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  • 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.
31

Transgenerational inheritance of increased breast cancer risk in mouse offspring of dams exposed to high fat N-6 polyunsaturated fatty acid diet during pregnancy

Nguyen, Nguyen M. 08 April 2017 (has links)
<p> Maternal high fat (HF) intake before and/or during pregnancy increases female offsprings&rsquo; mammary cancer risk in several preclinical models. Here I studied if maternal HF intake during pregnancy cause transgenerational increase in mammary cancer risk, and if the increase is reversible by treating adult offspring with inhibitors of histone deacetylases (HDAC) or DNA methyltransferases (DNMT).</p><p> Pregnant C57BL/6NTac mice were fed either a diet high in n-6 polyunsaturated fatty acids (HF) or control diet (CON). HF diet was given from gestational day (GD) 10 &ndash; 20 to target fetal primordial germ cell formation and differentiation to germ cells. Offspring in subsequent F1-F3 generations were only fed CON diet. Mammary tumor incidence, induced by 7,12-dimethylbenz[a]anthracene (DMBA), was significantly higher in F1 and F3 HF offspring, than in the controls. Tumor latency was shorter and burden higher in F1 HF, with similar trends, though not statistically significant, in F3 HF.</p><p> RNA-sequencing of normal mammary glands revealed 1587 and 4423 differentially expressed genes between HF and CON offspring in F1 and F3, respectively, of which 48 genes were similarly altered in both generations. Ingenuity Pathway Analysis identified genes associated with Notch signaling as key alterations in HF mammary glands. Knowledge-fused Differential Dependency Network analysis identified 10 node genes in HF offspring uniquely connected to genes linked to increased cancer risk, therapy resistance, poor prognosis, and impaired anti-cancer immunity.</p><p> Next, I studied whether HDAC and DNMT inhibitor treatment in adulthood of the offspring, prior to tumor formation, could reverse the increased mammary cancer risk caused by <i>in utero</i> HF exposure. CON and HF offspring were given valproic acid and hydralazine in drinking water (epi-treatment), starting one week after tumor initiation by DMBA. Epi-treatment significantly decreased tumor burden in HF offspring, potentially through reactivation of silenced tumor suppressors <i>CLCA1</i> and <i>CDKN2A</i>, but adversely affected CON offspring. These adverse effects were linked to upregulation of PERK, p62 and HIF-1&alpha; in CON.</p><p> In summary, maternal HF intake during pregnancy induced transgenerational increase in offsprings&rsquo; mammary cancer risk, causes persistent changes in the expression of genes linked to increased breast cancer risk, and epi-treatment in adulthood may reduce this risk.</p>
32

Basal-like breast cancer: modeling its initiation and characterizing novel EGFR variants

Pires, Maira Moura January 2012 (has links)
Breast cancer (BC) is now a disease that will affect 1 out of every 8 women worldwide. Due to its highly heterogeneous nature, BC is usually further classified into different subtypes according to gene expression profiling analysis. Basal-like breast cancer (BBC) accounts for 15-20% of all cases of BC. BBC is very aggressive, highly metastatic, and often lethal, mostly due to our poor understanding of the key genetic events that lead to the onset and/or maintain this subtype of BC. As a result, we currently lack targeted therapies that are otherwise very effective in some of the better understood subtypes of BC. Therefore we set to work on deciphering the genetic alterations that when, expressed altogether, would model the onset of sporadic BBC in human cell lines. We already know that patients with BBC often display mutations in the tumor suppressor p53, as well as over-expression of the epidermal growth factor receptor (EGFR) protein by immunohistochemistry, and that loss of PTEN protein is also seen occurring along with the aforementioned lesions. However, there is no model for sporadic BBC that accurately reflects the genetic changes that BBC tumor samples display for studying this BC subtype progression and/or providing a base for which pharmacological studies can be done to find an effective therapy. Thus we used a non-transformed immortalized mammary epithelial cell line, MCF10A, as our model and engineered cells with termed 'triple modified' cells that express the three aforementioned alterations (PTEN, EGFR, p53) that highly observed in BBC. Furthermore, as part of the goal to better understand the genetic underpinnings that occur in BBC progression, we investigated whether variant forms of EGFR existed in cell lines of the basal-like subtype. Prior studies have demonstrated that immunostaining for EGFR in BBC patient tumor samples is elevated, though the molecular mechanisms are not well understood. EGFR is only amplified in BBC in less than 1% of cases thus gene amplification does not account for the high percentage of tumors that express and overexpress EGFR. In the pursuit to better understand the possible contribution of deregulated EGFR in BBC, we discovered a variety of basal-like breast cancer lines containing genetic alterations in EGFR not yet reported in the literature and demonstrated that a portion of them stimulate growth, invasion and transformation in mammary cells. In conclusion, the studies on modeling basal-like tumorigenesis and identifying and characterizing novel variants of EGFR in basal-like breast cancer lines have shed new exciting insights into our current knowledge of BBC. Having a cell line model for the disease provides a new tool for which further genetic and epigenetic manipulations can be exercised to continue asking questions of which other oncogenes and tumor suppressors are important for initiation of BBC. Our data showing that EGFR variants can be found in BBC cell lines and alter breast epithelial growth shows that this is an area that should be further investigated in human tumors so that targeted therapies can be designed to improve patient survival rates and their quality of life.
33

