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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.
511

Rôle de la consommation d'Anti-inflammatoires Non Stéroïdiens (AINS) dans la survenue du cancer de la prostate, du sein, et colorectal en France / Role of NSAIDs' Use in the Occurrence of Prostate, Breast and Colorectal Cancer in France

Doat, Solène 21 December 2017 (has links)
Contexte – Les cancers de la prostate, du sein, et colorectaux sont parmi les cancers les plus fréquents dans les pays développés, et, même si plusieurs facteurs de risque sont aujourd’hui bien établis pour ces cancers, leur étiologie reste encore largement à expliquer. L’inflammation chronique est fortement suspectée de jouer un rôle dans la survenue de ces cancers et la présence, dans les tissus tumoraux, d’infiltrats inflammatoires localisés pouvant être considérés comme des lésions précancéreuses, contribue à renforcer l’hypothèse d’un lien possible entre inflammation chronique et cancers. Dans ce contexte, de nombreuses études épidémiologiques se sont intéressées au rôle des Anti-Inflammatoires Non Stéroïdiens (AINS) dans les cancers. En effet, les médicaments ayant des propriétés anti-inflammatoires comme les AINS, dont l’aspirine, et les anti-inflammatoires inhibiteurs sélectifs de la cyclo-oxygénase 2 (COX-2), pourraient diminuer le risque de survenue de ces cancers.Objectifs – L’objectif général de cette thèse a été d’étudier le rôle de la consommation d’AINS, dont l’aspirine, les AINS usuels et les inhibiteurs sélectifs de la COX-2 dans la survenue des cancers de la prostate, du sein et colorectaux.Population et méthodes – Ce travail s’est appuyé sur les données de l’Echantillon Généraliste des Bénéficiaires (EGB) de l’Assurance Maladie pour les trois cancers d’intérêt et sur les données d’une étude cas-témoins réalisée en population générale dans le département de l’Hérault (EPICAP) pour le cancer de la prostate. Pour les données de l’EGB, une cohorte fixe de 426 410 personnes présentes au 1er janvier 2007 a permis d’identifier les cas incidents entre 2008 et 2012 à partir de différents algorithmes. L’exposition aux AINS a été identifiée à partir du 1er janvier 2005 jusqu’à la date de fin d’observation : date de survenue du cancer, date de décès ou date de censure fixée au 31 décembre 2012. Un temps de latence d’au moins un an a été défini entre l’exposition aux AINS et la survenue du cancer d’intérêt. Pour les données d’EPICAP, 819 cas incidents de cancer de la prostate et 879 témoins de population générale, de même âge en moyenne que les cas, ont été interrogés en face-à-face, à l’aide d’un questionnaire standardisé, notamment sur leur consommation d’AINS.Résultats – A partir de la cohorte issue de l’EGB, des résultats préliminaires montraient une augmentation du risque de cancer de la prostate (RR=1,30 [1,17-1,46]) et du sein (RR=1,29 [1,14-1,46]) chez les patients exposés aux AINS et une absence d’association pour les cancers colorectaux (RR=0,92 [0,82-1,05]). En revanche, une association négative était observée pour les cancers de la prostate (RR=0,85 [0,74-0,96]) et colorectaux (RR=0,77 [0,66-0,90]) lorsque le temps de latence considéré était de six ans. L’étude EPICAP a montré que la consommation d’AINS était associée négativement au cancer de la prostate (OR=0,77 [0,61-0,98]). Cette association était plus prononcée pour une fréquence de consommation quotidienne (OR=0,75 [0,33-0,92]) ou d’une consommation pluriquotidienne (OR=0,38 [0,18-0,79]), et pour une durée entre 5 à 10 ans (OR=0,55 [0,33-0,92]). L’association était renforcée pour une molécule ayant une activité anti-COX-2 préférentielle (OR=0,48 [0,28-0,79]). Enfin, une association négative était également observée pour les