Central chondroid bone tumours are one of the most common primary bone tumours. Benign central chondroid tumours are termed enchondromas and its malignant counterpart are called chondrosarcomas. Enchondromas are frequently observed on routine imaging. Similarly, chondrosarcomas are the second most common primary bone tumour after osteosarcoma. Imaging is crucial in the diagnosis of central chondroid tumours and in the differentiation of enchondromas from chondrosarcomas. Furthermore, imaging plays a vital role in the staging of chondrosarcomas. In this thesis, the published scientific literature on the role of imaging in the diagnosis of benign chondroid tumours and chondrosarcomas and the role of imaging in the staging of chondrosarcomas is reviewed and summarised. Furthermore, the contribution of the authors’ published work is highlighted in the thesis. The first two articles are review articles which discuss the clinical and imaging features of benign and malignant chondrogenic tumours and the significance of imaging in the diagnosis of these tumours. The third article is an original article which investigates the theory of the pathogenesis of enchondromas. It is widely believed that enchondromas arise from cartilage islands which are displaced from the growth plate during the process of skeletal maturation. However, this theory is unproven, and the origin of this theory was forgotten prior to the authors’ study. Based on the incidental prevalence of enchondromas of the knee in the adult population of 2.9%, the study assesses the prevalence of cartilage islands/enchondromas in skeletally immature patients. In this study, no cartilage islands/enchondromas in skeletally immature patients were identified. The study therefore shows the rarity of enchondromas in skeletally immature individuals which is in contrast to the adult population. Furthermore, in view of the absence of cartilage islands in this study, the study raises doubts about the validity of the unproven theory. Lastly, the very origin of this theory is rediscovered in this thesis which has been forgotten in modern medicine. The fourth article is an original article which evaluates the role of diffusion-weighted MRI (DWI) in the diagnosis of central cartilage tumours. Prior to the authors’ study the role of DWI in the diagnosis of central cartilage tumours was uncertain. The authors’ study demonstrates that DWI cannot be used to differentiate between enchondromas and chondrosarcomas and that DWI does not aid in the distinction of low-grade chondroid tumours from high-grade chondrosarcomas. This is a finding which was not known prior to the study. The fifth article is an original article which assesses the utility of conventional MRI in the differentiation of low-grade from high-grade chondrosarcomas of long bone. Prior to the authors’ study the role of conventional MRI in the differentiation of low- grade from high-grade chondrosarcomas of long bone was unknown. The authors’ study shows that bone expansion, active periostitis, soft tissue mass and tumour length can be used to differentiate high-grade from low-grade chondral lesions of long bone on conventional MRI. Furthermore, the presence of these four MRI features shows a diagnostic accuracy of 95.6%. These findings were not known prior to the study and have significantly furthered the knowledge about the role of conventional MRI in the grading of chondrosarcoma of long bone. The sixth article is an original article which evaluates the role of bone scintigraphy and Computed Tomography of the chest in the staging of chondrosarcoma of bone. Whilst guidelines regarding the staging of bone sarcomas state that bone scintigraphy should be performed to assess for the presence of skeletal metastases and that Computed Tomography (CT) of the chest should be performed to evaluate for possible pulmonary metastases, there has been no research on the utility of bone scintigraphy in chondrosarcoma of bone and on the role of CT-chest in the staging of chondrosarcomas. Furthermore, the prevalence of skeletal and pulmonary metastases of chondrosarcoma at presentation was unknown prior to this study. The authors’ study demonstrated no skeletal metastases on bone scintigraphy in chondrosarcoma of bone at presentation. In contrast, pulmonary metastases were observed in approximately 5% of all patients with chondrosarcoma at presentation on CT-chest. The finding therefore demonstrates the rarity of skeletal metastases in chondrosarcoma of bone at presentation which is in contrast to osteosarcoma and Ewing sarcoma. The study therefore concludes that there is little role for skeletal scintigraphy in the surgical staging of chondrosarcoma. In contrast, the study shows that there is a role for CT-chest in the staging of chondrosarcoma. These above described findings are important new findings and represent a significant contribution to the knowledge base regarding metastatic behaviour of chondrosarcomas at presentation and regarding the staging of chondrosarcoma of bone. In summary, the authors’ publications have significantly enhanced and furthered the understanding of the pathogenesis of enchondromas, the role of functional MRI in the differentiation of enchondromas from chondrosarcomas, the utility of MRI in the grading of chondrosarcomas and the role of skeletal scintigraphy in the staging of chondrosarcomas.