Dietary Intake among Children with Acute Lymphoblastic Leukemia (ALL)

Ladas, Elena January 2013 (has links)
Children with acute lymphoblastic leukemia (ALL) are at elevated risk for nutrition-related morbidities both during and after therapy. The degree to which dietary intake fluctuates during cancer therapy and possibly contributes to the development of nutrition-related morbidities is unknown. This study presents the results of the first prospective study describing changes in dietary intake in 667 children undergoing treatment for ALL. Dietary intake was evaluated with a food frequency questionnaire at three timepoints reflecting different intensities of cancer therapy: diagnosis (Time 1-no therapy), induction (Time 2- high-dose therapy), and continuation (Time 3- low-dose therapy). Dietary intake was compared to the Dietary Reference Intakes (DRIs) and normative data. Contrary to expectations, total caloric intake in the majority of patients exceeded the DRIs with a smaller percentage of patients below the DRI for calories. The majority of patients were within the DRI for all other macronutrients with an increase in intake of fat at Time 2. Despite adequate caloric intake, the majority of patients had low dietary intakes of calcium, vitamin D, and vitamin E while excess dietary intakes were observed for zinc and niacin. For folate, most patients were either below or above the DRI. In general, dietary intakes were reflective of normative data suggesting intakes are not significantly altered during treatment for ALL. This study was successful in identifying priority nutrients for dietary intervention and scientific inquiry. The effect of these strategies on the development of nutrition-related morbidities in children with ALL may be considered for future research initiatives.
34

Contributions of Activated Hepatic Stellate Cells to Hepatocarcinogenesis

Dapito, Dianne Helerie January 2015 (has links)
Hepatocellular carcinoma (HCC), the second leading cause of worldwide cancer mortality, develops almost exclusively in patients with chronic liver disease. Approximately 90% of HCCs arise in fibrotic livers suggesting that wound healing contributes to HCC development. Despite this strong association, it is not known whether fibrosis actively contributes to HCC development. Here, we investigate the hypothesis that activated hepatic stellate cells (HSCs), the primary source of hepatic myofibroblasts, contribute to hepatocarcinogenesis. In a first study, we demonstrate that the intestinal microbiota and Toll-like receptor 4 (TLR4) promote hepatocarcinogenesis. Activation of TLR4 on activated HSCs triggered the secretion of the hepatomitogen epiregulin and epiregulin-dependent promotion of hepatocarcinogenesis. Non-absorbable antibiotics reduced HCC development, even when given at late stages of hepatocarcinogenesis, suggesting that targeting the intestinal microbiota-TLR4 pathway represents a novel therapeutic approach for HCC prevention. In a second study, we tested the hypothesis that extracellular matrix production by activated HSCs contributes to a tumor-prone hepatic microenvironment. We generated a novel genetic model of selective HSC activation that allows investigating functional links between fibrosis and HCC development without confounding injury, inflammation and regeneration common to most fibrosis models. We provide functional evidence that HSC activation and liver fibrosis actively promote hepatocarcinogenesis, as evidenced by a five-fold increase in tumor burden in mice with genetically-induced HSC activation. Taken together, our studies implicate activated HSCs in the promotion of HCC through inflammatory and non-inflammatory signaling pathways, and suggest that HSCs should be considered a possible target for HCC prevention strategies.
35

