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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.
61

Análise proteômica de proteínas sintetizadas em resposta acisplatina em células de adenocarcinoma de pulmão humano resistentes e sensíveis a droga

Dutra, Cristine de Souza January 2018 (has links)
O câncer de pulmão está entre os mais frequentes na população mundial e é o responsável pelo maior número de mortes relacionadas ao câncer. Como o câncer de pulmão é identificado em estágios avançados de desenvolvimento, o principal tratamento é baseado em quimioterapia utilizando moléculas derivadas de platina, principalmente a cisplatina (CDDP). A CDDP é capaz de formar ligações cruzadas no DNA resultando em morte celular, porém muitos pacientes apresentam tumores que são resistentes ao tratamento com CDDP. Esta resistência é uma das principais barreiras para o sucesso do tratamento do câncer de pulmão através de quimioterapia. Para entendermos melhor os mecanismos envolvidas na resistência a CDDP em células de câncer de pulmão, foram utilizadas células sensíveis (A549) e resistentes a CDDP (A549/CDDP) para a identificação de proteínas recém-sintetizadas em resposta ao tratamento com a droga através da técnica BONCAT. Através desta técnica foi possível a identificação de 173 e 136 proteínas reguladas por CDDP nas células A549 e A549/CDDP, respectivamente As proteínas identificadas estão relacionadas a diversos mecanismos moleculares distintos que potencialmente estão envolvidos na resposta a CDDP, como por exemplo splicing alternativo, resposta a estresse oxidativo, manutenção do telômero, regulação da apoptose e reorganização do citoesqueleto. Os resultados mostram que as células A549/CDDP são menos suscetíveis ao dano no DNA causado por CDDP do que as células sensíveis, A549. Além disso, as células A549/CDDP são capazes de aumentar a expressão de proteínas capazes de combater as espécies reativas de oxigênio geradas devido a presença de CDDP. Além disto, CDDP é capaz de induzir diferentes vias apoptóticas em células com diferentes sensibilidades à droga. Nas células A549, CDDP induz a ativação da via extrínseca enquanto que nas A549/CDDP ela é capaz de induzir a ativação da via intrínseca de apoptose. Portanto, nosso estudo foi capaz de fornecer evidencias de proteínas e vias que são diferencialmente expressas e ativadas após o tratamento com CDDP. / Lung cancer is among the most frequent cancer in the world population and it is the leading cause of cancer-related deaths. Since lung cancer is identified in advanced stages of development, the main treatment is based in chemotherapy using platinum containing compounds, mainly cisplatin (CDDP). CDDP is able to crosslink with DNA leading to cell death, however many patients show tumor that are resistance to CDDP. This resistance is one of the main barriers for the success of lung cancer treatment by chemotherapy. To understand the mechanisms involved in CDDP resistance in lung cancer, we used CDDPsensitive (A549) and –resistant (A549/CDDP) cells to identify the newly synthesized proteins in response to drug exposure by BONCAT technique. It was possible the identification of 173 and 136 proteins regulated by CDDP in A549 and A549/CDDP cells, respectively. The identified proteins were related to several distinct molecular mechanisms potentially involved in CDDP response, including alternative splicing, response to oxidative stress, telomere maintenance, apoptosis regulation and cystoskeleton reorganization. Our results showed that A549/CDDP cells are less susceptible to DNA damage caused by CDDP than A549 cells. A549/CDDP also are able to increase the expression of proteins that combat the reactive oxygen species generated due to CDDP presence. In addition, CDDP induces different apoptotic pathways in drug-sensitive and resistant cell. In the A549 cells, CDDP induces the activation of the extrinsic pathway, while in A549/CDDP cells CDDP induces the intrinsic apoptotic pathway. So, our study was able to provide evidence of proteins and pathways that are differentially express and activated after CDDP treatment.
62

Immunospecific albumin microspheres as a drug delivery system for cisplatin and 5-fluorouracil for the treatment of ovarian adenocarcinoma

