• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 161
  • 46
  • 42
  • 30
  • 18
  • 14
  • 8
  • 5
  • 3
  • 2
  • 2
  • 1
  • 1
  • 1
  • Tagged with
  • 438
  • 438
  • 68
  • 58
  • 57
  • 49
  • 37
  • 31
  • 31
  • 29
  • 29
  • 28
  • 26
  • 26
  • 25
  • 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.

Helplessness/hopelessness, minimization and optimism predict survival in women with invasive ovarian cancer: a role for targeted support during initial treatment decision-making?

Price, Melanie A, Butow, Phyllis N, Bell, Melanie L, deFazio, Anna, Friedlander, Michael, Fardell, Joanna E, Protani, Melinda M, Webb, Penelope M 06 1900 (has links)
Women with advanced ovarian cancer generally have a poor prognosis but there is significant variability in survival despite similar disease characteristics and treatment regimens. The aim of this study was to determine whether psychosocial factors predict survival in women with ovarian cancer, controlling for potential confounders.

Characterization of Residual Ovarian Tissue in Mice following 4-vinylcyclohexene Diepoxide-induced Ovarian Failure

Craig, Zelieann Rivera January 2009 (has links)
Menopause is associated with disorders such as osteoporosis and ovarian cancer. It is unclear whether the postmenopausal ovary retains steroidogenic capacity and how it can impact the development of these disorders. The present studies used the VCD-treated follicle-depleted mouse model of menopause to test the hypothesis that residual ovarian tissue retains steroidogenic capacity following ovarian failure and, thus, affects the development of these disorders. Microarray technology was used to evaluate gene expression in residual ovarian tissue of follicle-depleted mice compared to that in ovaries from cycling animals. Among the genes identified were those encoding proteins for synthesis of androgens. Steroidogenic capacity of residual ovarian tissue was further evaluated by determining the expression of genes and proteins involved in ovarian steroidogenesis, and by measuring levels of circulating and rostenedione and gonadotropins. Follicle-depleted ovaries were enriched in mRNAs for androgenic enzymes, receptors involved in the internalization of cholesterol, and luteinizing hormone receptor. Increased circulating levels of FSH and LH and detectable and rostenedione were measured throughout the study. Protein for 3β-hydroxysteroid dehydrogenase, 17α- hydroxylase/17,20-lyase and luteinizing hormone receptor was detected in follicledepleted ovaries by Western blot analysis and localized by immunofluorescence staining. The contribution of retaining residual ovarian tissue to accelerated bone loss following ovarian failure was evaluated by comparing bone mineral density from young and aged VCD-treated mice to that in age-matched ovariectomized (OVX) animals. Retaining residual ovarian tissue resulted in protection against accelerated bone loss in young but not aged VCD-treated mice. Whether residual ovarian tissue is more susceptible to development of ovarian neoplasms compared to ovaries from cycling animals was addressed by combining the VCD-treated mouse with the DMBA model of ovarian carcinogenesis. VCD-treated follicle-depleted mice that received DMBA developed Sertoli-Leydig cell tumors while no tumors were observed in cycling animals. Residual ovarian tissue following ovarian failure appears to have a protective effect against loss of bone integrity, but a detrimental effect on development of ovarian neoplasms. Findings from these studies: provided evidence of a physiological role for residual ovarian tissue following ovarian failure, and furthered the use of the VCD-treated mouse as a relevant model for menopause and associated disorders.

Pilot Study of Patient and Oncologist Preferences for Chemotherapy Treatment of Advanced Ovarian Cancer

