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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

Integral Roles for the Tight Junction Protein Claudin-6 in Regulating Epidermal Homeostasis

Larivière, Nathalie 21 February 2014 (has links)
Forming and maintaining an intact epidermal permeability barrier (EPB) is necessary to mammalian health and dysregulation of this process can result in serious complications. Tight junctions (TJs) and their integral proteins the Claudins (Cldns) have both structural and signaling importance to the skin barrier and the latter is most likely mediated via Cldn tail interaction with cytoplasmic proteins. Given that the family member Cldn6 is known to be important to EPB function, we set out to determine the contribution of its cytoplasmic tail domain to TJ-mediated homoeostasis. Using transgenic mouse models, we overexpressed epidermal-targeted tail truncation mutants and assessed EPB formation and maintenance. We then used yeast 2-hybrid and quantitative proteomic approaches to identify proteins that interact with this tail region and to assess the downstream effects of overexpressing these proteins in human keratinocytes in culture. We demonstrate that a 10 amino acid region in the cytoplasmic tail is required for efficient epidermal maturation and injury repair and that our mouse models may be applicable to postnatal epidermal maturation and human skin aging studies. We show that in addition to the known interacting partner ZO1, the C-terminal tail of Cldn6 also binds FIZ1 (Flt3 interacting zinc finger protein-1), which we characterize for the first time as a mitogenic factor for keratinocytes. FIZ1 stimulates autocrine pathways involving secreted heparin-binding factors IGFBP3 and DKK1, sensitization to IGF signaling, MAP/ERK activation and increased G1 progression. Specific transcription factors, protein kinases and signaling scaffolds that we identified as novel FIZ1-binding partners likely mediate this signaling. Our studies on the Cldn6 cytoplasmic tail support the importance of this region for epidermal maturation and for maintenance of skin homeostasis throughout life. They also delineate the potential for tail interactors such as ZO1 and FIZ1 to act in concert with Cldns in TJ-based signaling networks to regulate the balance between proliferation and differentiation in keratinocytes. These findings provide new insight into the role of the Cldn6 cytoplasmic tail and will ultimately aid in the development of new diagnostic tools and therapeutic approaches for the treatment of skin conditions rooted in barrier defects.
2

Deciphering the Claudins that Mediate Renal Calcium Reabsorption

Desai, Prajakta V Unknown Date
No description available.
3

Les claudines dans le cancer colorectal : ciblage thérapeutique de la claudine-1 / Claudins in colorectal cancer : antibody targeting of claudin-1

