• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 11
  • 3
  • 2
  • 1
  • 1
  • Tagged with
  • 19
  • 10
  • 10
  • 8
  • 7
  • 7
  • 7
  • 6
  • 5
  • 4
  • 4
  • 4
  • 4
  • 4
  • 4
  • 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.
11

Do Serglycin Related Alterations of Thrombocytes and Myeloid Cells Affect Tumor Progression and Behavior

Hjelle, Kjersti Marie January 2015 (has links)
Investigation of tumor growth has traditionally been studied focusing only on the cancer cells. However, tumors consist of a complex tissue organization where heterotypic signaling occurs between different cell types. The cross-talk between tumor cells and other surrounding cell types may ultimately prove to be as important for the tumor cell behavior as the internal signaling cascades in the tumor cell itself.Myeloid cells, such as granulocytes and monocytes, and thrombocytes play an important role in the tumor tissue, as a tumor can be compared to a wound healing process without the normal regulation mechanisms. Platelets are thought to facilitate tumor cell extravasation by binding to the tumor cell and recruiting myeloid cells that secrete factors aiding tumor migration through the endothelial cells. Studying the content of granules and vesicles of the platelets and myeloid cells can provide important knowledge about how the tumor interactions are mediated and which key proteins that controls these processes.Serglycin is an intracellular proteoglycan that attaches chains of negatively charged glycosaminoglycans. It is thought to have a function in retaining and storing proteins in hematipoietic cells. In this project the impact of the loss of serglycin on platelets and myeloid cells was investigated, using a spontaneous insulinoma serglycin knockout mouse model. The results suggests that serglycin does not affect the amount of neutrophil granulocytes and monocytes in peripheral blood, nor does it seem to affect the amount of platelets sequestered to the tumor tissue. A co-staining for platelets and MMP9 positive granulocytes was also performed in order to assess if granulocyte-platelet interactions in the tumor were affected by loss of serglycin. Interactions between these cells were observed in both genotypes. Von Willebrand factor levels in the tumor tissue also remained unchanged upon loss of serglycin. However, preliminary experiments indicated that serglycin seems to play a role in the intracellular amounts of vimentin and VEGFB in undifferentiated primary bone marrow derived monocytes.
12

Placental vascular smooth muscle cell differentiation in pregnancies complicated by obesity and gestational diabetes

Whittle, Saxon January 2016 (has links)
The increasing demand on healthcare from pregnancies complicated by gestational diabetes (GDM) and obesity is caused in large part by fetal macrosomia (FM). Alterations to the vasculature of the placenta leading to changes to nutrient flux may be more frequent when GDM and obesity occur concomitantly. However, the impact of obesity as an independent comorbidity is poorly understood. The current study sought to characterise structural and functional changes in placenta from pregnancies complicated by GDM and/or obesity and examine the involvement of miRs in this phenomenon, as the phenotype of vascular smooth muscle (VSM) has been documented to be influenced by microRNA (miR) expression. Patients were stratified according to the presence or absence of GDM and/or obesity, which resulted in four groups. Morphometric analysis of CD31 immuno-stained placentas showed that pregnancies complicated by GDM or obesity both had a higher mean sum ratio of the area of the lumen compared to the endothelium. No relationship was found with FM. The ratio increased with maternal body mass index (BMI) in all pregnancies. Immunohistochemistry with a panel of VSM markers suggested an altered phenotype of VSM in pregnancies complicated by GDM and/or obesity. RT-QPCR and immunoblotting showed a higher expression of smooth muscle myosin (SM-MHC), h-caldesmon (HC) and alpha smooth muscle actin (ASMA) in pregnancies complicated by obesity, consistent with a greater contractile capacity. This was most marked when obesity occurred without GDM.Studies were conducted on two miRs, miR-145, which is associated with VSM in many vascular tissues, and the snoRNA-derived species miR-664a-3p, which microarray studies had shown to be higher in placentas from pregnancies complicated by GDM. Dicer and dyskerin, components of the snoRNA-derived miR biogenesis pathway, were increased and reduced respectively in GDM placenta. However, studies in cultured placental villous explants suggested that neither miR species was regulated by glucose, insulin or IGF-I. Placental mesenchymal cells are the developmental precursors of VSM. In primary culture, these cells expressed both miRs. To determine the function of miR-664a-3p, a nucleofection protocol was developed in a fetal mesenchymal cell line, WI38, and applied to first-trimester placental mesenchymal cells. Preliminary proteomic analysis after nucleofection-mediated knockdown of miR-664a-3p suggested a series of novel candidate target proteins for this uncharacterised miR species. Blood vessel structure and VSM phenotype are both altered in pregnancies complicated by GDM and/or obesity. The significance of apparently higher level of contractile proteins with wider vessel lumens in obesity requires further investigation. Translational regulation by miRs including miR-145 and miR-664a-3p is implicated in these alterations. In future, targeted therapies that alter miR levels in the placenta may be useful in control of fetal overgrowth such as FM.
13

