A crucial requirement for the stepwise, continued growth of a brain tumor is the acquisition of a blood supply from the host, i.e. angiogenesis. The mechanisms of copper activity linked to neovascular and neoplastic growth are largely unknown. Copper ion was shown to be a cofactor for angiogenesis. / We tested the effect of copper depletion achieved by a low copper diet and a copper chelator D-penicillamine, on the intracerebral growth of two experimental brain tumors. We developed in in vivo brain tumor model using the VX2 carcinoma. Implantation of 5 $ times$ 10$ sp5$ VX2 carcinoma cells into the parietal lobe of normocupremic rabbits consistently yielded large hemorrhagic, necrotic, vascularized tumors. The cortical surface revealed numerous, hypertrophied, tortuous new vessels with feeding arteries and draining veins similar to the angioarchitecture of malignant human brain tumors. We report here that copper depletion prevents tumor neovascularization and restricts tumor growth of the VX2 carcinoma in the rabbit brain. Low copper diet and penicillamine are both necessary to achieve angiogenic inhibition. We also tested the effect of copper depletion on the 9L gliosarcoma. We observed that invasive growth of the tumor was blocked in rats depleted of copper. Electron microscopy revealed the absence of cytoplasmic extensions, including pseudopodia, by contrast, in normocupremic controls, cytoplasmic extensions, typical of mobile cells, invaded the surrounding neuropil. Our findings link the activity of copper in vascular and neoplastic growth. / We found an increase in the peritumoral brain water content in the copper depleted animals and that copper depletion by itself in nontumor implanted animal has no effect on brain water content. / Because of the ability to pharmacologically suppress capillary growth induced by the VX2 carcinoma, we could test the relative contribution of breakdown of the blood-brain barrier compared with that of angiogenesis in the appearance of contrast enhancement in computed tomographic examinations. We conclude from our data that tumor neovascularization, in our brain tumor model, is the key determinant for the appearance of contrast enhancement. / The same protocol used in the brain failed to prevent tumor neovascularization and growth of the VX2 carcinoma in the muscle of the rabbit thigh indicating the crucial role played by the milieu (muscle versus brain) for the growth of malignant tumor. In the same manner, lung metastases were not prevented.

Breast cancer is a heterogeneous disease comprised of distinct biological entities that correlate with diverse clinical outcomes. Gene expression profiling has divided this heterogeneity into luminal, ERBB2+ and basal molecular subtypes. Basal breast cancers are difficult to treat as they lack expression of candidates suitable for targeted therapies and are associated with poor outcome. / Elevated protein level of the hepatocyte growth factor receptor, MET, is observed in 20% of human breast cancers and correlates with poor prognosis. However, the role of MET in mammary tumorigenesis is poorly understood. To address this, we generated a murine model that expresses weakly oncogenic mutants of Met (Metmt) in the mammary epithelium under the transcriptional control of the mouse mammary tumor virus promoter. We demonstrate that Metmt induces mammary carcinomas with diverse phenotypes and used gene expression microarrays to elucidate gene expression changes induced by Met. Since mammary tumors contained variable contents of epithelium and stroma, we used laser capture microdissection to procure epithelial cells for microarray analysis. Based on immunohistochemistry and expression profiling, we show that Metmt produces tumors with luminal or basal characteristics. From hierarchical clustering, Metmt-induced basal tumors clustered with murine models that share features of epithelial to mesenchymal transition and human basal breast cancers. Moreover, Metmt basal tumors clustered with human basal breast cancer. The status of MET among the human breast cancer subtypes has not previously been addressed. We demonstrate that MET levels are variable across molecular subtypes but show elevation in the basal subtype and correlates with poor outcome. We used a candidate gene approach derived from microarray data to gain an understanding of signals required for Met-dependent tumorigenesis. We investigated Nck adaptor proteins and demonstrate a role for Nck in cell motility and actin dynamics of Met-dependent breast carcinoma cells and show elevated expression in human basal breast cancers. By generating a unique mouse model in which Met is expressed in mammary epithelia, with the examination of MET levels in human breast cancer, we have established a novel link between MET and basal breast cancer. This work identifies poor outcome basal breast cancers that may benefit from anti-MET therapies.