Cherradi, Sara 21 November 2018 (has links)
En France, le cancer colorectal (CCR) est la 2ème cause de décès par cancer. Chez les patients, lorsque la tumeur est localisée, elle est réséquée par chirurgie. Toutefois, 50% des patients sont diagnostiqués à un stade métastatique, ces patients sont alors traités par chimiothérapie (FOLFOX/FOLFIRI), souvent en combinaison avec des thérapies ciblées incluant des anticorps tel que le Cetuximab (anti-EGFR) ou le Bevacizumab (anti-VEGF). Cependant, il reste encore environ 40% des patients qui ne répondent pas au traitement et l’une des causes les mieux établies est l'influence des mutations de la voie RAS en aval du récepteur à l'EGF sur la réponse au Cetuximab. C’est pourquoi l’identification de nouvelles cibles moléculaires accessibles aux anticorps permettrait le développement de nouveaux modèles de thérapie ciblée. Depuis peu, les Claudines ont suscité un intérêt pour le ciblage tumoral comme la claudin-4 dans les cancers de l’endomètre ou de la prostate. Très récemment, les résultats d'une étude clinique ont démontré que la combinaison d'un anticorps anti-Claudin-18.2, l'Acm IMAB362, avec la chimiothérapie prolongeait nettement la survie chez des patients atteints de cancer gastrique avancé.C’est dans cette optique que nous nous sommes focalisés sur les claudines dans le CCR. Tout d’abord en étudiant leur expression dans des échantillons de patients atteints de CCR métastatique. En analysant l’expression des claudines dans les nouveaux sous-types moléculaires, nous avons montré que certaines pouvaient avoir une valeur pronostique. Nous avons également identifié des claudines comme cibles thérapeutiques potentielles dans le CCR, parmi elles la CLDN1. En effet, nous avons montré que la forme membranaire de la CLDN1 était surexprimée dans les tumeurs primaires et métastases du CCR. Nous avons développé un anticorps monoclonal (Acm) ciblant les parties extracellulaires de la CLDN1. Nous avons montré que le ciblage thérapeutique de la CLDN1 par Acm provoquait un ralentissement significatif de la croissance, la migration et l'invasion des cellules tumorales aussi bien in vitro que in vivo. Afin d’améliorer l’efficacité du ciblage de la CLDN1 par Acm, nous avons couplé ce dernier avec une toxine, générant ainsi un Antibody Drug conjugated (ADC). Nous avons montré que le ciblage de la CLDN1 par un ADC diminuait la survie cellulaire in vitro en culture cellulaire 2D, mais également celle des sphéroïdes via un effet cytotoxique. Ce travail a permis d'établir la preuve de concept du ciblage de la CLDN1 aussi bien par Acm que par ADC. Afin de finaliser ce travail, ces résultats doivent être confirmés in vivo. A terme, nous espérons que ce ciblage puisse trouver sa place au sein de l’arsenal thérapeutique du CCR métastatique, en particulier chez les patients résistants aux traitements. / Colorectal cancer (CRC) is one of the major causes of cancer-related deaths in the Western world. When localized, CRC is often curable by surgery. However, 50% of patients are diagnosed at a metastatic stage, these patients are then treated with chemotherapy (FOLFOX / FOLFIRI), often in combination with targeted therapies including antibodies such as Cetuximab (anti-EGFR) or Bevacizumab (anti -VEGF). Despite these treatment, almost 40% of patients develop resistance. One of the most known resistance mechanisms of resistance is due to the RAS pathway downstream of the EGF receptor in response to Cetuximab. Therefore, more therapeutic options are required particularly by identifying new molecular targets that can be reached by antibodies. Recently, Claudines have generated interest as targets in cancer, such as claudin-4 in endometrial or prostate cancer. More recently, the results of a clinical study demonstrated that the combination of an anti-Claudin-18.2 antibody, IMAB362 mAb, with chemotherapy significantly prolonged survival in patients with advanced gastric cancer.Therefore, one of our aims was to focus on claudins in CCR. First, by studying their expression in metastatic CRC patient samples. We demonstrated the prognostic value of some claudins, after analyzing their gene expression in the new molecular subtype of CRC. Beside, we identified some claudins as potential therapeutic targets in CCR, among them claudin-1 (CLDN1). Indeed, we showed that the membrane form of CLDN1 is overexpressed in primary tumors and metastases of CRC. Therefore, we developed a monoclonal antibody (mAb) targeting the extracellular parts of CLDN1. We showed that therapeutic targeting of CLDN1 by mAb significantly decreased tumor cell growth, migration and invasion both in vitro and in vivo. In order to improve the efficiency of targeting CLDN1 by mAb, we conjugated it with a toxin, thus generating an Antibody Drug Conjugate (ADC). We showed that CLDN1 targeting by an ADC decreased cell survival in vitro in 2D cell culture, but also spheroids growth via a cytotoxic effect.This work demonstrated the proof of concept of CLDN1 targeting by both mAb and ADC. In order to achieve this work, the next steps remains on testing ADC affect in vivo models. CLDN1 is a good therapeutic target in the CCR. In the long term, we hope that its targeting can find its place within the therapeutic arsenal of metastatic CRC, particularly in treatment of resistant patients.
4

A expressão das claudinas 1, 3, 4, 7 e E-caderina em uma série de tumores de mama triplo-negativos

