CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / O cÃncer colorretal(CCR) à altamente prevalente nos paÃses mais ricos e industrializados. As metaloproteinases de matriz (MMPs) sÃo importantes enzimas que facilitam a invasÃo e disseminaÃÃo do tumor em vÃrios tipos de cÃncer, inclusive o colorretal. Os inibidores teciduais de metaloproteinases (TIMPs) sÃo os principais inativadores fisiolÃgicos destas enzimas. Este estudo avaliou a expressÃo de metaloproteinase-2 (MMP-2), metaloproteinase-14 (MMP-14) e inibidor tecidual de metaloproteinases-2 (TIMP-2) no cÃncer colorretal. O imunomarcador CD68 foi utilizado para caracterizar a natureza das cÃlulas mononucleadas do estroma. Amostras teciduais de 50 casos de colectomias, devido ao cÃncer colorretal no perÃodo de 2004 a 2010, obtidas dos arquivos do Departamento de Patologia e Medicina Legal (DPML), Faculdade de Medicina da Universidade Federal do Cearà (UFC), foram analisadas. Realizou-se tissue microarrays e a seguir imuno-histoquÃmica para avaliar a expressÃo de MMP-2, MMP-14 e TIMP-2 de acordo com os seguintes escores baseados em outros relatos: 0= sem imunomarcaÃÃo ou raras cÃlulas marcadas (<5%); 1 = discreta marcaÃÃo na maioria (> 50%) das cÃlulas tumorais ou cÃlulas mononucleares do estroma, ou moderada marcaÃÃo em uma minoria de cÃlulas (<50 %); 2 =marcaÃÃo moderada na maioria (> 50%) de cÃlulas tumorais ou cÃlulas mononucleares ou intensa marcaÃÃo em minoria de cÃlulas (<50%); 3 = marcaÃÃo intensa na maioria (> 50%) de cÃlulas tumorais ou cÃlulas mononucleares. Observou-se relaÃÃo entre a expressÃo aumentada de MMP-14 em mononucleares de tumor primÃrio e casos sem metÃstases linfonodais (MMP-14, escores 2 e 3/N0 : 23/24 = 95%; N1-N3: 14/20 = 70%, p = 0,0353). No entanto, nenhuma relaÃÃo significativa foi encontrada entre a expressÃo de MMP-14, MMP-2 e TIMP-2 nos tumores primÃrios em cÃlulas cancerosas ou mononucleares e outros parÃmetros clÃnico-patolÃgicos. A imunoexpressÃo de MMP-2 foi negativa nas cÃlulas neoplÃsicas, em tumores primÃrios (47/47=100%) e metastÃticos (12/12 = 100%). A imunorreatividade de MMP-14 em cÃlulas neoplÃsicas foi frequentemente positiva em tumores primÃrios (50/50 = 100%) e metastÃticos (7/8= 88%). Em mononucleares, a maioria dos quais macrÃfagos (corados pelo CD68), a expressÃo positiva de MMP-14 tambÃm predominou marcadamente, tanto em tumores primÃrios (46/47 = 98%) como em carcinomas metastÃticos (9/10 = 90%). A expressÃo de TIMP-2 em cÃlulas neoplÃsicas, discreta, ocorreu em 70% de tumores primÃrios (35/50 casos) e 100% dos metastÃticos (8/8). A imunocoloraÃÃo para TIMP-2 em macrÃfagos associados ao tumor (TAMs) foi ainda mais elevada do que nas cÃlulas neoplÃsicas. Em conclusÃo, a MMP-14 e TIMP-2 sÃo frequentemente expressas em carcinomas colo-retais em ambas localizaÃÃes anatÃmicas, principalmente nas metÃstases para linfonodos , sugerindo que estas proteases desempenham papel importante na invasÃo local e na progressÃo tumoral neste tipo de cÃncer. A predominÃncia destes marcadores nas cÃlulas mononucleares (sobretudo macrÃfagos) , claramente evidentes na positividade para a MMP-2, enfatiza a importÃncia do microambiente tumoral no desenvolvimento de neoplasias. / The colorectal cancer (RCC) is highly prevalent in richer and industrialized countries. The matrix metalloproteinases (MMPs) are regarded as important for facilitating tumor invasion and spread in various cancers, including colorectal. Tissue inhibitors of metalloproteinases (TIMPs) are the major physiological inhibitors of MMPs. The expression of metalloproteinase-2 (MMP-2), metalloproteinase 14 (MMP-14) and tissue inhibitor of metalloproteinases-2 ( TIMP-2) in colorectal cancer was assessed. CD68 immunostaininig was utilized to the characterization of mononuclear cells nature. Paraffin-embedded tissues from patients undergoing colectomy for colorectal cancer in the period 2004 to 2010, were selected from the files of the Department of Pathology and Forensic Medicine (DPML), Medical School , Federal University of Cearà (UFC). Tissue microarrays were performed and slides were obtained for immunohistochemical detection of the expression of MMP-2, MMP-14 and TIMP-2 and the tissue samples analyzed. The following scores were applied: 0 = no immunostaining or rare labeled cells (<5%), 1 = slight marking the majority (> 50%) of tumor cells or stromal mononuclear cells, or moderate marking in a minority of cells (<50%) 2 = moderate labeling in the majority (> 50%) of tumor or mononuclear cells or intense marking in the minority of cells (<50%) and 3 = intense labeling in the majority (> 50%) of tumor cells or mononuclear cells. In this study, the relationship between increased expression of MMP-14 in mononuclear primary tumor cells and cases without lymph node metastases (MMP-14, 2 and 3/N0 scores: 23/26 = 88%; N1-N3: 14/21 = 67%, p = 0.0353) was stablished . However, no significant relationship was found between the immunohistochemical expression of MMP-14, MMP-2 and TIMP-2 in primary tumors in cancer cells and mononuclear cells and other clinico-pathological parameters. The expression of MMP-2 were negative in the neoplastic cells both in primary tumors (47/47 = 100%) and in metastatic ones (12/12 = 100%). The immunoreactivity of MMP-14 in neoplastic cells in primary tumors was positive (50/50 = 100%) and in all cases except one of metastatic carcinoma (7/8 = 88%). In mononuclear cells, most of them characterized as macrophages (CD68 stained), MMP-14 positive expression also predominated markedly, both in primary tumors (46/47 = 98%) and in metastatic carcinomas (9/10 = 90%). TIMP-2 expression in neoplastic cells of primary tumors occurred in 35/50 cases (70%) and lymph nodes showed positive immunostaining in all cases (8/8 = 100%). In both sites there were no cases with high expression. The TIMP-2 immunoreactivity in tumour associated macrophages (TAMs) was even higher than in the neoplastic cells. In conclusion, MMP-14 and TIMP-2 are frequently expressed in colorectal carcinomas in both anatomical sites , mainly in lymph node metastasis, suggesting that these proteases play an important role in local invasion and tumor progression of these cancers. The predominance of these biomarkers in mononuclear cells, clearly evident in the positivity for MMP-2, emphasizes the importance of tumor microenvironment in the development of neoplasms.

