cell proliferation. Consistent with this, the treatment results in activation of caspase 3/7, and accumulation of cells in the G2 phase of the cell cycle, irrespective of their BRCA1 status. Finally, we demonstrated that AG14361 inhibits NF-κB signaling, which is further enhanced by lestaurtinib treatment. CONCLUSIONS: Lestaurtinib amplifies the ability of the PARP1 inhibitor AG14361 to kill BRCA1 mutant and wild-type breast cancer cells, at least in part, by inhibiting NF-κB signaling. Each of these drugs has been approved for clinical trials for several different cancers, thus, their combination treatment should be applicable for a breast cancer trial in the future.


Assuntos
Proteína BRCA1/genética , Benzodiazepinas/farmacologia , Neoplasias da Mama/tratamento farmacológico , Carbazóis/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Azulenos/farmacologia , Neoplasias da Mama/genética , Caspase 3/metabolismo , Caspase 7/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Reposicionamento de Medicamentos , Resistencia a Medicamentos Antineoplásicos , Sinergismo Farmacológico , Feminino , Furanos , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Ensaios de Triagem em Larga Escala , Humanos , Camundongos , Camundongos Nus , NF-kappa B/antagonistas & inibidores , Transplante de Neoplasias , Poli(ADP-Ribose) Polimerase-1 , Interferência de RNA , RNA Interferente Pequeno
2.
J Exp Ther Oncol ; 7(1): 65-72, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18472643

RESUMO

Cervical cancer is one of the first causes of death in Mexican women population. The plasma proteome has a wide dynamic range concentrations of different protein and their alterations reflect the physiological state of the individual's health. The aim of this study was to characterize the 2D-PAGE serum patterns from healthy women and with different levels of cervical lesions. Changes in haptoglobin, apolipoproteins, and transthyretin, when comparing the serum from healthy women and serum from patients with different levels of cervical lesion were found. The Western blot analysis showed increasing concentrations of metalloproteinases (MMP's), proteins with important biological roles in tumor development and metastasis. Protein profiles in conjunction with MS, bioinformatics, and Western blot analysis, allow us to compile information for the acquisition of results to proposed candidates biomarkers of cervical cancer among Mexican women population.


Assuntos
Biomarcadores Tumorais/sangue , Neoplasias do Colo do Útero/sangue , Apolipoproteínas/sangue , Western Blotting , Estudos de Casos e Controles , Eletroforese em Gel Bidimensional , Feminino , Haptoglobinas/metabolismo , Humanos , Metaloproteases/sangue , Invasividade Neoplásica , Pré-Albumina/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Neoplasias do Colo do Útero/patologia , Displasia do Colo do Útero/sangue , Displasia do Colo do Útero/patologia
3.
Rev Invest Clin ; 58(4): 335-49, 2006.
Artigo em Espanhol | MEDLINE | ID: mdl-17146945

RESUMO

Double-stranded RNA (dsRNA) induces a sequence-specific silencing in eukaryotic cells. This silencing process beggins when long dsRNA is cleaved to 21 to 26 long small RNA by means of the RNAse III-type enzyme Dicer. These small dsRNA are included into silencing effector complexes, that are targeted to complementary sequences. Small RNA dependent gene silencing can be achieved by distinct mechanisms based depending mainly on the nature of target sequences and on the proteins present in the effector complex. The route of interference RNA (RNAi) begins when Dicer yields small interference RNA (siRNA) that bind to complementary mRNA for its degradation, forming the RISC complex. siRNA are naturally formed from transposons and dsRNA viruses during its replication, as well as from other bidirectional transcribed repetitive sequences. Some of the enzymes thar are part of the RNAi machinery, including Dicer, are encoded by multigene families in many species, that also play a role in other mechanisms of RND-dependent gene silencing. MicroRNA's (miRNA) are other small RNA's that can induce gene silencing at the mRNA level. These are formed in a general manner when Dicer process hairpin structures resulting from the transcription of non-coding sequences from plant and animal genomes. miRNA's are integrated into a RISC-like complex, after which, depending on their degree of complementarity with target mRNA, can either repress translation or induce mRNA degradation. miRNA-dependent silencing is essential for the development of multicellular organisms. Artificial RNAi induction by means of siRNA or miRNA is being used as a tool to inactivate gene expression in culture cells and in living organisms. This review focuses on the progress in the understanding of the mechanisms involved in gene regulation by RNA in animals and details some current efforts to apply theses phenomena as a tool in research and in the therapeutic of human diseases.