Cadore, Ermani January 2012 (has links)
INTRODUÇÃO: O câncer de mama é uma importante causa de morbimortalidade, é conhecido por ser uma doença heterogênea. A caracterização clínica e molecular de seus subtipos é fundamental para nortear o prognóstico e o tratamento dessas pacientes. Novos estudos são necessários na melhor caracterização dos tumores triplo-negativos. O estudo da expressão das claudinas pode auxiliar na caracterização desses tumores. OBJETIVO: Investigar a associação da expressão das claudinas 1, 3, 4 e 7 e E-caderina com variáveis clínico-patológicas e fatores prognósticos, em uma série de tumores de mama triplo-negativos (RE-, RP- e HER2-). MÉTODOS: 80 tumores triplo-negativos foram analisados por imunoistoquímica automatizada para as claudinas 1, 3, 4, 7 e E-caderina. A expressão imunoistoquímica foi avaliada pelo escore H (intensidade multiplicada pela porcentagem de marcação). Foram avaliadas as associações entre características clínico-patólogicas e o escore H. Para a avaliação prognóstica das pacientes, curvas de Kaplan-Meier foram construídas a partir dos dados de seguimento das pacientes e do escore H. RESULTADOS: Foi encontrada associação significativa entre o alto escore H da CLDN-1 (HCLDN-1) e pacientes mais idosas e com a presença de necrose, alto escore H da E-caderina (HE-CAD) em pacientes mais jovens e baixo escore H da CLDN-7 (HCLDN-7) e Ki67 positivo. Além disso, pacientes com elevado HCLDN-1 tiveram menor sobrevida geral. Por outro lado, o elevado HCLDN-3 apresentou uma tendência à associação com maior sobrevida geral e sobrevida livre de doença. CONCLUSÕES: A expressão diferencial das claudinas e E-caderina podem auxiliar na caracterização clinico-patológica dos tumores triplo-negativos. Além disso, as claudinas 1 e 3 parecem ser fatores prognósticos para esses tumores. / INTRODUCTION: Breast cancer is a major cause of morbidity and mortality, is known to be a heterogeneous disease. The clinical and molecular characterization of its subtypes is critical to guide the prognosis and treatment of these patients. Further studies are needed for the best characterization of triple-negative tumors. The study of the expression of claudinas can aid in the characterization of these tumors. OBJECTIVE: To investigate the association of expression of claudinas 1, 3, 4 and 7 and E-cadherin with clinicopathological variables and prognosis in a series of triple-negative breast cancers (ER-, PR- and HER2-). METHODS: 80 triple negative tumors were analyzed by automated immunohistochemistry for the claudins 1, 3, 4, 7 and E-cadherin. The immunohistochemical expression was assessed by H-Score (intensity multiplied by the percentage of staining). We evaluated the associations between clinicopathological characteristics and H-Score. For the prognostic assessment of patients, Kaplan-Meier curves were constructed from the follow-up data of patients and H-Score. RESULTS: We found a significant association between high H-Score of CLDN-1 (HCLDN-1) and older patients and the presence of necrosis, high H-Score of E-cadherin (H-CAD) in younger patients and low H-Score CLDN-7-(7-HCLDN) and Ki67 positive. Furthermore, patients with high-HCLDN1 had a lower overall survival. On the other hand, the high HCLDN-3 showed a trend toward association with greater overall survival and disease-free survival. CONCLUSIONS: Differencial expression of claudins and E-cadherin can help in clinic-pathological characterization of triple-negative tumors. Futhermore, claudin 1 and 3 appear to be prognostic factor for these tumors.
5

A expressão das claudinas 1, 3, 4, 7 e E-caderina em uma série de tumores de mama triplo-negativos