Truter, Ernest John 17 May 2017 (has links)
Ovarian carcinoma is considered to be the most deadly of the gynaecological malignancies which in its earliest stages is usually asymptomatic. The unsatisfactory survival rates of patients on conventional chemotherapy regimens, necessitates vehicles capable of carrying cytotoxic agents directly to the malignant cells. This mode of targeted delivery allows for efficient tumour cell kill whilst sparing surrounding normal tissue and substantially reducing side-effects. This project examined the possible therapeutic role of a targetable sustained drug delivery system, albumin immunomicrospheres containing the chemotherapeutic agents, cisplatin and 5-fluorouracil, for the treatment of ovarian adenocarcinoma. A rodent cell line, as a model, has proved to be similar to its human counterpart and also has shown to be transplantable from one animal to another. Such a model could therefore be useful for performing experiments relating to drug delivery targetability and therapeutic trials, as well as survival studies, in cases of ovarian adenocarcinoma. In particular, this project examines the efficacy of the immunospecific microspheres containing the drugs in a highly concentrated form, administered intraperitoneally and targeted to an ovarian adenocarcinoma, in an attempt to enhance tumour cell kill whilst largely sparing surrounding normal tissue. It is widely recognized that the effectiveness of most chemotherapeutic drugs would be enhanced if they were to act selectively where they are needed. In order to achieve a therapeutically relevant dose in tumour cells, the amount of drug required usually proves also to be highly toxic to normal tissues. It was postulated that, to overcome the above, it may be feasible to develop a sustained immunospecific drug delivery system to optimize the action of cisplatin and 5-fluorouracil at the target site. With the attainment of the above, it was further postulated that higher doses of drugs could be delivered to the target area effecting higher tumour cell kill, that less normal tissue damage should occur and that toxic side effects of the drugs should be reduced. The rationale for selecting combination therapy of cisplatin and 5-fluorouracil is that, although it has been inferred that DNA intrastrand and interstrand cross-links produced by the cisplatin often repair, this repair can be blocked by 5-fluorouracil by inhibition of thymidylate synthetase, thus preventing DNA strand repair. Albumin immunomicrospheres are relatively innocuous in terms of toxicity, non-antigenic and are capable of accommodating chemotherapeutic agents in a non-specific fashion. We showed that they were capable of a 0. 94% entrapment of 5-fluorouracil and 1.23% cisplatin. Delivery of these drugs at a target site, and at these concentrations, should effect extensive cell kill. As the microspheres are chemically stable and can be manipulated to offload the entrapped drugs satisfactorily, in vitro drug release profiles were performed employing immunospecific microspheres directed towards its target cells. Slow degradation of the drug- containing albumin immunomicrospheres showed that 0.283 μg cisplatin/ml plasma and 0. 799 μg 5-fluorouracil/ml plasma could be made available at the target site over a 14-day period. These concentrations could be maintained over at least another 14 days and effect tumour cell kill satisfactorily. In order to assess the tumour cell kill, we performed clonogenic assays, cell survival growth curves, MTT cytotoxicity assays and assessed the induction of micronuclei in the tumour cells. The synergism between 5-fluorouracil and cisplatin showed a modulation of cisplatin cytotoxicity and total tumour cell kill was achieved at concentrations of 0.5 μg/ml 5-fluorouracil and 0.1 μg/ml cisplat in at the target site. The above-mentioned evidence of effective targeting of the drugs was then investigated in female Wistar rats with ovarian adenocarcinoma to assess comparative survival times when treated with free drugs or immunospecific albumin microspheres containing the drugs. Animals given a free drug dose of 5 mg/kg cisplatin and 20mg/kg 5-fluorouracil, followed by a repeat dose at the same concentrations 7 days later showed that only 14% of the animals survived a 90-day trial period. Animals given an intraperitoneal bolus dose of immunomicrospheres at a dose of 1 O mg/kg cisplatin and 40 mg/kg 5-fluorouracil showed that 60% of the animals survived the 90-day trial period. This data indicated to us that the survival probability of animals treated with drug-containing immunomicrospheres was substantially superior to other protocols employed in this study.
63

Podoplanin Is a Highly Sensitive and Specific Marker to Distinguish Primary Skin Adnexal Carcinomas From Adenocarcinomas Metastatic to Skin

