4 resultados para OVARIAN RESISTANCE
em QSpace: Queen's University - Canada
Resumo:
High-grade serous ovarian cancer (HGSC) is the most prevalent epithelial ovarian cancer characterized by late detection, metastasis and resistance to chemotherapy. Previous studies on the tumour immune microenvironment in HGSC identified STAT1 and CXCL10 as the most differentially expressed genes between treatment naïve chemotherapy resistant and sensitive tumours. Interferon-induced STAT1 is a transcription factor, which induces many genes including tumour suppressor genes and those involved in recruitment of immune cells to the tumour immune microenvironment (TME), including CXCL10. CXCL10 is a chemokine that recruits tumour infiltrating lymphocytes (TILs) and exhibits angiostatic function. The current study was performed to determine the effects of differential STAT1 and CXCL10 expression on HGSC disease progression and TME. STAT1 expression and intratumoural CD8+ T cells were evaluated as prognostic and predictive biomarkers via immunohistochemistry on 734 HGSC tumours accrued from the Terry Fox Research Institute-Canadian Ovarian Experimental Unified Resource. The combined effect of STAT1 expression and CD8+ TIL density was confirmed as prognostic and predictive companion biomarkers in the second independent biomarker validation study. Significant positive correlation between STAT1 expression and intratumoral CD8+ TIL density was observed. The effects of enforced CXCL10 expression on HGSC tumour growth, vasculature and immune tumour microenvironment were studied in the ID8 mouse ovarian cancer cell engraftment in immunocompetent C57BL/6 mice. Significant decrease in tumour progression in mice injected with ID8 CXCL10 overexpressing cells compared to mice injected with ID8 vector control cells was observed. Multiplexed cytokine analysis of ascites showed differential expression of IL-6, VEGF and CXCL9 between the two groups. Endothelial cell marker staining showed differences in tumour vasculature between the two groups. Immune transcriptomic profiling identified distinct expression profiles in genes associated with cytokines, chemokines, interferons, T cell function and apoptosis between the two groups. These findings provide evidence that STAT1 is an independent biomarker and in combination with CD8+ TIL density could be applied as novel immune-based biomarkers in HGSC. These results provide the basis for future studies aimed at understanding mechanisms underlying differential tumour STAT1 and CXCL10 expression and its role in pre-existing tumour immunologic diversity, thus potentially contributing to biomarker guided immune modulatory therapies.
Resumo:
Call centres have in the last three decades come to define the interaction between corporations, governments, and other institutions and their respective customers, citizens, and members. From telemarketing to tele-health services, to credit card assistance, and even emergency response systems, call centres function as a nexus mediating technologically enabled labour practices with the commodification of services. Because of the ubiquitous nature of the call centre in post-industrial capitalism, the banality of these interactions often overshadows the nature of work and labour in this now-global sector. Advances in telecommunication technologies and the globalization of management practices designed to oversee and maintain standardized labour processes have made call centre work an international phenomenon. Simultaneously, these developments have dislocated assumptions about the geographic and spatial seat of work in what is defined here as the new international division of knowledge labour. The offshoring and outsourcing of call centre employment, part of the larger information technology and information technology enabled services sectors, has become a growing practice amongst governments and corporations in their attempts at controlling costs. Leading offshore destinations for call centre work, such as Canada and India, emerged as prominent locations for call centre work for these reasons. While incredible advances in technology have permitted the use of distant and “offshore” labour forces, the grander reshaping of an international political economy of communications has allowed for the acceleration of these processes. New and established labour unions have responded to these changes in the global regimes of work by seeking to organize call centre workers. These efforts have been assisted by a range of forces, not least of which is the condition of work itself, but also attempts by global union federations to build a bridge between international unionism and local organizing campaigns in the Global South and Global North. Through an examination of trade union interventions in the call centre industries located in Canada and India, this dissertation contributes to research on post-industrial employment by using political economy as a juncture between development studies, critical communications, and labour studies.
Resumo:
Performing Resistance/ Negotiating Sovereignty: Indigenous Women’s Performance Art In Canada investigates the contemporary production of Indigenous performance and video art in Canada in terms of cultural continuance, survivance and resistance. Drawing on critical Indigenous methodology, which foregrounds the necessity of privileging multiple Indigenous systems of knowledge, it explores these themes through the lenses of storytelling, decolonization, activism, and agency. With specific reference to performances by Rebecca Belmore, Lori Blondeau, Cheryl L'Hirondelle, Skeena Reece and Dana Claxton, as well as others, it argues that Indigenous performance art should be understood in terms of i) its enduring relationship to activism and resistance ii) its ongoing use as a tool for interventions in colonially entrenched spaces, and iii) its longstanding role in maintaining self-determination and cultural sovereignty.
Resumo:
Abnormal maternal inflammation during pregnancy is linked to complications such as preeclampsia and fetal growth restriction. There is growing evidence that insulin resistance is also associated with a heightened inflammatory state, and is linked to pregnancy complications such as gestational diabetes. This study tested the hypothesis that abnormal inflammation during pregnancy is causally linked to elevations in blood glucose and insulin resistance. To induce a state of abnormal systemic inflammation, bacterial lipopolysaccharide (LPS) was administered to pregnant rats on gestational days (GD) 13.5-16.5. Dams treated with LPS exhibited an abnormal immune response characterized by an elevation in white blood cells, which was linked to reduced fetal weight and increased glucose levels over pregnancy. Abnormal inflammation is characterized by increased levels of circulating pro-inflammatory cytokines such as tumour necrosis factor alpha (TNF) and interleukin-6, which contribute to insulin resistance by inhibiting the insulin signalling pathway. TNF in particular induces a serine phosphorylation (pSer307) of insulin receptor substrate 1 (IRS-1). In our model, insulin resistance was assessed by measuring the extent of pSer307 of IRS-1 and total IRS-1 expression in skeletal muscle, as well as changes in metabolic parameters and pancreas tissue morphology associated with insulin resistance. LPS-treated dams exhibited a significant reduction in IRS-1 expression, elevation in fasting glucose levels, and reduction in insulin sensitivity indices. There were also biologically relevant increases in fasting plasma insulin levels and insulin resistance indices, but not pSer307 of IRS-1 and pancreatic islet size. To determine whether inflammation plays a role in reducing insulin signalling and the other changes associated with LPS administration, etanercept, a TNF antagonist, was administered on GDs 13.5 and 15.5 prior to LPS injections. With the exception of IRS-1 expression, in rats treated with etanercept all of the measured parameters remained at the levels observed in saline controls, indicating a link between abnormal inflammation and insulin resistance. The results of this study support the practice of monitoring the inflammatory conditions of the mother prior to and during pregnancy, and support further investigation into the potential use of anti-inflammatory agents during pregnancy in women at risk of insulin resistance and gestational diabetes.