Oesophageal adenocarcinoma (OAC), a cancer with dismal prognosis, has been increasing rapidly in incidence over the last 30 years, nowhere more so than in the UK. Intriguingly, it is a disease predominantly among white males, but there is a paucity of data from England. In performing a range of epidemiological studies, it has been confirmed that OAC has risen five-fold in the West Midlands, UK, five times more common among men, and predominantly a disease among Caucasians. A reduced incidence of OAC was identified among subjects with prostate cancer, suggesting a protective effect of anti-androgen therapy. Examination of a general practice database revealed a negative association with aspirin, non-steroidal anti-inflammatories and statins with OAC, and a positive association with inhaled steroids, increasing number of drugs with a side effect of reducing the lower oesophageal sphincter, and drugs used for asthma/COPD. Finally, a region wide case-control study, confirmed the positive association seen with increasing body mass index, waist circumference, smoking and reflux symptoms, with negative associations seen with a diet high in fruit and vegetables. This work has identified potentially modifiable risk factors that may be employed to reduce the incidence of oesophageal adenocarcinoma, and better help stratify those most likely to benefit from endoscopic surveillance.

Human papillomavirus (HPV) E2 is essential for transcriptional regulation of viral oncoprotein expression and the replication and persistence of episomal HPV genomes. Episomal persistence is mediated by tethering of viral genomes to host cell chromosomes during mitosis. Previous work demonstrated that interaction of E2 with the cellular DNA helicase ChlR1 is necessary for viral genome tethering. Therefore, disruption of this interaction is a potential therapeutic target for persistent HPV infections. To investigate the use of fragment-based drug discovery in the development of novel inhibitors of the E2-ChlR1 interaction, a fragment library was screened to identify those that bind E2 and several hits were identified. Concurrently, the interaction between HPV16 E2 and ChlR1 was characterised and shown to be a direct protein-protein interaction. The binding sites within E2 and ChlR1 were mapped and this information was used to identify a mutant E2 protein unable to bind ChlR1 (E2-Y131A). E2-Y131A was functionally characterised. HPV16 genomes encoding E2 wild type and Y131A were transfected into primary human keratinocytes to study the differentiation-dependent virus life cycle. Mutant genomes failed to establish genome maintenance, providing strong evidence that the interaction between HPV16 E2 and ChlR1 is necessary for the persistence of HPV infection.

Introduction: Paediatric low grade brain tumours present diagnostic and prognostic challenges, providing a need for better non-invasive imaging characterization. The value of \(^1\)H Magnetic Resonance Spectroscopy (MRS) performed on 5 scanners in the diagnosis and prognostication of an extensive bi-centre cohort of low-grade gliomas is investigated. Methods: Single voxel MRS was performed routinely in children with brain tumours at the Birmingham Children’s Hospital and Queen’s Medical Centre. Histopathological features were semi-quantified and in vitro \(^1\)H NMR used to study pilocytic astrocytoma cell lines. Magnetic Resonance Spectroscopic Imaging (MRSI) and texture analysis of MR images were performed. Results: MRS detects differences between subgroups of low grade brain tumours in children and between tumours of the same histology. High myo-inositol and glycerophosphocholine and low phosphocholine are markers of good prognosis. Histological correlates for MRS metabolites have been identified and paediatric pilocytic astrocytoma cell lines (‘typical’, metastatic and recurrence) have been discriminated. The value of MRSI in answering clinical questions has been demonstrated. Texture analysis achieved high accuracy in the diagnosis of paediatric posterior fossa tumours. Conclusion: Advanced MR techniques have a significant role in the study of paediatric brain tumours, and promising results from MRS, MRSI and texture analysis are reported here.

Heterogeneous blood vessels are created by angiogenesis and vasculogenesis in colorectal cancer (CRC). Assessing endothelial activities had promising applications. However no marker has translated to clinical care. Hence a multifactorial assessment or ‘endotheliome’, including angiogenic activity, the ‘angiome’, was proposed. I tested that circulating cellular and plasma biomarkers determined outcome(s). Flow cytometry quantified circulating endothelial cells (CECs, displaced from blood vessels) and endothelial progenitor cells (EPCs, for vasculogenesis). Plasma markers measured by ELISA were: von Willebrand factor (vWf, for endothelial damage/turnover), soluble E-selectin (adhesion in tumour migration), vascular endothelial growth factor (VEGF) and angiogenin (for the ‘angiogenic switch’). All markers were prospectively quantified in 154 CRC participants before treatment and compared to non-cancer controls. They were tested against the tumour’s histopathology and repeated after surgery +/- adjuvant therapy. CECs and EPCs were highest in CRC and correlated to VEGF only. Angiogenin was diagnostic of CRC and vWf predicted metastasis. All markers fell after surgery but inconsistently after adjuvant treatment. Lower CD34+CD45- cells identified responders to anti-angiogenic therapy. Models incorporating CEC, EPC, angiogenin and CRC stage predicted progression within 2 years better than CRC stage alone. In summary, the endotheliome and angiome are determinants of outcomes and may aid decisions on therapeutic strategies.