Assuntos
MicroRNAs/metabolismo , Interferência de RNA/fisiologia , RNA Interferente Pequeno/metabolismo , Humanos , MicroRNAs/genética , RNA Interferente Pequeno/genética
4.
Oncotarget ; 7(51): 84439-84452, 2016 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-27806319

RESUMO

Cisplatin is an effective breast cancer drug but resistance often develops over prolonged chemotherapy. Therefore, we performed a candidate approach RNAi screen in combination with cisplatin treatment to identify molecular pathways conferring survival advantages. The screen identified ATP7A as a therapeutic target. ATP7A is a copper ATPase transporter responsible for intercellular movement and sequestering of cisplatin. Pharmaceutical replacement for ATP7A by ammonium tetrathiomolybdate (TM) enhanced cisplatin treatment in breast cancer cells. Allograft and xenograft models in athymic nude mice treated with cisplatin/TM exhibited retarded tumor growth, reduced accumulation of cancer stem cells and decreased cell proliferation as compared to mono-treatment with cisplatin or TM. Cisplatin/TM treatment of cisplatin-resistant tumors reduced ATP7A protein levels, attenuated cisplatin sequestering by ATP7A, increased nuclear availability of cisplatin, and subsequently enhanced DNA damage and apoptosis. Microarray analysis of gene ontology pathways that responded uniquely to cisplatin/TM double treatment depicted changes in cell cycle regulation, specifically in the G1/S transition. These findings offer the potential to combat platinum-resistant tumors and sensitize patients to conventional breast cancer treatment by identifying and targeting the resistant tumors' unique molecular adaptations.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias da Mama/tratamento farmacológico , Cisplatino/farmacologia , ATPases Transportadoras de Cobre/antagonistas & inibidores , Molibdênio/farmacologia , Inibidores da Angiogênese/administração & dosagem , Inibidores da Angiogênese/farmacologia , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Cisplatino/administração & dosagem , ATPases Transportadoras de Cobre/genética , ATPases Transportadoras de Cobre/metabolismo , Sinergismo Farmacológico , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Células MCF-7 , Camundongos Nus , Molibdênio/administração & dosagem , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Interferência de RNA , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
5.
BMC Genomics ; 6: 130, 2005 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-16171524

RESUMO

BACKGROUND: Serial Analysis of Gene Expression (SAGE) is a new technique that allows a detailed and profound quantitative and qualitative knowledge of gene expression profile, without previous knowledge of sequence of analyzed genes. We carried out a modification of SAGE methodology (microSAGE), useful for the analysis of limited quantities of tissue samples, on normal human cervical tissue obtained from a donor without histopathological lesions. Cervical epithelium is constituted mainly by cervical keratinocytes which are the targets of human papilloma virus (HPV), where persistent HPV infection of cervical epithelium is associated with an increase risk for developing cervical carcinomas (CC). RESULTS: We report here a transcriptome analysis of cervical tissue by SAGE, derived from 30,418 sequenced tags that provide a wealth of information about the gene products involved in normal cervical epithelium physiology, as well as genes not previously found in uterine cervix tissue involved in the process of epidermal differentiation. CONCLUSION: This first comprehensive and profound analysis of uterine cervix transcriptome, should be useful for the identification of genes involved in normal cervix uterine function, and candidate genes associated with cervical carcinoma.


