• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 23
  • 14
  • 6
  • 1
  • Tagged with
  • 42
  • 42
  • 14
  • 14
  • 11
  • 9
  • 7
  • 6
  • 6
  • 6
  • 6
  • 5
  • 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

Assessment of nutrition intervention for patients with unresectable pancreatic cancer in a fish oil supplement trial - does it make a difference?

Davidson, Wendy Louise January 2003 (has links)
Severe and progressive weight loss is a feature of pancreatic cancer but it has been unclear whether dietetic intervention can improve patient outcomes. This study is a post hoc analysis of the extensive data available from the multicentre BH80 Cancer Cachexia trial to examine how patients with unresectable pancreatic cancer respond to intensive dietetic intervention. The BH80 study compared an n-3 fatty acid enriched oral supplement with an isonitrogenous, isocaloric supplement given over an eight week period. Additional qualitative data was also collected and examined for the patients recruited by the Australian sites. The aims were to determine whether achieving weight stabilisation is an appropriate goal of nutrition intervention for people with unresectable pancreatic cancer; to identify determinants of weight stabilisation; and to describe nutrition-related features of patients recruited by the Australian sites, prior to and during intensive nutrition intervention. Data from 107 patients for whom weight change data over an eight week nutrition intervention period was available, was divided into weight losing (less than 1kg lost) and weight stable (less than or equal to 1 kg lost) patients. Group survival duration (Kaplan Meier log rank test) and global quality of life (EORTC QLQ-C30 global health status/quality of life) were compared. Variables including energy intake, BMI, presence of pain, nausea and vomiting, and appetite loss, C reactive protein and stage of disease were also compared to determine predictors of weight stability using logistic regression analysis. This study demonstrates that weight stabilisation is not only achievable for some patients in the short term, but it is also associated with improved outcomes. Those patients who were able to stabilise their weight after eight weeks of oral nutrition support lived longer from baseline and reported better quality of life than those who continued to lose weight. Weight stabilisation is therefore a reasonable and worthwhile goal for this patient group.
12

Interaction between pancreatic cancer and beta cells : intraislet significance of islet amyloid polypeptide /

Wang, Feng, January 1900 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst. / Härtill 6 uppsatser.
13

Tumour marker CA-50 in pancreatic cancer

Pålsson, Birger. January 1993 (has links)
Thesis (doctoral)--Lund University, 1993. / Added t.p. with thesis statement inserted.
14

Tumour marker CA-50 in pancreatic cancer

Pålsson, Birger. January 1993 (has links)
Thesis (doctoral)--Lund University, 1993. / Added t.p. with thesis statement inserted.
15

Análise da densidade da microvasculatura e da expressão do gene p53 no adenocarcinoma pancreático / Evaluation of microvessel density and p53 in pancreatic adenocarcinoma

Jureidini, Ricardo 01 October 2009 (has links)
O adenocarcinoma pancreático é a neoplasia maligna mais comum do pâncreas. A alta taxa de mortalidade deve-se ao diagnóstico tardio e a alta agressividade do tumor. Freqüentemente observam-se indivíduos com neoplasias de mesmo estadio apresentarem sobrevivência diferente. Isso demonstra a necessidade de incluir mais variáveis na caracterização da doença. O processo de angiogênese é essencial para o crescimento tanto do tumor primário, quanto para o metastático. A medida da densidade intratumoral da microvasculatura (DMV) por imunoistoquímica é o método mais confiável para medir a atividade angiogênica tumoral. A perda da função do gene p53 influencia a resposta à quimio e à radioterapia além de regular a angiogênese. A sobrevivência está inversamente relacionada à positividade do p53 e à DMV em neoplasias de mama, pulmão, ovários, estômago, cólon, laringe e bexiga. No adenocarcinoma pancreático os resultados são controversos. Idealizou-se essa pesquisa retrospectiva analisando-se dados clínicos e os resultados de estudos imunoistoquímicos obtidos de adenocarcinomas de pâncreas ressecados com intenção curativa. Analisou-se dados clínicos, patológicos, re-estadiamento e resultados da DMV e da expressão do gene p53 em 49 pacientes. A densidade média de microvasos foi de 46,2 vasos/mm2 sendo que esse valor foi utilizado para dividir os pacientes em grupos de baixa ou alta densidade de vasos. A coloração para p53 nuclear foi considerada positiva em 20 de 49 pacientes (40,8%). A DMV foi significativamente maior nos pacientes com tumores maiores que 3,0 cm e nos pacientes com ressecções incompletas. A expressão do gene p53 e a DMV, não foram fatores preditivos da sobrevivência pós-operatória. Não foi possível verificar relação entre a expressão do gene p53 e a densidade da microvasculatura tumoral / The prognostic significance of microvessel density and the p53 expression was evaluated. Between 1993 and 2006, 49 patients with pancreatic adenocarcinoma were ressected with curative intention. Specimens were stained immunohistochemically with antibodies anti- p53 anti-CD34. Microvessel density (MVD) was assessed scanning ten areas of the tumoral section and counted at a high power in an adequate area. The MVD ranged from 21,2 to 54,2 vessels/mm2 (mean 46,2 vessels/mm2). Specific nuclear staining for p53 was determined positive in 20 patients (40,8%). The overall median survival was 24,1 months after resection and there was no difference in survival rates according to the MVD and p53 positivity. There was also no relation between the MVD and p53 expression. MVD and p53 expression could not predict survival in these patients with pancreatic adenocarcinoma. There was no correlation with p53 expression and intratumoral microvessel density. High MVD was associated with tumor size grater than 3,0 cm and positive margins
16

Studies on the anti-pancreatic cancer effect of Eriocalyxin B (a diterpenoid isolated from Isodon eriocalyx) and the underlying molecular mechanism in vitro and in vivo.

