As neoplasias tireoidianas são importante causa de morbi-mortalidade. A patogênese da disseminação neoplásica pelo organismo é um complexo e intrigante processo pelo qual grande parte das neoplasias malignas se dissemina, a partir de um sítio de origem, para diferentes partes do organismo, utilizando como vias preferenciais os sistemas vasculares venoso e linfático. A expressão dos fatores de crescimento endotelial vascular e de seus receptores (VEGFs e VEGFRs) estão relacionados à angiogênese e linfangiogênese tumoral participando do diagnóstico, avaliação prognostica e tratamento de neoplasias malignas. O papel da angiogênese e da linfangiogênese na patogênese dos cânceres de tireóide ainda não foi completamente desvendado. Os diferentes padrões de comportamento dos tumores tireoidianos e de suas metástases variam de acordo com o tipo de tumor e ainda não foi completamente explorado se diferenças na expressão dos VEGFs e VEGFRs influenciam a metástase tumoral ou determinam um comportamento mais agressivo. Na presente tese, avaliamos a expressão imuno-histoquímica dos VEGFs e VEGFRs e a densidade vascular sanguínea e linfática nos bócios adenomatosos, tireoidites linfocitárias e adenomas foliculares, bem como nos carcinomas papilíferos e foliculares e suas regiões adjacentes. Posteriormente, correlacionamos nossos achados com os dados clínico-patológicos. Observamos que há um crescimento gradual na intensidade da expressão dos VEGFs e VEGFRs a partir do tecido tireoidiano com fenótipo normal, lesões proliferativas benignas e neoplasias malignas. Nos carcinomas, apesar da profusa expressão dos VEGFs e VEGFRs detectamos correlação estatisticamente significativa apenas do VEGF-D e VEGF-R3 com um pior estadiamento tumoral nos carcinomas papilíferos. A densidade vascular sanguínea foi superior a densidade vascular linfática em todas as lesões estudadas sendo que os carcinomas foliculares apresentaram a maior densidade vascular sanguínea e as tireoidites linfocitárias a maior densidade vascular linfática. Nos carcinomas papilíferos uma menor densidade vascular sanguínea está associada a invasão vascular e a diferença de perfil linfangiogênico entre adenomas foliculares e carcinomas foliculares pode ser uma nova ferramenta na diferenciação destas categorias diagnósticas / The thyroid neoplasms are important causes of morbi-mortality. The pathogenesis of the neoplastic dissemination through the organism is a complex and intriguing process by which many malignancies spreads from a site of origin to different parts of the body, using as preferential routes the venous and lymphatic vascular systems. The expression of vascular endothelial growth factors and their receptors (VEGFs and VEGFRs) are related to tumor angiogenesis and lymphangiogenesis participating in the diagnosis, prognostic evaluation and treatment of malignant neoplasms. The role of angiogenesis and lymphangiogenesis in the pathogenesis of thyroid cancers has not been completely elucidated. The different patterns of behavior of thyroid tumors and their metastases vary with the tumoral type and have not yet been fully explored whether differences in the expression of VEGFs and VEGFRs influence tumor metastasis or determine a more aggressive behavior. In this thesis, we evaluated the immunohistochemical expression of VEGFs and VEGFRs and the blood and lymphatic vascular density in goiter, thyroiditis and follicular adenomas and in papillary and follicular carcinomas and their adjacent regions. Afterward, we correlated our findings with the clinical pathological data. We observe that there is a gradual increase in intensity of expression of VEGFs and VEGFRs from normal thyroid tissue, proliferative lesions, benign and malignant neoplasms. In carcinomas, despite the profuse expression of VEGFs and VEGFRs we detected only statistically significant correlation of VEGF-D and VEGF-R3 with a worse tumor staging in papillary carcinomas. The blood vessel density was higher than lymphatic vascular density in all lesions studied. The follicular carcinomas showed the highest blood vessel density and thyroiditis the largest lymphatic vascular density. In the papillary carcinomas a lower blood vessel density was associated with vascular invasion and the different lymphangiogenic profiles between follicular adenomas and follicular carcinomas may be a new tool in differentiating these diagnostic categories

