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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.
1

A molecular analysis of genes involved in the cell cycle in southern African blacks with hepatocellular carcinoma

Martins, Carla Suzana Pinto 22 May 2014 (has links)
Hepatocellular carcinoma (HCC) is a leading cause of death in both Africa and Asia. It is multifactorial in aetiology and complex in its pathogenesis. Genes that might affect tumour progression, invasion, and metastasis are good candidates to investigate in attempting to understand the transformation process. The p53, RBI, BRCA1, BRCA2, WT1 and Ecadherin genes were analysed for allelic imbalance/loss of heterozygosity (LOH), polymorphisms, and mutations. Tumour and non-tumorous liver tissue from 25 southern African blacks were examined, using polymerase chain reaction restriction fragment length polymorphisms (PCR-RFLP) and PCR-single stranded conformational polymorphisms (SSCP), sequencing, and Southern blotting techniques. Allele frequencies for polymorphisms at the WEI, D13S137, D13S120, D13S127, D17S855, D16S301, and D16S260 loci were determined in 20 random African blacks using microsatellite analysis to determine allele frequencies, polymorphism information content (PIC) and diversity (H) values. To our knowledge this has not been done previously for these loci in this population. The chromosomal region l i p 13, containing the VV77 gene, and the gene itself has been reported to be deleted in 4.5% of HCCs. LOH was detected at the WT1 locus for 1/13 HCCs (8%) in this study. The RBI gene has been described to be mutated in 32.4% (China), 33.3% (Korea), 29% and 50% tJapan), and 27% (Australia), of advanced stage HCCs. In our study LOH at this locus was found in 3/19 HCCs (16%). Our finding of LOH at the BRCA2 locus in 2/20 HCCs (10%) supports the previously proposed notion that BRCA2 may function as a tumour suppressor gene in a hormone-related pathway in the liver, and that it may in some way be involved in HCC. No conclusive findings were made for any o f the other loci. Microsatellite instability was detected in 3/22 (14%) individuals. We propose that microsatellite/genomic instability may play a role in a subset of HCCs only. O f this population, 27 % had the specific p53 codon 249 AGG-AGT mutation in some tumour and non-tumorous liver. This was expected as the great majority of the individuals were from Mozambique, a country where heavy aflatoxin exposure is prevalent. All the loci examined in the allele frequency studies proved to be highly informative, showing high PIC and ED values, and should therefore be useful in population studies.
2

Genetic alterations in hepatocellular carcinoma. / CUHK electronic theses & dissertations collection

January 1998 (has links)
by Hiu-Ming Li. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references (p. 176-198). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.
3

Treatment of inoperable hepatocellular carcinoma: from systemic to regional, from conventional to novel.