cancers de la prostate de haut grade (Gleason score =7 (4+3) ou GS>7) avec un OR de 0,62 [0,41-0,95].Conclusion – L’ensemble de ce travail de thèse a montré que la consommation d’AINS semblait être associée négativement à la survenue du cancer de la prostate et aux cancers colorectaux. Pour le cancer de la prostate cette thèse s’est appuyée sur deux bases de données et deux méthodologies différentes, permettant d’appréhender les limites et les forces de chacune. / Background – Prostate, breast, and colorectal cancers are among the most common cancers in developed countries. Many risk factors have been identified over the years but could explain only a part of the new cases. Chronic inflammation is highly suspected to play a role in the carcinogenesis of those cancers and the presence of inflammatory infiltrate in tumoral tissue, considered as precancerous lesions, reinforced this hypothesis. In this context, several epidemiological studies have investigated the potential role of Non-steroidal anti-inflammatory drugs (NSAIDs) in cancer occurrence. Indeed, NSAIDs such as aspirin and non-aspirin NSAIDS including selective inhibitors of cyclo-oxygenase 2 (COX-2) may decrease the incidence of those cancers.Objectives – The main objective of the thesis was to investigate the role of NSAIDs use including aspirin, non-aspirin NSAIDs and selective inhibitors of COX-2 in the occurrence of prostate, breast and colorectal cancers.Population and methods – This work was based on the General Sample of health insurance Beneficiaries (EGB) for the three localizations of cancer and on the data of a population-based case-control study carried out in the département of Herault (EPICAP) for prostate cancer. In the EGB study, a cohort of 426 410 persons present in the database in January 1st, 2007 allowed to identify incident cases between 2008 and 2012 based on different algorithms. Exposure to NSAIDs was determined from January 1st, 2005 until the end of the follow up defined as either cancer incident date, date of death, or censure date fixed as December 31st, 2012. A latency of at least one year between the beginning of exposure to NSAIDs and the cancer occurrence was taken into account. For the EPICAP study, 819 incident prostate cancer cases and 879 population-based controls, frequently matched by age to the cases, were face-to-face interviewed using a standardized questionnaire, specifically on their NSAIDs use.Results – From the EGB cohort, preliminary results showed a positive association between all NSAIDs use and prostate or breast cancer occurrence (RR=1,30 [1,17-1,46], RR=1,29 [1,14-1,46], respectively), while no association was found with colorectal cancer occurrence (RR=0,92 [0,82-1,05]). These associations became negative associations when a latency of six years was taken into account in prostate and colorectal cancer (RR=0,85[0,74-0,96], RR=0,77 [0,66-0,90], respectively). In the EPICAP study, NSAIDs use was negatively associated with prostate cancer (OR=0,77 [0,61-0,98]). This association was more pronounced with daily intake (OR=0,75 [0,33-0,92]) or more than once a day (OR=0,38 [0,18-0,79]), and for a duration of five to ten years (OR=0,55 [0,33-0,92]). The negative association was reinforced for preferential anti-COX-2 NSAIDs (OR=0,48 [0,28-0,79]), and for patient with high grade prostate cancer (Gleason score, GS=7 (4+3) or GS>7 : OR=0,62 [0,41-0,95]).Conclusion – This work showed that NSAIDs use was negatively to prostate and colorectal cancer occurrence. For prostate cancer, this thesis was based on two different databases (a medical and administrative database and a case-control study) and used two different methodologies, allowing comparison about strengths and limits of both.
512