Hess, Lisa M. January 2007 (has links)
Ovarian cancer is the leading cause of gynecologic cancer death among women in the United States, claiming the lives of more than 15,000 women each year. Women who receive this diagnosis must make rapid, critical medical decisions that impact survival and quality of life. Two studies were conducted to obtain pilot data related to the health preferences of ovarian cancer patients and their oncologists. Forty-one eligible patients and 34 eligible physicians participated in this study. Six hypothetical health states were developed based on possible outcomes of ovarian cancer treatment strategies. Participants were asked to rate these health states using a visual analog scale and the standard gamble chance board. A series of exploratory hypotheses were tested to obtain guidance for future research. Patients under surveillance had significantly lower preferences for all health states than patients receiving chemotherapy or physicians. Overall, patients were very consistent across health states with the level of risk they were willing to take, while physicians were significantly more likely to avoid risk when the treatment strategy presented involved improved treatment efficacy, even when associated with higher toxicity and poor emotional well being. These findings show the need for additional research and suggest that research in medical decision making must examine health choices made by patients separately, depending on their current treatment status, but not necessarily by current self-reported health status, time since diagnosis or by recurrent/non-recurrent disease.

Adhesion molecules in the interactions of ovarian tumour cells and mesothelial cells

Gardner, M. J. January 1996 (has links)
No description available.

Regulatory studies of the mammalian RNA polymerase III transcriptional apparatus

Allison, Simon J. January 2001 (has links)
No description available.

Genetic analysis of chromosome 17 in ovarian tumours and cell lines

Cranston, Aaron-Neill January 1996 (has links)
No description available.

The role of P53 in platinum anticancer drug sensitivity

Pestell, Katharine Elizabeth January 1999 (has links)
No description available.

An evaluation of cancer biomarkers in normal ovarian epithelial cells and ovarian cancer cell lines

Fruka, Tayra January 2019 (has links)
Philosophiae Doctor - PhD / Introduction: Globally, there are over 190,000 new reported cases of ovarian cancers per annum. This comprises 3% to 4% of all cancers in women. Ovarian cancer is one of the leading causes of deaths in women. Ovarian cancer is the second most diagnosed gynaecological malignancy and over all the fifth cause leading to death among all types of cancer in the UK in 2004. More than 70% of epithelial ovarian cancers are diagnosed at an advanced stage. Consequently, the prognosis is poor and the mortality rate high. Thus, the survival rate is affected by how far the disease has progressed or spread. A dire need exists to identify ovarian cancer biomarkers, which could be used as good indicators of expression in ovarian cancer cells in vitro Aim: The aim of this study was to analyse selected cancer biomarkers, which are currently under intense investigation for their suitability to diagnose epithelial ovarian cancer at an early stage. These biomarkers were analysed in terms of their in vitro expression in normal epithelial cells and ovarian cancer cell lines, which allows for their genomic and proteomic classification. The expression analysis of each biomarker is related to the malignancy of a tumour and, therefore, advocates its use for potential future improvement of sensitive tumour markers. Methods: The primary human ovarian surface epithelial cell line (HOSEpiC), SKOV-3 cells and the OAW42 human epithelial ovarian tumour cell lines were used to evaluate the selected cancer biomarkers. Cells were cultured using appropriate media and supplements, and real-time quantitative polymerase chain reaction (RT-PCR) utilized to validate expression levels of the following genes: HDAC1, HDAC2, HDCA3, HDAC5, HDAC6, HDAC7, HDAC8, LPAR1, LPAR2, MUC16 and FOSL1, against normal housekeeping genes GAPDH and HPRT. In addition, immunocytochemistry was also used in the validation process of the aforementioned genes. Significance: ovarian cancer cells express gene signatures, which pose significant challenges for cancer drug development, therapeutics, prevention and management. The present study is an effort to explore ovarian cancer biomarkers to provide a better diagnostic method that may offer translational therapeutic possibilities to increase five- year survival rate. Results: HDAC5, HDAC6, LPAR1, LPAR2 and MUC16 expressed distinctively in ovarian cancers matched to other tissues or cancer types have already been identified by RT-QPCR and confirmed by immunocytochemistry and efforts to generate monoclonal antibodies to the other six genes (HDAC1, HDAC2, HDAC3, HDAC7, HDAC8 and FOSL1) encoded proteins are underway. Conclusions: here we provide strong evidence suggesting that HDAC5, HDAC6, LPAR1, LPAR2, except MUC16 are up regulated in ovarian cancer. These data were confirmed by examining Human Protein Atlas (HPA) databases, in addition to protein expression of HDAC5, HDAC6, LPAR1, LPAR2 and MUC16 in cells cytoplasm. For future prospective, using other techniques that assess the variant expression that could explain the release of these gene candidates into the circulation with serum tumour markers, and protein expression will be strengthened.