Phosphatase and tensin homologue deleted on chromosome ten (PTEN) is one of the most commonly altered tumor suppressors in human cancer. It is a dual-specificity phosphatase that by converting the lipid second messenger PIP3 to PIP2 antagonizes the PI3K/AKT signaling pathway. PTEN also has numerous, albeit controversial nuclear functions, which thus far have been shown to be independent of its phosphatase activity. Although a number of studies have described that loss or gain of PTEN protein expression alters gene expression patterns, relatively little is known about the exact mechanism. In this research study, we investigated PTEN’s influence on gene expression and its role in transcription regulation. First, we established mouse embryonic fibroblasts (MEFs) as a suitable model system to study the effects of PTEN loss on gene expression. Using an Adeno-virus containing Cre-recombinase, Pten expression could be ablated efficiently in MEFs carrying loxP sites flanking exon 5 of the endogenous Pten locus. Genome-wide mRNA microarray analysis revealed that Pten deletion decreased the transcript levels of a subset of genes and increased the transcript levels of a different subset of genes. Moreover, by uncoupling these effects from PTEN’s role in the PI3K/AKT pathway we discovered that Pten loss can alter gene expression in a PI3K/AKT-dependent as well as a PI3K/AKT-independent manner. The upregulated genes were enriched for genes involved in DNA binding, replication, and repair, but also for regulation of gene expression. Gene expression can be influenced by histone modifications. However, loss of PTEN did not affect histone modifications globally as evidenced by western blotting. Using native ChIP-Seq experiments we showed that loss of PTEN altered the levels of H3K36me3 and H3K27me3 on a subset of genes and markedly decreased levels of H3K27ac at most enhancers as well as super-enhancers. However, RNAPII occupancy on enhancer-associated genes did not decrease, suggesting that the modulation of enhancer strength did not affect RNAPII recruitment to TSS. In Chapter 3 we identify a nuclear pool of Pten that could associate with chromatin. Furthermore, we are the first to report that nuclear PTEN can directly interact with components of the transcription machinery including CDK7, CDK9, Cyclin T1, AFF4, and RNAPII. Loss of PTEN increased phosphorylation of Ser2 and Ser5 of the RNAPII CTD as well as RNAPII occupancy on promoters of expressed genes indicating an increase in transcriptional activity in PTEN-/- cells. Furthermore, PTEN deletion resulted in the upregulation of genes which are part of the important “Achilles cluster”, previously shown to confer sensitivity to transcription inhibition. We believe that it is over-expression of those genes that render PTEN deficient cells especially sensitive to transcription inhibitors such as THZ1, Triptolide, Flavopiridol and LDC000067. Over-expression of wild type PTEN but not a phosphatase-dead mutant of PTEN could decrease cells’ sensitivity to treatment with THZ1 or Flavopiridol. It also decreased protein levels of p-AKT Ser473 as well as RNAPII Ser2P and Ser5P suggesting that the phosphatase activity of PTEN is important for its role in transcription regulation. In sum, we propose a model in which PTEN binds to CDK7, CDK9, Cyclin T1, RNAPPII and/or AFF4 thereby exerting a negative regulatory effect on the activity of transcription complexes. Upon loss of PTEN the negative regulatory effect is eliminated and transcription of a subset of genes increases. It is most likely these genes that confer sensitivity to transcription inhibition on PTEN-/- cells. The better understanding of this oncogenic mechanism may reveal novel therapeutic opportunities, and ultimately we propose that the sensitivity of PTEN deficient cells to inhibitors of transcription could provide an effective clinical strategy to target PTEN deficient cancers.

