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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Modulation of the immune response to surgical trauma and malignancy with recombinant interleukin-2

Deehan, David J. January 1996 (has links)
This thesis evaluated the role of rIL-2 in patients with advanced colorectal cancer and also, as a perioperative regime, in patients with localized colorectal cancer undergoing surgical resection. Twenty patients with advanced colorectal cancer received up to six cycles of chemoimmunotherapy, each consisting of 5-fluorouracil, levamisole and rIL-2 at 18x10<SUP>6</SUP>IU/m<SUP>2</SUP>/24 for 120 hours. Responding patients were found to have significantly lower pre-treatment serum IL-6 and soluble IL-2 receptor levels, compared with non-responders. Differential patterns of host cytokine release were also identified. Haemodynamic monitoring found that indices of rIL-2-mediated toxicity, e.g. weight gain correlated with alterations in serum cytokine concentrations. In a separate study, eighteen patients, undergoing curative surgery for localized colorectal cancer, were randomized to receive placebo or bolus low-dose subcutaneous rIL-2 for three days preoperatively. rIL-2 was found to significantly enhance host antitumour natural cytotoxicity, monocyte activity and immune cell surface activation marker expression (e.g. CD25). Circulating levels of key host cytokines (e.g. interleukin-6, soluble interleukin-2 receptor) were elevated in the immediate postoperative period in these patients. Mesenteric release of key cytokines was determined in patients undergoing resection for benign and malignant colorectal disease through portal sampling at surgery. Higher patterns of release were found in patients with malignancy suggesting local modulation of immune activity. rIL-2 has been found to beneficially enhance host immune reactivity in patients with localized and advanced colorectal cancer. The nephrotoxic potential of rIL-2 therapy was determined through urinary enzyme release, plasma renin and standard blood biochemistry measurements. RIL-2, when administered carefully, may form the basis of further adjuvant immunotherapy in both the peri-operative period and in patients with advanced colorectal cancer.
32

Does geography influence the treatment and outcomes of colorectal cancer in the province of Manitoba?

Helewa, Ramzi M. 09 August 2012 (has links)
Background: Colorectal cancer (CRC) is the third most common cancer in Manitoba. We sought to determine if regional differences exist for treatments, wait times, and quality measures for Manitobans with CRC. Methods: A population-based historical cohort analysis for patients diagnosed with CRC between 2004 and 2006 was undertaken using administrative databases. Results: 2086 patients were diagnosed with Stage I-IV CRC between 2004 and 2006. Diagnosis wait times and treatment wait times were longer in Winnipeg than rural Manitoba. There were no differences between Winnipeg and rural Manitoba in rates of total colonic examination, adequate lymphadenectomy, and consultations with oncologists. Rural patients with rectal cancer experienced higher local recurrence and mortality rates than urban patients. Conclusion: This study establishes population-based benchmarks for the quality of CRC therapy in Manitoba. Minimal geographic differences exist for quality measures. For rectal cancer local recurrence, rural patients represent an important area for quality improvement initiatives.
33

The analysis of signalling pathways in sporadic colorectal carcinoma using tissue microarrays

Mckenzie, Gavin, Medical Sciences, Faculty of Medicine, UNSW January 2008 (has links)
Colorectal carcinoma arises through sequential genetic changes whereby an adenoma develops from normal colonic epithelium and then becomes a carcinoma. Critical to this process is two forms of mutually exclusive genomic instability ?? chromosomal instability (CIN) and microsatellite instability (MSI). The colorectal tumours that develop from each of these pathways have distinct pathological and molecular differences. Most MSI+ colorectal carcinomas are associated with the CpG island methylator phenotype (CIMP) - an epigenetic phenomenon where a specific and consistent group of genes are silenced through promoter methylation. However, over half of fall CIMP+ colorectal tumours are microsatellite stable (MSS). It is well known that the WNT/β-catenin signalling pathway is instrumental in the initiation and development of CIN type tumours but it is less clear whether this pathway has any significant involvement in MSI+ or methylated tumours. The role of the PI3K1AKT signalling pathway in the development of solid human tumours has only recently been established and the affects of abnormal PI3K/AKT signalling in sporadic colorectal carcinomas is yet to be fully elucidated. The objective of this thesis was to investigate the involvement of the WNT/β-catenin and PI3K/AKT signalling pathways in the CIN, MSI+ and methylated subgroups of sporadic colorectal carcinoma. To achieve this, the expression patterns of β-catenin, p-AKT and PTEN were identified by immunohistochemistry on sections from tissue microarrays consisting of cores from a large group of sporadic colorectal carcinomas. Each of these proteins is an integral part of the constitutive activation of WNT/β-catenin or PI3K/AKT signalling and their expression patterns were correlated with the clinical, pathological and molecular characteristics of the different subgroups of colorectal carcinoma. Increased nuclear β-catenin expression, an indicator of activated WNT signalling, is associated with MSS and the pathological features of CIN type tumours and inversely associated with the pathological and molecular features of MSI+ and CIMP+ tumours. In all forms of sporadic colorectal carcinoma, nuclear β-catenin expression was not an indicator of overall survival. PTEN was not associated with any particular subgroup of sporadic colorectal carcinoma, but decreased cytoplasmic expression was indicative of overall worse outcome, especially in MSS or CIN type tumours. While the identification of nuclear β-catenin in sporadic colorectal carcinomas is not a satisfactory prognostic marker, the immunohistochemical detection of absent PTEN expression may prove useful in identifying poor outcome in individuals with sporadic MSS colorectal carcinoma.
34