A irradiação laser em baixa intensidade (LLLT) pode promover acelerada epitelização, maior grau de vascularização e aumento da síntese de colágeno nas feridas cirúrgicas. Porém, poucas são as evidências demonstrando que a LLLT influencie diretamente na expressão do fator de crescimento endotelial vascular (VEGF). Este estudo investigou e correlacionou a cinética de expressão de RNAm para VEGF-A165 durante o processo de reparo tecidual de feridas em língua de ratos, irradiadas (grupo GIII) ou não irradiadas (grupo GII) com o laser diodo GaAlAs. Foram realizadas pesagens sistemáticas (dias 0, 1, 2, 4 e 6) para estudar os padrões de crescimento e desenvolvimento dos animais. Animais não operados (grupo controle, GI) foram utilizados para posteriores comparações estatísticas dos valores de variação de peso (análise de variância a um critério, teste de Tukey, p<0,05). Após a cirurgia (dia 0), duas sessões de irradiação laser foram realizadas, uma logo após o procedimento operatório (laser infravermelho, 35 J/cm2) e a segunda, 48h após o início do experimento (laser vermelho visível, 5 J/cm2). Os animais foram sacrificados 1, 3, 5 e 7 dias após a cirurgia, para obtenção de amostras de tecido lingual através de biópsia. O RNA total foi extraído pela utilização do método guanidino-isotiocianato-fenol-clorofórmio. Após a transcrição reversa ? reação em cadeia da polimerase (RT-PCR), os resultados da eletroforese horizontal permitiram avaliar a razão da expressão de RNAm para GAPDH e VEGF-A165 nos grupos GI, GII e GIII (análise de variância a dois critérios, teste de Tukey, p<0,05). A média de variação de peso dos animais do grupo GII foi ao mesmo tempo maior que a do grupo GIII e menor que a do grupo GI em todos os dias de análise, observando-se diferença estatisticamente significativa (p<0,05). Apenas durante o sexto dia, não foram observadas diferenças significativas entre as médias de variação de peso dos grupos GII e GIII (p=0,220) e GI e GII (p=0,409). Os valores da expressão de RNAm para VEGF-A165 no grupo GII foram estatisticamente maiores que os do grupo GI (p=0,0285) e GIII (p=0,0101) no primeiro dia de análise. Não foram observadas diferenças estatisticamente significativas entre os grupos GI, GII e GIII quando comparados nos demais períodos de tempo. Portanto, o laser diodo GaAlAs foi capaz de biomodular a expressão do RNAm para VEGF-A165 durante o primeiro dia do processo de reparo tecidual de feridas em língua de ratos. / Low level laser therapy (LLLT) can promote accelerated epithelization, greater of vascularization and increase of collagen synthesis in surgical wounds. However, few evidences proved that LLLT directly influence in the expression of vascular endothelial growth factor (VEGF). This study investigated and correlated the kinetic of expression of mRNA VEGF-A165 during the tissue repair of wounds in tongues of irradiated (group GIII) or not irradiated rats (group GII) with GaAlAs diode laser. Systematic weighings were performed on days 0, 1, 2, 4 and 6 to study the growth and development standards of the rats, using not operated animals (control group, GI) for future statistical comparisons (one-way ANOVA and Tukey\'s test, p<0.05). Two sessions of laser irradiation were accomplished, the first one right after the surgical procedure (infrared laser, 35 J/cm2) and the second one, 48h after of the beginning of the experiment (visible red laser, 5 J/cm2). The animals were sacrificed on days 1, 3, 5 and 7 and samples of tongue tissue were obtained. The total RNA was extracted by using of guanidine-isotiocianate-phenol-chloroform method. After the reverse transcription - polymerase chain reaction (RT-PCR), the results of horizontal electrophoresis permitted to assess the ratio of mRNA GAPDH and VEGF-A165 expression for groups GI, GII and GIII (two-way ANOVA, Tukey\'s test, p<0.05). The weight variation of animals of group GII was both greater than that of animals of group GIII and lower of than that of animals of group GI in daily analysis, observing statistically significant differences (p<0.05). Only during the sixth day, significant differences between the averages of weight variation of the groups GII and GIII (p=0.220) and GI and GII (p=0.409) were not observed. The expression of mRNA VEGF-A165 in group GII was statistically greater than that of group GI (p=0.0285) and GIII (p=0.0101) in the first day. Significant differences among the groups GI, GII and GIII were not observed in other time periods. Therefore, GaAlAs diode laser was able to modulate the expression of mRNA VEGF-A165 during the first day of tissue repair process of wounds in rat tongues.