Cadore, Ermani January 2012 (has links)
INTRODUÇÃO: O câncer de mama é uma importante causa de morbimortalidade, é conhecido por ser uma doença heterogênea. A caracterização clínica e molecular de seus subtipos é fundamental para nortear o prognóstico e o tratamento dessas pacientes. Novos estudos são necessários na melhor caracterização dos tumores triplo-negativos. O estudo da expressão das claudinas pode auxiliar na caracterização desses tumores. OBJETIVO: Investigar a associação da expressão das claudinas 1, 3, 4 e 7 e E-caderina com variáveis clínico-patológicas e fatores prognósticos, em uma série de tumores de mama triplo-negativos (RE-, RP- e HER2-). MÉTODOS: 80 tumores triplo-negativos foram analisados por imunoistoquímica automatizada para as claudinas 1, 3, 4, 7 e E-caderina. A expressão imunoistoquímica foi avaliada pelo escore H (intensidade multiplicada pela porcentagem de marcação). Foram avaliadas as associações entre características clínico-patólogicas e o escore H. Para a avaliação prognóstica das pacientes, curvas de Kaplan-Meier foram construídas a partir dos dados de seguimento das pacientes e do escore H. RESULTADOS: Foi encontrada associação significativa entre o alto escore H da CLDN-1 (HCLDN-1) e pacientes mais idosas e com a presença de necrose, alto escore H da E-caderina (HE-CAD) em pacientes mais jovens e baixo escore H da CLDN-7 (HCLDN-7) e Ki67 positivo. Além disso, pacientes com elevado HCLDN-1 tiveram menor sobrevida geral. Por outro lado, o elevado HCLDN-3 apresentou uma tendência à associação com maior sobrevida geral e sobrevida livre de doença. CONCLUSÕES: A expressão diferencial das claudinas e E-caderina podem auxiliar na caracterização clinico-patológica dos tumores triplo-negativos. Além disso, as claudinas 1 e 3 parecem ser fatores prognósticos para esses tumores. / INTRODUCTION: Breast cancer is a major cause of morbidity and mortality, is known to be a heterogeneous disease. The clinical and molecular characterization of its subtypes is critical to guide the prognosis and treatment of these patients. Further studies are needed for the best characterization of triple-negative tumors. The study of the expression of claudinas can aid in the characterization of these tumors. OBJECTIVE: To investigate the association of expression of claudinas 1, 3, 4 and 7 and E-cadherin with clinicopathological variables and prognosis in a series of triple-negative breast cancers (ER-, PR- and HER2-). METHODS: 80 triple negative tumors were analyzed by automated immunohistochemistry for the claudins 1, 3, 4, 7 and E-cadherin. The immunohistochemical expression was assessed by H-Score (intensity multiplied by the percentage of staining). We evaluated the associations between clinicopathological characteristics and H-Score. For the prognostic assessment of patients, Kaplan-Meier curves were constructed from the follow-up data of patients and H-Score. RESULTS: We found a significant association between high H-Score of CLDN-1 (HCLDN-1) and older patients and the presence of necrosis, high H-Score of E-cadherin (H-CAD) in younger patients and low H-Score CLDN-7-(7-HCLDN) and Ki67 positive. Furthermore, patients with high-HCLDN1 had a lower overall survival. On the other hand, the high HCLDN-3 showed a trend toward association with greater overall survival and disease-free survival. CONCLUSIONS: Differencial expression of claudins and E-cadherin can help in clinic-pathological characterization of triple-negative tumors. Futhermore, claudin 1 and 3 appear to be prognostic factor for these tumors.
6

A expressão das claudinas 1, 3, 4, 7 e E-caderina em uma série de tumores de mama triplo-negativos