Class of 2007 Abstract / Objectives: In this paper we analyzed the time frame for oncology drugs that were designated as a fast track drug and the time transition from a phase II to phase III clinical trial completion. Methods In our study we utilized oncology drugs that were approved between the years of 2000-2006 (FDA.gov). We then analyzed the CDER data base that provided information to Fast Track drugs that have been approved within the time period as determined by the FDA selection criteria (21 CFR 312.81(a)). Under certain circumstances, the FCA may consider reviewing portions of a marketing application in advance of the complete New Drug Application (NDA) or Biologic License Application (BLA). We will evaluate fast track designated products which may also be eligible to participate in FDA’s Continuous Marketing Applications Pilot 1 or Pilot 2 programs. For our analysis, we specifically selected oncology drugs. In particular, we analyzed 32 drugs from the stated time period. Each fast track drug was then selected and analyzed for its clinical phase development time period based on news announcements during clinical trails. For each announcement we conducted an event study analysis through lexis Nexus with respect to the announcement of a clinical trial enrollment, clinical trials news (Phase I, II, III). Results: The results of our preliminary study show that there was a shorter time to development transition for the fast track oncology drugs. The oncology clinical phase transition from II to three on average lasted 12 months with a range of 2 - 29 months The average length of the phase development had to excludes 4 drugs due to the lack of information provided from the LexisNexis database. The current timeline for fats track drugs has shown a decrease in transition from clinical trials to the market. In the example of Spyrcel, the data from our study had to be excluded, there was a definitive difference in the time to approval process for the drug as compared to other standard review entities. The approvals for dasatinib, or Sprycel, for refractory CML was shown to move through the development to approval in one of the fastest timeframes in modern development. Since its first clinical study on in Gleevec-resistant patients, the medication was decided on entering an accelerated timeline. It took us just 25 months to bring Sprycel from first-in-human dosing to a regulatory submission. In contrast, the industry average for this cycle time is 6.4 years which is three times greater than the cycle time for Sprycel. Conclusions: The new Subpart H regulations state that post-marketing studies to confirm clinical benefit that would consist usually by "studies underway” at the time of accelerated approval, this has not always been the case and is not a requirement (Dagher R, Johnson J, Williams G et al). In conclusion, the accelerated approval program in oncology has been successful in making 18 different products available to patients for 22 different cancer treatment indications since the inception of the fast track program. From the current data and transition information, there is a comparative difference between the clinical phase transitions from phase II to Phase III clinical trials. However, this preliminary data needs to be further evaluated against the standard FDA review process from oncology drugs. Moreover, further studies will be needed to interpret whether the average length of oncology studies biases the value of our study.

During apoptosis, caspase cleavage of ROCK1 removes an auto-inhibitory region yielding a constitutively active kinase fragment. This results in phosphorylation of downstream targets that promote contractile force generation leading to cell shrinkage, membrane blebbing and nuclear disintegration. To address fundamental questions regarding the purpose of ROCK1 cleavage and consequent apoptotic morphological features, a novel mouse model was generated that carries a single amino acid substitution in the caspase cleavage site (D1113A) that converts ROCK1 to a caspase-resistant non-cleavable (ROCK1nc) form. When apoptosis was induced in ROCK1nc cells, morphological features were significantly impaired, although the biochemical apoptotic program itself was unaffected. To understand the biological role of apoptotic morphological features in the maintenance of tissue homeostasis, acute liver damage was induced in mice with the liver-selective genotoxic compound diethylnitrosamine (DEN). Following DEN treatment, there were increased TUNEL-positive apoptotic cells and increased neutrophil infiltration in ROCK1nc mice. Histologically, ROCK1nc livers were more damaged, paralleled by higher serum alanine transaminase levels. We hypothesized that uncleared apoptotic debris undergoing secondary necrosis may release damage associated molecular patterns (DAMPs) that may aggravate liver damage by recruiting neutrophils to the liver. Indeed, inhibiting the cytokine activities of HMGB1 reduced neutrophil infiltration as well as liver damage in ROCK1nc mice. Furthermore, to determine whether defects in tissue damage responses in ROCK1nc mice would affect tumour development, the ROCK1nc mutation was introduced into two different cancer models, specifically the DEN-induced hepatocellular carcinoma and Eµ-myc lymphoma mouse models. Defective caspase cleavage of ROCK1 promoted increased infiltration of CD8+ T-cells in ROCK1nc liver tumours and had a protective effect against tumour development in both tumour models. Taken together, our results indicate that apoptotic morphological features suppress inflammation which helps to maintain tissue homeostasis but enables tumourigenesis.