A revascularização linfática é um desafio e o estabelecimento de novas estratégias terapêuticas podem melhorar a qualidade de vida de pessoas que sofrem de distúrbios linfáticos. O objetivo deste estudo foi verificar a capacidade de tratamento com VEGFC exógeno na melhoria da vascularização linfática de uma maneira dependente do tempo em membros pélvicos (MP) de camundongos após a remoção do linfonodo inguinal. O linfonodo inguinal esquerdo foi removido cirurgicamente para mimetizar patologias com diminuição da vascularização linfática. Densidade vascular linfática (Vv) e de comprimento (Lv) foram avaliadas por imunohistoquímica, seguidas de estereologia, após a cirurgia com ou sem o tratamento com VEGFC exógeno. O grupo controle não foi manipulado, mas recebeu soro fisiológico em vez de tratamento com VEGFC exógeno. As expressões do VEGFC e FLT4 local foram avaliadas por qPCR. Houve efeito do tempo sobre Vv e Lv no Grupo Cirurgia e diferença significativa entre os grupos Controle e Cirurgia nas três regiões estudadas (região proximal, média e distal) do MP esquerdo (MPE). A Lv mostrou diferença significativa entre os grupos Controle e Cirurgia somente na região média do MPE. A Vv e a Lv para o Grupo Tratamento foram maiores do que os outros grupos em todas as regiões do MPE. A expressão gênica do VEGFC e do FLT4 apresentou efeito do tempo em todas as regiões do MPE para os grupos Cirurgia e Tratamento. Ambas as expressões gênicas do VEGFC e do FLT4 apresentaram diferença significativa entre os grupos Controle e Cirurgia, entre os grupos Cirurgia e Tratamento e entre os grupos Controle e Tratamento. Os resultados mostraram que os camundongos são bons modelos experimentais para o uso de VEGFC exógeno como terapia de revascularização linfática, e o tratamento com VEGFC exógeno aumenta vascularização linfática já após 3 dias de dano linfático. / Lymphatic revascularization is a challenge and the establishment of new therapeutic strategies may improve quality of life from those suffering from lymphatic disorders. The objective of this study was to verify the VEGFC treatment capacity in improving lymphatic vascularization in a time-dependent manner in mouse hind limb (HL) after removal of inguinal lymphnode. The left inguinal lymphnode was surgically removed to mimetize pathologies with decreased lymphatic vascularization. Lymphatic vascular density (Vv) and length (Lv) were evaluated by immunohistochemistry followed by stereology after surgery and/or VEGFC treatment. Control group was not manipulated but received saline instead of VEGFC treatment. VEGFC and FLT4 local expression were assessed by qPCR. There was effect of time over Vv and Lv in the SG and significant difference between CG and SG in the three studied regions (proximal, medium and distal region) of the left HL (LHL). The Lv showed significant difference between CG and SG only in the medium region. The Vv and the Lv for TG were higher than the other groups in all regions of LHL. VEGFC and FLT4 gene expression presented time effect in all regions of the LHL for SG and TG. Both VEGFC and FLT4 gene expression presented significant difference between CG and SG, between SG and TG, and between CG and TG. The results show that mice are good experimental models for VEGFC use as therapy for lymphatic revascularization, and VEGFC treatment increased the lymphatic vasculature already after 3 days of lymphatic damage.