Assuntos
Colo do Útero/metabolismo , Epitélio/metabolismo , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Regulação da Expressão Gênica , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Etiquetas de Sequências Expressas , Feminino , Fibroblastos/metabolismo , Expressão Gênica , Biblioteca Gênica , Humanos , Modelos Estatísticos , Papillomaviridae/metabolismo , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Distribuição Tecidual , Transcrição Gênica
6.
BMC Cancer ; 5: 68, 2005 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-15989693

RESUMO

BACKGROUND: Cervical carcinoma (CC) is one of the most common cancers among women worldwide and the first cause of death among the Mexican female population. CC progression shows a continuum of neoplastic transitions until invasion. Matrix metalloproteinases (MMPs) and cathepsins play a central role on the enhancement of tumor-induced angiogenesis, cell migration, proliferation, apoptosis and connective tissue degradation. MMPs -2 and -9 expression has been widely studied in cervical cancer. Nevertheless, no other metalloproteinases or cathepsins have been yet related with the progression and/or invasion of this type of cancer. METHODS: Three HPV18 CC cell lines, two HPV16 CC cell lines and three HPV16 tumor CC tissues were compared with three morphologically normal, HPV negative, cervical specimens by cDNA arrays. Overexpression of selected genes was confirmed by end point semiquantitative reverse transcription-PCR with densitometry. In situ hybridization and protein expression of selected genes was further studied by means of two tissue microarrays, one consisting of 10 HSIL and 15 CC and the other one of 15 normal cervical and 10 LSIL tissues. RESULTS: TIMP1, Integrins alpha 1 and 4, cadherin 2 and 11, Cathepsins F, B L2, MMP 9, 10 11 and 12 were upregulated and Cathepsin S, L, H and C, Cadherins 3 and 4, TIMP3, MMP 13, Elastase 2 and Integrin beta 8 were found to be downregulated by cDNA arrays. Endpoint RT-PCR with densitometry gave consistent results with the cDNA array findings for all three genes selected for study (CTSF, MMP11 and MMP12). In situ hybridization of all three genes confirmed overexpression in all the HSIL and CC. Two of the selected proteins were detected in LSIL, HSIL and CC by immunohistochemistry. CONCLUSION: Novel undetected CC promoting genes have been identified. Increased transcription of these genes may result in overexpression of proteins, such as CTSF, MMP11 and MMP12 which could contribute to the pathogenesis of CC.


Assuntos
Carcinoma/metabolismo , Catepsinas/biossíntese , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Metaloendopeptidases/biossíntese , Neoplasias do Colo do Útero/enzimologia , Catepsina F , DNA Complementar/metabolismo , Progressão da Doença , Feminino , Células HeLa , Humanos , Imuno-Histoquímica , Hibridização In Situ , Metaloproteinase 11 da Matriz , Metaloproteinase 12 da Matriz , Hibridização de Ácido Nucleico , Análise de Sequência com Séries de Oligonucleotídeos , Sondas de Oligonucleotídeos/química , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transcrição Gênica
7.
BMC Cancer ; 5: 77, 2005 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-16004614

RESUMO

BACKGROUND: Chromosomal Comparative Genomic Hybridization (CGH) has been applied to all stages of cervical carcinoma progression, defining a specific pattern of chromosomal imbalances in this tumor. However, given its limited spatial resolution, chromosomal CGH has offered only general information regarding the possible genetic targets of DNA copy number changes. METHODS: In order to further define specific DNA copy number changes in cervical cancer, we analyzed 20 cervical samples (3 pre-malignant lesions, 10 invasive tumors, and 7 cell lines), using the GenoSensor microarray CGH system to define particular genetic targets that suffer copy number changes. RESULTS: The most common DNA gains detected by array CGH in the invasive samples were located at the RBP1-RBP2 (3q21-q22) genes, the sub-telomeric clone C84C11/T3 (5ptel), D5S23 (5p15.2) and the DAB2 gene (5p13) in 58.8% of the samples. The most common losses were found at the FHIT gene (3p14.2) in 47% of the samples, followed by deletions at D8S504 (8p23.3), CTDP1-SHGC- 145820 (18qtel), KIT (4q11-q12), D1S427-FAF1 (1p32.3), D9S325 (9qtel), EIF4E (eukaryotic translation initiation factor 4E, 4q24), RB1 (13q14), and DXS7132 (Xq12) present in 5/17 (29.4%) of the samples. CONCLUSION: Our results confirm the presence of a specific pattern of chromosomal imbalances in cervical carcinoma and define specific targets that are suffering DNA copy number changes in this neoplasm.