Prostate cancer is a significant health problem for men in the western world. Of particular concern are patients who present with aggressive, invasive and metastatic disease, and develop lethal castration-resistant prostate cancer (CRPC) following androgen deprivation therapy. The activation of Wnt/β-catenin signalling is a common event in patients with the poorest prognosis, and frequently associated with the loss of PTEN and activation of the PI3K/Akt signalling pathway. However, the molecular basis for the significant impact of these aberrations in prostate cancer remains unclear. By using pre-clinical transgenic in vivo models, we have demonstrated that β-catenin is a potent proto-oncogene that drives prostate cancer tumourigenesis. Concurrent heterozygous loss of Pten exacerbates β-catenin-driven tumour progression and decreases host survival, while tumours are most aggressive when Pten is deleted. By investigating differential gene and protein expression, we have characterised co-operation between β-catenin activation and Pten loss through a complex network of intrinsic and extrinsic molecular events. These drive survival, growth and proliferation signals, and modulate tumour-immune response interactions to evade anti-tumourigenic processes, resulting in aggressive prostate cancer. Furthermore, by examining novel in vivo models of β-catenin-driven CRPC, we have indicated that β-catenin may promote treatment-resistance through androgen receptor (AR) reprogramming. We propose a mechanism for β-catenin-driven CRPC that is independent of classical AR signalling, and mediated through significant upregulation of canonical and non-canonical Wnt pathway components, which may be effectively targeted by Wnt inhibition. In summary, this thesis highlights a number of potential biomarkers and molecular targets that may be exploited to develop new strategies to manage patients with aggressive prostate cancer, to improve prognosis and avoid progression to lethal castration-resistant disease.

This research work aimed to assess the Health-Related Quality of Life of women with breast and gynecological cancer undergoing adjuvant antineoplastic chemotherapy. A descriptive study with cross-sectional design and quantitative approach. The research took place at the chemotherapy ward of a nonprofit tertiary referral hospital for cancer surgery in Fortaleza-CE, Brazil. The study sample consisted of 72 women. Data collection happened from April to May 2012. After given informed consent, all women participated in individual interviews and completed the research protocol consisting of a questionnaire of socio-demographic data and the scale of the European Organization for Research and Treatment of Cancer: Quality of Life Evaluation in cancer patients (QLQ-C30 version 3.0). From the analytical study, we highlight the following results: most patients considered the overall QOL measure as âgreatâ with predominant scores 06 and 07. The sub-scale of the item for Social Functioning had the best score with 54.2. On the other hand, we observed the worst performances of women in the Role Performance, Emotional, Physical, and Cognitive Functioning. Regarding the most frequent or intense symptoms, the most reported were pain, fatigue, insomnia, and loss of appetite. At the opposite extreme were dyspnea, nausea and vomiting, with a mean score of 81.9 and 86.1, respectively. The item relating to Financial Difficulty represented a factor that negatively influences the Quality of Life with representation of 44.4 on the average score. Thus, we conclude that the interaction between clinical situation and treatments for the coexisting disease have cumulative and deleterious effects on Quality of Life, emphasizing the specific concerns related to cancer. It is worth mentioning that the predictive factors for Health-Related Quality of Life identified in this study should receive more attention in the health care practice, they may represent also starting points for future studies that address in depth the different aspects involving the QOL of cancer patients. / Este trabalho de investigaÃÃo teve como objetivo avaliar a Qualidade de Vida Relacionada à SaÃde de mulheres com cÃnceres de mama e ginecolÃgico submetidas à quimioterapia antineoplÃsica adjuvante. Estudo de natureza descritiva com delineamento