Liang, Haohai, Wu, Hong, Giorgadze, Tamar A., Sariya, Dinesh, Bellucci, Kirsten S.W., Veerappan, Ranjitha, Liegl, Bernadette, Acs, Geza, Elenitsas, Rosalie, Shukla, Shruti, Youngberg, George A., Coogan, Philip S., Pasha, Theresa, Zhang, Paul J., Xu, Xiaowei 01 February 2007 (has links)
Distinction of primary skin adnexal carcinomas from cutaneous metastasis of adenocarcinomas is challenging. In this study, we evaluated podoplanin immunoreactivity in a series of primary skin adnexal tumors and adenocarcinomas metastatic to skin using a D2-40 antibody. The initial test series were composed of a total of 93 cases including 32 primary skin adnexal carcinomas, 46 benign primary adnexal tumors, and 15 cutaneous metastatic adenocarcinomas. We found that variable D2-40 reactivity was seen in all of the primary cutaneous carcinomas including sebaceous carcinomas (10/10), squamous cell carcinomas (10/10), porocarcinomas (4/4), trichilemmal carcinomas (4/4), skin adnexal carcinomas not otherwise specified (4/4), and in the majority of benign skin adnexal tumors. In contrast, no podoplanin immunoreactivity was seen in any of the 15 (0/15) cutaneous metastases. To confirm the initial findings and to further explore the utility of podoplanin reactivity in the distinction of these tumors, we also examined a test set of 35 unknown cases, including 21 adenocarcinomas metastatic to skin and 14 primary adnexal tumors, in a blinded fashion. In this test set of cases, podoplanin was negative in 22 cases and positive in 13 cases. Of the 22 podoplanin negative cases, 20 were proven to be metastatic adenocarcinoma. Of the 13 D2-40 positive cases, 12 were proven to be primary adnexal tumors. Our results suggest that podoplanin can be a useful tool to distinguish primary skin adnexal carcinomas form adenocarcinomas metastatic to skin with high sensitivity (94.5%) and specificity (97.2%).
64

Investigations on the pathogenesis and treatment of humoral hypercalcemia of malignancy using a canine hypercalcemic adenocarcinoma propagated in nude mice /

Rosol, Thomas John January 1986 (has links)
No description available.
65

Molecular and biological characteristics of stroma and tumor cells in colorectal cancer /

Gao, Jingfang, January 2008 (has links)
Diss. (sammanfattning) Linköping : Linköpings universitet, 2008. / Härtill 5 uppsatser.
66

Moléculas séricas relacionadas con la fisiopatología del adenocarcinoma pancreático como posibles marcadores tumorales

Ferri Iglesias, María José 27 September 2012 (has links)
Serum levels of several molecules associated to pancreatic adenocarcinoma (PDAC) pathophysiology are evaluated in this work, in order to determine their diagnostic value, distinguishing between PDAC patients and healthy controls (HC), different gastrointestinal tumours (GIT) and chronic pancreatitis (CP). Plasma mRNA levels in plasma of sialyltransferases (ST3Gal III and ST3Gal IV) could differentiate between HC and PDAC. Moreover, lower levels of ST3Gal III in early stages of PDAC compared to PDAC advanced stages were reported. The Glasgow Prognostic Score (GPS), inflammatory response quantification, differentiated between all the study groups. IGF-1 levels were lower in neoplasic groups of patient vs HC and CP. We assessed the diagnostic capacity of different markers alone or in combination and compared with that of CA 19.9. The best diagnostic capacity was found combining CEA, CA 19.9 and IGF-1 compared with CA 19.9 and it could be useful to distinguish PDAC from CP. / En este trabajo se analizan distintos parámetros séricos relacionados con la fisiopatología del adenocarcinoma pancreático (PDAC), para evaluar su uso como marcadores que permitan distinguir entre pacientes con PDAC y controles sanos (C), otras neoplasias del tracto gastrointestinal (ONEOS) y pancreatitis crónica (PC). La expresión en plasma de sialiltransferasas, ST3Gal III y ST3Gal IV diferencia entre controles y PDAC. Así mismo, los niveles de ST3Gal III permiten diferenciar en PDAC entre estadíos iniciales y metastáticos. El Glasgow Prognostic Score (GPS), medida de la respuesta inflamatoria, diferencia entre todos los grupos del estudio. Los valores de IGF-1 disminuyen en procesos neoplásicos vs C y PC.Se analiza la capacidad diagnóstica de los distintos parámetros individualmente y combinados entre sí respecto al CA19.9. La combinación de CA 19.9, CEA, IGF-1 aumenta la precisión diagnóstica frente al CA19.9 y podría ser útil para distinguir PDAC de PC.
67

Investigation of androgen receptor gene transfection into human prostate cancer cells : effects on cellular growth, apoptosis and adhesion

Nightingale, Joanna January 2000 (has links)
No description available.
68

An immunohistologic study of biological parameters in prostatic intraepithelial neoplasia and adenocarcinoma.