Es tracta d'un estudi epidemiològic de les neoplàsies limfoides a Tarragona. Es donen dades d'incidència, mortalitat, supervivència i prevalença en base poblacional de les 3.258 neoplàsies limfoides del Registre de Càncer de Tarragona durant el període 1980-2004 ( 354 limfomes de Hodgkin, 1605 limfomes no-Hodgkin (LNH), 676 mielomes múltiples, 188 leucèmies limfàtiques agudes i 435 leucèmies limfàtiques cròniques). S'ha estudiat la tendència temporal de la incidència i la seva projecció a 2010 i 2015 per a cada grup de malalties. Els LNH s'han classificat histològicament d'acord amb la classificació de l'OMS de les neoplàsies hematològiques, i s'han establert comparacions internacionals. Les principals conclusions han estat que les neoplàsies limfoides a Tarragona mostren un patró epidemiològic occidentalitzat, amb una progressiva millora en la seva supervivència relativa, i que existeix, almenys parcialment, una relació temporal entre la epidèmia de la SIDA i la dels LNH. / This is an epidemiological study of lymphoid neoplasms in Tarragona, a southern region of Catalonia with a population over 800.000. It gives details of incidence, mortality, survival and prevalence in a population basis of 3,258 lymphoid malignancies recorded in the Tarragona Cancer Registry during the period 1980 to 2004 (354 Hodgkin's lymphoma, 1605 non-Hodgkin's lymphoma (NHL), 676 multiple myeloma, 188 acute lymphocytic leukemia and 435 chronic lymphocytic leukemia). We have studied the incidence time trend and its projection to 2010 and 2015 for each disease group. The NHL were classified histologically according to WHO classification of hematologic malignancies, and their relative frequency were compared internationally. The main conclusions were that the lymphoid malignancies in Tarragona show a westernized epidemiological pattern, with a progressive improvement in their relative survival and that there is at least partially, a temporal relationship between the AIDS and the NHL epidemics.

Background: The relative treatment effectiveness of surgery versus radiotherapy for early-stage prostate cancer is uncertain and randomized clinical trials are unlikely to be performed. This study describes the difference in cause-specific survival between patients treated with radiotherapy versus surgery, using a number of design and analytic steps to mitigate confounding by indication within an observational study. Methods: We conducted a population-based case-cohort study, sampling patients from the Ontario Cancer Registry who were treated or were candidates for cure by radiotherapy or surgery. Cases were those who died of prostate cancer within 10 years. Cause-specific survival was analyzed using Cox-proportional hazard regression, with variance adjustment for the case-cohort sampling. Analysis using intent to treat was compared to that using treatment received. Propensity scores were also calculated and Cox-proportional hazard regression was conducted within each propensity score quintile. We formed instrumental variable groups based on radiotherapy rates in Cancer Care Ontario Regions (CCORs) using the study population sampling frame and checked the instrumental variable assumption of equal distribution of covariates by comparing those covariates across these groups using data from the subcohort. Results: The adjusted hazard ratios for risk of prostate cancer death for radiotherapy compared to surgery were 1.44 (95% CI 0.86-2.40) and 1.84 (1.06-3.17) using intent to treat and treatment received respectively. Stratified hazard ratios comparing radiotherapy to surgery for death from prostate cancer from the lowest propensity quintile to the highest propensity quintile were 0.30 (0.04-2.28), 1.54 (0.35-6.77), 0.90 (0.29-2.82), 2.71 (1.01-7.31) and 1.08 (0.41-2.81). Differences among these hazard ratios were not statistically significant (p=0.13). The distributions of all prognostic indicators were statistically significantly different between instrumental variable groups. Conclusion: Analysis by intent to treat produced a hazard ratio closer to the null than analysis by treatment received, indicating that uncontrolled confounding toward more serious cases getting radiotherapy was present in the analysis by treatment received. Future studies should focus on obtaining enough numbers for subgroup analysis such as the stratification by risk groups. Caution should be used when using the instrumental variable approach in this population, as prognostic indicators were not as equally distributed as expected. / Thesis (Master, Community Health & Epidemiology) -- Queen's University, 2009-09-24 17:54:09.955