transversal e abordagem quantitativa. O local da pesquisa foi o setor de quimioterapia de uma instituiÃÃo hospitalar filantrÃpica de nÃvel terciÃrio e referÃncia em cirurgia oncolÃgica na cidade de Fortaleza-Ce. A amostra do estudo foi composta por 72 mulheres. A coleta de dados foi realizada no perÃodo de abril a maio de 2012. ApÃs dado o consentimento informado, todas as mulheres participaram de uma entrevista individual e preencheram o protocolo de investigaÃÃo constituÃdo por um questionÃrio de dados sÃcio demogrÃficos e pela escala da European Organization for Research and Treatment of Cancer: AvaliaÃÃo da Qualidade de Vida do doente oncolÃgico (QLQ-C30 versÃo 3.0). Do estudo analÃtico realizado, destacam-se os seguintes resultados: A medida global de QV foi considerado pela maioria como âÃtimaâ com predomÃnio das notas 6 e 7. A sub-escala no item Funcionamento social obteve melhor escore com 54,2. Em contrapartida, os piores desempenhos das mulheres foram observados no nÃvel do Desempenho de PapÃis, Funcionamento Emocional, FÃsico e Cognitivo. Quanto aos sintomas mais frequentes ou intensos foram relatados a dor, fadiga, insÃnia e perda de apetite. No extremo oposto, estavam a dispnÃia, nÃuseas e vÃmitos, com um escore mÃdio de 81,9 e 86,1, respectivamente. O item referente à Dificuldade Financeira mostrou-se como fator que influencia negativamente na Qualidade de Vida com representaÃÃo de 44,4 na mÃdia de escore. Conclui-se que a interaÃÃo entre os quadros clÃnicos e os tratamentos da doenÃa coexistente tem efeitos cumulativos e deletÃrios sobre a Qualidade de Vida, acentuando as preocupaÃÃes especÃficas relacionadas ao cÃncer. Ressalta-se que os fatores preditivos de Qualidade de Vida Relacionada à SaÃde identificados neste estudo devem ser foco de maior atenÃÃo na prÃtica assistencial e podem representar pontos de partida para estudos futuros que abordem, em profundidade, os diferentes aspectos que envolvem a QV de pacientes com cÃncer.

nÃo hà / O cÃncer afeta o paciente de forma abrangente, repercutindo na sua qualidade de vida. As tecnologias em saÃde, como a utilizaÃÃo de dispositivos de infusÃo contÃnua na administraÃÃo de antineoplÃsicos, visam favorecer o tratamento, repercutindo positivamente no bem estar dos pacientes. A pesquisa objetivou avaliar a qualidade de vida de pacientes oncolÃgicos que utilizam dispositivo para infusÃo contÃnua de antineoplÃsicos a partir da escala WHOQOL-bref; e os objetivos especÃficos foram: Caracterizar os pacientes oncolÃgicos que utilizam dispositivo para infusÃo contÃnua de antineoplÃsicos, quanto aos aspectos sociodemogrÃficos e clÃnicos; identificar os domÃnios de qualidade de vida afetados nos pacientes que utilizam dispositivo para infusÃo contÃnua antineoplÃsicos; comparar os domÃnios de qualidade de vida dos pacientes no primeiro e terceiro ciclo de aplicaÃÃo dos antineoplÃsicos. Estudo descritivo, exploratÃrio, quantitativo, longitudinal do tipo painel, realizado no perÃodo de abril a julho de 2013, com 28 pacientes em tratamento antineoplÃsico com a utilizaÃÃo de dispositivo de infusÃo contÃnua, de uma operadora de plano de saÃde, em Fortaleza, CearÃ. A coleta de dados ocorreu atravÃs de visita domiciliar, durante o primeiro e terceiro ciclos de administraÃÃo do antineoplÃsico, com aplicaÃÃo de dois questionÃrios: sociodemogrÃficos e clÃnicos; e avaliaÃÃo de qualidade de vida WHOQOL-bref. O tratamento dos dados foi realizado com auxÃlio de um software estatÃstico STATA. Aplicou-se o coeficiente Alfa de Cronbach, para avaliaÃÃo da consistÃncia interna das respostas, o teste de igualdade de mÃdias Wilcoxon para dados pareados e o teste de Qui-quadrado de TendÃncia linear. A correlaÃÃo dos domÃnios foi feita atravÃs do coeficiente de CorrelaÃÃo Linear de Spearman. Predominaram na amostra (n=28), mulheres (53,6%), faixa etÃria 51 a 60 anos (32,1%), casadas (60,7%), catÃlicas (67,9%), exercendo atividade laboral (71,5%). A neoplasia maligna predominante foi a de cÃlon e reto (57,2%), com metÃstase (53,6%) hepÃtica. O tratamento cirÃrgico mais empregado foi a colectomia (39,3%). O protocolo mais utilizado foi o FOLFOX (67,9%), com intenÃÃo paliativa (57,1%). Os efeitos indesejados mais evidenciados foram os gastrointestinais em associaÃÃo com fadiga (39,3%). O Ãndice de alfa de Cronbach atestou a confiabilidade