January 2013 (has links)
胰腺癌是一種致死率極高的惡性疾病,在全世界所有的癌症中死亡率排列第八, 在美國排列第四。 很多因素造成了胰腺癌較差的預後,其中包括: 早期檢出率極低; 較少胰腺癌患者的腫瘤適宜手術切除;高轉移率;以及對傳統放療和化療具有較高抗性等。 因此,發展新的治療藥物迫在眉睫。 / 近年來, 植物藥以及從這些植物藥裡分離出的天然化合物, 單獨使用或者與傳統化療藥物合併使用時, 都顯示出對不同類型的癌症具有較好療效。植物藥毛萼香茶菜(唇形科)含有豐富的具有抗癌活性的二萜類化合物。其中毛萼乙素(EriB) 是一個擁有最好抗癌活性的對映-貝殼杉烷型二萜化合物。 基於此背景, 本研究的目標為:利用胰腺癌體外體內模型, 研究EriB的抗胰腺癌活性以及誘導胰腺癌細胞凋亡的機理。 / 體外實驗中, EriB對四種胰腺癌細胞株都顯示了顯著的細胞毒活性,其活性與化療藥物喜樹堿類似。其中, EriB對胰腺癌細胞株CAPAN-2活性最強, 半數致死濃度IC₅₀為0.73 μM。細胞凋亡特徵:細胞核凝聚, 磷脂醯絲氨酸外翻, DNA梯狀條帶以及片斷化,在EriB誘導的胰腺癌細胞株CAPAN-2中出現。此外, EriB還造成癌細胞在細胞週期G2/M期的阻滯。機理研究發現, EriB是通過啟動絲裂原活化蛋白激酶(MAPK), caspase及 p53信號通路來誘導細胞凋亡和細胞週期阻滯的。抗凋亡蛋白與促凋亡蛋白比率(bcl-2/bak)的減少也可能對啟動細胞凋亡內途徑發揮一定作用。除此以外, EriB對癌細胞的細胞毒活性及致凋亡作用依賴于活性氧分子(ROS)的產生。在對細胞進行抗氧化劑預處理的實驗中發現, 只有含巰基基團的抗氧化劑能夠有效的阻斷EriB對癌細胞的活性。進一步實驗證明, EriB對細胞內兩個抗氧化系統: 谷胱甘肽系統及硫氧還蛋白系統的抑制作用導致了ROS在癌細胞中的積聚。同時,ROS的產生啟動了MAPK,熱休克蛋白70以及caspase信號通路,卻抑制了NFκB通路。 / 動物體內實驗證實, 每天對胰腺癌細胞移植瘤裸鼠進行腹腔注射EriB(2.5 毫克/千克),能有效的抑制腫瘤生長, 並且對心臟,肝臟和腎臟沒有引起顯著毒性。 對腫瘤組織的分析表明, 給藥組(EriB)比溶劑對照組出現更多的細胞凋亡, 並產生較多的ROS積聚。 / 綜上所述, 本項研究首次闡述了EriB具有顯著的體內外抗胰腺癌活性。機理研究證明, EriB抑制胰腺癌細胞內兩個含巰基基團的抗氧化系統, 從而導致ROS在細胞中積聚, 並啟動(或抑制)了包括MAPK, p53, caspase和NFB在內的信號通路, 最終導致癌細胞死亡。 此外, 動物體內研究證明EriB的抗腫瘤生長活性和低毒性, 令該化合物具有潛力進一步研究發展成為抗胰腺癌的新藥物。 / Pancreatic cancer is the fourth and eighth leading cause of cancer-related deaths in the U.S. and worldwide, respectively. Its poor prognosis is attributed to its late diagnosis, limitation to surgical resection, aggressive local invasion, and early metastases, as well as high resistance to chemotherapy and radiotherapy. Therefore, a search for an alternative to therapeutic agents is in desperate need. / In recent years, herbal medicines or natural compounds isolated from herbs either used alone or in combination with conventional anti-cancer agents have been shown to have beneficial effects on various cancers. In this context, the Chinese herb Isodon eriocalyx (Dunn.) Hara (family Lamiaceae) is a well-known source of anti-cancer diterpenoids, the most potent one being Eriocalyxin B (EriB, an ent-kauranoid). Therefore, the aims of the present study are to investigate the anti-tumor activities of EriB in human pancreatic adenocarcinoma cells and tumor-bearing mouse model, as well as the underlying mechanisms. / Our results showed that EriB exhibited significant cytotoxic effects on four pancreatic adenocarcinoma cell lines, with potencies being comparable to that of chemotherapeutic agent camptothecin. EriB had the most potent cytotoxicity in CAPAN-2 cells with IC₅₀ = 0.73 μM. The hallmark features of apoptosis, such as nuclear condensation, translocation of phosphatidylserine, DNA laddering, and DNA fragmentation were observed in EriB-treated CAPAN-2 cells. On the other hand, EriB also induced G2/M phase cell cycle arrest. Mechanistic studies revealed that EriB induced apoptosis and cell cycle arrest through the activation of MAPKs (p38, ERK1/2), caspase cascade, and p53/p21/cdk1-cyclinB1 signaling pathways. A decrease in the ratio of anti-apoptotic to pro-apoptotic proteins (bcl-2/bak) also contributed to the activation of intrinsic apoptotic pathway. Further investigation showed that EriB-induced cytotoxic and apoptotic effects were dependent on reactive oxygen species (ROS) production. Such demonstrated effects could be inhibited by pre-treatment with thiol-containing antioxidants. Furthermore, EriB induced ROS was mediated via the inhibition of two main antioxidant systems, namely glutathione and thioredoxin systems. EriB-mediated ROS activated multiple targets or signal pathways, including MAPK, heat shock protein (Hsp) 70, and caspase cascade, while inhibiting the NFκB pathway. / On the other hand, in vivo study demonstrated that daily intraperitoneal administration of EriB (2.5mg/kg/day) in human pancreatic tumor xenografts BALB/c nude mice significantly inhibited tumor growth, but without having toxicity in the heart, liver and kidney. In addition, EriB treatments induced in vivo cell apoptosis and superoxide production as observed in tumor tissues. / In conclusion, the present study reports for the first time that EriB has possessed anti-proliferative activities in pancreatic cancer cells. The anti-proliferative effects of EriB on CAPAN-2 cells could be attributable to the regulation of cellular apoptosis and cell cycle arrest. The inhibitory effects of EriB on two antioxidant systems result in the accumulation of ROS, which in turn activate MAPK, p53, Hsp70 and caspase cascade, while inhibiting NFB pathway and finally leading to pancreatic cancer cell death. Meanwhile, in vivo study further confirms the anti-tumor properties of EriB, suggesting that EriB could be considered as a potential chemotherapeutic agent for patients with pancreatic cancer. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Li, Lin. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 207-230). / Abstracts also in Chinese. / Abstract (English) --- p.i / Abstract (Chinese) --- p.iv / Publications --- p.vi / Acknowledgements --- p.vii / Table of contents --- p.ix / List of figures --- p.xv / List of tables --- p.xix / List of abbreviations --- p.xx / Chapter Chapter1 --- General Introduction --- p.1 / Chapter 1.1 --- The pancreas --- p.2 / Chapter 1.1.1 --- Anatomy of the pancreas --- p.2 / Chapter 1.1.2 --- Histology of the pancreas --- p.4 / Chapter 1.1.3 --- Exocrine pancreas --- p.5 / Chapter 1.1.3.1 --- Structure of secretory acini, ducts and stroma in pancreas --- p.5 / Chapter 1.1.3.2 --- Functions of exocrine pancreas --- p.6 / Chapter 1.1.4 --- Endocrine pancreas --- p.9 / Chapter 1.1.4.1 --- Structure of islets cells --- p.10 / Chapter 1.1.4.2 --- Functions of endocrine pancreas --- p.10 / Chapter 1.1.5 --- Disorders of the pancreas --- p.11 / Chapter 1.2 --- Pancreatic cancer --- p.14 / Chapter 1.2.1 --- Epidemiology --- p.14 / Chapter 1.2.2 --- The risks and causes of pancreatic cancer --- p.15 / Chapter 1.2.3 --- Signs and symptoms of pancreatic cancer --- p.18 / Chapter 1.2.4 --- Types of pancreatic cancer --- p.19 / Chapter 1.2.5 --- Diagnosis of pancreatic cancer --- p.21 / Chapter 1.2.6 --- Staging of pancreatic cancer --- p.27 / Chapter 1.3 --- Treatments for pancreatic cancer --- p.29 / Chapter 1.3.1 --- Surgery --- p.29 / Chapter 1.3.2 --- Chemotherapy --- p.30 / Chapter 1.3.2.1 --- 5-fluorouracil (5-FU) --- p.32 / Chapter 1.3.2.2 --- Gemcitabine (Gem) --- p.33 / Chapter 1.3.2.3 --- Other cytotoxic agents --- p.34 / Chapter 1.3.3 --- Radiotherapy --- p.35 / Chapter 1.3.4 --- Target therapies --- p.37 / Chapter 1.3.4.1 --- Antiangiogenic therapy --- p.37 / Chapter 1.3.4.2 --- Epidermal growth factor receptor (EGFR) signaling inhibitors --- p.39 / Chapter 1.3.4.3 --- Hedgehog and Notch signaling pathways inhibitors --- p.41 / Chapter 1.3.5 --- Gene therapy --- p.42 / Chapter 1.3.6 --- Immunotherapy --- p.45 / Chapter 1.3.7 --- Combination therapies --- p.46 / Chapter 1.4 --- Molecular targets for pancreatic cancer chemotherapy --- p.49 / Chapter 1.4.1 --- Therapies-induced apoptosis --- p.49 / Chapter 1.4.1.1 --- Caspase cascade and bcl-2 Family --- p.49 / Chapter 1.4.1.2 --- Role of mitogen-activated protein kinases (MAPKs) in apoptosis --- p.50 / Chapter 1.4.2 --- Nuclear factor-κB activation in pancreatic cancer --- p.50 / Chapter 1.4.3 --- The PI3K and AKT pathway --- p.51 / Chapter 1.4.4 --- JAK/STAT pathway --- p.51 / Chapter 1.4.5 --- Other molecular targets --- p.52 / Chapter 1.5 --- Herbal medicine as an alternative treatment for cancer treatment --- p.53 / Chapter 1.5.1 --- Herbal medicines for different types of cancer treatment --- p.53 / Chapter 1.5.2 --- Herbal medicines for pancreatic cancer treatment --- p.59 / Chapter 1.6 --- Introduction of Isodon eriocalyx (Dunn.) Hara --- p.61 / Chapter 1.6.1 --- Background of Isodon genus and Isodon eriocalyx (Dunn.) Hara --- p.61 / Chapter 1.6.2 --- Diterpenoids from Isodon species and their activities --- p.62 / Chapter 1.6.3 --- The potential anti-cancer activity of Eriocalyxin B, a diterpenoid isolated from Isodon eriocalyx (Dunn.) Hara --- p.62 / Chapter 1.7 --- Aims and objectives of this study --- p.66 / Chapter Chapter 2 --- Eriocalyxin B induces apoptosis and cell cycle arrest in pancreatic adenocarcinoma cells through caspase- and p53-dependent pathways --- p.67 / Chapter 2.1 --- Introduction --- p.68 / Chapter 2.2 --- Materials and methods --- p.71 / Chapter 2.2.1 --- Preparation and quality control of Eriocalyxin B --- p.71 / Chapter 2.2.2 --- Materials --- p.72 / Chapter 2.2.3 --- Cell culture --- p.72 / Chapter 2.2.4 --- Preparation of human peripheral blood mononuclear cells (PBMC) --- p.73 / Chapter 2.2.5 --- Cytotoxicity assay --- p.75 / Chapter 2.2.6 --- Hoechst 33258 staining for morphological evaluation --- p.76 / Chapter 2.2.7 --- DNA fragmentation detection by DNA ladder --- p.76 / Chapter 2.2.8 --- Cell death detection ELISA --- p.77 / Chapter 2.2.9 --- Apoptosis detection by flow cytometry --- p.78 / Chapter 2.2.10 --- Cell cycle analysis by flow cytometry --- p.78 / Chapter 2.2.11 --- Western blot analysis --- p.79 / Chapter 2.2.12 --- Statistical analysis --- p.80 / Chapter 2.3 --- Results --- p.81 / Chapter 