Cadore, Ermani January 2012 (has links)
INTRODUÇÃO: O câncer de mama é uma importante causa de morbimortalidade, é conhecido por ser uma doença heterogênea. A caracterização clínica e molecular de seus subtipos é fundamental para nortear o prognóstico e o tratamento dessas pacientes. Novos estudos são necessários na melhor caracterização dos tumores triplo-negativos. O estudo da expressão das claudinas pode auxiliar na caracterização desses tumores. OBJETIVO: Investigar a associação da expressão das claudinas 1, 3, 4 e 7 e E-caderina com variáveis clínico-patológicas e fatores prognósticos, em uma série de tumores de mama triplo-negativos (RE-, RP- e HER2-). MÉTODOS: 80 tumores triplo-negativos foram analisados por imunoistoquímica automatizada para as claudinas 1, 3, 4, 7 e E-caderina. A expressão imunoistoquímica foi avaliada pelo escore H (intensidade multiplicada pela porcentagem de marcação). Foram avaliadas as associações entre características clínico-patólogicas e o escore H. Para a avaliação prognóstica das pacientes, curvas de Kaplan-Meier foram construídas a partir dos dados de seguimento das pacientes e do escore H. RESULTADOS: Foi encontrada associação significativa entre o alto escore H da CLDN-1 (HCLDN-1) e pacientes mais idosas e com a presença de necrose, alto escore H da E-caderina (HE-CAD) em pacientes mais jovens e baixo escore H da CLDN-7 (HCLDN-7) e Ki67 positivo. Além disso, pacientes com elevado HCLDN-1 tiveram menor sobrevida geral. Por outro lado, o elevado HCLDN-3 apresentou uma tendência à associação com maior sobrevida geral e sobrevida livre de doença. CONCLUSÕES: A expressão diferencial das claudinas e E-caderina podem auxiliar na caracterização clinico-patológica dos tumores triplo-negativos. Além disso, as claudinas 1 e 3 parecem ser fatores prognósticos para esses tumores. / INTRODUCTION: Breast cancer is a major cause of morbidity and mortality, is known to be a heterogeneous disease. The clinical and molecular characterization of its subtypes is critical to guide the prognosis and treatment of these patients. Further studies are needed for the best characterization of triple-negative tumors. The study of the expression of claudinas can aid in the characterization of these tumors. OBJECTIVE: To investigate the association of expression of claudinas 1, 3, 4 and 7 and E-cadherin with clinicopathological variables and prognosis in a series of triple-negative breast cancers (ER-, PR- and HER2-). METHODS: 80 triple negative tumors were analyzed by automated immunohistochemistry for the claudins 1, 3, 4, 7 and E-cadherin. The immunohistochemical expression was assessed by H-Score (intensity multiplied by the percentage of staining). We evaluated the associations between clinicopathological characteristics and H-Score. For the prognostic assessment of patients, Kaplan-Meier curves were constructed from the follow-up data of patients and H-Score. RESULTS: We found a significant association between high H-Score of CLDN-1 (HCLDN-1) and older patients and the presence of necrosis, high H-Score of E-cadherin (H-CAD) in younger patients and low H-Score CLDN-7-(7-HCLDN) and Ki67 positive. Furthermore, patients with high-HCLDN1 had a lower overall survival. On the other hand, the high HCLDN-3 showed a trend toward association with greater overall survival and disease-free survival. CONCLUSIONS: Differencial expression of claudins and E-cadherin can help in clinic-pathological characterization of triple-negative tumors. Futhermore, claudin 1 and 3 appear to be prognostic factor for these tumors.
7

Studium biomarkerů karcinomu prsu po neoadjuvantní léčbě. / Breast cancer biomarkers after neoadjuvant therapy.

Skálová, Helena January 2020 (has links)
Chemotherapy is one of the basic therapeutic procedures of breast cancer (BC) which may precede and/or follow the surgical resection of a tumor as a part of neoadjuvant or adjuvant therapy. However, the selective pressure of chemotherapy on tumor cells may change their molecular and expression profile and thus also their chemosensitivity. The aim of our work was to document the expression changes of selected markers in BC after neoadjuvant chemotherapy, which may contribute to the understanding of the role of these proteins and genes in tumor response to chemotherapy and the development of chemoresistance. Immunohistochemical analysis of expression of standard BC markers [estrogen (ER) and progesterone receptors (PR), HER2 and proliferation activity (Ki67)] and intercellular junction proteins (claudin 1, 3 and 4, E- and N-cadherin) before and after neoadjuvant chemotherapy revealed a decrease of PR, Ki67 and claudin 3 expression and an increase of claudin 1 expression. The expression of ER, HER2, claudin 4, E- and N-cadherin proved to be stable. Assessment of standard BC markers is performed routinely during a bioptic investigation as a necessary factor for therapy indication. Our results support the current recommendations for the re-examination before indication of adjuvant chemotherapy. Claudins...
8