Nucleotide sequence variation and expression levels of TP53 in cancers of the upper gastro-intestinal tract

Barnard, Desire 03 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2004. / ENGLISH ABSTRACT: The work presented in this thesis deals with the association between cancers of the upper gastro-intestinal tract and the tumor suppressor gene, TP53, and can be divided into three parts: (i) the analysis of the mutational spectrum of TP53 with respect to laryngeal cancer, (ii) the analysis of the mutational spectrum of TP53 with respect to esophageal cancer and (iii) the analysis of TP53 transcriptional levels in esophageal cancer. Laryngeal cancer (LC) is the 6th most common cancer in the world and the 2nd most common respiratory cancer, with approximately 500 000 new cases per annum detected worldwide. Over the last few years, LC has become increasingly prevalent within the Coloured Community of the Western Cape. The mechanisms of tumorigenesis in LC remain unknown, although smoking and alcohol consumption are considered to be major risk factors. Mutations within the gene TP53 have been strongly implicated as playing a role in cancer development, as they are frequently found in several cancer types. We therefore screened exons 5 - 8 of TP53 for mutations in DNA from tumor biopsies (n=44) and blood samples (n=42) from Coloured LC patients, using polymerase chain reaction - single strand conformation polymorphism (PCR-SSCP) analysis and direct sequencing. Blood samples from a healthy, matched control group (n=40) were included in the study as controls. Significant correlations were found between the occurrence of LC and age and smoking, whereas daily meat consumption was a possible protective factor. In tumor-derived samples, mutations were found in 3 of the exons under investigation, representing 25% of the samples. The mutations were unique to the tumor biopsies, indicating a somatic origin for mutations. The data confirms that the region between codons 175 and 273 of TP53 is a mutational hotspot for cancers in general. This study reports 6 novel mutations within this same region. Esophageal cancer (EC) has a very high incidence in South Africa, relative to the rest of the world, and is particularly common amongst the Black Transkei population. The goal of this study was to determine whether there are differences in the TP53 mutational pattern observed in the Coloured Western Cape community as compared to that observed in the Black Transkei community. This required the analysis of the molecular structure of TP53, specifically exons 5 - 8, in a group of Coloured EC patients (n=44) treated at Tygerberg Hospital, Cape Town, South Africa. DNA obtained from tumor biopsies and blood (from patients) as well as from apparently healthy surrounding tissue was screened via PCR-SSCP and direct sequencing analysis. Only 4 nucleotide changes were observed from a total of 124 sequences obtained, of which two were novel to esophageal squamous cell carcinoma. These 4 nucleotide alterations were found only within the tumor biopsy sample set, representing 9% of the tumors investigated. This study revealed that the mutational spectrum of TP53 within the Coloured population of the Western Cape greatly differs from that of the Black community of the Transkei. This suggests that a different set of etiological factors are involved in the tumorigenic process for each of these distinct geographical communities, which is the subject of an epidemiological study undertaken by the MRC. The final part of this thesis deals with the quantification and comparison of TP53 transcription levels in esophageal cancer tumor tissue to the TP53 levels in healthy esophageal tissue obtained from patients from a unique geographical and ethnic background. The cohort used in this study consisted of Coloured patients (n=2) treated at Tygerberg Hospital. The LightCycler system was implemented in order to try to accurately quantify TP53 mRNA levels. Unfortunately, the desired results were unattainable due to unforeseen difficulties encountered during the study. These difficulties included the insufficient preservation of samples for RNA based studies. Several recommendations were made concerning future similar studies, including an improved planning strategy as well as the employment of an RNA stabilizing agent. Additionally, a few important contributions were made through this study, including the design and optimization of TP53 primers specifically intended for future RNA studies. These primers would enable the identification of the presence of TP53 RNA species as well as the absence of DNA contamination in a single PCR amplification step. Other contributions include the development of a well-optimized RNA extraction method for the extraction of RNA from tough tissues (such as the human esophageal tissue used in this study). This method makes the extraction of large quantities of RNA from small amounts of tough tissue types possible. In conclusion, this study has made a significant contribution to the field of cancer research, by shedding light on the TP53 mutational spectrum with regards to laryngeal as well as esophageal cancer in a population unique to the Western Cape. The first part of this thesis has been published in Cancer Genetics and Cytogenetics (Barnard, D., K. Lehmann, E.G. Haal, P.O. van Heiden, and l.C. Victor. 