Phosphoproteomic profiling and targeting of the PI3K/Akt/mTOR and MAPK pathways in ovarian cancer

Tashkandi, Ghassan Yousuf January 2017 (has links)
The PI3K/Akt/mTOR and MAPK pathways are frequently altered in ovarian cancer cells, making them potential candidates for targeted therapy. A more complete understanding of the complex interactions between the different proteins within the two pathways would assist in developing more effective treatment strategies to help overcome therapy resistance. The purpose of this project was to understand the phosphoproteomic changes in response to PI3K/mTOR inhibition in ovarian cancer cells and to identify potential mechanisms that may lead to targeted therapy resistance. To investigate the effect of inhibiting PI3K/mTOR at the cellular level in ovarian cancer, PI3K (LY294002), mTOR (rapamycin) and dual PI3K/mTOR (BEZ235) inhibitors were used to treat a panel of ovarian cancer cell lines. All tested cells, irrespective of PI3K/Akt/mTOR and MAPK pathways mutational status, responded to the three inhibitors. BEZ235 treatment produced greater cell inhibition than the monotargeted agents, while PTENmutated cell lines were more responsive to mTOR blockade than inhibition of PI3K alone. The phosphoproteomic changes in the cell lines were evaluated over a time course after treatment with the inhibitors, stimulated by heregulin, and studied using reverse phase protein array analysis. The results revealed that the decreased expression of pAkt (Thr308) appears to be a biomarker of sensitivity for LY294002 and BEZ235 in both PEO4 and A2780 cells, while upregulation of pAkt (Ser473) is an indicator for effective rapamycin treatment within the same cell lines. Increased pAkt (Ser473) expression after rapamycin treatment in PEO4 cells is believed to be due to the S6K1-mTORC2-Akt feedback loop. It was observed that pERK was upregulated upon BEZ235 treatment, which suggested the presence of cross talk between the PI3K/Akt/mTOR and MAPK pathways. A combination of BEZ235 and PD-0325901 (MEK inhibitor) treatments inhibited both pAkt (Ser473) and pERK, which also produced significant inhibition in cell proliferation compared to monotherapy treatment. The data also revealed a novel finding in ovarian cancer that prolonged (24h) treatment with rapamycin sensitises mTORC2 in PEO4 cells under heregulin stimulation. Moreover, network correlation and clustering analysis using the phosphoproteomic data identified significant correlations between the expression of pmTOR (Ser2481), and both p-cRaf (Ser259 and Ser338). Sin1 knockdown was performed in PEO4 cells and showed significant downregulation in the expression of pAkt (Ser473) and upregulation in pERK expression, indicating the role of Sin1 to regulate both the PI3K/Akt/mTOR and MAPK pathways potentially via mTORC2 and Ras. Phosphoproteomic profiling was performed on 469 ovarian cancer tissue samples using TMA and IHC analysis. Several significant associations were discovered between the phosphoproteomic data and the different clinicopathological parameters. High expression of pmTOR (Ser2448) was correlated with poorer overall survival in patients with ovarian endometrioid carcinoma compared to patients with low expression (p < 0.024). This implies that pmTOR (Ser2448) expression may potentially be a prognostic marker for patients with ovarian endometrioid carcinoma. In conclusion, I present dynamic phosphoproteomic profiling of the PI3K/Akt/mTOR and MAPK pathways in ovarian cancer, suggesting novel feedback loops and cross talk that could play a role in resistance mechanisms to these therapies. Combination treatment showed an additive effect on cell growth offering an approach to overcome drug resistance.