January 1995 (has links)
by Wai-Tong Leung. / Thesis (M.D.)--Chinese University of Hong Kong, 1995. / Includes bibliographical references (leaves 282-315). / Title Page --- p.i / Dedication --- p.ii / Table of Contents --- p.iii / Precis to the thesis --- p.7 / Glossary of abbreviation used in the thesis --- p.20 / List of Figures and Pictures --- p.22 / List of Tables --- p.26 / Acknowledgments --- p.30 / Statement of Originality --- p.32 / Chapter PART ONE --- Introduction / Chapter Chapter 1 --- Background for Hepatocellular Carcinoma / Chapter 1. --- History --- p.33 / Chapter 2. --- "Epidemiology - World wide, China,Hong Kong" --- p.36 / Chapter 3. --- Pathology --- p.55 / Chapter 4. --- Aetiology --- p.62 / Chapter 5. --- Clinical Manifestation and Diagnosis --- p.68 / Chapter 6. --- Natural History --- p.74 / Chapter 7. --- Conventional Treatment --- p.76 / Chapter 8. --- Prognosis --- p.85 / Chapter Chapter 2 --- Hepatocellular Carcinoma in Hong Kong / Chapter 1. --- Clinical Study of 1119 cases of Hepatocellular Carcinoma --- p.88 / Chapter PART TWO --- Conventional Treatment for Hepatocellular Carcinoma / Chapter Chapter 3 --- Chemotherapy for Hepatocellular Carcinoma / Chapter 1. --- Review of the Literature in Systemic Chemotherapy --- p.108 / Chapter 2. --- Phase II Trials of Systemic Chemotherapy --- p.114 / Chapter a. --- VP16-213 --- p.115 / Chapter b. --- Low Dose 4'-Epidoxorubicin --- p.116 / Chapter c. --- High Dose 4'-Epidoxorubicin --- p.117 / Chapter d. --- 5_FU and High Dose Folinic Acid --- p.119 / Chapter e. --- High Dose Ifosfamide --- p.122 / Chapter 3. --- Review of the Literature in Intra-Arterial Chemotherapy --- p.125 / Chapter 4. --- Intra-Arterial Chemotherapy Trial Performed in PWH --- p.131 / Chapter a. --- An Early Phase II Trial on Treatment of Inoperable Hepatocellular Carcinoma by Intrahepatic Arterial Chemotherapy with Lipiodol and 4'-Epidoxorubicin --- p.131 / Chapter b. --- "Phase II Trial of Treatment of Inoperable Hepatocellular Carcinoma by Intra-Arterial Lipiodol and High Dose 4'-Epidoxorubicin, a Comparison with Intravenous 4'-Epidoxorubicin" --- p.137 / Chapter PART THREE --- Novel Treatment for Hepatocellular Carcinoma / Chapter Chapter 4 --- Selective Internal Radiation Treatment for Hepatocellular Carcinoma / Chapter 1. --- Review of the Literature in Radiotherapy for Liver Tumours --- p.145 / Chapter 2. --- Selective Internal Radiation with 131Iodine-Lipiodol in HCC / Chapter a. --- Background and Review of the Literature --- p.151 / Chapter b. --- Physical Aspects of 131Iodine-Lipiodol --- p.154 / Chapter c. --- Bio-distribution of 131I-L in one HCC Patient --- p.156 / Chapter d. --- Clinical Study on the Use of131I-Lipiodol in the Treatment of Inoperable HCC --- p.168 / Chapter 3. --- Selective Internal Radiation with 90Yttrium-Microspheres in HCC / Chapter a. --- Background and Review of the Literature --- p.182 / Chapter b. --- Physical Aspects of 90Yttrium-Microspheres --- p.187 / Chapter c. --- Treatment of Inoperable Hepatocellular Carcinoma with Intrahepatic-Arterial 90Yttrium Microspheres - An Early Phase II Study --- p.195 / Chapter d. --- Treatment of Inoperable Hepatocellular Carcinoma with Intrahepatic-arterial 90Yttrium Microspheres through Hepatic Angiography --- p.214 / Chapter 4. --- Selection of Patients for 90Yttrium -Microspheres Treatment --- p.230 / Chapter a. --- Diagnostic Scintigraphy with Hepatic Intra-Arterial Technetium-99m Macroaggregated Albumin in the Determination of Tumour to Non-Tumour Uptake Ratio in Hepatocellular Carcinoma --- p.230 / Chapter b. --- Measuring Lung Shunting in Hepatocellular Carcinoma with Intrahepatic-Arterial Technetium-99m Macroaggregated Albumin Scan --- p.245 / Chapter c. --- Correlation of Tumour Vascularity Grading by Selective Hepatic Angiography with T/N Ratio from Tc-MAA Scanin Hepatocellular Carcinoma --- p.260 / Chapter d. --- Pulmonary Complications from 90Yttrium-Microspheres Treatment --- p.266 / Conclusion of the Thesis --- p.280 / References to Chapter1 --- p.282 / References to Chapter2 --- p.296 / References to Chapter3 --- p.297 / References to Chapter4 --- p.308 / Appendix: / Chapter 1. --- Recommendations for Grading of Acute and Subacute Toxicityin Cancer Treatment --- p.316 / Chapter 2. --- Recommendations for Grading of Response Criteria --- p.318 / Selected Publications by the Author Relevant to the Thesis --- p.319
4