2003. The spectrum of mutations in TP53 in laryngeal cancer patients from a high-incidence population shows similarities to many of the known mutational hotspots. Cancer Genetics and Cytogenetics 145:126-132), of which a copy can be found in Appendix I. This work has also been presented (by D. Barnard) at an international conference entitled "Cancer of the Esophagus and Gastric Cardia: From Gene to Cure", held in Amsterdam, the Netherlands during the period 13 - 15 December 2002. / AFRIKAANSE OPSOMMING: Die werk wat in hierdie tesis voorgelê word handel oor die assosiasie tussen kankers van die boonste gastrointestinale weg en die tumor suppressor geen, TP53, en kan in 3 dele gedeel word, (i) die analise van die mutasiespektrum van TP53 in laringiale kanker (LK), (ii) die analise van die mutasiespektrum van TP53 in slukderm kanker (SK) en (iii) die analise van die transkripsievlakke van TP53 in SK. Laringeal kanker (LK) is die 6de algemeenste kanker in die wêreld en die 2de algemeenste respiratoriese kanker, met "n benaderde 500 000 nuwe gevalle jaarliks wêreldwyd. Oor die afgelope paar jare het LK "n toenemende probleem geraak, veral in die Kleurling gemeenskap van die Wes Kaap. Die meganismes van die tumorvorming in LK is onbekend, alhoewel rook-en alkoholgebruik vername risiko faktore is. Die voorkoms van mutasies in TP53 is verskeie kere aangetoon in verskillende kanker tipes en daar word vermoed dat dit "n rol speel in tumorvorming. In hierdie studie is dus na mutasies in eksons 5 - 8 van TP53 gesoek in tumor biopsie weefsel (n=44) en bloed isolate (n=42) van Kleurling LK pasiënte d.m.v. polimerase ketting reaksie - enkelstring konformasie polimorfisme (PKR-ESKP) analisering en direkte volgorde bepaling. Bloed monsters van "n vergelykbare groep (n=40) is ook in die studie ingesluit as "n kontrole. Betekenisvolle positiewe korrelasies is gevind tussen die voorkoms van LK en ouderdom sowel as rook. Daarmee saam is daaglikse vleisinname as potensiële beskermende faktor gevind. In tumor biopsies is mutasies in 3 van die ondersoekte eksons gevind, wat 25% van die biopsie monsters verteenwoordig. Hierdie mutasies is uniek aan die tumor biopsie weefsels en dui op "n somatiese oorsprong van mutasies. Hierdie bevindinge bevestig dat die gedeelte tussen kodons 173 - 273 van TP53 "n hipermuteerbare gebied geassosieer met kankers is. Hierdie studie bevestig 6 nuwe mutasies. Daar is 'n hoë insidensie van slukderm kanker (SK) in Suid Afrika relatief tot die res van die wêreld. Hierdie soort kanker word veral gevind by die Swart populasie van die Transkei. Die doel van hierdie studie was om verskille tussen die TP53 mutasie patroon van die Kleurling gemeenskap van die Wes Kaap en die Swart gemeenskap van die Transkei te vergelyk. Hiervoor is die molekulêre struktuur van TP53, veral eksons 5 - 8, in 'n groep Kleurling SK pasiënte (n=42) wat behandel is by Tygerberg Hospitaal, Kaapstad, Suid Afrika, geanaliseer. Analisering is gedoen deur DNS van tumor, bloed en ook oënskynlike gesonde aangrensende weefsel van dieselfde pasiënte te onderwerp aan PKR-ESKP analise en direkte volgorde bepaling. Slegs 4 nukleotied veranderings is gevind in 124 volgorde bepalings, waarvan 2 nuwe veranderings is in SK. Hierdie 4 nukleotied veranderinge verteenwoordig 9% van al die tumors wat ondersoek is in die studie. Hierdie studie bewys dat die mutasiespektrum van TP53 in die Kleurling gemeenskap van die Wes Kaap grootliks verskil van die Swart gemeenskap van die Transkei. Dit impliseer dat verskillende etiologiese faktore moontlik 'n rol mag speel op die tumorvormingsproses in die 2 afsonderlike geografiese gemeenskappe. Hierdie is die onderwerp van 'n epidemiologiese studie wat deur die MNR onderneem word. Die laaste deel van hierdie tesis handel oor die kwantifisering en vergelyking van TP53 transkripsievlakke in SK tumor weefsel teenoor TP53 vlakke in gesonde slukderm weefsel van pasiënte in 'n unieke geografiese en etniese agtergrond. Die studie populasie in hierdie projek het bestaan uit Kleurling pasiënte (n=2) wat by Tygerberg hospitaal behandel is. Die "LightCycler" sisteem is gebruik vir die akkurate kwantifisering van TP53 boodskapper RNS vlakke. Ongelukkig is die verlangde resultate nie gekry nie as gevolg van onvoorsiene probleme wat ondervind is tydens die studie. Hierdie probleme sluit in die onvoldoende preserv RNS studies. Hierdie inleiers maak dit nou moontlik om die teenwoordigheid van TP53 RNS spesies sowel as die afwesigheid van DNS kontaminasie in een PKR amplifikasie stap te kan identifiseer. 'n Ander belangrike bydrae is die ontwikkeling van 'n goed geoptimaliseerde RNS ekstraksie metode vir moeilike starre weelfsel tipes (soos menslike slukderm weefsel in hierdie studie) en maak die ekstraksie van groot hoeveelhede RNS uit klein hoeveelhede van moeilik hanteerbare weefsel tipes moontlik. Om saam te vat, hierdie studie het betekenisvolle bydraes gemaak tot die veld van kankernavorsing deur die ontrafeling van die TP53 mutasiespektrum in beide laringeale sowel as slukderm kanker, in 'n populasie uniek aan die Wes Kaap. Die eerste deel van hierdie tesis is gepubliseer in Cancer Geneties and Cytogenetics (Barnard, D., K. Lehmann, E. G. Hoal, P. D. van Heiden, and T. C. Victor. 2003. The spectrum of mutations in TP53 in laryngeal cancer patients from a high-incidence population shows similarites to many of the known mutational hotspots. Cancer Genetics and Cytogenetics 145: 126-132) en 'n afskrif van die artikel is ingesluit in Appendix I. Hierdie werk is ook voorgedra (deur D. Barnard) by 'n internasionale kongres getiteld "Cancer of the Esophagus and Gastric Cardia: From Gene to Cure", wat in Amsterdam, Nederland gehou is gedurende 13 - 15 Desember 2002
513