Nasopharyngeal carcinoma (NPC) is endemic in Southern China and South East Asia, causally linked to Epstein-Barr virus (EBV) infection, and frequently shows dysregulation in a number of stem cell maintenance signalling pathways. This thesis has endeavoured to investigate the status of one of these pathways; the Hedgehog (HH) signalling pathway, in NPC tumours, and reveals the novel finding that EBV is able to active the HH signalling pathway through autocrine induction of the SHH ligand in the C666.1 authentic EBV-positive NPC-derived cell line and latently infected epithelial carcinoma cell lines. This study demonstrates that constitutive engagement of the HH pathway in EBV-infected epithelial cells in vitro induces the expression of a number of stemness-associated genes and imposes stem-like characteristics. Using epithelial cells expressing individual EBV latent genes, this study also investigates the viral protein responsible for HH dysregulation demonstrating that EBNA1, LMP1 and LMP2A are all capable of inducing SHH ligand and activating the HH pathway, but only LMP1 and LMP2A are able to induce expression of stemness-associated marker genes. These findings not only identify a role for dysregulated HH signalling in NPC oncogenesis but also provide a novel rationale for therapeutic intervention.

The Anaphase Promoting Complex/Cyclosome (APC/C) is a multi-subunit E3 ubiquitin ligase that regulates mitotic progression through targeting substrates for degradation by the 26S proteasome. In order to assess APC/C post-translational modification status, and identify novel APC/C substrates and regulators, a comprehensive analysis of the APC/C and APC/C-interacting proteins by mass spectrometry was undertaken. RNA polymerase I was identified as an APC/C-interacting complex, and the interaction was validated by reciprocal co-immunoprecipitation, GST pull-down and immunofluorescent confocal microscopy. Both RPA194 protein levels and RNA Polymerase I transcription were shown to be dependent upon APC/C activity. Ablation of APC/C function by RNAi interference increased RPA194 protein levels, and elevated RNA polymerase I activity significantly, as quantified by 5’-Fluorouridine incorporation into nascent pre-rRNA, and the increase in absolute levels of 45S, 28S and 18S rRNA transcripts, relative to non-silencing controls. A number of other potential APC/C substrates and regulators were identified by mass spectrometry. Many of these interacting proteins contained APC/C consensus degron motifs. The APC/C was also shown to be a major substrate for acetylation; a number of APC/C subunits were identified as being acetylated in vivo. In this regard, APC3 was shown to be a substrate for both CBP and p300 acetyltransferases.

The research question in this project explores self-care practices that oncology providers utilize to manage stress, burnout, and compassion fatigue in their work environment. As an exploratory study, this research project examines self-care practices among the oncology providers and how self-care relates to the quality of patient care. The survey provided to the participants focused on the individual well-being such as spiritual, social support, physical, and emotional support. Findings from this study indicated that oncologist utilize spiritual self-care more than any other medical professional. The older adults utilize their social support systems more than the younger adults. Individuals with three or more children are better at utilizing their social support, physical self-care, and emotional support systems than individuals with two or less children.

Chromosomal translocations involving the mixed-lineage leukemia (MLL) gene lead to acute myeloid or lymphoid leukemias that are often associated with poor prognosis, particularly in infants. The translocations result in in-frame fusion between MLL and one of the over sixty known partner genes that are heterogeneous in nature. AF4 and AF9 are two of the most common MLL fusion partners. Importantly, they also interact specifically with each other in subnuclear foci. An AF4-mimetic peptide which disrupts the AF4-AF9 interaction is able to cause necrotic cell death in leukemic cell lines harboring MLL-AF4 or MLL-AF9 fusion oncogenes, emphasizing the importance of the AF4-AF9 interaction in leukemias caused by these fusions. AF4 and AF9 have been isolated as components of multiple transcription elongation complexes whose other members include the RA polymerase II regulator pTEFb and the chromatin modifying enzyme Dot1. Dot1 and its unique histone H3 lysine 79 methyltransferase activity are implicated in leukemias associated with MLL chimeric ncogenes. Data presented in this dissertation indicate that both AF4 and Dot1 are critical co-factors for MLL-AF9 associated leukemias. Interruption of the AF4---MLL-AF9 interaction, either by mutations or by overexpression of a dominant negative AF4 fragment, abolishes MLL-AF9---mediated hematopoietic cell immortalization as well as MLL target gene activation. In addition, loss of Dot1 function compromises cell viability by triggering apoptosis in hematopoietic cells immortalized by MLL-fusion oncoproteins. These findings poses AF4 and Dot1 as potential therapeutic targets for treatment of acute leukemias associated with MLL fusio oncogenes / acase@tulane.edu