2.3.1 --- EriB induces cytotoxic effect in human pancreatic cancer cells --- p.81 / Chapter 2.3.2 --- EriB induces apoptosis in CAPAN-2 cells --- p.85 / Chapter 2.3.3 --- Activation of pro-apoptotic caspases in EriB-treated CAPAN-2 cells --- p.89 / Chapter 2.3.4 --- Modulation of bcl-2/bak ratio in EriB-treated CAPAN-2 cells --- p.92 / Chapter 2.3.5 --- EriB causes G2/M cell cycle arrest --- p.94 / Chapter 2.3.6 --- EriB modulates expression of G2/M cell cycle regulatory proteins through activation of the p53 pathway --- p.96 / Chapter 2.4 --- Discussion --- p.99 / Chapter Chapter 3 --- Eriocalyxin B induces apoptosis in pancreatic cancer CAPAN-2 cells via mediation of reactive oxygen species --- p.107 / Chapter 3.1 --- Introduction --- p.108 / Chapter 3.2 --- Materials and methods --- p.113 / Chapter 3.2.1 --- Materials --- p.113 / Chapter 3.2.2 --- Cell culture and MTT assay --- p.113 / Chapter 3.2.3 --- Apoptosis detection by flow cytometry --- p.114 / Chapter 3.2.4 --- Reactive oxygen species (ROS) detection by flow cytometry --- p.114 / Chapter 3.2.5 --- Glutathione assessment --- p.115 / Chapter 3.2.6 --- Glutathione peroxidase (GPx) activity detection --- p.116 / Chapter 3.2.7 --- Thioredoxin reductase (TrxR) activity detection --- p.116 / Chapter 3.2.8 --- Nuclear and cytosolic fractionation --- p.117 / Chapter 3.2.9 --- Western blot analysis --- p.117 / Chapter 3.2.10 --- Electrophoretic mobility shift assay --- p.119 / Chapter 3.2.11 --- Statistical analysis --- p.119 / Chapter 3.3 --- Results --- p.120 / Chapter 3.3.1 --- Thiol-containing antioxidants inhibits EriB-induced cytotoxic effects --- p.120 / Chapter 3.3.2 --- Thiol-containing antioxidants inhibits EriB-induced apoptotic effects --- p.122 / Chapter 3.3.3 --- Effects of EriB on hydrogen peroxide production --- p.125 / Chapter 3.3.4 --- EriB depletes glutathione level and suppresses GPx activity --- p.128 / Chapter 3.3.5 --- EriB inhibits thioredoxin system and activates ASK1 --- p.130 / Chapter 3.3.6 --- EriB increases Hsp70 and cleaved-PARP expression through ROS --- p.134 / Chapter 3.3.7 --- EriB inhibits NFkB pathway in CAPAN-2 cells --- p.137 / Chapter 3.4 --- Discussion --- p.142 / Chapter Chapter 4 --- In vivo study of the anti-tumor efficacy of Eriocalyxin B in human pancreatic tumor xenograft model --- p.149 / Chapter 4.1 --- Introduction --- p.150 / Chapter 4.2 --- Materials and methods --- p.154 / Chapter 4.2.1 --- Establishment of a subcutaneous pancreatic cancer xenograft model --- p.154 / Chapter 4.2.2 --- Evaluation of the effects of EriB on tumor growth --- p.155 / Chapter 4.2.2.1 --- Pilot study for EriB and camptothecin treatment --- p.155 / Chapter 4.2.2.2 --- Confirmation study of effective dose of EriB --- p.156 / Chapter 4.2.2.3 --- Dose-comparison study of CPT-11 --- p.156 / Chapter 4.2.2.4 --- Comparison study of EriB and CPT-11 treatments --- p..157 / Chapter 4.2.3 --- Measurement of plasma-specific enzyme levels --- p.157 / Chapter 4.2.4 --- Assays of terminal deoxytransferase-catalyzed DNA nick-end labeling (TUNEL) --- p..158 / Chapter 4.2.5 --- Histological evaluation --- p.159 / Chapter 4.2.6 --- Detection of superoxide by DHE staining --- p.159 / Chapter 4.2.7 --- Establishment of an orthotopic model (SW1990) of pancreatic cancer and detection of the plasma biomarker CA19-9 --- p.160 / Chapter 4.2.7.1 --- Detection of CA19-9 expression by immunofluorescent staining and western blot --- p.161 / Chapter 4.2.7.2 --- Establishment of an orthotopic pancreatic cancer xenograft model by SW1990 cells --- p.162 / Chapter 4.2.8 --- Statistical analysis --- p.164 / Chapter 4.3 --- Results --- p.165 / Chapter 4.3.1 --- EriB inhibits the growth of CAPAN-2 human pancreatic tumor xenografts --- p.165 / Chapter 4.3.2 --- EriB treatments induce cell apoptosis in tumor tissues --- p.173 / Chapter 4.3.3 --- Toxicity tests for EriB --- p.175 / Chapter 4.3.3.1 --- Plasma enzyme levels after EriB treatments --- p.175 / Chapter 4.3.3.2 --- No apparent alterations in histology of the heart, liver and kidney tissues --- p..176 / Chapter 4.3.4tEriB induces superoxide production in the tumor tissues --- p.178 / Chapter 4.3.5 --- Successful establishment of an orthotopic xenograft model --- p.180 / Chapter 4.4 --- Discussion --- p.184 / Chapter Chapter 5 --- General Discussion --- p.188 / Chapter 5.1 --- Discussion --- p.189 / Chapter 5.2 --- Conclusion --- p.204 / Chapter 5.3 --- Limitations of the study --- p.205 / Chapter 5.4 --- Future work --- p.206 / Chapter Chapter 6 --- References --- p.207
17

