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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Imunoexpressão de CXCL12, BCL-2 e MMP-9: Sua relevância no comportamento biológico de neoplasias de glândulas salivares

Santos, José Matheus Alves dos 18 August 2016 (has links)
Submitted by Jean Medeiros (jeanletras@uepb.edu.br) on 2018-05-17T13:27:08Z No. of bitstreams: 1 PDF - José Matheus Alves dos Santos.pdf: 29393004 bytes, checksum: eb8fee7ed5d16296c35d9765252c2ff2 (MD5) / Approved for entry into archive by Secta BC (secta.csu.bc@uepb.edu.br) on 2018-05-23T16:59:28Z (GMT) No. of bitstreams: 1 PDF - José Matheus Alves dos Santos.pdf: 29393004 bytes, checksum: eb8fee7ed5d16296c35d9765252c2ff2 (MD5) / Made available in DSpace on 2018-05-23T16:59:28Z (GMT). No. of bitstreams: 1 PDF - José Matheus Alves dos Santos.pdf: 29393004 bytes, checksum: eb8fee7ed5d16296c35d9765252c2ff2 (MD5) Previous issue date: 2016-08-18 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Introduction: Proinflammatory cytokines or chemokines are important regulators of cell trafficking and adhesions. The chemokine CXCL12 (C-X-C motif chemokine ligand 12) binds primarily to CXCR4 receptor, regulating intracellular signals, through several ways, related to important events in tumorigenesis as chemotaxis, cell survival, angiogenesis, proliferation, invasion and metastasis. There are insuficient informations in scientific literature about the CXCL12 in relation to survival or apoptotic markers (Bcl-2) and invasion/metastasis (MMP-9) in tumor cells of salivary gland neoplasm. Methods: In 30 pleomorphic adenomas (PA) and 30 mucoepidermoid carcinomas (MCE) were collected clinical and pathological data and analyzed in relation to the immunohistochemical expression, through the estreptovidin-biotin peroxidase method, of CXCL12, Bcl-2 and MMP-9 antibodies. Results: it was observed higher expression of CXCL12 in MCE than in PA (p = 0.001), while in PA there has been greater expression of Bcl-2 (p = 0.031). The MMP-9 was negative in most cases of the sample. Conclusion: it was concluded that the CXCL12 is not associated with the Bcl-2 and MMP-9 expression. The chemokine can be related to pathogenesis of mucoepidermoid carcinomas, whereas the Bcl-2 can be related to tumoral pathogenesis of pleomorphic adenomas. MMP-9 does not appear to play a role in the pathogenesis of the sample. / Introdução: As citocinas pró-inflamatórias ou quimiocinas são importantes reguladores das interações e adesões celulares. A quimiocina CXCL12 (C-X-C motif chemokine ligand 1) liga-se principalmente ao receptor CXCR4, regulando sinalizações intracelulares, através de várias vias, relacionadas a eventos importantes na tumorigênese como a quimiotaxia, proliferação e sobrevivência celular, angiogénese, invasão e metástase. Existe pouca informação na literatura científica sobre a relação da CXCL12 com marcadores de sobrevivência ou apoptóticos (Bcl-2) e de invasão/metástase (MMP-9) em neoplasias de glândulas salivares. Métodos: Em 30 adenomas pleomórficos (AP) e 30 carcinomas mucoepidermoides (CME) foram coletados dados clínico-patológicos os quais foram analisados em relação à expressão imunistoquimica, por meio do método estreptovidina - biotina peroxidase, dos anticorpos CXCL12, Bcl-2 e MMP-9. Resultados: observou-se maior expressão da CXCL12 no CME do que no AP (p = 0,001), enquanto que em AP houve maior expressão de Bcl-2 (p=0,031). A MMP-9 foi negativa na maioria dos casos da amostra. Conclusão: Conclui-se que a expressão da CXCL12 não parece estar associada com a Bcl-2 e MMP-9. A quimioquina pode ser relacionada com a patogênese de carcinomas mucoepidermóides, ao passo que a proteína Bcl-2 pode ser relacionada com a patogênese de adenomas pleomórficos. A MMP-9 não parece exercer um papel na patogenia da amostra avaliada.
2

Inibição simultânea dos genes antiapoptóticos Bcl-2 e Bcl-XL em células de leucemia  linfoide aguda e células de linfoma do manto mediante RNA de interferência / Simultaneous inhibition of antiapoptóticosBcl-2 and Bcl-XL genes acute lymphocytic leukemia and mantle cell lymphoma by RNA interference