do estudo. Avaliando a qualidade de vida quanto Ãs mÃdias dos itens globais e domÃnios da escala, a percepÃÃo quanto a qualidade de vida foi considerada regular; e a satisfaÃÃo com a saÃde ruim, em ambos os ciclos do tratamento. Quanto a avaliaÃÃo dos domÃnios, o de maior mÃdia foi o das relaÃÃes sociais, e o de menor, o psicolÃgico. A avaliaÃÃo da qualidade de vida foi vista como regular, em ambos os ciclos. O dispositivo favorece aspectos relacionados à independÃncia, desempenho de atividades diÃrias e laborais, porÃm nÃo à isento de aspectos negativos, influenciando a percepÃÃo dos pacientes, pelo medo do desconhecido, presenÃa de um aparato no cotidiano, desconforto quanto à movimentaÃÃo. Foi possÃvel concluir que nenhum fator isoladamente vai influenciar positiva ou negativamente a qualidade de vida de pacientes oncolÃgicos, independente do momento vivido. à importante saber os determinantes neste sentido, permitindo a implementaÃÃo de estratÃgias para preservar a qualidade de vida desta clientela. / Cancer affects the patient in an extensive way, reverberating in his quality of life. The technology in health, such as the use of continuous infusion device in the administration of antineoplastic aimed at favoring the treatment, positively reverberating in the welfare of the patient. The research aimed at evaluating the quality of life of the patient who use an antineoplastic continuous infusion device from the WHOQOL-bref scale; and the specific objectives were: to identify the domains of quality of life affected in the patients who use the antineoplastic continuous infusion device, as to the socio-demographic and clinical aspect; to compare the domains of quality of life of the patients in the first and in the third cycle of application of antineoplastics. It is a descriptive, exploratory, quantitative, longitudinal study of panel type, made from April to July 2013, with 28 patients under antineoplastic treatment with the use of continuous infusion device, of a health plan operator, in Fortaleza, CearÃ, Brazil. The data collection was made through home visits during the first and the third cycle of administration of antineoplastics, with the application of two questionnaires: socio-demographic and clinical; and the WHOQOL-bref evaluation of quality of life. The treatment of the data was made with the help of STATA statistics software. The CronbachÂs alfa coefficient was applied, for the evaluation of the internal consistence of the answers, the Wilcoxon test of average equality for paired data and the Chi-Squared test of linear tendency. The correlation of the domains was made through the coefficient of SpearmanÂs linear correlation. The following items predominated in the sample (n=28) were: women (53.6%), age range from 51 to 60 years (32.1%), married (60.7%), catholic (67.9%), working (71.5%). The predominant malign neoplasia was of colon and rectum (57.2%), with hepatic metastasis (53.6%). The most employed surgical treatment was colectomy (39.3%). The most used protocol was FOLFOX (67.9%), with palliative intention (57.1%). The most evident unwelcome effects were the gastrointestinal ones associated with fatigue (39.3%). The CronbachÂs alfa coefficient attested the reliability of the study. Evaluating the quality of life concerning the average of the global items and domains of the scale, the perception as to the quality of life was considered regular; and the satisfaction with the bad health, in both cycles of the treatment. As to the evaluation of the domains, the highest average was the one concerning the social relations and the lowest average was the psychological domain. The evaluation of the quality of life was seen as regular, in both cycles. The tool favors aspects related to independence, performance of daily and labor activities, but it is not exempt of a negative aspect, influencing the perception of the patients, by the fear of the unknown, the presence of a device in the daily life, discomfort related to moving. It was possible to conclude that no isolated factor will positively or negatively influence in the quality of life of oncological patients, independently of the moment lived. It is important to know the determinants in this sense, allowing the implementation of strategies to preserve the quality of life of this clientele.