Análise da densidade da microvasculatura e da expressão do gene p53 no adenocarcinoma pancreático / Evaluation of microvessel density and p53 in pancreatic adenocarcinoma

Ricardo Jureidini 01 October 2009 (has links)
O adenocarcinoma pancreático é a neoplasia maligna mais comum do pâncreas. A alta taxa de mortalidade deve-se ao diagnóstico tardio e a alta agressividade do tumor. Freqüentemente observam-se indivíduos com neoplasias de mesmo estadio apresentarem sobrevivência diferente. Isso demonstra a necessidade de incluir mais variáveis na caracterização da doença. O processo de angiogênese é essencial para o crescimento tanto do tumor primário, quanto para o metastático. A medida da densidade intratumoral da microvasculatura (DMV) por imunoistoquímica é o método mais confiável para medir a atividade angiogênica tumoral. A perda da função do gene p53 influencia a resposta à quimio e à radioterapia além de regular a angiogênese. A sobrevivência está inversamente relacionada à positividade do p53 e à DMV em neoplasias de mama, pulmão, ovários, estômago, cólon, laringe e bexiga. No adenocarcinoma pancreático os resultados são controversos. Idealizou-se essa pesquisa retrospectiva analisando-se dados clínicos e os resultados de estudos imunoistoquímicos obtidos de adenocarcinomas de pâncreas ressecados com intenção curativa. Analisou-se dados clínicos, patológicos, re-estadiamento e resultados da DMV e da expressão do gene p53 em 49 pacientes. A densidade média de microvasos foi de 46,2 vasos/mm2 sendo que esse valor foi utilizado para dividir os pacientes em grupos de baixa ou alta densidade de vasos. A coloração para p53 nuclear foi considerada positiva em 20 de 49 pacientes (40,8%). A DMV foi significativamente maior nos pacientes com tumores maiores que 3,0 cm e nos pacientes com ressecções incompletas. A expressão do gene p53 e a DMV, não foram fatores preditivos da sobrevivência pós-operatória. Não foi possível verificar relação entre a expressão do gene p53 e a densidade da microvasculatura tumoral / The prognostic significance of microvessel density and the p53 expression was evaluated. Between 1993 and 2006, 49 patients with pancreatic adenocarcinoma were ressected with curative intention. Specimens were stained immunohistochemically with antibodies anti- p53 anti-CD34. Microvessel density (MVD) was assessed scanning ten areas of the tumoral section and counted at a high power in an adequate area. The MVD ranged from 21,2 to 54,2 vessels/mm2 (mean 46,2 vessels/mm2). Specific nuclear staining for p53 was determined positive in 20 patients (40,8%). The overall median survival was 24,1 months after resection and there was no difference in survival rates according to the MVD and p53 positivity. There was also no relation between the MVD and p53 expression. MVD and p53 expression could not predict survival in these patients with pancreatic adenocarcinoma. There was no correlation with p53 expression and intratumoral microvessel density. High MVD was associated with tumor size grater than 3,0 cm and positive margins
18