Abstract Lymphomas are a heterogeneous group of malignancies, which usually have a good prognosis and high cure rates. Lymphomas are sensitive to chemotherapy and radiotherapy, and many patients can be cured even after a relapse, resulting in a need for effective follow-up. However, the cost-benefit ratio of radiological imaging in predicting the forthcoming relapses is poor. Consequently, there is a need for biological prognostic and predictive markers to distinguish patients at the highest risk of relapse at the time of diagnosis or during follow-up. Despite rapid progress in lymphoma treatments, some patients still die from lymphoma. Thus, more data on the basic biological features of lymphomas are also needed. Gelatinases (MMP-2 and MMP-9) and their tissue inhibitors (TIMP-1 and TIMP-2) have been found to play a role in the progression of solid tumours. TP53 is a tumour suppressor gene, the mutations and protein over-expression of which have been demonstrated to be associated with survival in most cancer types. There is also some evidence that these proteins could have prognostic significance in lymphomas as well. In the present study, the tissue expression, plasma concentrations and clinical value of gelatinases and their tissue inhibitors were evaluated in lymphomas. 249 primary tissue samples from patients with Hodgkin, follicular, or diffuse large B-cell lymphoma were analysed for expression of gelatinases and/or their inhibitors using immunohistochemistry. In follicular lymphoma, p53 protein expression was also investigated. The plasma samples of 126 lymphoma patients and a control group of 44 healthy volunteers were collected and studied by ELISA. TIMP-1 expression correlated with bulky tumour and nodular sclerosis subtype of Hodgkin lymphoma. In follicular lymphoma, p53 over-expression was an independent adverse prognostic factor for survival and a predictor of histological transformation. Plasma MMP-2-TIMP-2 complex appeared to be a potential follow-up marker predicting the risk of relapse in lymphoma patients. Plasma levels of the MMP-2-TIMP-2 complex, proMMP-2, TIMP-2 and proMMP-2/TIMP-2 ratio were at abnormal levels both in patients with newly diagnosed lymphoma and those in remission compared to healthy controls. The clinical significance of these markers needs further studies.