Imunoexpress?o das claudinas -1 e -7 em ameloblastomas e germes dentais humanos

Iglesias, D?borah Pitta Para?so 14 October 2008 (has links)
Made available in DSpace on 2014-12-17T15:32:16Z (GMT). No. of bitstreams: 1 DeborahPPI.pdf: 1504501 bytes, checksum: a7d060d1016a25d3b60f572c27bd03bc (MD5) Previous issue date: 2008-10-14 / We investigated the immunohistochemistry expression of claudins -1 and -7 in ameloblastoma and in human dental germs on the pattern of distribution (focal, regional or diffuse), the cells that expressed (if central or peripheral) and the location of that expression in the cell components recital membrane, cytoplasm and nucleus. Among the 29 cases of ameloblastoma, 24 were type solid and 6 unicystic. In 7 mandibular specimens of human fetuses found dental germs from the stage of bud to the crown. We note that the pattern of expression in the dental germs was variable for claudinas studied according to the cell type and stage of differentiation and was invariate only in the cells of stellate reticulum. In epithelium internal of enamel organ, claudin-1 has been decreasing with the progression of differentiation as to claudina-7 that was found in the cells of the peripheral papilla. For ameloblastoma the expression was more significant than that observed in dental germs. Fisher s exact test no found association between the expression of claudinas cells in central and peripheral and the type of ameloblastoma (solid or unicystic). Thus, in general the claudin-1 was positive in the central cell of 93,1% of the cases and in peripheral cells of 51,7%. The claudin-7 was expressed in the cells of all cases central and peripheral cells from 89,7%. For both claudins the distribution was predominantly diffuse cells both in central and peripheral cells. Given our findings it is suggested that the expression of claudins may be indicative of the involvement of these molecules in morphogenetics events culminating with the dental development and that possibly influence the development of neoplastic ameloblastoma / Investigamos a express?o imuno-histoqu?mica das claudinas -1 e -7 em ameloblastomas e germes dentais humanos, avaliando o padr?o de distribui??o (focal, regional ou difuso), as c?lulas que as expressavam (central ou perif?rica) e a localiza??o dessa express?o nos constituintes celulares considerando membrana, citoplasma e n?cleo. Dentre os 29 casos de ameloblastomas, 23 eram do tipo s?lido e 6 unic?sticos. Nos 7 esp?cimes mandibulares de fetos humanos observamos germes dentais desde a fase de capuz at? a fase de coroa. Constatamos que o padr?o de express?o nos germes dentais foi vari?vel para as claudinas estudadas de acordo com o tipo celular e est?gio de diferencia??o assemelhando-se apenas nas c?lulas do ret?culo estrelado. No epit?lio interno a express?o da claudina-1 foi decrescente com a progress?o da diferencia??o enquanto para a claudina-7 foi verificada nas c?lulas perif?ricas da papila. Para os ameloblastomas, de forma geral, a express?o foi mais significativa do que aquela observada nos germes dentais. Foi aplicado o teste estat?stico de Fisher o qual n?o demonstrou associa??o entre a express?o das claudinas nas c?lulas centrais e perif?ricas e o tipo do ameloblastoma (s?lido ou unic?stico). De uma maneira geral, a claudina-1 foi positiva nas c?lulas centrais de 93,1% dos casos e nas c?lulas perif?ricas de 51,7%. A claudina-7 esteve expressa nas c?lulas centrais de todos os casos e nas c?lulas perif?ricas de 89,7%. Para ambas as claudinas a distribui??o foi predominantemente difusa tanto nas c?lulas centrais como nas c?lulas perif?ricas. Diante dos nossos achados sugere-se que a express?o das claudinas pode ser indicativa da participa??o destas mol?culas nos eventos morfogen?ticos que culminam com a forma??o dental e possivelmente influenciam o desenvolvimento neopl?sico dos ameloblastomas
9