Význam antiangiogenní terapie u lymfomu z plášťových buněk / The Role of Antiangiogenic Therapy in Mantle Cell Lymphoma

Kovaříková, Petra January 2022 (has links)
Mantle cell lymphoma (MCL) is a subtype of B-non-Hodgkin's lymphoma, characterized by often relapses. Despite an Ibrutinib (a Bruton's kinase inhibitor) implementation into salvage therapy, these patients often relapse with biologically highly aggressive disease and very poor prognosis. An increased activation of alternative metabolic pathways was described as one of ibrutinib-resistance mechanisms. Some of these pathways have also significant proangiogenic activity (e.g. PI3K-AKT-mTOR). In presented study, we established and standardized a real-time ultrasound and photoacoustic imaging of neovascularization and tissue oxygenation of subcutaneous MCL tumors in mice. Ultrasound and photoacoustic imaging is a fast, non-invasive method for angiogenesis evaluation in subcutaneous tumors with huge preclinical potential. Using MCL mice models, we also demonstrated the importance of CD31/PECAM-1 expression for engraftment, growth and spread of MCL cells in vivo. The level of CD31 expression in primary MCL cell (obtained directly from MCL patients) positively correlates with extent of extranodal involvement. CD31 facilitates survival and regulates extranodal spread of mantle cell lymphoma. We found that increased VEGFA expression causes not only increased microvessel density due to higher sprouting...
14

Avaliação imunohistoquímica da densidade microvascular em adenocarcinoma gástrico / Immunohistochemistry avaliation of microvascular density in gastric adenocarcinoma