Impact of Telephone Call on Patient Satisfaction in Adult Oncology Patients

Frazier-Warmack, Victoria Maria 01 January 2017 (has links)
Patient satisfaction is an ongoing action in which hospitals and health care providers are constantly seeking strategies to improve their satisfaction ratings. In the ambulatory oncology infusion setting, patient satisfaction is also a key metric that is being monitored, but actual patient satisfaction is unknown. Guided by Lewin's change theory and King's theory of goal attainment, the aim of this project was to use a strategy of conducting follow-up telephones calls to determine if patient satisfaction improved in an ambulatory oncology setting. A descriptive comparative approach was used to evaluate patient satisfaction before and after a telephone follow-up intervention. Participants who were starting an initial or new chemotherapy protocol were randomized into the telephone follow-up (TFU) group or the control group. A TFU script was used to guide the telephone conversation with patients about their experience with the first chemotherapy visit. All participants (N= 62) completed the OUT-PATSAT 35 questionnaire before starting their chemotherapy and 72 hours after the chemotherapy. Demographic characteristics of participants did not differ from the general cancer population. T tests were used to determine whether satisfaction differed between the two groups and revealed that participants receiving the TFU had significantly greater satisfaction in all domains post treatment, compared to those who did not (t = 2.90, df = 15, p = .01), suggesting the TFU had a positive effect on patient satisfaction. Incorporating follow-up telephone calls as a standard of practice to persons receiving an initial or new chemotherapy protocol may contribute to improved patient satisfaction scores and positive social change through an improved sense of well-being in cancer patients.
36

Alterations in the PI3K/AKT Signaling Pathway and Response to Adjuvant Treatment in Breast Cancer