Characterisation of checkpoint kinase 1 and 2 in ovarian cancer

Francis, Kyle Evan January 2016 (has links)
CHEK1 inhibitors are currently in clinical trials for their ability to abrogate chemotherapy-induced CHEK1 activation and S phase arrest resulting in cancer cell apoptosis. No studies have yet identified ovarian cancers that could benefit from CHEK1-targeting therapy. I hypothesised that knowledge of CHEK1 and CHEK2 signalling in the DNA damage response can assist in identifying potential biomarkers for platinum responsiveness and CHEK-targeting therapy in ovarian cancer. In vitro studies investigated the CHEK1/2 inhibitor AZD7762 (AZD) and cisplatin (CP) in same patient-derived platinum-sensitive/resistant high-grade serous ovarian cancer cell lines (PEO1/PEO4 and PEO14/PEO23). Cytotoxicity assays confirmed higher CP IC50’s for PEO4 and PEO23 relative to PEO1 and PEO14 cell lines, respectively. AZD was more toxic to PEO1 cells and an additive effect of AZD with CP relative to CP alone was seen. A nontoxic AZD treatment to PEO4 cells sensitised the cells to CP when applied in combination. PEO14 and PEO23 cells had similar cytotoxicity profiles for combination treatments. BRDU DNA synthesis assays and cell cycle analysis revealed increased BRDU incorporation and accumulation in S phase when all cell lines were treated with CP. AZD treatment had a similar effect in PEO14 and PEO23 cells and increased the sub-G1 population, a marker of apoptotic DNA fragmentation, relative to control. Drug combination had no major effect on cell cycle distributions of both PEO14 and PEO23 cells relative to single agents but resulted in BRDU incorporation levels below CP and control levels for PEO14 cells. In PEO1 and PEO4 cells, AZD did not affect the cell cycle or DNA synthesis levels relative to control. Drug combination did not alter the cell cycle relative to CP treatment for PEO1 cells but decreased S phase and increased G2/M and sub-G1 populations in PEO4 cells. This was coupled with a decrease of CP-induced BRDU levels in PEO4 control levels. Apoptotic PARP cleavage/total PARP occurred early in CP treated PEO1 and PEO14 cells. A surrogate CHEK1/2 activity marker, p-CDC2 (Y15), decreased in all lines treated with AZD relative to control. Within PEO1 and PEO4 cells, greatest PARP cleavage was observed with combination treatment and coincided with high p-H2AX (S139), a DNA damage marker. p-CHEK1 (S317) and p-CHEK2 (T68), both ATR and ATM phosphorylation sites during DNA damage, increased for lone drug treatment and, to a greater extent, the combination drug treatments. PARP cleavage occurs across all treatments in PEO1 cells while it only occurs in the combination treatment for PEO4 cells. The latter coincides with a decrease in p-CHEK1 (S296) a CHEK1 autophosphorylation site, p-TP53 (S15), and p-BRCA1 (S1524), a homologous recombination marker, relative to the CP treated sample. In PEO14 and PEO23 cells, lone AZD and combination treatments had similar cleaved PARP/total PARP levels compared to the PEO14 CP treated cells. This was coupled with increased p-H2AX (S139), decreased CHEK1, and decreased CHEK2 autophosphorylation p-CHEK2 (S516). A human ovarian cancer xenograft model identified increases in p-H2AX (S139), CHEK1, p-CHEK1 (S317), p-CHEK2 (T68), and p-BRCA1 (S1524) in the carboplatin responsive cancers. In the paired pre- and post-chemotherapy human ovarian cancer samples, p-CHEK1 (S317) was elevated in post-chemotherapy responsive samples. In the first cohort, high p-CHEK1 (S317) was an independent poor overall survival biomarker and correlated with high p-H2AX (S139), MYC, p-CHEK1 (S296), p-CHEK2 (T68), p-CHEK2 (S516), and p-TP53 (S15). p-CHEK1 (S317) was associated with poor overall survival in serous ovarian cancers within the second pre-treatment ovarian cancer cohort. In conclusion, AZD can induce apoptosis in CP resistant cancer cells by synergising with CP to abrogate the S phase checkpoint, increase DNA damage, and inhibit CHEK1, and BRCA1 function. As a single agent, AZD can induce apoptosis by decreasing CHEK1 levels and CHEK2 activity. p- CHEK1 (S317) is a platinum responsive / poor prognostic biomarker.

Page generated in 0.1202 seconds