Marinho, Eneida Ribeiro 13 October 2003 (has links)
O crescimento e a progressão tumorais estão associados à indução da angiogênese. O objetivo deste estudo foi avaliar a imunoexpressão do VEGF e a densidade de microvasos em adenocarcinomas gástricos. Espécimes cirúrgicos de 89 pacientes submetidos à ressecção gástrica com dissecção linfonodal a D2 foram analisados quanto à densidade microvascular tumoral. Testes imunohistoquímicos foram realizados utilizando-se os anticorpos CD31, CD34, Fator VIII e VEGF através do método da streptavidina-biotina. Os vasos foram contados nas áreas de maior vascularização tumoral e o VEGF foi graduado de 0 a 3, de acordo com a intensidade da imunocoloração. Os resultados imunohistoquímicos foram comparados com os dados patológicos e de extensão loco-regional da doença. Sessenta pacientes (67,4%) eram do sexo masculino e a média de idade foi 59,9 (±13,8) anos. Os tumores foram classificados em tipo intestinal em 62 casos (69,7%) e em difuso em 27 (30%). Onze pacientes (12,4%) apresentaram tumores precoces. A densidade microvascular apresentou média de 67,8 (±31,5) para o anticorpo CD31 e 94,2 (±39,0) para o CD34. A média do número de vasos corados pelo Fator VIII foi 9,2 (±8,2). Houve uma correlação entre os resultados imunohistoquímicos para CD31 e CD34, com r=0,57 e p=0,01. Segundo o VEGF os tumores foram: grau 0 = 16 (18%), I = 48 (53,9%), II = 16 (18%) e III = 9 (10,1%). Não houve associação entre a DMV e os dados patológicos: tipo histológico, grau de diferenciação, tamanho do tumor, invasão da parede gástrica, metástases linfonodais e metástase à distância. A imunoexpressão do VEGF foi associada com alta DMV (p=0,03) e com o estádio tumoral - TNM (p=0,003). Os resultados deste estudo permitiram concluir que a coloração imunohistoquímica com o Fator VIII não é segura como um marcador de células endoteliais; que os anticorpos CD31 e CD34 foram úteis na avaliação da DMV; e que a imunoexpressão do VEGF pode identificar um comportamento biológico mais agressivo / Tumor growth and progression, particularly in aggressive and malignant tumors, are associated with the induction of angiogenesis. The aim of this study was to evaluate the role of VEGF immunoexpression and microvascular density in gastric adenocarcinomas. Specimens from eightynine patients who underwent gastric resection with DII lymph node dissection were analyzed regarding microvascular density of the tumors. Immunohistochemistry for CD31, CD34, Factor VIII and VEGF were performed using the streptavidin-biotin-method. The vessels were counted in a hot spot area of the tumors and VEGF was categorized as grade 0 to III, according to the intensity. Immunohistochemical results were compared to pathological data and loco-regional extension of the disease. In the results of 89 patients, sixty (67.4%) were men, and the mean age was 59.9 ± 13.8 years. The tumors were classified as intestinal type in 62 (69.7%) and diffuse in 27 (30.3%). Eleven (12.4%) were early gastric tumors. Microvascular density showed a mean of 67.8 (± 31.5) for CD31 and 94.2 (± 39) for CD34 vessels. The mean number of vessels revealed by the antibody Fator VIII was 9.2 (± 8.2). There was a correlation between immunohistochemistry for CD31 and CD34, r = 0.57, p < 0.01. The tumors were classified for VEGF as: grade 0 = 16 (18%); I = 48 (53,9%); II = 16 (18%) and III = 9 (10,1%). There was no association between immunohistochemistry and pathological data including: histologic type, grade of differentiation, tumor size, tumor depth, lymph node metastasis and distant metastasis. However, VEGF immunoexpression was associated with high microvascular density (p = 0,03) and there was an association between the immunoexpression of VEGF and the tumor stage - TNM (p = 0,003). It was concluded that immunohistochemical staining for anti-Factor VIII was not reliable as a microvascular density marker; CD31 and CD34 were useful to demonstrate microvascular density and VEGF immunoexpression may identify tumors with more aggressive biological behavior
15

Avaliação imunohistoquímica da densidade microvascular em adenocarcinoma gástrico / Immunohistochemistry avaliation of microvascular density in gastric adenocarcinoma