Pérez-Tenorio, Gizeh January 2008 (has links)
(PI3K)/AKT signaling pathway could be a cause of therapeutic resistance in breast cancer. The PI3K/AKT pathway controls cell proliferation, cell growth and survival, and its members include oncogenes and tumor suppressor genes. Alterations in this pathway are frequent in cancer. In this thesis, we aimed to study the biological significance of some of these alterations in a tumor context as well as their clinical value. PIK3CA gene, encoding the PI3K catalytic subunit, was examined for mutations. The tumor suppressor PTEN, that counteracts PI3Kmediated effects, was studied at the protein level whereas amplification of RPS6KB1 (S6K1) and RPS6KB2 (S6K2) genes, encoding two substrates of the mammalian target of rapamycin (mTOR) acting downstream PI3K/AKT, was also inspected. AKT phosphorylation or activation (pAKT) was determined by immunohistochemistry. Other factors related with this pathway, such as HER-2, heregulin (HRG) β1, the cell cycle inhibitor p21WAF1/CIP1, the pro-apoptotic factor Bcl-2, and cyclin D1,  were also considered. These studies were perfomed in two patient materials consisting of premenopausal patients that received endocrine treatment (paper I) and postmenopausal patients randomized to receive radiotherapy (RT) or chemotherapy (CMF) in combination with tamoxifen (Tam) or no endocrine treatment (papers II-IV). In the first material, we found that pAKT indicated higher risk of distant recurrence among endocrine treated patients. In the second material HRGβ1 induced accumulation cytoplasmic p21 in vitro and pAKT was associated with cytoplasmic p21 in the tumors. In addition, p21 cellular location identified subgroups of ER+ patients with different responses to tamoxifen. Other alterations such as PIK3CA mutations and PTEN loss were positively associated in this material. PIK3CA mutations lowered the risk for local recurrences while PTEN loss conferred radiosensitivity as a single variable or combined with mutated PIK3CA. PIK3CA mutations and/or PTEN loss was associated with lower S-phase (SPF). Nevertheless, among patients with low proliferating tumors, these alterations predicted higher risk of recurrence in contrast to those with high proliferating tumors. Finally, we found amplification of the S6K1 and S6K2 genes. S6K2 amplification was associated with cyclin D1 gene amplification, predicted poor recurrence-free survival and breast cancer death, and indicated benefit from tamoxifen. On the other hand, S6K1 amplification was associated with HER-2 amplification/overexpression, indicated higher risk of recurrence and was a predictor of poor response to radiotherapy. These results indicate the potential of this pathway as therapeutic source. / Bröstcancer är en vanlig sjukdom och dödsorsak bland kvinnor i Sverige. Könshormonet östrogen tillsammas med cellernas receptorer för hormonet spelar en viktig roll för bröstcancerutvecklingen. Därför behandlas denna sjukdom med anti-hormonella substanser inriktade mot hämning av östrogensyntes/östrogen receptorn. Tamoxifen är den vanligaste formen av anti-östrogenbehandling som används efter operation. Tamoxifenbehandling förbättrar betydligt 5-årsöverlevnaden hos patienter med östrogenreceptorpositiva tumörer. Emellertid finns det patienter som återkommer med metastaser efter en tid. I det här projektet studerar vi andra receptorer samt deras signalvägar som kan aktivera östrogenreceptorn och därmed orsaka tamoxifenresistens. En sådan receptor är HER-2 vilken överuttrycks i 15-20% vid bröstumörer. HER-2 receptorn kan rekrytera proteiner med enzymatisk aktivitet, till exempel PI3K. PI3K aktiverar ett annat enzym, AKT, vilket är inblandat i en kaskad som leder till tumörtillväxt och tumöröverlevnad (genom till exempel aktivering av östrogenreceptorn). Våra resultat hitills visar att patienter med aktiverat AKT (pAKT) har större risk att få metastaser och därmed sämre överlevnad än patienter utan pAKT, detta trots hormonell behandling. I större material där HER-2 proteinuttrycket korrelerar med pAKT har vi också funnit att patienter med AKTnegativa tumörer kunde dra nytta av både tamoxifen och strålbehandling. Vi har även undersökt PIK3CA genen (som kodar för en del av PI3K) och hittat mutationer i 24% av bröstumörerna. Det är dock ännu oklart hur dessa mutationer ska tas hänsyn till för att kunna bestämma en effektiv behandling. PTEN är ett annat enzym som motverkar PI3K-aktivitet. Bortfall av PTEN förekommer ofta i bröstcancer och  har associerats med PI3K/AKT aktivering. I vårt material var PTEN-förlust frekvent (37%) och associerades med PIK3CA mutationer. PTEN förlust som ensam faktor eller tillsammans med PIK3CA mutationer ökade strålkänslighet. Andra proteiner som är inblandade i PI3K signalvägen är S6K1 och S6K2 och dessa har betydelse för cellens proteinsyntes. Nyligen har vi kunnat visa att generna för både S6K1/2 finns i många kopior (genamplifering) I tumörcellerna hos bröstcancerpatienter. Dessutom fanns det ett positivt samband mellan S6K1/2 amplifiering och amplifiering av andra kända cancergener (som t. ex HER-2 och cyclin D1) men förhållandet till PIK3CA-mutationer var det omvända. Patienter med antigen S6K1 eller HER-2 amplifierade tumörer svarade dåligt på strålbehandling men skulle möjligen kunna behandlas med en specifik substans riktad mot S6K1 eller HER-2. Ett ökat antal kopior av S6K2 indikerade dålig prognos men bra nytta av tamoxifen. Våra resultat visar att PI3K/AKT signalvägen ofta är aktiverad vid bröstcancer och skulle kunna vara en viktig måltavla för behandling.
37

Aggressive B-cell Lymphomas : Studies of Treatment, FDG-PET Evaluation and Prognostic Factors