Cancer is an illness that knows no international boundaries. There are more than eight million global cancer deaths each year. A life-threatening diagnosis generates significant emotional problems for many patients across cultures. Death distress—consisting of death depression, death anxiety and death obsession—often results in poorer treatment adherence and lower overall health and quality of life. The purpose of this study was to determine whether religiosity has a moderating effect on the relationship between death distress and quality of life among patients facing a life-threatening cancer diagnosis. The study sample consisted of 118 cancer patients: 82 cancer patients from a National Guard hospital in Saudi Arabia and 36 cancer patients from H. Lee Moffitt Cancer Center, Tampa, Florida. Three validated scales were used to obtain data from study participants: the Death Distress Scale, the Belief into Action Scale; and the Functional Assessment of Cancer Therapy Scale. After a Pearson correlation were conducted and results indicated a moderately strong inverse relationship between death distress and quality of life among both the Christian (r=-.45, p <.001) and Muslim (r=-.39, p <.001) patient samples. The degree of religiosity among study participants did not alter the effect of death distress on quality of life. Results reveal that the interaction term was not statistically significant (b=.005, p=.32). However, quality of life correlated with degree of religiosity in both the Christian(r=.39, p=.018) and Muslim patient groups ( r=.24, p=0.034)). This finding reinforces the importance of religious involvement among cancer patients found in earlier research. The current study highlights the importance of a holistic treatment approach that includes a spiritual component for these vulnerable individuals and their loved ones. This holistic emphasis is particularly important for nurses, who often spend more time with cancer patients than other health care professionals. By proactively discussing common issues surrounding death distress with patients and families, nurses can provide much needed education and emotional support and make appropriate referral. Given that death distress appears to be a nearly universal experience among cancer patients regardless of religious affiliation, future research should develop evidence-based nursing protocols to address this vital topic.

Cancer cells exhibit an abnormal metabolic phenotype characterized by glycolysis and lactate fermentation in the presence of oxygen, a phenomenon known as the Warburg effect. This dysregulated metabolism plays an important role in every aspect of cancer progression, from tumorigenesis to invasion and metastasis. The Warburg effect is a common phenotype shared by most, if not all, cancer types. It is especially prominent in metastatic tumors, which are notoriously resistant to treatment and responsible for the majority of cancer-related deaths. Thus, metabolic therapies which target the Warburg effect could offer novel therapeutic options for most cancer patients, including those with aggressive or late-stage cancers. The ketogenic diet is a high fat, low carbohydrate diet that induces a physiological state of nutritional ketosis - decreased blood glucose and elevated blood ketones. It has been investigated as a cancer therapy for its potential to exploit the Warburg effect by restricting glucose availability to glycolysis-dependent tumors, and has been reported to slow cancer progression in some animal models as well as in anecdotal reports and small clinical studies in humans. Interestingly, there is some evidence that the elevation in blood ketones induced by the ketogenic diet contributes to its anti-cancer effects, suggesting that ketone supplementation could possibly inhibit cancer progression on its own. Rapid growth outstrips a tumor's ability to adequately perfuse its tissue, creating regions of tumor hypoxia which exacerbate the Warburg effect and promote a malignant phenotype. Hyperbaric oxygen therapy is the administration of 100% oxygen at elevated barometric pressure. It supersaturates the blood with oxygen, increasing its diffusion distance into the tissues, and can therefore be used to increase intratumoral pO2 and reverse tumor hypoxia. Here we present evidence that the ketogenic diet, ketone supplementation, and hyperbaric oxygen therapy work individually and in combination to slow progression and extend survival in the VM-M3 model of metastatic cancer. This study strongly suggests that these cost effective, non-toxic metabolic therapies should be further evaluated in animal and human studies to determine their potential clinical use.