Angiogenesis, the process of new vessel formation, appears to be a central mechanism that underlies the development of haemangiomas. Recently, intralesional bleomycin injection was used to treat paediatric haemangiomas with very good results. The purpose of this study was to determine whether there was significant systemic circulatory spill-over of bleomycin in haemangioma patients treated with intralesional bleomycin to determine safety of use. Furthermore, in order to elucidate bleomycin’s mechanism of action in inducing haemangioma regression, this study aimed at determining the effects of bleomycin on aspects of angiogenesis, namely, endothelial cell migration, growth and apoptosis, and comparing these effects with those of drugs previously reported to inhibit various aspects of the angiogenic process (mitomycin C, 2-methoxyestradiol, taxol, vincristine, vinblastine, colchicine, nocodazole and cytochalasin D). Lastly, the effects of bleomycin, mitomycin C, 2-methoxyestradiol, taxol, vincristine, vinblastine, colchicine, nocodazole and cytochalasin D were studied in an animal haemangioma model. A rapid and highly sensitive high performance liquid chromatographic (HPLC) method was developed. Blood samples were collected from four haemangioma patients before and after (over a 24 hour period) intralesional bleomycin (IB) therapy. As a control, blood samples were also collected at identical time intervals from four patients undergoing intravenous (IV) bleomycin chemotherapy for various malignant tumours. The HPLC method was used to quantitate bleomycin fractions in patient samples. The mean bleomycin concentration detected in plasma samples obtained from IB treated patients was 0.00 ìg/ml for both bleomycin A<Sub>2 and B2 over the 24-hour period following therapy. Plasma bleomycin A2 and B2 levels of 360.79 and 158.85 ìg/ml respectively were detected in samples obtained from cancer patients treated with bleomycin IV. These findings indicate that the low levels detected may translate to a significantly lesser risk of pulmonary fibrosis following IBI. The effect of drugs on endothelial cell migration was analyzed by wounding a confluent monolayer of cells and determining the number of cells that had migrated from the wound edge. Endothelial cell growth was determined in cells treated with various drug concentrations while apoptosis was examined using hematoxylin and eosin staining, DNA fragmentation assay and acridine orange staining. The effect of test drugs on in vitro angiogenesis was determined on endothelial cells induced to form capillary-like tubes in collagen gel. Test drugs were then evaluated for antitumour activity in an animal haemangioma model. Data demonstrated that test drugs inhibited endothelial cell migration, with the exception of mitomycin C. All test drugs induced a reduction in the percentage of viable endothelial cell in a dose-dependant manner, and also induced endothelial cell apoptosis. The drugs inhibited angiogenesis in vitro and inhibited tumour development in vivo with varying potency. In general, results from this study indicated that there was negligible systemic spill-over of bleomycin following IB administration in patients with haemangiomas, suggesting a much lesser risk of developing bleomycin-induced pulmonary fibrosis. This study also showed that test drugs inhibited angiogenesis in vitro and haemangioma development in vivo in a mouse model. Taken together, these observations demonstrate that bleomycin may inhibit haemangioma growth by inhibiting angiogenesis. In addition, mitomycin C, 2-methoxyestradiol, taxol, vincristine, vinblastine, colchicine, nocodazole and cytochalasin D may have potential in the treatment of haemangiomas of infancy, and should be investigated further in a murine haemangioma model to determine effective dose schedules. / Thesis (PhD)--University of Pretoria, 2009. / Physiology / unrestricted