Oxidative stress and cell adhesion in skin cancer

Hintsala, H.-R. (Hanna-Riikka) 02 August 2016 (has links)
Abstract Skin is the largest organ in our body protecting us from ultraviolet radiation and xenobiotics. UV-radiation is a common cause of squamocellular carcinoma and melanoma of the skin that cause morbidity and mortality world wide. Reactive oxygen species are constantly formed by, for example, cellular respiration and UV-radiation, and they can readily react with virtually any macromolecule within cell structures causing damage to DNA, proteins and lipids. Oxidative stress (OS) is a homeostatic process that is dysregulated in cancer cells to their benefit. Nuclear factor erythroid-2-related factor 2 (Nrf2) is the main regulator of antioxidant response and it has been shown to be upregulated in various cancers enabling their survival and growth. By using immunohistochemistry we studied the change and prognostic significance of OS markers in melanoma from paraffin embedded patient samples. Nrf2 expression is increased in melanoma, associating with deeper invasion and a worse melanoma-specific outcome. In addition, epithelial-to-mesenchymal transition markers Slug, Twist and Zeb1 showed altered expression levels in relation to invasion and metastasis associating also with Nrf2. With the help of target inhibition molecules Vemurafenib and MEK-inhibitor CI-1040, In vitro study showed that BRAF- and NRAS-mutations might activate Nrf2. Furthermore, Nrf2-regulated antioxidant enzyme peroxiredoxin I showed decreased expression in malignant melanomas and metastases compared to benign naevi. Intriguing findings were made from the surrounding structures of melanomas e.g. loss of expression of an oxidative lesion marker 8-hydroxy-2’-deoxyguanosine in adjacent endothelial cells associated with worse melanoma-specific survival. Changes in the expression of adhesion molecules claudins 1-5 and 7 were studied in the progression of cutaneous squamous cell carcinomas and preneoplastic lesions. Change in claudin composition can alter epidermal permeability and cell polarity. Efficiency of oncological treatment modalities is frequently based on oxidative stress damage. Nrf2-inhibition could offer the means to increase the sensitivity of cancerous tissue to oxidative insults and hinder proliferative and survival signalling. Later research should focus on the relation of Nrf2 with other signalling and observations made from the tumour microenvironment. / Tiivistelmä Iho on elimistön suurin elin, ja se suojaa meitä auringon ultravioletti (UV)-säteilyltä ja muilta ulkoisilta tekijöiltä. UV-säteily on yhteinen etiologinen tekijä ihon levyepiteelikarsinoomalle ja melanoomalle, jotka aiheuttavat maailmanlaatuisesti paljon sairastavuutta ja kuolleisuutta. Reaktiivisia happiradikaaleja muodostuu esimerkiksi soluhengityksestä ja UV-säteilystä, ja ne voivat reagoida minkä tahansa makromolekyylin kanssa aiheuttaen vaurioita solun perimäainekseen, proteiineihin ja lipidirakenteisiin. Oksidatiivisen stressin (OS) säätely on tärkeä homeostaattinen prosessi, joka vinoutuu syöpäsolujen hyödyksi. Nuclear factor erythroid-2-related factor 2 (Nrf2) on antioksidanttivasteen pääsäätelytekijä, ja sen ilmentyminen on lisääntynyt useissa syövissä lisäten syöpäsolun selviytymistä ja kasvua. Tutkimme potilasaineiston ja immunohistokemian avulla OS:n merkkiaineiden muutoksia melanoomassa ja niiden merkitsevyyttä taudin ennusteelle. Nrf2:n ilmentyminen on lisääntynyt melanoomassa liittyen syvempään invaasioon ja huonompaan tautispesifiseen ennusteeseen. Lisäksi epiteliaali-mesenkymaalitransition merkkiaineiden, Slug, Twist ja Zeb1 ekspression muutoksia havaittiin syvyyskasvun ja metastasoinnin yhteydessä assosioituen myös Nrf2 ilmentymiseen. In vitro- tutkimus osoitti spesifisten inhibiittoreiden avulla, että BRAF- ja NRAS-mutaatiot saattavat aktivoida Nrf2 melanoomassa. Myös Nrf2:n säätelemän entsyymin peroksiredoksiini I:n ilmentyminen on vähentynyt melanoomassa ja metastaaseissa verrattuna hyvänlaatuisiin pigmenttiluomiin. Merkittäviä muutoksia havaittiin myös melanoomaa ympäröivistä rakenteista, esimerkiksi OS:n vauriomarkkerin 8-hydroksi-2’-deoksiguanosiinin vähentynyt ilmentyminen endoteelisoluissa liittyi huonompaan tautispesifiseen ennusteeseen. Lisäksi tutkimme soluväliliitosproteiinien klaudiinien 1–5 sekä 7 ilmentymistä levyepiteelikarsinoomissa ja niiden esiasteissa. Klaudiinien muutokset voivat vaikuttaa ihon permeabiliteettiin ja solujen polarisaatioon. Onkologisten hoitomuotojen teho perustuu usein happiradikaalien aiheuttamiin vaurioihin. Nrf2-inhibitio voisi tarjota keinon lisätä syöpäkudoksen herkkyyttä näille vaurioille sekä estää syöpäsolun selviytymissignalointia. Tulevat tutkimukset tulisivat keskittyä Nrf2 signaloinnin ja muun solusignaloinnin välisiin suhteisiin sekä havaintoihin kasvaimen mikroympäristön muutoksista.
10