Faustino, Viviane Dias 06 November 2012 (has links)
As estatísticas relacionadas aos cânceres hematológicos indicam que a incidência e mortalidade dessas doenças têm aumentado ao longo dos anos. Embora a maioria dos casos de linfomas e leucemias não possua etiologia definida, sugere-se que fatores genéticos possam estar envolvidos. Nesse contexto, destaca-se a família de proteínas Bcl-2, divididas em anti e pró-apoptóticas. Os genes Bcl-2 e Bcl-XL, membros de uma nova classe de oncogenes, que atuam no mecanismo de morte celular das células cancerígenas, sobretudo apoptose, a qual é controlada por numerosos sinais intra e extracelulares. Uma nova estratégia para o tratamento desta doença inclui a terapia gênica mediada por RNA de interferência, que silencia importantes genes, a exemplo dos genes da família Bcl-2. Visto que o silenciamento isolado de um único gene pode não ter resultados expressivos, o presente trabalho teve por objetivo desenhar um RNA de interferência (RNAi) homólogo a dois tipos distintos de RNA mensageiro (RNAm) e inibir simultaneamente os genes Bcl-2 e Bcl-XL,assim como testar a inibição isolada dos mesmos. Amostras de linhagem tumoral Jurkat e Granta-519 foram avaliadas após transfecção com os seguintes RNA:i Bcl-2,Bcl-XL, Bcl-2/Bcl-XL,Bcl-2+Bcl-XL e scramble. Os nossos achados evidenciam que, na linhagem Granta-519, a sequência do RNAi Bcl-2 inibe, isoladamente ou conjugado ao Bcl-XL, o gene Bcl-2. Deste modo, o RNAi Bcl-2 apresenta-se mais eficiente no mecanismo de silenciamento gênico, uma vez que propicia a morte celular frente a toxicidade do quimioterápico etoposide. / The hematological cancer statistics indicates that its incidence and mortality have increased over the years. Although most cases of lymphomas and leukemias has no definite etiology however is suggested that genetic factors may be involved. In this context there is the Bcl-2 proteins family divided into anti-apoptotic and pro-apoptotic which Bcl-2 and Bcl-XL genes are members of a new class of oncogenes that act in cancer cells death mechanisms, especially apoptosis, that is controlled by numerous intra-and extracellular signals. Among new strategies to treat hematological cancer includes gene therapy mediated by RNA interference, which can decrease expression of genes like Bcl-2 family components. Studies of single gene silencing have not shown significant results so this study aimed to design an RNA interference (iRNA) homologous to two distinct types of messenger RNA (mRNA) and inhibit both genes Bcl-2 and Bcl-XL -XL as well as test the inhibition. Commercial cells Jurkat and Granta-519 were evaluated after transfection with iRNA as follows: Bcl-2, Bcl-XL, Bcl-2/Bcl-XL, Bcl-2+Bcl-XL and scramble. Our findings show that in Granta-519 cell line Bcl-2 RNAi sequence inhibits, alone or conjugated to Bcl-XL, Bcl-2 gene. Thus RNAi Bcl-2 appears more effective in gene silencing mechanism as it promotes cell death due chemotherapeutic agent etoposide toxicity.
3

Etablierung der Echtzeit-Fluoreszenz-PCR zur Bestimmung des BCL-2-Transkriptes bei akuten myeloischen Leukämien