Assuntos
Aberrações Cromossômicas , Deleção Cromossômica , DNA de Neoplasias , Regulação Neoplásica da Expressão Gênica , Hibridização de Ácido Nucleico , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Neoplasias do Colo do Útero/genética , Linhagem Celular Tumoral , DNA/genética , Primers do DNA/química , Feminino , Células HeLa , Humanos , Processamento de Imagem Assistida por Computador , Perda de Heterozigosidade , Papillomaviridae/genética , Reação em Cadeia da Polimerase , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/metabolismo
8.
Arch Med Res ; 36(5): 448-58, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16099320

RESUMO

BACKGROUND: One of the most frequent malignancies in women worldwide is carcinoma of the uterine cervix. High-risk human papillomavirus (HPV) infection is considered the most important etiological factor of uterine cervical cancer. Our aim was to identify novel cellular genes that could potentially act as predictive molecular markers for human cervical cancer by means of cDNA arrays. METHODS: We used cDNA arrays to examine the expression profiles of six cell lines derived from human cervical cancer, three HPV+ tumor samples and three normal (HPV-) epithelium tissues. Data normalization was performed and the top overexpressed genes were obtained. Hierarchical cluster was performed and, to validate some of the differentially expressed genes between normal and carcinogenic samples, semi-quantitative RT-PCR, in situ hybridization and immunohistochemistry were performed in tissue samples. RESULTS: Four genes were demonstrated to be consistently overexpressed in invasive cervical cancer biopsies; three novel genes not previously related to cervical cancer: MMP10, Lamc2 and Claudin 1. Moreover, overexpression of IL6 and VEGF was corroborated. CONCLUSIONS: The identification of characteristic molecular changes in cervical cells by carcinogenesis and HPV infection can lead to a better understanding of cervical cancer. cDNA arrays are beginning to provide new possible molecular markers for prognosis and diagnosis. This technology could eventually help to elucidate the biological differences of the particular mechanisms associated with each different HPV-type infection and those with a poor prognosis.


Assuntos
Análise de Sequência com Séries de Oligonucleotídeos , Papillomaviridae/genética , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/virologia , Linhagem Celular Tumoral , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Hibridização In Situ , Infecções por Papillomavirus/complicações , Distribuição Aleatória , Neoplasias do Colo do Útero/etiologia , Neoplasias do Colo do Útero/patologia
9.
Rev Invest Clin ; 57(3): 434-41, 2005.
Artigo em Espanhol | MEDLINE | ID: mdl-16187704

RESUMO

High risk human papillomavirus (HPV) infection is considered to be the most important etiological factor of Cervical Uterine Cancer. In order to determine the global expression pattern and to identify possible molecular markers of cervical cancer, cDNA arrays with probe sets complementary to 8,000 human genes were used to examine the expression profiles among 5 cell lines derived from human cervical cancer, three HPV16(+) tumor samples and three normal cervical tissues HPV(-). The levels of expression of different cellular processes were identified. Hierarchical clustering was performed and the gene expression using RT-PCR was confirmed. Two genes were found to be consistently overexpressed in invasive cervical cancer biopsies; one of them, IL-6 was previously reported to be overexpressed in cervical cancer and one novel gene, MMP10, previously not known to be related to cervical cancer. Hierarchical clustering of the expression data revealed that samples with common HPV type infection grouped together, maybe this could mean that differences between HPV types could be indirectly determined by expression profiles.