Systemic hypoxia frequently occurs in patients with cardiopulmonary diseases. Maintenance of vascular reactivity and endothelial viability is essential to preserving oxygen delivery in these patients. The role of matrix metalloproteinase-2 (MMP-2) and heme oxygenase-2 (HO-2) in the vascular response to hypoxia were investigated. In the first part of the thesis, the role of MMP-2 in regulating systemic arterial contraction after prolonged hypoxia was investigated. MMP-2 inhibition with cyclic peptide CTTHWGFTLC (CTT) reduced phenylephrine (PE)-induced contraction in aortae and mesenteric arteries harvested from rats exposed to hypoxia for 7 d. Responses to PE were reduced in MMP-2-/- mice exposed to hypoxia for 7 d compared to wild-type controls. CTT reduced contraction induced by big endothelin-1 (big ET-1) in aortae harvested from rats exposed to hypoxia. Increased contraction to big ET-1 after hypoxia was observed in wild-type controls, but not MMP-2-/- mice. Rat aortic MMP-2 and MT1-MMP protein levels and MMP activity were increased after 7 d of hypoxia. Rat aortic MMP-2 and MT1-MMP mRNA levels were increased in the deep medial vascular smooth muscle. These results suggest that hypoxic induction of MMP-2 activity potentiates contraction in systemic conduit and resistance arteries through proteolytic activation of big ET-1. The second part of the thesis investigated oxygen regulation of HO-2 protein and whether it plays a role in preserving endothelial cell viability during hypoxia. HO-2, but not HO-1, protein level was maintained during hypoxia in human endothelial cells through enhanced translation of HO-2 transcripts. Inhibition of HO-2 expression increased the production of reactive oxygen species, decreased mitochondrial membrane potential, and enhanced apoptotic cell death and activated caspases during hypoxia, but not during normoxia. These data indicate that HO-2 is translationally regulated and important in maintaining endothelial viability and function during hypoxia. In summary, the thesis demonstrates the importance of MMP-2 and HO-2 in preserving vascular function during prolonged systemic hypoxia. These enzymatic pathways may, therefore, represent novel therapeutic targets that may be exploited to ameliorate the effects of hypoxia in patients with cardiopulmonary disease.

Three protease inhibitor-like proteins (PILPs) identified from Bungarus multicinctus genome are structurally homologous with Kunitz-type proteinase inhibitor. The goal of the present study is to explore whether PILPs exhibit an inhibitory action on matrix metalloproteinase 2 (MMP-2) activity. Unlike PILP-1 and PILP-2, PILP-3 was found to inhibit MMP-2 activity as evidenced by specific substrate assay. Moreover, in vitro migration and invasion assays, and wound-healing assay showed that PILP-3 suppressed the migration and invasion of human neuroblastoma SK-N-SH cells. Pull-down assay and dot blotting-binding assay proved an interaction between PILP-3 and MMP-2. Nevertheless, PILP-3 did not affect either expression or secretion of MMP-2 in SK-N-SH cells. In terms of highly structural similarity between PILP-2 and PILP-3, two chimeric mutants in which amino acids at N-terminus and C-terminus of PILP-3 were substituted by those of PILP-2 were prepared. In contrast to N-terminus chimera, C-terminus mutant of PILP-3 was unable to inhibit MMP-2 activity and showed a reduction in binding with MMP-2. Taken together, our data suggest that PILP-3 may be a useful template for rational designing pharmaceutical agent in inhibiting MMP-2 activity.

No description available.

No description available.