Systemic lupus erythematosus (SLE) is an autoimmune disease of unknown aetiology. Both genetic and environmental factors are known to contribute to disease development. Pathogenesis involves the production of autoantibodies, and the formation of immune complexes, leading to inflammation and destruction of autologous tissue. SLE is a heterogeneous disease both longitudinally and between affected individuals, and is characterised by periods of exacerbation, known as flares, and periods of remission. The ubiquitous human herpes viruses, cytomegalovirus (HCMV), and Epstein-Barr virus (EBV) have been associated with disease by a variety of mechanisms. Data compiled here suggests SLE patients have elevated IgG responses to HCMV and EBV, but unlike healthy controls these responses do not accumulate with age. No association has been found between the carriage of these viruses, or the magnitude of response against these viruses, and any clinical measurements of disease activity. EBV load is 5.4 times higher in SLE patients than controls. Azathioprine treatment is associated with a 4.4 fold rise in EBV load, no other drugs show associations with EBV load. Among SLE patients EBV load is inversely correlated with CD8+ T-cell IFN\(\gamma\) responses, suggesting impaired T-cell responses are the cause of elevated load. HCMV seropositivity is associated with a 7-year delay in development of disease among SLE patients, and a reduction in plasma IFN\(\alpha\) concentration.

γδ T cells play a central role in the detection of epithelial stress as a component of the lymphoid stress surveillance response. Despite their implication in a range of conditions, including several cancers, little is known about how they interact with their antigenic targets, particularly the interaction of γδ TCRs with their ligands. In this thesis I used molecular and structural modelling techniques to characterise recognition of an epithelial stress ligand, EphA2, by a Vδ1+ γδ T cell, MAU. This resulted in a tripartite model of recognition, involving coordinated interaction of EphA2 with both the TCR and its cognate A-ephrin ligands on the T cell, and the identification of a surface patch on the ligand binding domain of EphA2 that potentially represents a TCR binding site. I also performed sequence-level TCR repertoire analysis to assess γδ T cell populations in human colon and liver, and explored, the effect of chronic cytomegalovirus infection on the Vδ1+ γδ T cell repertoire, the first such analysis of its kind. These studies suggested the Vδ2negative repertoire in humans is diverse and largely private, but also highlighted a Vγ5Vδ1 population that was selectively detected in cytomegalovirus-seropositive individuals, and may be involved in cytomegalovirus immunity.

Glioblastoma is a highly malignant and aggressive high grade glioma with a poor prognosis. The low survival rates stem from tumour progression, late intervention, ineffective therapies and drug resistance, requiring new therapeutic and diagnostic approaches. Lipid droplets are dynamic organelles suggested to be influential facets of cancer metabolism and biology in many tumours. In glioblastoma lipid droplets have been associated with hypoxia higher clinical grades and poor survival however the cellular pathways underlying lipid droplet metabolism remain unclear. Using a publically available database of grade 2 ta 4 glioma gene expression, we observed that genes associated with lipid droplet metabolism were important prognostic survival and tumour progression indicators. Moreover, through confocal microscopy, flow cytometry and NMR-based methods, we observed that uptake of exogenous lipids and adipose triglyceride lipase-mediated lipid shuttling produced lipid droplets whilst autophagy was vital to lipid droplet breakdown. ATGL-mediated lipid shuttling was further observed to prevent unsaturated fatty acid oxidative damage. Finally, we investigated the effect of pharmacological lipid droplet manipulation and observed that autophagy inhibition can improve temozolomide and irradiation cytotoxicity. Taken together our data suggests that understanding lipid droplet metabolic pathways may generate prognostic bio-markers of survival and progression and improve current therapies.