Assuntos
Biomarcadores Tumorais/genética , Carcinoma de Células Escamosas/genética , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Proteínas de Neoplasias/genética , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/genética , Neoplasias do Colo do Útero/genética , Adulto , Biomarcadores Tumorais/biossíntese , Biópsia , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/virologia , Linhagem Celular Tumoral/metabolismo , Linhagem Celular Tumoral/virologia , Colo do Útero/patologia , Colposcopia , DNA Complementar/genética , DNA de Neoplasias/genética , DNA de Neoplasias/isolamento & purificação , Feminino , Humanos , Interleucina-6/biossíntese , Interleucina-6/genética , Metaloproteinase 10 da Matriz , Metaloendopeptidases/biossíntese , Metaloendopeptidases/genética , Proteínas de Neoplasias/biossíntese , Infecções por Papillomavirus/metabolismo , Infecções por Papillomavirus/patologia , Infecções por Papillomavirus/virologia , Pré-Menopausa , RNA Mensageiro/genética , RNA Mensageiro/isolamento & purificação , RNA Neoplásico/genética , RNA Neoplásico/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/virologia
10.
J Ovarian Res ; 6(1): 61, 2013 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-24007497

RESUMO

BACKGROUND: Studies of alternative mRNA splicing (AS) in health and disease have yet to yield the complete picture of protein diversity and its role in physiology and pathology. Some forms of cancer appear to be associated to certain alternative mRNA splice variants, but their role in the cancer development and outcome is unclear. METHODS: We examined AS profiles by means of whole genome exon expression microarrays (Affymetrix GeneChip 1.0) in ovarian tumors and ovarian cancer-derived cell lines, compared to healthy ovarian tissue. Alternatively spliced genes expressed predominantly in ovarian tumors and cell lines were confirmed by RT-PCR. RESULTS: Among several significantly overexpressed AS genes in malignant ovarian tumors and ovarian cancer cell lines, the most significant one was that of the zinc finger protein ZNF695, with two previously unknown mRNA splice variants identified in ovarian tumors and cell lines. The identity of ZNF695 AS variants was confirmed by cloning and sequencing of the amplicons obtained from ovarian cancer tissue and cell lines. CONCLUSIONS: Alternative ZNF695 mRNA splicing could be a marker of ovarian cancer with possible implications on its pathogenesis.

11.
Med Oncol ; 28(4): 1507-13, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20661667

RESUMO

Cervical cancer (CC) is the second most common cancer in Mexican women. Human papillomavirus (HPV) infection is necessary but not sufficient for CC development. Furthermore, genetic factors as polymorphisms could be important susceptibility factors. Controversial results regarding TP53 polymorphisms specifically in codon 72 of CC have been reported. In the present work, the exon 4 sequence of TP53 gene in CC and healthy Mexican-mestizo women were analyzed. A group of 111 women with CC and 126 healthy women (control) were included. Peripheral blood cells for polymorphism analysis and cervical scrape for HPV detection were used. PCR of exon 4 of TP53 were subjected to denaturing high-performance liquid chromatography (DHPLC) analysis and sequencing. HPV detection was subjected to PCR and sequencing. The statistical analysis was carried out using the Arlequin software. Codon 72 Arg/Arg was the most common SNP detected, and Hardy-Weinberg analysis showed equilibrium in control and CC samples (P>0.05). Wild type sequence of TP53 exon 4 was detected in 66 and 57% in control and CC samples, respectively. For codon 72 Arg/Arg, differences between control and CC women were found (P=0.043). An association between HPV 16/18 infection and 72 Arg/Arg in woman with CC was found (P=0.026). Haplotype GC (codon 36 and 72) was statistically significantly associated with CC (P=0.011). HPV 16 was the most common viral type. Codon 72 Arg/Arg is the most common polymorphism in the Mexican population and could be associated to HPV 16 and/or HPV 18 infection in CC.