The Prognostic Role and Expression of the Ubiquitin Ligase Subunits Skp2 and Cks1 in Hepatocellular Carcinoma

Huang, Chinh-wen 15 August 2007 (has links)
The incidence of hepatocellular carcinoma (HCC) is high in Taiwan, because Taiwan is one of HBV-endemic areas. Moreover, HCCs are the 2nd most common cause of death caused by malignancies in Taiwan. Early detection of HCC can improve the survival rate because the stage is one of important prognostic factors. Alpha-fetoprotein (AFP) is the most important tumor marker for diagnosis of HCC and surveillance of treatment. However, the sensitivity, the specificity and positive predictive value of AFP are not very satisfactory. The cell cycle inhibitor p27kip1 is known as a potential prognostic marker for HCC. Decreased expression of cell cycle inhibitor p27kip1 is associated with poor prognosis in HCC. The decreased expression of p27kip1 results from increased ubiquitin-proteosome degradation. S-phase kinase associated protein (Skp2) and cyclin-dependent kinase subunit 1 (Cks1) are the subunits of the ubiquitin ligases responsible for the ubiquitin-proteosome degradation of p27kip1. The increased expression of Skp2 and Cks1 were found in many kinds of human cancers. However, there is no report about the relationship between Cks1, Skp2 and p27kip1 expression in hepatocellular carcinoma. In the present study, we investigated the expression of Cks1, Skp2 and p27kip1 and their prognostic roles in hepatocellular carcinoma. We used highly specific antibodies in immunohistochemistry to examine the expressions of Cks1, Skp2, and p27kip1 on paraffin-embedded tissue section from 75 patients with hepatocellular carcinoma. Meanwhile, we also analyzed the clinical significance of these three proteins with the various clinicopathological factors and follow-up data. Well-differentiated HCCs tended to express higher level of p27kip1 (55.6%), and lower levels of Skp2 (66.7%) and Cks1 (77.8%). Poorly differentiated HCCs tended to express lower level of p27kip1 (64.3%). The expression of Cks1 was significantly associated with the expression of Skp2 (P=0.000). In contrast, there were no inverse relationships between the expression of p27kip1 and the expressions of Skp2 and Cks1 in the present study. The expressions of p27kip1, Skp2, and Cks1 were significantly associated with disease stage (AJCC TNM stage system and CLIP scoring system). Moreover, there were significant associations between overall survival rates and the expressions of Skp2 and Cks1 (P = 0.036 and 0.015, respectively). Patients with higher expression of Skp2 and Cks1 had worse survival rates. This is the first report of the expression and prognostic role of Cks1 in HCC. Higher expression of Skp2 and Cks1 were significantly associated with advanced stage and poor prognosis. Thus, both Skp2 and Cks1 may be considered as potential novel prognostic markers providing more accurate prediction of prognosis combined with AFP and therapeutic targets in HCCs.
5

The IGF-axis in liver disease : modulation of expression by histone deacetylase inhibitors /

Gray, Steven, January 1900 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst. / Härtill 6 uppsatser.
6