Adde, Magdalena January 2009 (has links)
To improve outcome in young, high-risk lymphoma patients, treatment was intensified, adding etoposide and rituximab to standard CHOP treatment. Granulocyte-colony stimulating factor (G-CSF) enabled treatment bi-weekly. Results were promising: overall (OS) and event-free survival (EFS) 79% and 60% respectively, median follow up 27 months. Single infusion Ara-C, contrary to expectations, did not prevent relapse in CNS. DLBCL were classified as germinal center (GC) or non-GC derived, using immunohistochemical markers, CD10, BCL6 and MUM1. We investigated the outcome for both phenotypes after adding rituximab to chemotherapy. For 106 patients treated with CHOP alone, the GC phenotype displayed significantly better OS and EFS. In contrast, GC phenotype did not predict outcome in 95 patients treated with immunochemotherapy . Thus, addition of rituximab seems to eliminate the prognostic value of immunohistochemically defined GC phenotypes in DLBCL. To improve evaluation and find non-responders, mid-treatment FDG-PET CT was incorporated into clinical routine for patients with high-risk aggressive lymphoma. For those with positive PET, biopsy followed by treatment intensification was recommended. Twenty-five patients were examined, five with positive PET. Two of these had lymphoma in the biopsy. Two had a negative biopsy, and one had a false positive investigation. Seven patients had increased uptake of uncertain significance. Two patients with uncertain PET, and two with negative PET have relapsed, giving a negative predictive value of 85%. In case of relapse of aggressive lymphoma or if not obtaining CR, high dose chemotherapy with autologous stem cell support (HDT) is standard treatment. HDT outcome for 38 patients with transformed follicular lymphoma was compared to outcome for 79 patients with de novo B-cell lymphoma. At median follow-up of 11.5 years both OS and EFS were superior in the transformed group, OS 67% and 33%, EFS 55% and 27% respectively. Treatment related mortality was less than reported in other studies.
38

Att som förälder få en cancersjukdom : erfarenheter av föräldraansvar

Elmberger, Eva January 2004 (has links)
No description available.
39

Development and validation of a constipation risk assessment scale for use in clinical practice

Richmond, Janice P. January 2002 (has links)
No description available.
40

Biological and histological factors as predictors in rectal cancer patients : A study in a clinical trial of preoperative radiotherapy

Holmqvist, Annica January 2011 (has links)
With improved surgical techniques and preoperative radiotherapy (RT) the local recurrence rate in rectal cancer patients has been reduced, however the mortality rate is still high and there is a huge variation in the response to preoperative RT in patients with the same tumour stage. To improve patient’s survival, it is of great importance to identify good prognostic and predictive factors that help us to select the best suited patients for preoperative RT in the future. For many years, studies of neoplastic transformation have mainly focused on tumour cells. In recent years, researchers have realised that the stroma around tumour cells and their extracellular matrix components also play an important role in tumour carcinogensesis. The aim of this thesis was to investigate the biological factors, survivin and particularly interesting new cysteine-histidine rich protein (PINCH), histological factors, inflammatory infiltration, fibrosis, necrosis, mucinous content, angiogenesis and lymphangiogenesis as well as their relationships to preoperative RT and to clinical variables in rectal cancer patients who participated in a Swedish rectal cancer trial of preoperative RT. In paper I, the expression of survivin and its relationship to preoperative RT and clinical factors were investigated in 98 primary rectal tumours and adjacent normal mucosa. In all patients, positive survivin expression was independently related to worse survival compared to negative survivin expression in a multivariate analysis. In paper II, PINCH expression and its relationship to RT, clinical, histological and biological factors were investigated at the invasive margin and inner tumour area in 137 primary rectal tumours and in cell line of fibroblasts. In patients without RT, strong PINCH expression was independently related to worse survival in a multivariate analysis. No survival relationship was found in the patients with RT, and there was no difference in PINCH expression between the subgroups of non-RT and RT at the invasive margin/inner tumour area. In patients with RT, strong PINCH expression at the inner tumour area was related to a high level of lymphatic vessel density (LVD). In paper III, the frequency of LVD/blood vessel density (BVD) was analysed at the periphery, the inner tumour area and the invasive margin of 138/140 primary rectal tumours and correlated to RT, clinical, histological and biological factors. In all patients, LVD at the periphery of the tumour was independently related to better survival compared to LVD at the inner tumour area/invasive margin. In all patients, a higher LVD at the periphery was related to negative (wild type) p53 expression. In paper IV, the inflammatory infiltration, fibrosis, necrosis and mucinous content were studied in relation to RT, clinical and biological parameters in preoperative biopsies (n = 153) and in primary tumours (n = 148). In all patients and in the subgroups of non-RT and RT a higher grade of inflammatory infiltration was independently related to improved survival compared to weak inflammatory infiltration in a multivariate analysis. In this thesis, survivin, PINCH, LVD and inflammatory infiltration are independent prognostic factors in rectal cancer patients who participated in a clinical trial of preoperative RT. This information may help us to improve patient’s survival by selecting the best suited patients for preoperative RT in the future.

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