Eneida Ribeiro Marinho 13 October 2003 (has links)
O crescimento e a progressão tumorais estão associados à indução da angiogênese. O objetivo deste estudo foi avaliar a imunoexpressão do VEGF e a densidade de microvasos em adenocarcinomas gástricos. Espécimes cirúrgicos de 89 pacientes submetidos à ressecção gástrica com dissecção linfonodal a D2 foram analisados quanto à densidade microvascular tumoral. Testes imunohistoquímicos foram realizados utilizando-se os anticorpos CD31, CD34, Fator VIII e VEGF através do método da streptavidina-biotina. Os vasos foram contados nas áreas de maior vascularização tumoral e o VEGF foi graduado de 0 a 3, de acordo com a intensidade da imunocoloração. Os resultados imunohistoquímicos foram comparados com os dados patológicos e de extensão loco-regional da doença. Sessenta pacientes (67,4%) eram do sexo masculino e a média de idade foi 59,9 (±13,8) anos. Os tumores foram classificados em tipo intestinal em 62 casos (69,7%) e em difuso em 27 (30%). Onze pacientes (12,4%) apresentaram tumores precoces. A densidade microvascular apresentou média de 67,8 (±31,5) para o anticorpo CD31 e 94,2 (±39,0) para o CD34. A média do número de vasos corados pelo Fator VIII foi 9,2 (±8,2). Houve uma correlação entre os resultados imunohistoquímicos para CD31 e CD34, com r=0,57 e p=0,01. Segundo o VEGF os tumores foram: grau 0 = 16 (18%), I = 48 (53,9%), II = 16 (18%) e III = 9 (10,1%). Não houve associação entre a DMV e os dados patológicos: tipo histológico, grau de diferenciação, tamanho do tumor, invasão da parede gástrica, metástases linfonodais e metástase à distância. A imunoexpressão do VEGF foi associada com alta DMV (p=0,03) e com o estádio tumoral - TNM (p=0,003). Os resultados deste estudo permitiram concluir que a coloração imunohistoquímica com o Fator VIII não é segura como um marcador de células endoteliais; que os anticorpos CD31 e CD34 foram úteis na avaliação da DMV; e que a imunoexpressão do VEGF pode identificar um comportamento biológico mais agressivo / Tumor growth and progression, particularly in aggressive and malignant tumors, are associated with the induction of angiogenesis. The aim of this study was to evaluate the role of VEGF immunoexpression and microvascular density in gastric adenocarcinomas. Specimens from eightynine patients who underwent gastric resection with DII lymph node dissection were analyzed regarding microvascular density of the tumors. Immunohistochemistry for CD31, CD34, Factor VIII and VEGF were performed using the streptavidin-biotin-method. The vessels were counted in a hot spot area of the tumors and VEGF was categorized as grade 0 to III, according to the intensity. Immunohistochemical results were compared to pathological data and loco-regional extension of the disease. In the results of 89 patients, sixty (67.4%) were men, and the mean age was 59.9 ± 13.8 years. The tumors were classified as intestinal type in 62 (69.7%) and diffuse in 27 (30.3%). Eleven (12.4%) were early gastric tumors. Microvascular density showed a mean of 67.8 (± 31.5) for CD31 and 94.2 (± 39) for CD34 vessels. The mean number of vessels revealed by the antibody Fator VIII was 9.2 (± 8.2). There was a correlation between immunohistochemistry for CD31 and CD34, r = 0.57, p < 0.01. The tumors were classified for VEGF as: grade 0 = 16 (18%); I = 48 (53,9%); II = 16 (18%) and III = 9 (10,1%). There was no association between immunohistochemistry and pathological data including: histologic type, grade of differentiation, tumor size, tumor depth, lymph node metastasis and distant metastasis. However, VEGF immunoexpression was associated with high microvascular density (p = 0,03) and there was an association between the immunoexpression of VEGF and the tumor stage - TNM (p = 0,003). It was concluded that immunohistochemical staining for anti-Factor VIII was not reliable as a microvascular density marker; CD31 and CD34 were useful to demonstrate microvascular density and VEGF immunoexpression may identify tumors with more aggressive biological behavior
16