Estudo da expressão das proteínas juncionais e dos fatores inflamatórios em pacientes com doença do refluxo gastroesofágico erosiva e não erosiva / Study of expressions of junctionals proteins and inflammatory factors in patients with gastro-oesophageal reflux disease and non-erosive reflux disease

Balbinotti, Silvana Sartori 07 July 2009 (has links)
Pacientes com doença do refluxo não erosiva apresentam sintomas típicos causados pelo refluxo do conteúdo gástrico para o esôfago. Entretanto, estes pacientes não apresentam alterações de mucosa visualizadas à endoscopia. O objetivo deste estudo é caracterizar a expressão de moléculas relacionadas à junção celular (claudinas 1, 3 e 4), da proteína pró-inflamatória Cox-2, da população global de linfócitos (CD45), população de linfócitos T (CD3), linfócitos B (CD20) e natural killer (CD57) em portadores de esofagite de refluxo erosiva e não erosiva. O estudo verificou que quanto mais intensa e crônica a inflamação no epitélio escamoso esofágico, menor a expressão das proteínas juncionais (claudinas 1 e 4), não alterando a expressão da claudina 3. Em relação à Cox-2 o estudo mostra aumento de sua expressão na forma erosiva da doença. Em relação à população de linfócitos, não foi detectada diferença significativa / Patients with non-erosive reflux disease conditions show typical symptons caused by the reflux of the gastric content to the esophagus. However, these patients dont show any alteration on the mucous membrane visualized trhough endoscopy. The aim of this study is to characterize the molecule expression related to the cell junction (claudins 1 , 3 and 4)the Cox 2 pro-inflamatory protein, the general population of (CD45) lymphocytes ,the population of lymphocytes T (CD3),the B (CD20) lymphocytes and the(CD57) natural killer in patients with erosive and non-erosive reflux esophagitis. The study found that the more intense and chronic the inflamation is in the esophageal squamous epithelium, less junction protein expressios (claudins 1 and 4) were found, not altering the 3 expressions of claudin 3. Regarding Cox 2, the study shows increase in its expression in the erosive form of the disease. Regarding the population of lymphocytes, no significant difference was detected

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