Systemic hypoxia frequently occurs in patients with cardiopulmonary diseases. Maintenance of vascular reactivity and endothelial viability is essential to preserving oxygen delivery in these patients. The role of matrix metalloproteinase-2 (MMP-2) and heme oxygenase-2 (HO-2) in the vascular response to hypoxia were investigated. In the first part of the thesis, the role of MMP-2 in regulating systemic arterial contraction after prolonged hypoxia was investigated. MMP-2 inhibition with cyclic peptide CTTHWGFTLC (CTT) reduced phenylephrine (PE)-induced contraction in aortae and mesenteric arteries harvested from rats exposed to hypoxia for 7 d. Responses to PE were reduced in MMP-2-/- mice exposed to hypoxia for 7 d compared to wild-type controls. CTT reduced contraction induced by big endothelin-1 (big ET-1) in aortae harvested from rats exposed to hypoxia. Increased contraction to big ET-1 after hypoxia was observed in wild-type controls, but not MMP-2-/- mice. Rat aortic MMP-2 and MT1-MMP protein levels and MMP activity were increased after 7 d of hypoxia. Rat aortic MMP-2 and MT1-MMP mRNA levels were increased in the deep medial vascular smooth muscle. These results suggest that hypoxic induction of MMP-2 activity potentiates contraction in systemic conduit and resistance arteries through proteolytic activation of big ET-1. The second part of the thesis investigated oxygen regulation of HO-2 protein and whether it plays a role in preserving endothelial cell viability during hypoxia. HO-2, but not HO-1, protein level was maintained during hypoxia in human endothelial cells through enhanced translation of HO-2 transcripts. Inhibition of HO-2 expression increased the production of reactive oxygen species, decreased mitochondrial membrane potential, and enhanced apoptotic cell death and activated caspases during hypoxia, but not during normoxia. These data indicate that HO-2 is translationally regulated and important in maintaining endothelial viability and function during hypoxia. In summary, the thesis demonstrates the importance of MMP-2 and HO-2 in preserving vascular function during prolonged systemic hypoxia. These enzymatic pathways may, therefore, represent novel therapeutic targets that may be exploited to ameliorate the effects of hypoxia in patients with cardiopulmonary disease.

Diss. Linköping : Linköpings universitet, 2007.

Thesis (Ph. D.)--University of Oklahoma. / Bibliography: leaves 153-217.

Orientador: Gisele Fabrino Machado / Banca: Mary Marcondes / Banca: Antonio Carlos Alessi / Resumo: A leishmaniose visceral canina, causada pelo protozoário Leishmania (Leishmania) chagasi, é uma doença de grande ocorrência principalmente na América Latina. A caracterização das lesões sistêmicas associadas à infecção pelo parasita tem sido amplamente estudada, entretanto, poucos autores elucidam a patogenia na forma nervosa. Com o objetivo de compreender melhor os mecanismos envolvidos na inflamação do sistema nervoso central de cães naturalmente infectados por L. chagasi, amostras de liquor e plexo coróide foram colhidas e submetidas à zimografia para a detecção de metaloproteinases (MMPs). Amostras do plexo coróide e liquor de cães sadios foram avaliadas como controle. Os géis de zimograma foram analisados quanto à presença e atividade proteolítica das metaloproteinases -2 e -9. Formas inativas das proteases foram detectadas no plexo coróide, sendo que o Grupo de animais positivos não diferiu do negativo. No liquor foram encontradas formas ativas e inativas das MMPs-2 e -9 e a atividade proteolítica das mesmas diferiu entre os Grupos positivo e negativo. A MMP-2 teve maior detecção nos animais negativos e a MMP-9 nos positivos. O aumento da MMP- 9 no liquor dos cães doentes representa seu possível envolvimento na patogenia das lesões encefálicas ao ocasionarem o rompimento das barreiras hematoencefálica e/ou hematoliquórica, permitindo a passagem de células e proteínas envolvidas no processo inflamatório / Abstract: Canine visceral leishmaniasis, caused by the protozoan Leishmania (Leishmania) chagasi, is a disease with high occurrence in Latin America. The characteristics of the systemic lesions related to the infection have been widely studied, but few studies clarify the disease on a neurological aspect. With the aim of a better understanding of the inflammation mechanisms within the central nervous system of dogs naturally infected by L. chagasi, some samples of cerebrospinal fluid and choroid plexus were collected and submitted to zymography to detect metalloproteinases (MMPs). Samples of choroid plexus and cerebrospinal fluid from healthy dogs were evaluated as control. The zymogram gels were analysed taking into account the presence and the proteolytic activity of metalloproteinase -2 and -9. Inactive forms of the proteases were detected in the choroid plexus, and the group of positive animals did not differ from negative ones. In the cerebrospinal fluid, active and inactive forms of MMP-2 and -9 were found, and their proteolytic activity differed between negative and positive groups. MMP-2 had higher detection in the negative animals and MMP-9 in the positive ones. The increasing of MMP-9 in the cerebrospinal fluid of infected dogs represents its possible involvement in the brain injuries, by causing the disruption of blood-cerebrospinal fluid barrier and/or blood-brain-barrier, allowing the passage of cells and proteins involved in inflammation process / Mestre