Angiogênese em neoplasias epiteliais corticais renais: estudo de 41 casos

Suzigan, Sueli 03 May 2002 (has links)
Made available in DSpace on 2016-01-26T12:51:19Z (GMT). No. of bitstreams: 1 suelisuzigan_tese_parte5.pdf: 78044 bytes, checksum: ede6079670fe7d13ddd7e25ead03f505 (MD5) Previous issue date: 2002-05-03 / Introduction. Tumor growth and metastasis depend greatly on angiogenesis. There are several angiogenic growth factors able to induce new vessels in renal tumors, but the most important are vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (b-FGF). The aim of our study was to investigate expression of b-FGF and to quantify microvessel density (MVD) in oncocytomas and renal cell carcinomas (RCCs) and to relate these parameters of tumor vascularity to other clinicopathological features. Material and Methods. b-FGF and CD31 immunostaining were performed on formalin-fixed paraffin-embedded archival tissues from Larpac Laboratories files, including 36 RCCs (10 conventional, 10 papillary, 8 sarcomatoid, and 8 chromophobe) and 5 oncocytomas. Angiogenesis was quantified microscopically by two independent observers. Results. b-FGF was positive in all five oncocytomas and only in seven of 36 RCCs: 5 of conventional type, 1 papillary, and 1 chromophobe. All sarcomatoid carcinomas were negative. The expression of b-FGF was not related to tumor size, grade, stage, or short survival in either group. MVD mean value was 124.16 ± 50.1 in oncocytomas and 91.54 ± 52.4 in RCCs. The pattern of vascularization observed in oncocytomas was characterized by a fine vascular network around groups of tumor cells although in RCCs the microvessels tended to be more disorganized. When analyzing only carcinomas, patients who died within 12 months after the diagnosis had a tumoral MVD mean value significantly higher (124.12 ± 75.2) than that observed in patients who were still alive one year after diagnosis (80.34 ± 37.8). ix Conclusion. We demonstrate that b-FGF is expressed more often in oncocytomas than in RCCs but MVD is similar in both groups of tumors. The high expression of b-FGF in oncocytomas may reflect the peculiar pattern of vascularization of these tumors. High MVD in rapidly lethal RCCs is an indication that angiogenesis may be correlated with the degree of malignancy of these tumors. / O desenvolvimento dos tumores e das suas metastases dependem em grande parte da angiogenese tumoral. Existem varios fatores de crescimento capazes de induzir à neoformação vascular nas neoplasias renais, porém, os mais importantes são o fator de crescimento do entotélio vascular (vegf) e o fator de crescimento fibroblástico básico (bfgf). O objetivo deste estudo foi o de investigar a expressão do b-fgf e a densidade microvascular (dmv) nos oncocitomas e nos carcinomas de células renais (ccrs) e correlacionar estes parâmetros da vascularização tumoral com outros ascpectos clínico-patológicos. Material e métodos. O estudo imunohidtoquímico para o b-fgf e o cd31 (densidade microvascular) foi realizado em material fixado em formalina e incluído em parafina de 36 casos de ccrs (10 convencionais, 10 papilíferos, 8 sarcomatóides e 8 cromófobos) e 5 oncocitomas, oriundos de exames anátomo-patológicos por dois observadpres independentes. Resultados. Nota de Resumo Foi encontrada positividade para o b-fgf em todos os 5 casos de oncocitomas e em 7 dos 36 casos de ccrs: 5 do tipo convencional, um papilífero, e um cromófobo. Todos os carcinomas sarcomatóides mostraram-se negativos. A expressão tumoral do b-fgf não apresentou correlação com tamanho tumora, grau histológico, estadio patológico, ou sobrevida a curto prazo em nenhum dos grupos. O valor médio da dvm foi de 124,16 +/- 50,1 nos oncocitomas e de 91,54 +/- 52,4 nos ccrs. O padrão de vascularização observado nos oncocitomas era caracterizado por um delicado leito vascular envolvendo grupos de celulas tumorais, enquanto que nos ccrs a microvascularização se apresentou de forma mais organizada. Entre os carcinomas, os tumores que se mostraram letais nos 12 primeiros meses após o diagnóstico, apresentaram um ídice angiogênico significativamente maior (124,12 +/- 75,2) em relação aos pacientes que ainda permaneciam vivos um ano após o diagnóstico (80,34 +/- 37,8). Conclusão. Demostramos que o b-fgf está expresso mais freqüentemente nos oncocitomas do que nos ccrs. Nota de Resumo Apesar de as dmv ser semelhante em ambos os grupos tumorais, observou-se um padrão de vascularização característico nos oncocitomas. Uma dvm mais elevada nos ccrs, rapidamente letais é indicativo de que a angiogenese possa estar correlacionada com grau de malignidade destes tumores.
17