Anti-tumor effects and mechanisms of pegylated human recombinant arginase (PEG-BCT-100) in pancreatic cancer cells: 一種聚乙二醇重組人精氨酸酶在胰腺癌細胞中的抗癌效應及機制研究 / 一種聚乙二醇重組人精氨酸酶在胰腺癌細胞中的抗癌效應及機制研究 / CUHK electronic theses & dissertations collection / Anti-tumor effects and mechanisms of pegylated human recombinant arginase (PEG-BCT-100) in pancreatic cancer cells: Yi zhong ju yi er chun zhong zu ren jing an suan mei zai yi xian ai xi bao zhong de kang ai xiao ying ji ji zhi yan jiu / Yi zhong ju yi er chun zhong zu ren jing an suan mei zai yi xian ai xi bao zhong de kang ai xiao ying ji ji zhi yan jiu

January 2015 (has links)
Pancreatic cancer is one of the most devastating human cancers with the lowest survival rate among 24 commonly diagnosed cancers. It is the seventh and the sixth leading cause of cancer-related deaths in the world and Hong Kong respectively. The current pancreatic cancer treatment options, have limited efficacy and undesirable side effects. Because of the high mortality rate and unsatisfactory treatment outcome, it is necessary to develop new strategies for pancreatic cancer therapy. / In human, an abundant arginine reserve is known to be crucial for tumor cell proliferation. Arginine is a semi-essential amino acid because most of the somatic cells can re-synthesize it from other metabolites like citrulline in urea cycle. However, arginine auxotrophy is observed in certain tumors, such as hepatocarcinoma, melanoma and sarcoma, where restriction or depletion of arginine will lead to tumor death. Further studies have found that deficiency in either argininosuccinate synthetase 1 (ASS1) or ornithine transcarbamylase (OTC) expression contributes to arginine auxotrophy in these tumors. These findings implicated the potential of using arginine deprivation as a novel pancreatic cancer treatment strategy. / PEG-BCT-100 is a pegylated recombinant human arginase that metabolizes arginine into urea and ornithine. This study examined the preclinical anti-tumor efficacy of PEG-BCT-100 and the underlying mechanism in pancreatic cancer. Six pancreatic cancer cell lines AsPC-1, BxPC-3, CFPAC-1, Capan-2, MIA PaCa-2 and Panc10.05 were used as in vitro cell model. Cell growth was either completely stopped or dramatically reduced in arginine-free medium, suggesting pancreatic cancer cells were arginine auxotrophic. The protein and mRNA expression levels of the ASS1, OTC and argininosuccinate lyase (ASL), which are enzymes involved in arginine, were studied. The results showed that ASL was highly expressed in all cell lines, suggesting it is not an essential regulator in arginine auxotrophy in pancreatic cancer. On the other hand, ASS1 was only detected in BxPC-3 and CFPAC-1, while OTC was undetectable in all cell lines in both mRNA and protein levels. The effect of PEG-BCT-100 was illustrated via cell cycle progression, cell proliferation and viability. Single drug effect combining PEG-BCT-100 with other anti-tumor drugs, such as 5-FU and gemcitabine, was further explored. Synergistic effect of PEG-BCT-100 and gemcitabine under combination of PEG-BCT-100 and gemcitabine was observed in CFPAC-1 and MIA PaCa-2. Overexpression of OTC and ASS1 decreased the sensitivity of towards PEG-BCT-100 significantly. Taken together, OTC deficiency is a potential indicative marker for the sensitivity of arginine depletion treatment in pancreatic cancer. / 胰腺癌是最具毀滅性的人類癌症之一,在二十四種常見的癌症中,它有着最低的存活率。儘管不在發病率最高的十種癌症中,胰腺癌仍舊是世界第七大致死癌症,以及香港第六大致死癌症。手術治療,放射治療,以及化學藥物治療是現今常用的胰腺癌治療手段,但是這些療法不是限制繁多,就是收效甚微,並常常伴有強烈的副作用。由於胰腺癌具有很高的致死率以及缺乏有效的治療方法,所以新的治療策略亟待開發。 / 於人類而言,精氨酸是一種半必需氨基酸,因爲它可以通過尿素循環中的其他代謝產物,如鳥氨酸以及瓜氨酸,重新合成。然而,精氨酸缺陷出現在多種腫瘤中,像肝癌,黑色素瘤,以及血癌。限制或者減少精氨酸的供應會導致這些腫瘤死亡。除此之外,腫瘤細胞的快速生長也依賴於充足的精氨酸。進一步的研究表明,在這些腫瘤中,精氨琥珀酸合成酶1(ASS1)或者鳥氨酸氨甲醯基轉移酶(OTC)的任意一個缺乏都會導致精氨酸缺陷。本文將探討將剝奪精氨酸作爲一種新策略來治療胰腺癌的可行性。 / PEG-BCT-100又名金氨素,是一種聚乙二醇化重組人精氨酸酶,它可以催化精氨酸分解爲尿素和鳥氨酸。我們研究了PEG-BCT-100在胰腺癌細胞中的抗癌效果以及探討了與其相關的作用機理。在我們的研究中,AsPC-1, BxPC-3, CFPAC-1, Capan-2, MIA PaCa-2以及Panc10.05這六個細胞株用作體外的細胞模型。爲了評估PEG-BCT-100治療胰腺癌的可行性,我們首先調查了精氨酸對胰腺癌細胞的重要性。通過將這些胰腺癌細胞培養在有精氨酸供應和沒有精氨酸供應的完全培養基中,我們發現剝奪精氨酸能完全停止或者極大地減少了胰腺癌細胞的生長。這說明了這些胰腺癌細胞也都是精氨酸營養缺陷型的細胞。通過蛋白印跡和實時定量聚合酶鏈式反應實驗,我們進一步研究了精氨酸代謝相關基因在這些胰腺癌細胞中的表達水平。結果表明,精氨琥珀酸裂解酶(ASL)在全部的六條細胞系中都有被檢測到。ASS1只出現在BxPC-3和CFPAC-1中。然而在全部的細胞中,無論是蛋白質水平還是mRNA水平,OTC都沒有被檢測到。緊接着,我們研究了PEG-BCT-100在胰腺癌細胞活力,細胞增殖,細胞週期以及細胞凋亡等方面的影響。結果表明,PEG-BCT-100可以從多個方面抑制胰腺癌細胞。我們還嘗試探索了PEG-BCT-100與其他胰腺癌治療藥物在胰腺癌細胞中的聯合使用效果。然後發現PEG-BCT-100與吉西他滨(gemcitabine)聯合使用具有協同效果。最後,我們構建了四種不同表達類型的MIA PaCa-2細胞模型:(ASS1-/OTC-), (ASS1-/OTC+), (ASS1+/OTC-)以及(ASS1+/OTC+)。接着我們測試了PEG-BCT-100在這些細胞模型中的效果。結果表明,同時在MIA PaCa-2細胞中表達ASS1和OTC可以明顯地提高其對PEG-BCT-100的抗性,單表達其中一個基因對PEG-BCT-100的抗性也有些許提高,但效果不如雙表達明顯。 / 總而言之,對於胰腺癌細胞而言,精氨酸是必不可少的。PEG-BCT-100有很明顯的胰腺癌效果。在胰腺癌中,OTC的表達情況可以作爲預估PEG-BCT-100治療效果的重要生物標誌。 / Deng, Haohao. / Thesis M.Phil. Chinese University of Hong Kong 2015. / Includes bibliographical references (leaves 111-117). / Abstracts also in Chinese. / Title from PDF title page (viewed on 14, October, 2016). / Deng, Haohao. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only.
19

EZH2 silences microRNA-218 in human pancreatic ductal adenocarcinoma by inducing formation of heterochromatin. / CUHK electronic theses & dissertations collection

January 2013 (has links)
Li, Chi Han Samson. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 158-175). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
20

Marcadores inflamatórios de pacientes com neoplasia da confluência biliopancreática: níveis sanguíneos e expressão gênica / Inflammatory markers of patients with biliopancreatic confluence neoplasia: blood levels and gene expression