January 1999 (has links)
by Kwan Yiu Wing. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references (leaves 167-187). / Abstracts in English and Chinese. / ACKNOWLEDGMENTS --- p.IV / ABSTRACT --- p.1 / Chapter CHAPTER 1. --- INTRODUCTION --- p.5 / Chapter I. --- Epidemiology of Prostate Cancer --- p.5 / Chapter II. --- The Normal Prostate - Prostatic Anatomy --- p.9 / Chapter III. --- Pathology of Prostatic Cancers --- p.12 / Chapter CHAPTER 2. --- PROSTATIC INTRAEPITHELIAL NEOPLASIA --- p.16 / Chapter I. --- Introduction --- p.16 / Chapter II. --- "Definition, Characteristics and Grading" --- p.16 / Chapter III. --- Incidence and Prevalence of PIN --- p.26 / Chapter IV. --- Evidence Linking PIN with Prostatic Carcinoma --- p.27 / Chapter V. --- Conclusion --- p.37 / Chapter CHAPTER 3. --- HISTOLOGIC BIOMARKERS --- p.39 / Chapter I. --- p53 Protein --- p.39 / Chapter II. --- Proliferating Cell Nuclear Antigen (PCNA) --- p.44 / Chapter III. --- Ki-67 Antigen --- p.48 / Chapter IV. --- Epidermal Growth Factor Receptor --- p.49 / Chapter V. --- E-Cadherin --- p.51 / Chapter VI. --- CD44 --- p.54 / Chapter VII. --- nm23 --- p.58 / Chapter CHAPTER 4. --- OBJECTIVES OF STUDY --- p.62 / Chapter CHAPTER 5. --- MATERIALS AND METHODS --- p.63 / Chapter I. --- Materials --- p.63 / Chapter II. --- Methods --- p.71 / Chapter III. --- Interpretation of Immunostaining Results --- p.78 / Chapter IV. --- Statistical Analysis --- p.82 / Chapter CHAPTER 6. --- RESULTS --- p.83 / Chapter I. --- Immunohistochemical Results for p53 Protein --- p.83 / Chapter II. --- Results of Immunostaining of PCNA --- p.90 / Chapter III. --- Immunostaining and Quantitation of Ki-67 Expression --- p.97 / Chapter IV. --- Immunohistochemical Expression of EGFr --- p.105 / Chapter V. --- E-Cadherin --- p.110 / Chapter VI. --- CD44 --- p.115 / Chapter VII. --- Expression of nm23 in Prostatic Lesions --- p.122 / Chapter VIII. --- Correlation and Association of Expressions of All Biomarkers in Prostatic Lesions --- p.128 / Chapter CHAPTER 7. --- DISCUSSION --- p.132 / Chapter I. --- p53 Protein --- p.135 / Chapter II. --- PCNA --- p.137 / Chapter III. --- Ki-67 --- p.140 / Chapter IV. --- EGFr --- p.143 / Chapter V. --- E-Cadherin --- p.146 / Chapter VI. --- CD44 --- p.148 / Chapter VII. --- nm23 --- p.151 / Chapter VIII. --- Association between Biomarkers and Prostate lesions --- p.154 / Chapter CHAPTER 8. --- SUMMARY AND CONCLUSION --- p.157 / APPENDICES --- p.164 / Chapter I. --- Table of incidence and mortality rates of prostate cancer in the United States from 1973 to 1995 by race --- p.164 / Chapter II. --- Table of leading cancer deaths in Hong Kong from 1971 to 1996 --- p.165 / Chapter III. --- Table of incidence and mortality rate caused by prostate cancer in Hong Kong --- p.166 / Chapter IV. --- Reagents --- p.167 / REFERENCES --- p.169
69

The role of Cdx2 in Barrett's metaplasia

Colleypriest, Benjamin John January 2010 (has links)
Barrett's metaplasia describes a condition in which the stratified squamous epithelium of the oesophagus switches to intestinal type columnar epithelium. The molecular mechanisms underlying the switch to intestinal epithelium is poorly understood but the transcription factor CDX2 has been implicated in the pathogenesis of Barrett's metaplasia and is sufficient to provoke an intestinal metaplasia in the stomach of transgenic mice. To address the molecular basis of Barrett’s, I developed an innovative explant system for adult mouse oesophageal epithelium in which the full repertoire of stratified squamous cell types is maintained for prolonged culture periods. In adult oesophageal cultures, cells expressing p63, K14, K4 and loricrin were detected. The ability of Cdx2 to induce intestinal genes in this model as well as in a human oesophageal cell line and foetal mouse oesophageal cultures was assessed. Cdx2 was sufficient to induce intestinal markers in Het-1A cells and foetal oesophageal epithelium but not in adult oesophageal explants. Following infection with Cdx2, Het-1A cells expressed four intestinal genes, Cdx1, Muc2, villin and K20. Embryonic oesophagus responds similarly and Muc2 and villin mRNA and Muc2 protein were detected. In contrast, infection of adult oesophageal explants did not provoke the expression of intestinal genes. These data suggest that additional factor(s) to Cdx2 are required in the conversion of adult oesophagus towards an intestinal phenotype as seen in Barrett's metaplasia. HNF4α is a candidate factor to cooperate with Cdx2 in intestinal development and therefore Barrett's metaplasia. Herein I demonstrate that HNF4α is sufficient to induce a columnar phenotype and the expression of intestinal genes within adult squamous oesophageal cells. The resultant phenotype is consistent with that seen in Barrett's metaplasia. Furthermore HNF4α and Cdx2 synergise to further enhance intestinalisation. This data suggests a hitherto unknown potential role for HNF4a in Barrett’s metaplasia.
70