CD31(-) HipOps - A Highly Osteogenic Cell Population From Mouse Bone Marrow

McKenzie, Kristen Penny 04 December 2012 (has links)
Multipotent mesenchymal stem cells (MSCs), found in many adult tissues, may be useful for regenerative medicine applications. Their identification and purification have been difficult due to their low frequency and lack of unambiguous markers. Using a magnetic micro-beads negative selection technique to remove contaminating hematopoietic cells from mouse bone marrow stromal cells (BMSCs), our lab recently isolated a highly purified osteoprogenitor (HipOp) population that was also enriched for other mesenchymal precursors, including MSCs (Itoh and Aubin, 2009). To further enhance enrichment, we positively selected BMSCs and HipOps for CD73, a putative MSC marker, which resulted in no significant additional enrichment for osteoprogenitors when the population was tested in vitro. However, we also found that HipOps were enriched in vascular endothelial cells, and that removing these cells by further negative selection with CD31/PECAM resulted in a CD31(-) HipOp population with higher osteogenic capacity than HipOps in vitro and in vivo.
18

CD31(-) HipOps - A Highly Osteogenic Cell Population From Mouse Bone Marrow

McKenzie, Kristen Penny 04 December 2012 (has links)
Multipotent mesenchymal stem cells (MSCs), found in many adult tissues, may be useful for regenerative medicine applications. Their identification and purification have been difficult due to their low frequency and lack of unambiguous markers. Using a magnetic micro-beads negative selection technique to remove contaminating hematopoietic cells from mouse bone marrow stromal cells (BMSCs), our lab recently isolated a highly purified osteoprogenitor (HipOp) population that was also enriched for other mesenchymal precursors, including MSCs (Itoh and Aubin, 2009). To further enhance enrichment, we positively selected BMSCs and HipOps for CD73, a putative MSC marker, which resulted in no significant additional enrichment for osteoprogenitors when the population was tested in vitro. However, we also found that HipOps were enriched in vascular endothelial cells, and that removing these cells by further negative selection with CD31/PECAM resulted in a CD31(-) HipOp population with higher osteogenic capacity than HipOps in vitro and in vivo.
19

Μελέτη της έκφρασης των υποδοχέων των νευροτροφινών σε αδενώματα υπόφυσης στον άνθρωπο