Background: Life expectancy (LE) estimation is an important part of both screening and treatment decision-making for potentially curable prostate cancer. Clinicians’ estimation of patient life expectancy is typically made using population-based life tables and intuition and it is often inaccurate. This study explores methods to improve LE prediction by formally considering patient co-morbid illness status, in addition to age, in the development of a LE prediction tool. Methods: We conducted a population-based retrospective cohort study of patients from the Ontario Cancer Registry who were curative treatment candidates, identified between 1990-1998. We analyzed data on three sub-populations of this cohort, and we used LE estimates from the Ontario Life Tables. Each model utilized Cox proportional hazards analysis, and/or the declining exponential approximation of LE, to estimate the survival experience of potential curative treatment candidates, including the impact due to both age and co-morbid illness status. We developed five separate models, tested them using a random subset of the cohort study sample, and compared their predictive accuracy by measuring both discriminative ability and calibration to determine the ‘best’ model. We also conducted a supplementary analysis using logistic regression to develop a model to predict the probability of 10-year survival. Results: The ‘best’ of our models demonstrated a c-index of 0.65 and very good calibration. Further analysis revealed that our ‘best’ model violated the Cox PH assumption for age and it’s predictions consistently over-estimated observed LE. Supplementary analysis of the logistic regression prediction model demonstrated a c-index of 0.70. Conclusions: Our exploration of methods to predict LE resulted in modest predictive accuracy. However, based on the results of the logistic regression model, we conclude that the results of our LE prediction models are reasonable, and obtaining a high level of predictive accuracy may not be possible given just age and co-morbidities as predictors. Further studies should continue to explore these and other methods for LE prediction. External validation of the ‘best’ model from the current study is required before the model and its accompanying LE reference tables can be recommended for use in a clinical setting for screening or treatment decision-making. / Thesis (Master, Community Health & Epidemiology) -- Queen's University, 2011-04-07 19:11:34.216

Human papillomavirus (HPV) infections play a crucial role in human carcinogenesis. Greater than 96% of all cervical carcinomas are positive for high-risk HPV infections; especially types 16 and 18. High-risk HPV onco-proteins, E6 and E7, are consistently expressed in such cancers and function by inactivating p53 and pRb tumor suppressors, respectively. The presence of high-risk HPVs is also correlated with anogenital cancers. In this study, we examined the effect of high-risk HPV type 16 E6 and E7 oncoproteins in two normal human colorectal epithelial cell lines, NCE1 and NCE5. We report that the expression of E6/E7 proteins, alone, induced cellular transformation of both cell lines; consequently, NCE1-E6/E7 and NCE5-E6/E7 form colonies in soft agar with respect to their wild type cells. This is accompanied by cell cycle deregulation, as is demonstrated by the over-expression of cyclin dependant kinases (cdks) and their respective cyclins. Furthermore, we demonstrate that E6/E7 oncoprotein transduction induces migration of colorectal epithelial cells. More still, well analyzed Id gene expression, a family member of the helix-loop-helix (HLH) transcription factors involved in the regulation of cell invasion and metastasis of human cancer cells. In parallel, using tissue microarray analysis we found that the four members of the Id protein family are correlated with the presence of HPV type 16 and 18 in human colon cancer tissues. Our data suggests that high-risk HPV infections are sufficient to induce cellular transformation of normal human colorectal cells, in vitro. Furthermore, the correlation with the Id family of proteins may present a novel set of markers associated with HPV induced colorectal carcinogenesis. Our results may suggest a new approach to detect and prevent colorectal cancer.