Assuntos
Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/genética , Polimorfismo de Nucleotídeo Único , Proteína Supressora de Tumor p53/genética , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/virologia , Adulto , Sequência de Bases , Cromatografia Líquida de Alta Pressão , Éxons/genética , Feminino , Predisposição Genética para Doença , Genótipo , Haplótipos , Papillomavirus Humano 16 , Papillomavirus Humano 18 , Humanos , México , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Reação em Cadeia da Polimerase , Neoplasias do Colo do Útero/patologia
12.
Cell Metab ; 12(3): 224-36, 2010 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-20816089

RESUMO

Under various conditions, mammals have the ability to maintain serum glucose concentration within a narrow range. SIRT1 plays an important role in regulating gluconeogenesis and fat metabolism; however, the underlying mechanisms remain elusive. Here, we show that SIRT1 forms a complex with FOXO3a and NRF1 on the SIRT6 promoter and positively regulates expression of SIRT6, which, in turn, negatively regulates glycolysis, triglyceride synthesis, and fat metabolism by deacetylating histone H3 lysine 9 in the promoter of many genes involved in these processes. Liver-specific deletion of SIRT6 in mice causes profound alterations in gene expression, leading to increased glycolysis, triglyceride synthesis, reduced beta oxidation, and fatty liver formation. Human fatty liver samples exhibited significantly lower levels of SIRT6 than did normal controls. Thus, SIRT6 plays a critical role in fat metabolism and may serve as a therapeutic target for treating fatty liver disease, the most common cause of liver dysfunction in humans.


Assuntos
Fígado Gorduroso/metabolismo , Glicólise/fisiologia , Fígado/patologia , Fígado/fisiologia , Sirtuínas/metabolismo , Triglicerídeos/biossíntese , Adolescente , Adulto , Animais , Sítios de Ligação , Linhagem Celular , Feminino , Proteína Forkhead Box O3 , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Deleção de Genes , Regulação da Expressão Gênica , Histonas/metabolismo , Humanos , Metabolismo dos Lipídeos , Fígado/citologia , Hepatopatias/genética , Hepatopatias/metabolismo , Masculino , Camundongos , Pessoa de Meia-Idade , Fator 1 Nuclear Respiratório/genética , Fator 1 Nuclear Respiratório/metabolismo , Regiões Promotoras Genéticas , Sirtuína 1/genética , Sirtuína 1/metabolismo , Sirtuínas/genética
13.
Reumatol Clin ; 4(1): 19-31, 2008 Jan.
Artigo em Espanhol | MEDLINE | ID: mdl-21794490

RESUMO

Rheumatoid arthritis (RA) is a chronic, disabbling disease that affects individuals during the productive years of their lives. Modern treatment for RA includes the so called "biologic" therapy, which is based on recombinant proteins that modify the biologic processes. These agents have potent therapeutic effects and different mechanisms of action. Nevertheless, therapeutic failure still prevails. Treatment that prevents disability in RA must be started in an early manner, before the development of complications and, ideally, with a minimum possibility of therapeutic failure. As yet, there are no clinical or laboratory criteria to identify those patients with a higher probability of responding to particular types of therapy, delaying control of RA ad affecting the prevention of incapacity. Research into gene diversity through single-nucleotide polymorphisms (SNPs) by means of microarray systems, allows the detailed analysis of gene factors associated to a given disease. SNPs have been recently applied to the study of RA, where the major polymorphisms associated to RA occur primarily in genes that code for proteins related to the initiation of an immune response and/or the control of cellular activity in the immune system, in addition to genes related to tissue repair. The specific meaning of these findings is in its initial stages of research. On the other hand, proteomics relate to the analysis of protein expression profiles at multiple levels. Both types of studies will contribute to the knowledge of patterns of gene expression in RA compared to the general population, and will allow an understanding of the pathogenesis of RA. Moreover, proteomic and genomic profiles can be employed to designs probes that identify individuals with the risk of developing RA, individually predict the response to different therapeutic modalities (pharmacogenomics) and for the follow-up of the biologic response to therapy.