Made available in DSpace on 2016-07-18T17:53:17Z (GMT). No. of bitstreams: 1 Francislaine.pdf: 394781 bytes, checksum: a0d56232957fee86543512d568bcec4c (MD5) Previous issue date: 2015-12-18 / Tea is an extremely popular drink, being the second most commonly consumed in the world. People ingest teas on average two to three times a day, the majority being derived from the Camellia sinensis plant. The beneficial health effects of the consumption of tea from this plant are well known, such as the prevention of cancer, cardiovascular disease and osteoporosis. Despite this, little is known about the action of white tea on reproduction. It is important to evaluate the possible consequences of consumption on luteal and endometrial development since the main catechin, epigallocatechin gallate (EGCG), present in the tea influences the gene expression of VEGF in tumors and this is an important angiogenic factor in the reproductive organs. This study aimed to verify the effects of prolonged intake of white tea on the relative abundance of VEGF mRNA and its receptors, as well as in cell proliferation in the endometrium of superovulated rats. For this purpose, the rats were divided into two groups, control group (n = 30), which received water, and white tea intake group (n = 30). The ovaries and uteri were collected from 10 animals in each group at the end of every month, for three consecutive months, stored in Trizol in a freezer at -80 ° C and the relative abundance of VEGF mRNA, Flt-1 and KDR were subsequently evaluated. In addition, the uteri were histologically analyzed using the silver staining method to detect cell proliferation. The data were evaluated for the assumption of normality (Shapiro-Wilk) and statistical comparisons were performed using the unpaired t test between groups at different collection moments (p <0.05). The relative abundance of VEGF mRNA and its receptors was changed by the tea consumption and there were a lower number of nucleolar organizer regions in endometrial cells. It was concluded that prolonged consumption of white tea interferes the expression of the VEGF system genes in the corpus luteum and decreases cell proliferation in the endometrium of Wistar rats. / O chá é uma das bebidas mais populares e a segunda mais consumida no mundo. A população ingere chás em média, de duas a três vezes ao dia, sendo em sua maioria oriundos da planta Camellia sinensis. São bem conhecidos os efeitos benéficos para a saúde do consumo dos chás provenientes dessa planta, como a prevenção de câncer, de doença cardiovascular e da osteoporose. Apesar disso, pouco se sabe sobre a ação do chá branco na reprodução, sendo importante avaliar as possíveis consequências do seu consumo no desenvolvimento luteal e endometrial. Visto que a principal catequina, a epigalocatequina galato (EGCG) presente neste chá influencia a expressão gênica do Vegf em tumores e este é um importante fator angiogênico dos órgãos reprodutivos, este estudo teve como objetivo verificar o efeito da ingestão do chá branco sobre a abundância relativa do mRNA do Vegf e dos seus receptores,sobre a proliferação celular do endométrio de ratas superovuladas. Para tanto, as ratas foram distribuídas em dois grupos, grupo controle (n=30) que recebeu água e grupo com ingestão de chá branco (n=30). Os ovários e os úteros foram coletados ao final de cada mês de ingestão de chá branco ou água de 10 animais de cada grupo, durante três meses consecutivos, sendo os ovários armazenados em trizol no freezer a -80ºC e posteriormente a abundância relativa de mRNA do Vegf, do Flt-1 e do Kdr foram avaliadas. Além disso, os úteros foram analisados histologicamente pelo método de coloração de prata para detecção de proliferação celular. Os dados foram avaliados quanto ao pressuposto de normalidade (Shapiro-Wilk) e as comparações estatísticas foram realizadas por meio dos testes t não pareado entre os grupos nos diferentes momentos de colheitas (p<0,05). A abundância relativa de mRNA do Vegf e dos seus receptores foi alterada pelo consumo de chá e houve um menor número de regiões organizadoras de nucléolo nas células do endométrio. Conclui-se que a ingestão prolongada de chá branco altera a expressão dos genes do sistema Vegf no corpo lúteo e diminui a proliferação celular do endométrio de ratas Wistar.