Χονδρογιάννη, Χριστίνα 16 February 2009 (has links)
Οι νευροτροφίνες (ΝΤs), Nerve Growth Factor (NGF), Brain-Derived Neurotrophin Factor (BDNF), NΤ-3, ΝΤ-4, ΝΤ-5 και ΝΤ-6 ανήκουν σε μια οικογένεια πολυπεπτιδικών αυξητικών παραγόντων οι οποίοι απαιτούνται για την ανάπτυξη του νευρικού συστήματος στα σπονδυλωτά. Εμπλέκονται στην επιβίωση, στη διαφοροποίηση, στην ωρίμανση των νευρώνων, στη συναπτική πλαστικότητα, στη μάθηση, στη μνήμη, καθώς επίσης και στην έκφραση και ενεργότητα σημαντικών πρωτεϊνών, όπως ιοντικών καναλιών και νευροδιαβιβαστικών υποδοχέων. Οι λειτουργίες αυτές επιτελούνται μέσω της δέσμευσής τους σε δύο είδη μεμβρανικών υποδοχέων, της οικογένειας κινάσης-τυροσίνης TrkA, TrkB και TrkC (tropomyosinerelated kinase) και του pan-neurotrophin (με ικανότητα δέσμευσης με όλες τις νευροτροφίνες) υποδοχέα p75NTR που είναι μέλος των υποδοχέων Tumor Necrosis Factors (TNFs). Οι νευροτροφίνες εκφράζονται σε κύτταρα του Κ.Ν.Σ. και Π.Ν.Σ. αλλά και σε ιστούς-όργανα εκτός νευρικού συστήματος, όπως είναι η υπόφυση. Σκοπός της εργασίας ήταν να μελετήσουμε την έκφραση των υποδοχέων των νευροτροφινών με σύγχρονες μεθόδους ανοσοϊστοχημείας σε αδενώματα της υπόφυσης και να συσχετίσουμε την έκφρασή τους με τα κλινοκοπαθολογικά χαρακτηριστικά των ασθενών. Όλα τα αδενώματα της μελέτης που συμπεριλήφθησαν στη μελέτη (10ανδρών και 8 γυναικών) εμφάνισαν ανοσοϊστοχημική χρώση για τον υποδοχέα TrkA και συγκεκριμένα έντονη χρώση (+3) τα 9/18 (50%) των περιστατικών, μέτρια χρώση (+2) τα 8/18 (45%) των περιστατικών και ασθενή χρώση (+1) 1/18 (5%) των περιστατικών. Ο υποδοχέας TrkB εμφάνισε θετικότητα στο 83% (15/18) των περιπτώσεων. Τα 6/15 (40%) περιστατικά παρουσίασαν έντονη χρώση (+3), τα 4/15 (27%) περιστατικά μέτρια χρώση (+2) και τα 5/15 (33%) περιστατικά ασθενή χρώση (+1). Ανοσοϊστοχημική χρώση για τον υποδοχέα TrkB παρατηρήθηκε επίσης στα αγγεία 4/15 (27%) των αδενωμάτων. Τα 11/18 (61%) των αδενωμάτων παρουσίασαν ανοσοθετικότητα για τον TrkC και συγκεκριμένα τα 3/11 (27%) περιστατικά εμφάνισαν μέτρια χρώση (+2) και 8/11 (73%) περιστατικά ασθενή (+1). Χρώση για τον υποδοχέα TrkC εντοπίστηκε σε αγγεία σε 4/11 περιστατικά (36%). Τέλος έκφραση για τον p75 υποδοχέα δεν παρατηρήθηκε σε κανένα αδένωμα. Με δεδομένο ότι οι υποδοχείς TrkB και TrkC εκφράζονται στα αγγεία των αδενωμάτων, μελετήθηκε η έκφραση των υποδοχέων των νευροτροφινών σε σχέση με την αγγειογένεση, ένας μηχανισμός που αφορά άμεσα την πρόγνωση και την ανταπόκριση στην αντίστοιχη θεραπεία των όγκων. Μελετήθηκε η έκφραση του CD31(platelet endothelial cell adhesion molecule) και του VEGFR3 (Vascular Endothelial Growth Factor Receptor 3). Ο παράγοντας VEGFR3 συμβάλλει επίσης και στην ανάπτυξη λεμφαγγείων στο στρώμα του όγκου επάγοντας την ανάπτυξή του. Η εκτίμηση της ανοσοεντόπισης για τον CD31 και τον VEGFR3 για κάθε νεόπλασμα έγινε κατόπιν επιλογής τριών αγγειοβριθέστερων περιοχών, την καταμέτρηση των αγγείων σε κάθε περιοχή και τον υπολογισμό του μέσου όρου (MCV Microvessel Count). Για τον παράγοντα VEGFR3 το 89% των περιστατικών ήταν θετικά εμφανίζοντας ένα εύρος MCV της τάξης των 2 έως 32,67, ενώ για τον παράγοντα CD31 το 100% των αδενωμάτων ήταν θετικά με MCV της τάξης των 4,67 έως 53,67. Δεν παρατηρήθηκε συσχέτιση του MCV με την έκφραση των υποδοχέων των νευροτροφινών. Οι υποδοχείς των νευροτροφινών ενώ εκφράζονται στη φυσιολογική υπόφυση συμμετέχοντας στην ανάπτυξη και στην επιβίωση των κυττάρων, δεν «σιωπούν» στα αδενώματά της. Το ερώτημα που γεννάται είναι αν δρουν ως παράγοντες διατήρησης της καλοήθειας ή αν συμβάλλουν στην ογκογένεση και στην μετέπειτα εξέλιξη των νεοπλασμάτων της υπόφυσης. Περαιτέρω μελέτες απαιτούνται για την διερεύνηση του ρόλου των νευροτροφινών μέσω των υποδοχέων τους στα αδενώματα υπόφυσης, στον άνθρωπο. / -

Page generated in 0.0358 seconds