Liu, Kaishan 22 April 2003 (has links)
Das BCL-2 Gen wurde als Onkogen der t (14;18)(q32;q21)-Translokation bei follikulären Non- Hodgkin-Lymphomen identifiziert. Die biologische Wirkung des BCL-2 Proteins liegt in der Hemmung der Apoptose. Bei der AML wird eine vermehrte BCL-2 Expression und eine dem- entsprechend verminderte Apoptose bei unreifen malignen myeloischen Vorläuferzellen gefun- den. Diese Krankheit ist teilweise auch chemoresistent. Goldstandard der Induktionstherapie bei AML ist eine Kombination aus Ara-C und Idarubicin, welche Doppel- und Einzelstrang- brüche der DNA induzieren. Apoptose der Leukämiezellen wird durch Schädigung der DNA ausgelöst. BCL-2 kann die Zellen durch Hemmung der Apoptose schützen, indem es die Cy- tochrom-C-Freisetzung blockiert. Darüber hinaus befinden sich die BCL-2- überexprimierenden Zellen in der G0-Phase und sprechen dabei schlecht auf die Chemothera- pie an. Deshalb stellt BCL-2 den Leukämiezellen "doppelten" Schutz zur Verfügung. BCL-2 spielt somit eine wichtige Rolle bei der Chemoresistenz. Ob ein Therapieprotokoll in der Be- handlung der AML effektiv ist, schlägt sich in der Kinetik der zunehmenden oder abnehmen- den BCL-2-Transkripte nieder. Zur Kontrolle des BCL-2-Transkriptes ist die quantitative PCR der qualitativen PCR überlegen. Die Quantifizierung dieses Transkriptes wurde mittels Echtzeit-Fluoreszenz-PCR realisiert. Bei der Echtzeit-Fluoreszenz-PCR wird die Reaktion im geschlossenen Reaktionsgefäß durchge- führt, sodass die Gefahr von Kontamination minimiert werden kann. Da keine Post-PCR Schrit- te nötig sind, wird die Überprüfung zahlreicher Proben durch ein 96-well-Format innerhalb eines Laufes ermöglicht. Die Echtzeit-Fluoreszenz-PCR garantiert ihre Spezifität durch eine spezifi- sche Sonde-Zielsequenz-Bindung und erlaubt eine exakte Quantifizierung der BCL-2- Transkriptzahl. In der vorliegenden Arbeit wurde die BCL-2-Expression in 53 AML-Fällen mittels Echtzeit- Fluoreszenz-PCR untersucht. Das ?-Actin Gen wurde als Referenzgen benutzt. Für die BCL-2- Expression wurde eine Ratio aus der Transkriptzahl des BCL-2 Gens und des ?-Actin Gens ge- bildet. Bei 53 AML-Fällen, die den sieben AML-Subtypen zugeordnet werden konnten(FAB M0-M7), konnte eine BCL-2-Expression nachgewiesen werden. Trotz der unterschiedlich hohen BCL-2-Expression bei diesen Patienten, ergab sich keine signifikante Korrelation zwischen der BCL-2-Expression und den FAB-Subtypen. Außerdem wurde die BCL-2-Expression in T- Zellen, B-Zellen und Granulozyten aus 5 AML-Patienten nachgewiesen. Die BCL-2-Expression wurde nicht von den Subpoplationen der mononukleären Zellen wie z.B. T-Zellen, B-Zellen, Granulozyten beeinflusst. Bei sieben Patienten wurden Proben im Verlauf untersucht. Dabei korrelierte eine hohe oder ansteigende BCL-2-Expression mit einem Rückfall der AML. Die Anzahl der untersuchten Proben im Verlauf ist jedoch zu klein, um definitive Schlußfolgerungen zu ziehen. Eine prospektive Untersuchung von größeren Patientenzahlen erscheint sinnvoll. / The bcl-2 oncogene was discovered by virtue of its association with the translocation, t(14;18) (q32;q21), observed in most follicular lymphomas. The bcl-2 protein is a 26 kDa integral membrane protein which functions by enhancing cell viability through the inhibition of apoptotic death. Acute myeloid leukemia is a lethal malignant disease characterized by an abnormal proliferation and differentiation of myeloid progenitor cells. The bcl-2 oncogene contributes to leukemogenesis by prolonging the life span of defected progenitor cells. Although the expression of bcl-2 in blast cells of acute myeloid leukemia is heterogeneous, a significant proportion of blast cells are shown to have high bcl-2 levels. The highest bcl-2 levels are found in cells that grow autonomously in vitro and also in blast cells expressing the CD34 surface antigen. These groups of AML patients are tranditionally the ones in which the prognosis is poor, because most of the chemotherapeutic agents like cytosine-arabinoside (Ara-C) exert their effect by triggering apoptosis. The high level of the bcl-2 gene that inhibits apoptosis is implicated in the resistance of AML blast cells to chemotherapy and leads to unfavorable prognosis. In this study, a real time fluorescence PCR assay was used to monitor the expression of the bcl-2 transcript in the therapeutic course of AML patients. By applying this rapid new developed quantitative method, the changes of the bcl-2 transcript with chemotherapy can help to evaluate the efficacy of therapeutic interventions in AML. The real time fluorescence PCR has many advantages over traditional measures. First, the assay is extremely rapid because post-PCR processing steps are unnecessary. All relevant data are collected real time during the course of a 2h PCR cycle program; data analysis can be completed in less than 10 min. Second, the assay from reaction set-up to data collection and analysis is a closed-tube system, which reduces the risk of false positive resulting from PCR product carry- over contamination and eliminates variation from additional pipetting steps. Finally, the real time fluorescence PCR is highly specific for the gene target of interest. Here the expression levels of the bcl-2 gene were measured in 53 patients with acute myeloid leukemia and normalized by ?-actin, a house-keeping gene expression as endogenous reference. The bcl-2/?-actin ratio from the 53 patients with AML was various, but not related to FAB subtypes. And also, this transcript ratio was not affected by mononucleated cell types. The samples from seven patients were measured to evaluate the association between the bcl-2 expression and the responsiveness of AML patients to the chemotherapy. The high or gradual elevation of the bcl-2 expression demonstrated the loss of effect in update-therapy protocol and the relapse in AML patients. Although the amount of samples are not large enough to reach the final conclusion, it is of significance that a number of patients will be analyzed in the future.
4