Gene therapy techniques delivering exogenous angiogenic growth factors, such as vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (FGF-2), are currently being investigated as potential treatments for ischemia resulting from a variety of conditions, such as peripheral artery disease (PAD) and chronic wounds. Despite these intense efforts, a viable clinical option to promote therapeutic neovascularization remains elusive. Electroporation is a simple in vivo method to deliver normally impermeable molecules, such as plasmid DNA, to a variety of tissues including skin and muscle. This study investigated intradermal injection of plasmids encoding angiogenic growth factors with electroporation as a novel therapeutic approach to increase perfusion in areas of ischemia. Two common animal models of ischemia were employed: a skin flap model, used to study wound healing, and a hindlimb ischemia model, used to investigate potential therapies for PAD. In the skin flap model, delivery of plasmid VEGF with electroporation significantly increased VEGF expression for 5 days after delivery compared to injection of the plasmid alone. While the increase in VEGF expression was short-term, it significantly increased expression of the downstream angiogenic growth factor endothelial nitric oxide synthase, as well as perfusion and healing in the distal area of the skin flap. To facilitate the translation of electroporation to the clinic, a novel electrode configuration was previously designed for cutaneous delivery of plasmids to a large surface area. The design of the Multielectrode Array allows for delivery to a large surface area without the need to increase the applied voltage. Conditions for plasmid delivery with this electrode were optimized and it was then utilized to deliver plasmid FGF-2 (pFGF) to the hindlimb ischemia model. FGF-2 expression, perfusion, and angiogenesis were assessed. FGF-2 expression was significantly higher for 10 days after treatment with pFGF with electroporation compared to injection of pFGF alone. This increase in FGF-2 expression induced a significant increase in perfusion and angiogenesis in the ischemic limb. The research presented here suggests intradermal injection of plasmids encoding angiogenic factors by electroporation is a novel potential therapeutic approach to increase perfusion to areas of ischemia and promote wound healing.

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...

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BackgroundHead and neck squamous cell carcinoma (HNSCC) is a common cancer. Positron emission tomography (PET) with 18F-fluorodeoxyglucose (18F-FDG) is a widely used imaging modality in HNSCC.PurposeTo provide evident data about associations between 18F-FDG PET and histopathology in HNSCC.Material and MethodsThe MEDLINE database was screened for associations between maximum standard uptake values (SUVmax) derived from 18F-FDG PET and histopathological features in HNSCC up to May 2020. Only papers containing correlation coefficients between SUVmax and histopathology were acquired. Overall, 23 publications were collected.ResultsThe following correlations were calculated: KI 67: 12 studies (345 patients), pooled correlation coefficient (PCC): 0.23 (95% confidence interval [CI] 0.06–0.40); hypoxia-inducible factor-1α: eight studies (240 patients), PCC: 0.24 (95% CI 0.06–0.42); microvessel density: three studies (64 patients), PCC: 0.33 (95% CI 0.02–0.65); vascular endothelial growth factor: two studies (59 cases), PCC: 0.27 (95% CI 0.02–0.51); tumor suppressor protein p53: four studies (159 patients), PCC: 0.05 (95% CI –0.41 to 0.51); epidermal growth factor receptor: two studies (124 patients), PCC: 0.21 (95% CI 0.05–0.37); tumor cell count: three studies (67 patients), PCC: 0.18 (95% CI –0.06 to 0.42); tumor cell apoptosis: two studies (40 patients), PCC: 0.07 (95% CI = –0.85 to 0.99); B-cell lymphoma-2 protein: two studies (118 patients); PCC: 0.04 (95% CI –0.65 to 0.74); glucose-transporter 1: 10 studies (317 patients), PCC: 0.20 (95% CI 0.10–0.30).ConclusionSUVmax derived from 18F-FDG PET cannot reflect relevant histopathological features in HNSCC.

No description available.