Molecular pathology of rat hepatic nodules

Roomi, Md. Waheed January 1987 (has links)
The aim of the present study was to characterize the phenomenon of resistance in putative preneoplastic hepatocyte nodules. These hyperplastic nodules are generated during the development of liver cancer in response to chemical carcinogens, and comprise a population of cells from which hepatocellular carcinoma can develop. As hepatocyte nodules grow in an environment that is otherwise toxic they possess a resistant phenotype. To understand this resistance phenomenon at the biochemical level, several phase I and II drug-metabolizing enzymes in the nodules were examined. Initial experiments were carried out in rats with nodules produced by initiation with diethylnitrosamine, followed by selection with 2-acetylaminofluorene and carbon tetrachloride. These nodules showed a large decrease in phase I enzymes and enzymic activities, such as the cytochromes P-450, cytochrome b[5], total microsomal haem, aminopyrine N-demethylase and ethoxyresorufin 0-deethylase, but glutathione and the phase II enzymes, namely, glutathione S-transferase, UDP-glucuronyl transferase, DT-diaphorase and gamma-glutamyltransferase were significantly increased. The pattern of changes of these drug-metabolizing enzymes of the nodules was similar when the nodules were produced by different initiation-promotion treatments, including diethylnitrosamine plus a choline/methionine-deficient diet, 2-acetamidofluorene plus phenobarbi-tone, or diethylnitrosamine plus orotic acid. In addition, the resistance phenotype was maintained when these nodules were transferred into the spleen of a rat not exposed to chemical carcinogens, and allowed to grow for several months, thus indicating that the newly acquired biochemical pattern in the nodules had become constitutive. Unlike the hepatic nodules generated by previous initiation-pro-motion treatments, nodules generated by the hypolipidemic agent, ciprofibrate, exhibited only a decrease in phase I components of the drug-metabolizing enzymes, with no increase in the phase II components. Similarly, hyperplastic nodules in liver mouse showed a decrease in phase I components, but no increase in phase II components. In addition to cytochrome P-450 and cytochrome b5, the total haem and two other haem containing proteins, namely, catalase and tryptophan 2,3-dioxygenase were also decreased in the nodules. A deficiency in hepatic iron, and a decrease in the activity of delta-ALA-synthetase, the first rate limiting enzyme in haem synthesis, were also apparent. Characterization of the phase II components revealed the presence of a new glutathione-S-transferase polypeptide, which has been shown to be identical to a placental form of the transferase. This polypeptide, although present to a minimal extent, or absent, in normal rat liver, is present in normal male mouse liver. Administration of lead nitrate to rats induces a biochemical pattern in the liver similar to that seen in the hepatocyte nodules, including a decrease of phase I components and an increase in phase II components of the drug-metabolizing enzymes, and the induction of the novel glutathione S-transferase. Further studies with lead nitrate may yield new insights into the mechanisms of production of the biochemical changes induced in the nodules, as this agent generates the same changes within 30 hours. Furthermore, the lead nitrate-induced changes in phase I and phase II enzymes are reversible, while the changes seen in the hyperplastic nodules are not. Thus this study has characterized one pattern of biochemical changes exhibited by the resistant phenotype of hyperplastic hepatic nodules, and a model system has been developed which induces the same changes, more rapidly and in a reversible fashion. One of the important questions yet to be answered however is the biological significance of the resistant phenotype in cancer development. Is the acquisition of resistance only important in expanding the initiated cell population to generate nodules or does it also have a more direct role in the progression of nodules to cancer? This is highly relevant to the clarification of the carcinogenic process in the liver and perhaps in other organs as well.
7

Gas embolization as a minimally invasive therapy for the treatment of hepatocellular carcinoma

January 2020 (has links)
archives@tulane.edu / Hepatocellular carcinoma is an intractable cancer with a high mortality rate. Transarterial chemoembolization, a non-curative method, is the first line therapy for intermediate stage patients. This effectively extends patient survival but requires a complicated intraarterial catheterization procedure and is poorly suited to repeated administration. Gas embolization has been proposed as a fast, easily administered, more spatially selective, and less invasive alternative. This process involves generating emboli in situ using acoustic droplet vaporization, the noninvasive focused ultrasound-mediated conversion of intravenously administered perfluorocarbon microdroplets into microbubbles. The work presented in this dissertation provides the first evidence of the feasibility and efficacy of gas embolization in vivo. Following confirmation of the cessation of tumor growth after treatment in a preliminary study, two additional preclinical studies were conducted. Varying treatment parameters and the use of systemic chemotherapy alongside gas embolization resulted in consistent, substantial tumor regression and a suppression of tumor recurrence following the cessation of treatment. Subsequent steps toward optimizing the treatment method, primarily intended to mitigate off-target tissue damage and to maximize the uniformity of treatment coverage across a lesion, involved the implementation of two specialized imaging modes for tumor detection and treatment planning and the development of an ultrasound-guided treatment method. Finally, retention of the lipid droplet shell upon vaporization was investigated in the context of selective targeting for localized drug delivery. The dissertation closes with a discussion of the implications of the presented work and proposed future studies. / 1 / Jonah Harmon
8