Merino, Susana 08 December 2017 (has links)
Introdução: O câncer da confluência biliopancreática tem alta letalidade e prognóstico reservado, atribuído à associação da agressividade biológica e ao quadro clínico silencioso. A inflamação tem papel fundamental no desenvolvimento e na progressão da caquexia, induzida pela expressão de citocinas produzidas pelo tumor e/ou liberadas pelo sistema imunológico. Nos últimos anos, tem sido documentada a variabilidade na expressão gênica de citocinas que regulam os mecanismos envolvidos na caquexia neoplásica. Objetivos: Em amostras de sangue periférico de pacientes com neoplasia da confluência biliopancreática, avaliar a concentração da interleucina 6 (IL-6), fator de necrose tumoral alfa (TNF-?), interferon-gama (INF- ?) e interleucina 10 (IL-10), além da expressão gênica dessas citocinas, do receptor tipo 1 do fator de necrose tumoral (TNFR1), do receptor tipo 2 do fator de necrose tumoral (TNFR2), da zinco-alfa2-glicoproteina (ZAG) e do receptor ativado por proliferador de peroxissoma gama (PPAR-?). Além disso, o estudo visou identificar possíveis diferenças nos dados avaliados entre os pacientes classificados de acordo com a presença ou não de caquexia neoplásica. Casuística: O estudo transversal foi conduzido com 17 pacientes adultos de ambos os gêneros em pré-operatório imediato de neoplasia da confluência biliopancreática (Grupo Câncer), além de 15 indivíduos controles em pré-operatório de herniorrafia (Grupo Controle). Os pacientes com neoplasia foram classificados de acordo com a presença de caquexia (Subgrupo Caquexia, n=8) e aqueles sem diagnóstico de caquexia (Subgrupo Semcaquexia, n=9). Métodos: A ingestão alimentar e a composição corporal foram avaliadas em todos os voluntários. O questionário de fadiga foi aplicado nos indivíduos com neoplasia. O diagnóstico de caquexia foi feito a partir de critérios pré-estabelecidos. As citocinas inflamatórias IL-6, TNF-?, INF-? e IL-10 foram dosadas no sangue periférico. A expressão gênica dessas citocinas inflamatórias, dos receptores de TNF-?, da ZAG e do PPAR-? foi feita em sangue total. A análise estatística foi realizada com o auxílio de software Statistica, versão 8.0®. Resultados: Não houve diferença na ingestão energética [1827 (1489-2166) vs 1691 (1380-2003) kcal, p=0,56] e proteica [91,6 (74-109) vs 101 (89-114) g, p=0,30] dos indivíduos com câncer ou controles, exceto pela maior ingestão de lipídeos [69,0 (53,5-84,5) vs 42,7 (33,4-52,1) g, p=0,01] e menor consumo de vitamina A [382 (152-612) vs 1346 (1032-1659) ?g, p=0,001] no Grupo Câncer em relação ao Grupo Controle, respectivamente. Houve perda de peso em relação ao habitual em 15 dos 17 pacientes (13,1 ? 11,0%) antes do procedimento cirúrgico, embora as variáveis de composição corporal estivessem semelhantes entre os dois grupos de estudo. Os pacientes com neoplasia apresentavam menores concentrações plasmáticas de albumina [3,8 (3,5-4,0) vs 4,4 (4,3-4,5) g/dL, p<0,001], transferrina [166 (140-192) vs 241 (212-270) mg, p=0,001], ferro [80,8 (67,7-93,9) vs 107 (82-131) ?g/dL, p=0,003], zinco [79,9 (66-93,7) vs 97,4 (88-107) ?g%, p=0,001] e vitamina A [0,7 (0,6-0,8) vs 1,3 (1,0-1,5) umol/L, p<0,001], além de maiores níveis de glicemia [115 (118-193) vs 98,6 (82-115) mg/dL, p=0,003], proteína C reativa [2,7 (0,9-4,5) vs 0,2 (0,2-3,3) mg/dL, p<0,001], ferritina [985 (347-1623) vs 170 (85-255) ng/dL, p=0,003] e cobre [147 (122-177) vs 107 (92-121) ?g%, p=0,03] em relação aos controles, respectivamente. A concentração sérica das citocinas IL-6 [7,2 (4,2-10,1) vs 2,0 (1,4-2,5) pg/mL, p<0,001], TNF- ? [24,6 (18,7-30,5) vs 15,2 (11,3-19,1) pg/mL, p=0,02] e IL-10 [13,3 (8,5-18,2) vs 4,4 (2,8- 6,1) pg/mL, p<0,001] foram maiores no Grupo Câncer. O RNAm do INF-? (p=0,008), 8 TNFR1 (p=0,003), IL-10 (p=0,002) e PPAR-? (p=0,002) foram mais expressos nos pacientes com neoplasia. O Subgrupo Caquexia apresentou menor ingestão energética (p=0,03) e proteica (p=0,04), maior intensidade de fadiga (p=0,003), maior perda de peso (p=0,02) e menores níveis séricos de zinco (p=0,05). Dentre as citocinas, apenas a concentração de IL-6 (p=0,04) foi maior no Subgrupo Caquexia, enquanto que a expressão gênica do INF-? (p=0,04) foi maior nos pacientes com caquexia. Conclusões: Apesar da perda de peso, os marcadores de ingestão alimentar e composição corporal foram pouco alterados nos pacientes com neoplasia da confluência biliopancreática. As alterações laboratoriais foram evidentes nos pacientes com neoplasia, mostrando uma resposta inflamatória sistêmica. O aumento da expressão gênica da IL-10 sugere que as células do sangue periférico estão envolvidas no aumento sérico desta citocina. Apesar do aumento da concentração sérica do IL-6 e TNF-? nos pacientes com neoplasia, não houve aumento da expressão gênica dessas citocinas em sangue periférico. Tais dados sugerem que a IL-6 e o TNF-? são produzidos por outras células do sistema imune, distintas dos macrófagos circulantes. O aumento da expressão gênica de INF-? no sangue periféricos dos pacientes com neoplasia não foi acompanhado por maior concentração sérica dessa citocina, por possíveis mecanismos epigenéticos. Os genes do PPAR-? e do TNFR1 foram mais expressos nos pacientes com neoplasia. A caquexia foi definida em 8 pacientes, que apresentaram maior perda ponderal e menor ingestão nutricional. A concentração sérica de IL-6 foi maior no Subgrupo Caquexia, indicando a relação entre essa citocina e o estado caquético. Embora a concentração sérica de INF-? fosse semelhante entre sujeitos