Background: Traditionally, coping and decision making have been viewed as separate concepts. However, analysis of the role of emotions during decision making in healthcare suggests that coping with health threats, and associated emotions, should be viewed as an integral part of deliberation processes. This thesis reports on the development of a framework that merges deliberation and coping processes. Subsequently, this framework is operationalised by adapting it to specifically describe deliberations about risk-reducing salpingo-oophorectomy (RRSO) by women at increased genetic risk of ovarian cancer. Methods: A narrative review of the literature on decision making and coping theories informed the development of a novel framework that integrates theories from both fields. A multi-methods approach, which included a systematic literature search and qualitative methods, examined women’s decision making about RRSO and informed adaptation of the framework to specifically describe such decisions. The adapted framework was then used to develop a decision support intervention for women at increased risk of ovarian cancer in the UK. Incremental prototypes of the intervention were reviewed by a group of stakeholders and usability of the final prototype was tested using cognitive interviews. Results: The Coping in Deliberation (CODE) framework describes deliberations as multi-step appraisal and coping processes. The framework was successfully adapted to decisions about RRSO and used to develop a two part patient decision support intervention, consisting of a brief paper-based tool (Option Grid) and a longer website (the Oophorectomy Decision Explorer, OvDex). Conclusions: Emotions and coping are integral parts of deliberations in healthcare and the CODE framework, which acknowledges the importance of these concepts during deliberations, can be used to guide the development of patient decision support interventions. Future research should apply this framework to other healthcare decisions. The intervention developed in this thesis requires field testing to assess its impact before implementation in clinical practice.

Despite recent advances in the clinic to integrate novel targeted therapeutic agents into standard therapy, colorectal cancer (CRC) remains a significant cause of mortality. The high attrition rate of novel compounds at phase III clinical trials for CRC, has been attributed to limited information from pre-clinical strategies, in particular, the use of inadequate xenograft models. In response, this thesis aimed to utilise robust and relevant genetically engineered mouse models of CRC to evaluate a number of novel therapeutic strategies. Whilst mutations in the tumour suppressor APC are crucial for initiation of CRC, mutations which lead to activation of the PI3K and MAPK signalling pathways, such as through loss of the tumour suppressor protein PTEN and activation of oncogenic KRAS, have been implicated in promoting progression of CRC. As such, combinations of these genetic alterations within the murine intestine, using the Cre-LoxP system, lead to differing mouse models of invasive intestinal adenocarcinoma. This thesis reports therapeutic targeting of the PI3K and MAPK signalling pathways using the dual PI3K and mTOR inhibitor NVP-BEZ235, and the MEK inhibitor MEK162, respectively. For this, compounds were initially evaluated for pharmacodynamic and anti-tumour effects through short term exposure experiments. These analyses yielded a range of effects, some of which appeared predictive of long term efficacy, others which were contradictory and some which revealed novel feedback mechanisms. Furthermore, these agents were assessed in a long term therapeutic setting to evaluate the effect of continuous treatment on longevity and tumour burden of tumour models. Here, whilst dual PI3K/mTOR inhibition significantly increased longevity of all mouse models, MEK inhibition was only effective in the Apc and Apc Kras mutant settings, identifying Pten loss as a marker of non-response to MEK inhibition, independently and also in the Kras mutant setting. Furthermore, analysis of the combination therapy in short term settings identified scheduling of these agents to be key to achieve concomitant pathway inhibition, particularly in the Apc Pten deficient tumour setting. Ultimately, when evaluated in a long term setting, although the combination therapy displayed no further benefit in the Pten deficient setting, this had additive benefits in the Kras mutant setting and synergistic benefits in the Pten Kras mutant setting. Nevertheless despite the promise of targeted therapy, standard chemotherapeutic agents such as 5-flurouracil (5-FU) remain the backbone of therapy for CRC, regardless of only moderate benefits of 10-15% in advanced tumour settings. Furthermore, resistance to 5-FU predominantly through upregulation of the enzyme thymidylate synthase (TS) frequently 2 occurs in human tumours. Investigations reported here aimed to target tumours with upregulated TS using novel analogues of the anti-viral agent Brivudin (BVDU), metabolites of which are converted to anti-cancer metabolites by TS. Initially, In vitro characterisation of a small library of compounds reported here identified a number of potent compounds. Following further in vitro characterisation and short term evaluation in the Apc Pten tumour model of invasive adenocarcinoma, two lead compounds: CPF472 and CPF3172 were taken forward for long term experiments. Subsequently, this study evaluated and identified compounds which showed increased efficacy in the TS upregulated setting. Taken together, the investigations presented in this thesis highlight the utility of appropriate mouse models in evaluating novel therapeutic strategies and generating clinically relevant hypotheses.