Expressão imuno-histoquímica de metaloproteinase de matriz-9 (MMP-9) e de inibidor tecidual de metaloproteinase-1 (TIMP-1) em neoplasias de glândulas salivares /

Guterres, Micheline Bica January 2012 (has links)
Orientador: Yasmin Rodarte Carvalho / Coorientador: Luiz Eduardo Blumer Rosa / Banca: Adriana Aigotti Haberbeck Brandão / Banca: Carlos Eduardo Dias Colombo / Resumo: Os tumores de glândulas salivares apresentam uma grande diversidade celular, morfológica e de comportamento, tornando muitas vezes difícil seu diagnóstico, tratamento e prognóstico. Um componente importante desses tumores é a matriz extracelular, cuja remodelação é regulada por enzimas como as metaloproteinases da matriz (MMPs) e seus inibidores teciduais (TIMPs). O objetivo deste estudo foi avaliar a presença e expressão de MMP-9 e TIMP-1 em neoplasias de glândulas salivares. Foram estudados 20 casos de adenoma pleomórfico (AP), 05 de mioepitelioma (MIO), 17 de carcinoma mucoepidermóide (CME), 10 de adenocarcinoma polimorfo de baixo grau de malignidade (APBG) e 08 de carcinoma adenóide cístico (CAC), que foram selecionados dos arquivos do laboratório de Patologia Cirúrgica da FOSJC/UNESP. O material foi submetido à reação imuno-histoquímica para detecção de MMP-9 e TIMP-1, pelo método da estreptavidina-biotina peroxidase. Foi feita avaliação semiquantitativa da marcação e os dados foram submetidos à analise estatística descritiva e inferencial utilizando o programa Minitab (versão 16.0). Foram aplicados os testes Mann-Whitney e de sinais de postos de Wilcoxon, com nível de significância de 5%. Verificou-se que existe variação da expressão dos marcadores entre as diversas estruturas de cada lesão, com predomínio de TIMP-1 sobre MMP-9. Entre as neoplasias, observou-se maior expressão de TIMP-1 no AP, no CME e no CAC e de MMP-9 no MIO e no APBG, porém, sem diferença estatisticamente significante. Na comparação da marcação para cada anticorpo, entre lesões benignas e malignas, não se observou diferença estatisticamente significativa. Concluiu-se que a maioria das neoplasias de glândula salivar apresenta MMP-9 e TIMP-1 e que o grau de expressão dessas proteínas é... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The salivary gland tumors present very diverse cellular morphology and behavior, often making their diagnosis, treatment and prognosis difficult. An important component of tumors is the extracellular matrix, which is regulated by remodeling enzymes such as matrix metalloproteinases (MMPs) and their inhibitors (TIMPs). The objective of this study was to evaluate the role of MMP-9 and TIMP-1 in salivary gland neoplasms. We studied 20 pleomorphic adenomas (PA), 05 myoepitheliomas (MIO), 17 mucoepidermoid carcinomas (MEC), 10 polymorphous low-grade adenocarcinomas (PLGA) and 08 adenoid cystic carcinomas (ACC), which were selected from the files of the Laboratory of Surgical Pathology from FOSJC / UNESP. The material was subjected to immunohistochemical staining for detection of MMP-9 and TIMP-1 by the method of the streptavidin-biotin peroxidase. A staining semiquantitative assessment was made and the data were submitted to descriptive and inferential statistical analysis using Minitab (version 16.0). We applied the Mann-Whitney and Wilcoxon signs of posts tests, with a significance level of 5%. It was found that there is variation in the expression of markers among the various structures of each lesion, with a predominance of TIMP-1 over MMP-9. Among the tumors, we observed greater expression of TIMP-1 in PA, MEC and ACC and of MMP-9 in MIO and PLGA, however, any statistically significant difference has not been observed. Comparing the labeling for each antibody among benign and malignant lesions, there was no statistically significant difference. It was concluded that most of the salivary gland neoplasms express MMP-9 and TIMP-1 and that the degree of expression of these proteins is variable among the structures of the same lesion and among the various salivary neoplasms, regardless of their benign... (Complete abstract click electronic access below) / Mestre

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