Inibição simultânea dos genes antiapoptóticos Bcl-2 e Bcl-XL em células de leucemia  linfoide aguda e células de linfoma do manto mediante RNA de interferência / Simultaneous inhibition of antiapoptóticosBcl-2 and Bcl-XL genes acute lymphocytic leukemia and mantle cell lymphoma by RNA interference

Viviane Dias Faustino 06 November 2012 (has links)
As estatísticas relacionadas aos cânceres hematológicos indicam que a incidência e mortalidade dessas doenças têm aumentado ao longo dos anos. Embora a maioria dos casos de linfomas e leucemias não possua etiologia definida, sugere-se que fatores genéticos possam estar envolvidos. Nesse contexto, destaca-se a família de proteínas Bcl-2, divididas em anti e pró-apoptóticas. Os genes Bcl-2 e Bcl-XL, membros de uma nova classe de oncogenes, que atuam no mecanismo de morte celular das células cancerígenas, sobretudo apoptose, a qual é controlada por numerosos sinais intra e extracelulares. Uma nova estratégia para o tratamento desta doença inclui a terapia gênica mediada por RNA de interferência, que silencia importantes genes, a exemplo dos genes da família Bcl-2. Visto que o silenciamento isolado de um único gene pode não ter resultados expressivos, o presente trabalho teve por objetivo desenhar um RNA de interferência (RNAi) homólogo a dois tipos distintos de RNA mensageiro (RNAm) e inibir simultaneamente os genes Bcl-2 e Bcl-XL,assim como testar a inibição isolada dos mesmos. Amostras de linhagem tumoral Jurkat e Granta-519 foram avaliadas após transfecção com os seguintes RNA:i Bcl-2,Bcl-XL, Bcl-2/Bcl-XL,Bcl-2+Bcl-XL e scramble. Os nossos achados evidenciam que, na linhagem Granta-519, a sequência do RNAi Bcl-2 inibe, isoladamente ou conjugado ao Bcl-XL, o gene Bcl-2. Deste modo, o RNAi Bcl-2 apresenta-se mais eficiente no mecanismo de silenciamento gênico, uma vez que propicia a morte celular frente a toxicidade do quimioterápico etoposide. / The hematological cancer statistics indicates that its incidence and mortality have increased over the years. Although most cases of lymphomas and leukemias has no definite etiology however is suggested that genetic factors may be involved. In this context there is the Bcl-2 proteins family divided into anti-apoptotic and pro-apoptotic which Bcl-2 and Bcl-XL genes are members of a new class of oncogenes that act in cancer cells death mechanisms, especially apoptosis, that is controlled by numerous intra-and extracellular signals. Among new strategies to treat hematological cancer includes gene therapy mediated by RNA interference, which can decrease expression of genes like Bcl-2 family components. Studies of single gene silencing have not shown significant results so this study aimed to design an RNA interference (iRNA) homologous to two distinct types of messenger RNA (mRNA) and inhibit both genes Bcl-2 and Bcl-XL -XL as well as test the inhibition. Commercial cells Jurkat and Granta-519 were evaluated after transfection with iRNA as follows: Bcl-2, Bcl-XL, Bcl-2/Bcl-XL, Bcl-2+Bcl-XL and scramble. Our findings show that in Granta-519 cell line Bcl-2 RNAi sequence inhibits, alone or conjugated to Bcl-XL, Bcl-2 gene. Thus RNAi Bcl-2 appears more effective in gene silencing mechanism as it promotes cell death due chemotherapeutic agent etoposide toxicity.

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