Aspects of the preoperative pathway in pancreatic head malignancy

Amr, Bassem Ismail Metwaly Ismail January 2018 (has links)
Malignancy within the pancreatic head can arise from pancreatic duct, distal bile duct, ampulla or duodenum. Since September 2000, surgery for all pancreatic head malignancy (PHM) has been centralised into regional pancreatic centres where assessment of preoperative imaging and subsequent surgery is undertaken. As part of this guidance, surgery must be performed within 62-days of referral. This project will assess four aspects of the pre-operative pathway in PHM: 1) Potential variation in outcome of patients referred from different sites within a Cancer Network 2) Potential variation in outcome associated with different intervals to surgery within the 62 day guideline 3) The ability of interpretation of heterogeneous pre-operative CT scans from different hospitals to determine the resectability of PHM 4) The ability of CT scan to distinguish the different tumour types of PHM Images of a consecutive series of patients were re-reported and compared with final pathology reports. Good agreement was noted in determining the tumour origin of PHM (observed agreement = 0.758, Kappa= 0.6 (0.51-0.68)). In the assessment surgical outcomes, geographical isolation from the regional centre was not associated with delay to surgery. Variation in outcome between referral centres was however noted but this was not associated with travel distance. Although little association was noted between delay to surgery and outcome overall, a paradoxical improvement in survival was noted however for the small group of patients with ampullary tumours who waited longer than the median interval to surgery.
514