com ou sem caquexia, a expressão gênica dessa citocina foi maior nos pacientes caquéticos. / Introduction: Biliopancreatic confluence cancer has a high lethality and a reserved prognosis, attributed to the association of biological aggressiveness and the silent clinical picture. Inflammation plays a key role in the development and progression of cachexia, induced by the expression of cytokines produced by the tumor and/or released by the immune system. In recent years, it has been documented the variability in the genetics of cytokines regulating the mechanisms involved in neoplastic cachexia. Objectives: To evaluate the concentration of interleukin-6 (IL-6), tumor necrosis factor alpha (TNF-?), interferon-gamma (IFF-?) and interleukin 10 (IL-10) in samples of peripheral blood from patients with biliopancreatic confluence neoplasia, in addition to the gene expression of these cytokines, tumor necrosis factor receptor 1 (TNFR1), type 2 receptor tumor necrosis factor (TNFR2), zinc receptor alpha2-glycoprotein (ZAG) and peroxisome proliferator-activated gamma (PEAR-?). Besides, this study aimed to identify possible differences in the data among patients who were classified according to the presence or absence of neoplastic cachexia. Casuistic: The cross-sectional study was carried out with 17 patients of both genders in the immediate preoperative period of neoplasia of the biliopancreatic confluence (Cancer Group), in addition to 15 individual control in the preoperative period of hernia removal surgery (Control Group). Patients with neoplasia were classified according to the presence of cachexia (Subgroup Cachexia, n=8) and those without it (Subgroup Without-cachexia, n=9). Methods: Food intake and body composition were evaluated in all volunteers. The fatigue questionnaire was applied in individuals with neoplasia. The diagnosis of cachexia was based on pre-established criteria. Inflammatory cytokines IL-6, TNF-?, INF-? and IL-10 were measured in peripheral blood. The gene expression of inflammatory cytokines, TNF-?\' receptors, ZAG and PPAR were made in whole blood. Statistical analysis was performed using Statistica software, version 8.0®. Results: There was no difference in energy intake [1827 (1489-2166) vs 1691 (1380-2003) kcal, p=0.56] and protein [91.6 (74-109) vs 101 (89-114) g, p=0.30] of individuals with cancer or controls, except for the higher lipid intake [69.0 (53.5-84.5) vs 42.7 (33.4-52.1) g, p=0,01] and lower intake of vitamin A [382 (152-612) vs 1346 (1032-1659) ,µg, p=0.001] in the Cancer Group related to Control Group, respectively. There was weight loss from the usual in 15 of the 17 patients (13.1 + 11.0%) prior to the surgical procedure, although body composition variables were similar between the two study groups. Patients with neoplasia had lower plasma albumin concentrations [3.8 (3.5-4.0) vs 4.4 (4.3-4.5) g/dL, p <0.001], transferrin [166 (140-192) vs 241 (212-270) mg/dL, p=0,001], iron [80.8 (67.793.9) vs 107 (82-131) ,µg/dL, p=0.003], zinc [79.9 (66-93.7) vs 97.4 (88-107) µg%, p=0.001] and vitamin A [0.7 (0.6-0.8) vs 1.3 (1, 0-1.5) umol/L, p <0.001], as well as higher glycemia levels [115 (118-193) vs 98.6 (82-115) mg/dL, p=0.003], C-reactive protein 2.7 (0.9-4.5) vs 0.2 (0.2-3.3) mg/dL, p <0.001], ferritin [985 (347-1623) vs 170 (85-255) ng/dL, p=0.003] and copper ~147 (122-177) vs 107 (92-121) µg%, p=0.03] relative to the controls, respectively. The serum concentration of IL-6 cytokines [7.2 (4.2-10.1) vs. 2.0 (1.4-2.5) pg/mL, p <0.001], TNF-? [24.6 (18.7-30.5) vs 15.2 (11.3-19.1) pg/mL, p=0.02] and IL-10 [13.3 (8.5-18.2) vs 4.4 (2.8-6.1) pg/mL, p=0.008) were higher in the Cancer Group. The mRNA of INF-? (p=0.008), TNFR1 (p=0.003), IL-10 (p=0.002) and PPAR-? (p=0.002) were more expressed in patients with neoplasia. The Caquexy Subgroup had lower energetic (p=0.03) and protein intake (p=0.04), higher fatigue intensity (p=0.003), greater weight loss (p=0.02) and lower serum levels of zinc (p=0.05). Among the cytokines, only a concentration of IL-6 (p=0.04) was higher than the Cachexia Subgroup, whereas the gene expression of INF-? (p=0.04) was higher in patients with cachexia. Conclusions: Despite the weight loss, dietary intake markers and body composition were slightly altered in patients with biliopancreatic confluence neoplasia. In patients with neoplasia, laboratory findings were evident showing a systemic inflammatory response. The increasing gene expression of IL-10 suggests that peripheral blood cells are involved in the serum increase of this cytokine. Despite the increased concentration of IL-6 and TNF-? in neoplasia patients, there was no increase in gene expression in peripheral blood cytokines. These data suggest that IL-6 and TNF-? are produced by other cells of the immune system, other than circulating macrophages. The increasing gene expression of INF-? in the peripheral blood of patients with neoplasia was not accompanied by a higher serum concentration of this cytokine, due to possible epigenetic mechanisms. The PPAR-? and TNFR1 genes were more expressed in patients with neoplasia. Cachexia was defined in 8 patients, who presented greater weight loss and lower nutritional intake. The serum concentration of IL-6 was higher in the Cachexia Subgroup, indicating the relation between this cytokine and the cachectic state. Although the serum INF-? concentration was similar between individuals with or without cachexia, the gene expression of this cytokine was higher in cachectic patients

Page generated in 0.0801 seconds