The Myelodysplastic syndromes (MDSs) are comprised of a heterogeneous group of clonal disorders characterised by ineffective haematopoiesis. Although 30 to 35% of MDS cases progress to Acute Myeloid Leukaemia (AML), the majority of patients die from blood related ailments caused by progressive bone marrow failure. Large-scale genomic rearrangements are a key feature of MDS, with different aberrations conferring specific risks of progression. Telomere erosion, dysfunction and fusion, creating cycles of anaphase bridging breakage and fusion is a mechanism that has the potential to drive genomic instability in many tumour types including MDS. The key aim of this project was to examine the role that telomere dysfunction may play in the generation of genomic rearrangements observed in MDS/AML. High resolution Single Telomere Length Analysis (STELA) revealed telomere shortening when compared to age-matched individuals in two cohorts of MDS and AML patients; this included large-scale telomeric deletion events observed within the MDS cohort. A PCR based telomere fusion assay detected telomere-telomere fusion events at a frequency that was consistent with sporadic fusion arising as a consequence of large-scale deletion. Telomerase activity was up-regulated in AML which may contribute to the reduction of deletion and fusion events in these cells. Sequence analysis revealed that telomere fusion was associated with microhomology and sub-telomeric deletion; this profile was consistent with error-prone Ku-independent alternative end joining processes. Telomere length at diagnosis irrespective of conventional markers appeared to influence the overall survival of MDS patients, but this was not apparent in AML. More importantly, telomere length was able to refine favourable prognostic markers, specifically good risk cytogenetics, uni-lineage cytopenia and low-risk IPSS (International Prognostic Scoring System) scores of which MDS patients bearing shorter telomeres for their respective age displayed reduced overall survival. This may be a particularly important finding given the heterogeneous clinical outcomes observed within low-risk MDS patients.

Kiss-1 and its receptor (Kiss-1R) are suggested as a novel pair of metastasis suppressors for several human solid tumours. However, the role of Kiss-1 and Kiss-1R in colorectal cancer remains largely unknown. Therefore, the aim of this study was to investigate the role and signal transduction of Kiss-1 and its receptor in colorectal cancer. Colorectal cancer cell lines (HT115, HRT18, RKO and Caco-2) were screened for the mRNA expression levels of Kiss-1 and Kiss-1R. Sublines of cancer cells with differential expression of Kiss-1 and Kiss-1R were created, using ribozyme transgenes to knock down the expression of Kiss-1 and Kiss-1R, respectively. The stabilized transfected cells were used to study the influence of Kiss-1 and Kiss-1R on the function of colorectal cancer cells using by in vitro function assays (growth, adhesion, wounding and invasion assays) and ECIS assay. The influence of Kiss-1 on tumour growth was also tested using an in vivo tumour model. To further explore the receptor activation and signalling pathways downstream of Kiss-1, Kisspeptin-10 was also used in HT115 Kiss-1 knockdown cells. Phosphorylation of Kiss-1 and the effect of Kissthe effect on MMP 1 on MMP 1 on MMP-9 and MMP and MMP -2 were detected using immunoprecipitation and immunoprecipitation and zymographyzymography respectively. The study also investigated Kiss-1 and Kiss-1R expression and their correlation to the clinical outcome in human colorectal cancer, using real-time PCR and immunohistochemistry. Kiss-1 and Kiss-1R played a suppressive role in the invasion and migration of colorectal cancer cells, in that knocking down both Kiss-1 resulted in increased cell-matrix invasion and cellular migration as demonstrated by a series of cell models. Exogenous Kiss-1 (Kisspeptin-10) decreased cellular migration of colorectal cancer cells and required ERK signalling as shown during the ECIS based analyses. The inhibitory influence of Kiss-1 on the motility of cancer cells was via the reduction of MMP-9, shown by zymography. In the in vivo tumour model, tumour growth rate of Kiss-1 knockdown colorectal cancer cells was significantly faster than the control cells. In human colorectal cancer tissues, levels of message expression of Kiss-1 had a negative correlation with Dukes staging, TNM staging, tumour size and lymph node involvement. Kiss -1R expression was significantly decreased in tumour tissues compared with adjacent normal tissues. The present study has demonstrated that Kiss-1 and Kiss-1R play a pivotal tumour suppressor role in colorectal cancer. The inhibitory effect on cancer cells involves the regulation of MMPs and the ERK signaling pathway. The molecule pair is candidate prognostic indicator in patients with colorectal cancer.