Genetic and epidemiological studies of hereditary colorectal cancer /

Cederquist, Kristina, January 2005 (has links)
Diss. (sammanfattning) Umeå : Univ., 2005. / Härtill 5 uppsatser.
35

Colorectal carcinoma and markers of biological activity / Colorectal carcinoma and markers of biological activity

Lipská, Ludmila January 2006 (has links)
The author deals with two groups of patients diagnosed with colorectal cancer and compared patients with this diagnosis are treated and monitored a second group in which this newly diagnosed disease.
36

Sledování biologické aktivity kolorektálního karcinomu metodou real-time PCR / Assessment of Biological Activity of Colorectal Carcinoma using RT REAL-TIME PCR

Pešta, Martin January 2006 (has links)
The author in his doctoral thesis, proposed primers and conditions optimized design Quantitative PCR for determining the gene expression of MMP-7, TIMP-1, MMP-2 and TIMP- second Revealed the presence of gene expression of GAPDH TIMP-1 and TIMP-2 in cancer line HT-29 SW480 and SW620. Noted the high level expression of MMP-7 in line HT-29th Expression of the 2-3 orders of magnitude higher than the lines SW480 and SW620. MRNA expression of MMP-2 in line HT-29 noticed. MRNA expression of MMP-2 by the detected lines SW480 and SW620. He found that determining absolute and relative expression in tumor lines is ekvivalentní. significantly higher mRNA expression of MMP-7, TIMP-1, MMP-2 and TIMP-2 in tumor tissue compared to normal tissue. It can be used in therapy. Noticed the presence of correlation of gene expression MMP-7, TIMP-1, MMP-2 and TIMP-2 with survival and DFI. He showed that a higher stage cancer correlated with a higher median momery MMP-2/TIMP-2. 7, Noticed the difference in gene expression between TS, TP and DPD in control and tumor tissue. Scored marginally significant increase in TS expression in colon tumors compared to tumors rectosigmoid and rectum. This finding can be used in treatment decisions. scored marginally significant correlation between the expression of TS and DPD. This finding can be...
37

Stanovení nádorové mRNA u kolorektálního karcinomu jako screeningové a prognostické metody / Determination of tumor mRNA in colorectal cancer as screening and forecasting methods

Rupert, Karel January 2007 (has links)
The level of MMP-7, TIMP-1 and MMP-2 mRNA expression was significantly higher in the tumour tissue of colorectal carcinoma than in normal colorectal tissue. It could be possible to inhibit matrix metalloproteinases activity using appropriate antibodies, which could have therapeutic effect on tumour tissue and its vicinity. Some of the preparations are being tested (Bay 12-9566 /Bayer/, BB94 /British Biotechnology/). We have not proved correlation between expression of these genes and disease stage and diagnosis. We have succeeded to prove that if the surgical principles for colon resection performed due to colorectal carcinoma are observed, the resection line does not show any signs of the presence of tumour cells - mRNA for CEA is not present. The level of mRNA for TIMP-1 is present in the resection line at lower levels than in tumour tissue, and this is due to the role that TIMP- 1 plays in the colon. Its level increases not only in all tumour diseases, but also in inflammatory diseases of the colon. The question whether the expression of mRNA for TIMP-1 is also increased outside the resection line and therefore it is a reaction of the colon as an organ will be subject to further research, as will be a potential comparison with samples of colon unaffected by tumour or inflammation. Although the...
38