Full genome analysis and functional characterization of mutants of hepatitis B virus isolates from southern African blacks

Kimbi, Gerald Chiafiinii 11 August 2008 (has links)
Abstract will not load on to DSpace
9

Therapeutic Efficacy of Celecoxib for Orthotopic Novikoff Hepatoma

Chu, Tian-huei 26 August 2009 (has links)
Hepatocellular carcinoma (HCC) is one of deadliest cancers worldwide and ranking the third among all cancer-related mortalities. Current effective therapeutic approaches for HCC include surgical resection and trans-arterial embolization (TAE). Chemotherapy remains largely ineffective, and most popular used agents are epirubicin, doxorubicin, cisplatin and 5-FU. Besides, these chemotherapic drugs had potential serious side-effects such as low blood count, hair loss, vomiting, and they rarely present good anti-HCC effect in clinical practice. Our previous studies found that epirubicin injection attenuated the tumor burden of orthotopic Novikoff hepatoma, but caused serious side effects to hosts including reduction in spleen weight, white count, and body weight and high GOT level. Therefore, we aimed to evaluate possible alternative treatment such as COX-2 inhibitor for HCC. Celecoxib is a highly selective COX-2 inhibitor and less toxic than the traditional non-selective NSAIDs. Celecoxib showed relatively low cytotoxicity in Novikoff N1-S1 hepatoma cells and Clone 9 normal hepatocytes with an IC50 of up to 100 microM. Expression analysis revealed that COX-2 expression is very low in N1-S1 cells at protein and mRNA levels. Thus, N1-S1 is a kind of hepatoma cell line with low COX-II level. Interestingly, celecoxib upregulated PTEN expression and decreased AKT phosphorylation in vitro by COX-2 independent pathway, and then oral administration of celecoxib (30 mg/kg) for 7 days showed tendency of tumor suppression of Novikoff hepatoma in rats revealed by ultrasound and computed tomography (CT) scan. Histological analysis revealed that CD31-positive neo-vascularization¡BKi-67-positive cell-proliferation and FOXP3-positive regulatory T cells were found to reduce in celecoxib-treated rats, and then TUNEL-positive apoptotic cells were found to increase in celecoxib-treated rats. Besides, celecoxib-treated rats exhibited no significant side effect. Therefore, oral celecoxib may be a suitable chose of adjuvant therapy in combination with epirubicin or other chemotherapeutic agents for the treatment of HCC.
10

Changes to the host cell proteome induced by expression of hepatitis C virus NS3/4A open reading frames

Patterson, Aileen 13 January 2014 (has links)
Hepatitis C virus (HCV) infects an estimated 200,000 people in Canada, and is the leading cause of liver transplants in North America. Viral infection usually leads to chronic infection, and complications include liver fibrosis, steatosis and hepatocellular carcinoma (HCC). The HCV non-structural proteins 3 and 4A (NS3/4A), is a multifunctional protein complex with roles in RNA replication and polyprotein processing. Additionally, the NS3 protease has been shown to induce advanced cellular transformation in vivo and tumour formation in nude mice. However, the mechanism by which transformation occurs remains unknown. The objective of this study was to determine if the naturally occurring NS3/4A protein complex, rather than the NS3 protease domain on its own, could also induce cellular transformation and to determine the changes that NS3/4A expression had on the host cell proteome.

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