14.
Infect Agent Cancer ; 2: 16, 2007 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-17822553

RESUMO

BACKGROUND: Cervical carcinoma (CC) is a leading cause of death among women worldwide. Human papilloma virus (HPV) is a major etiological factor in CC and HPV 16 is the more frequent viral type present. Our aim was to characterize metabolic pathways altered in HPV 16 tumor samples by means of transcriptome wide analysis and bioinformatics tools for visualizing expression data in the context of KEGG biological pathways. RESULTS: We found 2,067 genes significantly up or down-modulated (at least 2-fold) in tumor clinical samples compared to normal tissues, representing ~3.7% of analyzed genes. Cervical carcinoma was associated with an important up-regulation of Wnt signaling pathway, which was validated by in situ hybridization in clinical samples. Other up-regulated pathways were those of calcium signaling and MAPK signaling, as well as cell cycle-related genes. There was down-regulation of focal adhesion, TGF-beta signaling, among other metabolic pathways. CONCLUSION: This analysis of HPV 16 tumors transcriptome could be useful for the identification of genes and molecular pathways involved in the pathogenesis of cervical carcinoma. Understanding the possible role of these proteins in the pathogenesis of CC deserves further studies.

15.
Rev. invest. clín ; Rev. invest. clín;58(4): 335-349, jul.-ago. 2006. ilus
Artigo em Espanhol | LILACS | ID: lil-632381

RESUMO

Double-stranded RNA (dsRNA) induces a sequence-specific silencing in eukaryotic cells. This silencing process beggins when long dsRNA is cleaved to 21 to 26 long small RNA by means of the RNAse III-type enzyme Dicer. These small dsRNA are included into silencing effector complexes, that are targeted to complementary sequences. Small RNA dependent gene silencing can be achieved by distinct mechanisms based depending mainly on the nature of target sequences and on the proteins present in the effector complex. The route of interference RNA (RNAi) begins when Dicer yields small interference RNA (siR-NA) that bind to complementary mRNA for its degradation, forming the RISC complex. siRNA are naturally formed from transposons and dsRNA viruses during its replication, as well as from other bidirectional transcribed repetitive sequences. Some of the enzymes thar are part of the RNAi machinery, including Dicer, are encoded by multigene families in many species, that also play a role in other mechanisms of RND-dependent gene silencing. MicroRNA's (miRNA) are other small RNA's that can induce gene silencing at the mRNA level. These are formed in a general manner when Dicer process hairpin structures resulting from the transcription of non-coding sequences from plant and animal genomes. miRNA's are integrated into a RISC-like complex, after which, depending on their degree of complementarity with target mRNA, can either repress translation or induce mRNA degradation. miRNA-dependent silencing is essential for the development of multicellular organisms. Artificial RNAi induction by means of siRNA or miRNA is being used as a tool to inactivate gene expression in culture cells and in living organisms. This review focuses on the progress in the understanding of the mechanisms involved in gene regulation by RNA in animals and details some current efforts to apply theses phenomena as a tool in research and in the therapeutic of human diseases.


El RNA de doble cadena puede inducir un silenciamiento secuencia-específico en eucarionte. Este proceso de silenciamiento se inicia cuando el RNAdc largo es procesado a RNA pequeño de 21 a 26 nucleótidos mediante la enzima RNAsa III Dicer. Estos RNA pequeños se incorporan a complejos efectores de silenciamiento, que son guiados a secuencias complementarias blanco. Existen diferentes tipos de silenciamiento, cuyas diferencias se basan principalmente en la naturaleza de la secuencia blanco y en la composición proteica de los complejos efectores. La ruta del RNA de interferencia (RNAi) se inicia cuando Dicer genera pequeños RNA de interferencia (siRNA) que se unen por complementariedad al mRNA para su degradación, utilizando el complejo RISC. De manera natural, los siRNA se originan de transposones y virus que producen RNAdc durante su replicación, así como también de otras secuencias repetidas transcritas bidireccionalmente. Algunas de las enzimas que conforman la maquinaria del RNAi como Dicer, entre otras, son codificadas por familias multigénicas en varias especies y también participan en otros mecanismos de silenciamiento mediado por RNA. Los microRNA son otros RNA pequeños que pueden inducir silenciamiento al unirse al mRNA. Éstos se generan de manera general cuando Dicer procesa estructuras de horquilla compuestas de regiones no codificantes, en genomas de plantas y animales. Los miRNA se incorporan a un complejo similar a RISC y, dependiendo de su grado de complementariedad con el mRNA blanco, pueden tener represión traduccional o bien digerir el mRNA. El silenciamiento mediado por miRNA es esencial para el desarrollo de plantas y animales. La inducción artificial del RNAi mediante siRNA o miRNA ha sido adoptada como una herramienta para inactivar la expresión génica, tanto en células en cultivo como en organismos vivos. En esta revisión se muestra el gran progreso en el entendimiento de los mecanismos que participan en la regulación génica mediada por RNA en animales y detalla algunos esfuerzos actuales para encauzar a estos mecanismos como una herramienta en la investigación y como posible terapia en enfermedades.