Distribution of carbonic anhydrase IX, MN/CA IX, in normal and neoplastic gastrointestinal and hepatobiliary tissues:its potential value as a new biomarker and comparison of its expression with that of isoenzymes I, II, IV, V, and VI

Saarnio, J. (Juha) 03 October 2000 (has links)
Abstract The carbonic anhydrase (CA) gene family contains eleven active members, the basic physiological functions of which are linked to the interconversion of carbon dioxide and bicarbonate (CO2 + H2O ⇔ H+ + HCO3⇔ H2CO3-). They participate in a variety of physiological processes that involve pH regulation, CO2 and HCO3- transport and water and electrolyte balance, and some new functions have also been suggested recently. A novel tumour-associated antigen, MN, containing a CA-domain and named MN/CA IX, has been found to promote cell proliferation when transfected into NIH3T3 cells and has also been shown to be a potential biomarker for neoplasia in the uterine cervix. The present study examines the expression of MN/CA IX in the normal alimentary tract by immunohistochemistry and compares it with the expression of cytoplasmic CA I, CA II, apical plasma membrane associated CA IV and secretory CA VI. The distribution of mitochondrial CA V is examined by immunohistochemistry and Western blotting. The value of MN/CA IX as a potential biomarker of gastrointestinal tumours is assessed in a series of colorectal and hepatobiliary neoplasms. A positive immunoreaction for MN/CA IX was detected in the basolateral plasma membrane of the gastric, intestinal and biliary epithelium, but was confined to the proliferating cryptal enterocytes in the human gut, suggesting a role in cellular proliferation. In colorectal tumours, MN/CA IX immunoreaction was also located in the proliferative zone, indicating that it could be a useful marker of cellular proliferation. In the case of hepatobiliary tumours a positive signal was mainly associated with tumours of biliary epithelial parentage. These results demonstrate that MN/CA IX has a unique expression pattern in the alimentary tract relative to other CAs. Its localization and enzymatic properties suggest that it may have a dual function in the gastrointestinal epithelium. Through its CA activity it could participate in the regulation of carbon dioxide/bicarbonate homeostasis, while its localization to the basolateral surfaces of proliferating cryptal enterocytes suggests that it may serve as a ligand or receptor for one or more other proteins that regulate intercellular communication and/or cell proliferation. MN/CA IX may also serve as a new biomarker of gastrointestinal tumours.
39

A bioinformatics meta-analysis of differentially expressed genes in colorectal cancer

Chan, Simon Kit 05 1900 (has links)
BACKGROUND: Elucidation of candidate colorectal cancer biomarkers often begins by comparing the expression profiles of cancerous and normal tissue by performing high throughput gene expression profiling. While many such studies have been performed, the resulting lists of differentially expressed genes tend to be inconsistent with each other, suggesting that there are some false positives and negatives. One logical solution to this problem is to determine the intersection of the lists of differentially expressed genes from independent studies. It is expected that genes that are biologically relevant to cancer tumorigenesis will be reported most often, while sporadically reported genes are due to the inherent biases and limitations of each of the profiling platforms used. However, the statistical significance of the observed intersection among many independent studies is usually not considered. PURPOSE: To address these issues, we developed a computational meta-analysis method that ranked differentially expressed genes based on the following criteria, which are presented in order of importance: the amount of intersection among studies, total tissue sample sizes, and average fold change in expression. We applied this meta-analysis method to 25 independent colorectal cancer profiling studies that compared cancer versus normal, adenoma versus normal, and cancer versus adenoma tissues. RESULTS: We observed that some genes were consistently reported as differentially expressed with a statistically significant frequency (P <.0001) in the cancer versus normal and adenoma versus normal comparisons, but not in the cancer versus adenoma comparison. We performed a review of some of the high ranking candidates and determined that some have previously been shown to have diagnostic and/or prognostic utility in colorectal cancer. More interestingly, the meta-analysis method also identified genes that had yet to be tested and validated as biomarkers. Thus, these candidates are currently being validated at the protein level on colorectal tissue microarrays. CONCLUSION: Our meta-analysis method identified genes that were consistently reported as differentially expressed. Besides identifying new biomarker candidates, our meta-analysis method also provides another filter to remove false positive genes from further consideration. In conclusion, the genes presented here will aid in the identification of highly sensitive and specific biomarkers in colorectal cancer. / Science, Faculty of / Graduate
40

Determinants of survival and metastasis free survival in human colorectal cancer : tp53, p33'I'N'G'1'b and thymidylate synthase

Ahmed, Ihab Abdel-Rahim Mohamed January 2003 (has links)
No description available.

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