Association Between Altitude and Bronchopulmonary Cancer

Ching, Hung 01 January 2018 (has links)
As a validation study, this study addressed an under-researched area of bronchopulmonary cancer mortality and incidence. The association between altitude and bronchopulmonary cancer mortality and incidence was investigated using data from the Centers for Disease Control and Prevention Wide-ranging Online Data for Epidemiologic Research. The theoretical framework for my study was Bronfenbrenner's ecological model. This model emphasizes the relevance of social and physical environments that influence patterns of disease and injury and shape responses to these patterns of disease and injury. The age-adjusted bronchopulmonary cancer mortality and incidence rates per 100,000 people in the highest elevation and lowest elevation states were investigated. The data used in this study spans from 2006 to 2014. In this study, bivariate statistics were used to analyze the data. The relevant technique of performing an unpaired t-test was used. After performing age, gender, and race-stratified analysis, no significant difference in cancer mortality and incidence was found within the following three groups: Black or African American, Asian or Pacific Islander, and American Indian or Alaska Native. This was a new finding, as previous studies did not stratify for race. Cancer mortality and incidence were found to be lower in both the male and female groups for the highest elevation states. Cancer mortality and incidence were also found to be lower in all age categories for the highest elevation states. A positive social change impact of this study is that this research provides the groundwork for future studies to probe what in the environment is lowering the bronchopulmonary cancer mortality and incidence for the White population.
515

Cancer and the older person.

Cleary, Ann January 2007 (has links)
Older people represent an increasing proportion of new cancer diagnoses yet little is known about their experiences with cancer or their knowledge about risk factors, benefits of lifestyle modification to decrease risk or participation in early detection programs. Two studies were conducted, the first to document a lived experience with a new cancer diagnosis and the second to test for relationships between knowledge and attitude to cancer and self-reported participation in screening for breast, prostate and colorectal cancers. / http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1297244 / Thesis (D.Nurs.) -- School of Population Health and Clinical Practice, 2007
516

Family environment, time since diagnosis, and gender as predictors of psychosocial adaptation in oncology patients / Psychosocial adaptation of oncology patients

Barton, Marci A. January 2001 (has links)
The purpose of this study was to investigate the influence of gender, time since diagnosis, and the family environment on the psychosocial adaptation of cancer patients. This study was important because there is a deficit in the literature investigating the effects of the family environment on psychosocial adaptation in male and female cancer patients with diverse diagnoses. This study measured psychosocial adaptation by the patient's ability to adjust to cancer-related stressors in the areas of social relationships, involvement in health care, psychological well-being, household and work related duties, and family relationships. The family environment was measured by the patient's perceived level of cohesion, expressiveness, and conflict in the family.The study's sample consisted of 149 stage I or II cancer patients over the age of 50 with no prior cancer diagnosis, recurrence, or metastases. Participants completed a set of questionnaires, including the Psychosocial Adjustment to Illness Scale and the Family Relationship Index. The combination of gender, time since diagnosis, and the family environment, with demographic variables held constant, was significant and accounted for nearly one-third (27 %) of the variance in cancer patients' psychosocial adaptation. Results showed that the family environment is a significant predictor of psychosocial adaptation in cancer patients. Gender and time since diagnosis were not significantly related to psychosocial adaptation. Implications from this study are offered. / Department of Counseling Psychology and Guidance Services
517

Determining the anti-cancer properties of zinc and novel quinoxaline derivatives on lung cancer cells