Assuntos
Humanos , MicroRNAs/metabolismo , Interferência de RNA/fisiologia , RNA Interferente Pequeno/metabolismo , MicroRNAs/genética , RNA Interferente Pequeno/genética
16.
Rev. invest. clín ; Rev. invest. clín;57(3): 434-441, may.-jun. 2005. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-632464

RESUMO

High risk human papillomavirus (HPV) infection is considered to be the most important etiological factor of Cervical Uterine Cancer. In order to determine the global expression pattern and to identify possible molecular markers of cervical cancer, cDNA arrays with probe sets complementary to 8,000 human genes were used to examine the expression profiles among 5 cell lines derived from human cervical cancer, three HPV16(+) tumor samples and three normal cervical tissues HPV(-). The levels of expression of different cellular processes were identified. Hierarchical clustering was performed and the gene expression using RT-PCR was confirmed. Two genes were found to be consistently overexpressed in invasive cervical cancer biopsies; one of them, IL-6 was previously reported to be overexpressed in cervical cancer and one novel gene, MMP10, previously not known to be related to cervical cancer. Hierarchical clustering of the expression data revealed that samples with common HPV type infection grouped together, maybe this could mean that differences between HPV types could be indirectly determined by expression profiles.


La infección por virus de papiloma de alto riesgo (VPH) es considerada como el factor etiológico más importante del cáncer cérvico uterino (CaCU). Con el fin de determinar el patrón de expresión global e identificar algunos posibles genes marcadores del CaCU, se utilizaron microhileras de DNA que contenían 8,000 secuencias que codificaban para transcritos diferentes, para estudiar los perfiles de expresión de cinco líneas celulares derivadas de CaCU, tres muestras tumorales conteniendo VPH 16 y tres muestras normales negativas para la presencia de VPH. Se identificaron los niveles de expresión de genes relacionados con diferentes rutas metabólicas. Se llevó a cabo el análisis de agrupamiento jerárquico y posteriormente se confirmó la sobrexpresión de dos genes mediante RT-PCR. Estos dos genes se encontraron sobrexpresados en biopsias tumorales cervicales. Uno de ellos, el gen de IL6, que ha sido previamente reportado en relación con CaCU, así como el gen de la matriz-metaloproteasa 10 (MMP10) por primera vez relacionado con esta neoplasia. El análisis de agrupamiento jerárquico, además, reveló que las muestras que contienen el mismo tipo viral están asociadas, sugiriendo posibles diferencias en expresión entre tipos virales.


Assuntos
Adulto , Feminino , Humanos , Carcinoma de Células Escamosas/genética , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Proteínas de Neoplasias/genética , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/genética , Biomarcadores Tumorais/genética , Neoplasias do Colo do Útero/genética , Biópsia , Colposcopia , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/virologia , Linhagem Celular Tumoral/metabolismo , Linhagem Celular Tumoral/virologia , Colo do Útero/patologia , DNA Complementar/genética , DNA de Neoplasias/genética , DNA de Neoplasias/isolamento & purificação , /biossíntese , /genética , Metaloendopeptidases/biossíntese , Metaloendopeptidases/genética , Proteínas de Neoplasias/biossíntese , Pré-Menopausa , Infecções por Papillomavirus/metabolismo , Infecções por Papillomavirus/patologia , Infecções por Papillomavirus/virologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , RNA Mensageiro/genética , RNA Mensageiro/isolamento & purificação , RNA Neoplásico/genética , RNA Neoplásico/isolamento & purificação , Biomarcadores Tumorais/biossíntese , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/virologia
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