Sibiya, Mixo Aunny January 2020 (has links)
Thesis (M.Sc. (Biochemistry)) -- University of Limpopo, 2020 / Despite major advancements in the development of various chemotherapuetic agents, treatment for lung cancer remains costly, ineffective, toxic to neighbouring normal noncancerous cells and still hampered by high level of remissions (Wistuba et al., 2018; Tana et al., 2016; Schiller et al., 2002). Synthesis of novel quinoxalines with a wide spectrum of biological activities has recently received considerable attention with promising anticancer drug activity since most of them do not affect non-cancerous cells and are derived from readily available less costly raw materials (Srivastava et al., 2014). Since combination treatment has been shown to augment and improve single drug treatment, trace elements were employed in this study in combination with quinoxalines derivatives (Gomez et al., 2016; Kocdor et al., 2015; Ku et al., 2012; John et al., 2010; Killile and Killilea, 2007). Zinc is an essential element that is integral to many proteins and transcription factors which regulate key cellular functions such as the response to oxidative stress, DNA replication, DNA damage repair, cell cycle progression, and apoptosis (Dhawan and Chadha, 2010). Owing to the importance of these two approaches, the aim of this study was to provide in vitro preliminary anticancer activity data on A549 lung cancer cells using combination of zinc and quinoxaline derivatives. An assessment of the quinoxaline derivatives ferric reducing power and DPPH free radical scavenging activity was performed. The cytotoxic and anti-proliferation activity of these derivatives and zinc on cancer cell lines was determined using the MTT assay. The ability of the quinoxaline derivatives and zinc to modulate oxidative stress was evaluated using the H2DCFDA fluorescence assay. Cell cycle arrest stages were analysed by flow cytometry through propidium iodide cell cycle analyses. The ability of the quinoxaline derivatives to induce apoptosis in cancer cells was assessed using DAPI/PI, Acridine Orange/Ethidium Bromide (AO/EB) and Annexin V-FITC/Dead Cell assays. Western blot was used to investigate the Bcl/Bax expression ratios in A549 lung cancer cells after treatment with quinoxaline derivatives, zinc and in combination. Of the four quinoxaline derivatives tested, 3-(quinoxaline-3-yl) prop-2-ynyl methanosulphate (LA-39B) and 3-(quinoxaline-3-yl) prop-2-yn-1-ol (LA-55) produced significant anticancer properties against A549 lung cancer cells at minimal concentrations of 25μM. Both quinoxaline derivatives displayed antioxidant properties and did not induce cell death in non-cancerous Raw 267.4 macrophage cells. Cytotoxicity was observed in A549 lung cancer, HeLa cervical cancer and MCF-7 breast cancer cells albeit inhibition was more pronounced in A549 lung cancer cells. Treatment of cancer cells with zinc also resulted in pronounced cytotoxicity at a minimal concentration of 25μM. Although reduced oxidative stress was observed in Raw 264.7 macrophages, in A549 lung cancer cells both compounds were able to increase ROS production which was accompanied by high levels of apoptosis when treated with derivatives and zinc alone but when in combination an improved higher level of apoptosis is observed. The improved anti-cancer activity of this drug combination treatment was further accompanied by lower Bcl/Bax expression ratios with upregulation of Bax in A549 lung cancer cells. The results of the study suggest that 3-(quinoxaline-3-yl) prop-2-ynyl methanosulphate and 3-(quinoxaline-3-yl) prop- 2-yn-1-ol are potential candidates drug for treatment of lung cancer. The use of these quinoxaline derivatives in combination with zinc can offer alternative treatment options for lung cancer. / National Research Foundation (NRF)
518

Systems-level characterization of ovarian cancer metabolism

Vermeersch, Kathleen A. 07 January 2016 (has links)
The purpose of this thesis was to characterize cancer metabolism in vitro using epithelial ovarian cancer as a model on an untargeted, systems-level, basis with particular attention paid to the difference between cancer stem cell metabolism and cancer cell metabolism. Two-dimensional gas chromatography coupled to mass spectrometry was used to measure the metabolite profiles of the ovarian cancer and cancer stem cell lines under normal baseline conditions and also under chemotherapeutic and environmental perturbations. These two cell lines exhibited significant metabolic differences under normal baseline conditions and results demonstrated that metabolism in the ovarian cancer stem cell line was distinct from that of more differentiated isogenic cancer cells, showing similarities to stem cell metabolism that suggest the potential importance of metabolism for the cancer stem cell phenotype. Glucose deprivation, hypoxia, and ischemia all perturbed ovarian cancer and cancer stem cell metabolism, but not in the same ways between the cell types. Chemotherapeutic treatment with docetaxel caused metabolic changes mostly in amino acid and carbohydrate metabolism in ovarian cancer cells, while ovarian cancer stem cell metabolism was not affected by docetaxel. Overall, these metabolic differences between the two cell types will deepen our understanding of the metabolic changes occurring within the in vivo tumor and will help drive development of cancer stem cell targeted therapeutics.
519

Identification and characterization of cancer-related genes in esophageal squamous cell carcinoma

Fu, Li, 付利 January 2007 (has links)
published_or_final_version / abstract / Clinical Oncology / Doctoral / Doctor of Philosophy
520

Therapeutic benefits of concurrent chemoradiotherapy for advanced nasopharyngeal carcinoma

Lee, W. M., Anne, 李詠梅 January 2008 (has links)
published_or_final_version / Medicine / Master / Doctor of Medicine

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