| 1. |
- Andersson, Charlotta, 1976-
(författare)
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Significance of Wilms’ tumor gene 1 as a biomarker in acute leukemia and solid tumors
- 2016
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Wilms’ tumor gene 1 (WT1) is a zinc finger transcriptional regulator with crucial functions in embryonic development. Originally WT1 was described as a tumor suppressor gene, but later studies have shown oncogenic properties of WT1 in a variety of tumors. Because of its dual functions in tumorigenesis, WT1 has been described as a chameleon gene. In this thesis, the significance of WT1 as a biomarker was investigated in acute myeloid leukemia (AML), clear cell renal cell carcinoma (ccRCC), ovarian carcinoma (OC) and childhood B-cell precursor acute lymphoblastic leukemia (BCP-ALL).Previous studies have suggested that expression of WT1 is a potential marker for detection of minimal residual disease (MRD) in AML. We aimed to define expression of WT1 as an MRD marker in AML. In adult AML patients, we found that a reduction of WT1 expression in bone marrow (≥ 1-log) detected less than 1 month after diagnosis was associated with an improved overall survival (OS) and freedom from relapse (FFR). In peripheral blood, a reduction of WT1 expression (≥ 2-log) detected between 1 and 6 months after treatment initiation was associated with an improved OS and FFR.WT1 harbor pathogenic genetic variants in a considerable proportion of AML and T-lymphoblastic leukemia (T-ALL), but mutations have not been reported in BCP-ALL. We aimed to evaluate the clinical impact of WT1 mutations and single nucleotide polymorphisms (SNPs) in BCP-ALL. Pathogenic mutations in the WT1 gene were rarely seen in childhood BCP-ALL. However, five WT1 SNPs were identified. In survival analyses, WT1 SNP rs1799925 was found to be associated with worse OS, indicating that WT1 SNP rs1799925 may be a useful marker for clinical outcome in childhood BCP-ALL. We also explored whether WT1 mutations and SNPs in ccRCC could be used as biomarkers for risk and treatment stratification. We therefore examined whether SNPs or mutations in WT1 were associated with WT1 expression and clinical outcome. Sequencing analysis revealed that none of the previously reported WT1 mutations were found in ccRCC; however, we identified six different WT1 SNPs. Our data suggest that pathogenic WT1 mutations are not involved in ccRCC, and the prognostic significance of WT1 SNPs in ccRCC is considerably weak. However, a favorable OS and disease-specific survival were found in the few cases harboring the homozygous minor allele.OC has a poor prognosis, and early effective screening markers are lacking. Serous OCs are known to express the WT1 protein. Overexpressed oncogenic proteins can be considered potential candidate antigens for cancer vaccines and T-cell therapy. It was therefore of great interest to investigate whether anti-WT1 IgG antibody (Ab) measurements in plasma could serve as biomarkers of anti-OC response. We found limited prognostic impact, but the results indicated that anti-WT1 IgG Ab measurements in plasma and WT1 staining in tissue specimens could be potential biomarkers for patient outcome in the high-risk subtypes of OCs.In conclusion, the results of this thesis indicate that WT1 gene expression can provide information about MRD of patients with AML, and WT1 SNP rs1799925 may be used as a biomarker for predicting clinical outcome in childhood BCP-ALL. In ccRCC, the prognostic significance of WT1 SNPs is weak and limited to the subgroup of patients that are homozygous for the minor allele. In OCs anti-WT1 IgG Ab measurement in plasma and WT1 staining in tissue specimens could possibly be used as biomarkers for predicting patient outcome in the high-risk subtypes of OCs.
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| 2. |
- Berglund, Leo, 1986-
(författare)
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Kritiskt tänkande som utbildningsmål : Från modernistisk filosofi till policy för högre utbildning
- 2021
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The goal of critical thinking in higher education is paradoxical, since it implies a form of education that both directs the student towards a pre-defined goal, and commands the student to be autonomous. This paradox is studied in four contexts, as to investigate what pedagogical contradictions the goal of critical thinking generates, and how they transform pedagogical thinking. 1) In the 1930s, European logical positivists cooperated with American pragmatists to "unify science". For Dewey, the realisation of this ideal depended on individuals adopting a "scientific attitude", which could be cultivated in schools and universities. Dewey’s position influenced a pedagogical discourse of critical thinking as the spirit of rational and democratic citizenship. 2) In the 1980s, the Critical Thinking Movement (CTM) addressed the issue on how to make logical thinking applicable in everyday life. Understanding critical thinking as individuals’ problem-solving skills, the CTM essentially inverted the collectivist political orientation of Dewey and the neo-positivists. 3) In the Swedish 1968 governmental investigation of higher education (U 68), a sociologically informed conception of critical thinking, that involved the student in the project of social planning, was promoted. However, educational experts perceived critical thinking as a vague goal, which could not be operationalised. In the 1990s, critical thinking reappeared as part of the doctrine of learning, but only as a generic term used to signify advanced cognitive operations in relation to different subject matters. 4) In contemporary courses in critical thinking held at Swedish universities, radically diverse conceptions are being taught. An analysis of three courses identified three subjectivities "called" by the arrangements and bodies of literature in the courses: the critical thinker as reason, intellect, and moral consciousness. Each of the subjectivities, however, comprises inconsistencies and contradictions, since they are all to be both produced by and autonomous from the orders that the educational institution represents. The dissertation is concluded by a discussion on critical thinking as both a goal and a by-product of education.
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| 3. |
- Bråndal, Anna, 1966-
(författare)
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Rehabilitation after stroke with focus on early supported discharge and post-stroke fatigue
- 2016
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Background Stroke is a major cause of disability worldwide. After treatment in a specialized stroke unit, early supported discharge (ESD) followed by home rehabilitation has shown to be an effective way to improve patient outcome and quality of care for persons with mild to moderate stroke. ESD service is recommended in the national and international guidelines for stroke care, but has only partially been implemented in Sweden. Following stroke, fatigue is a common consequence that often becomes more evident when the patient comes home. Currently, there is insufficient evidence about how to measure, treat and handle post-stroke fatigue. The overall aim of this thesis was to evaluate and implement early supported discharge (ESD) based on stroke patients experience after discharge from the stroke unit and local conditions. The aim was also to evaluate post-stroke fatigue with a potentially valid and reliable scale and finally to prepare for a study to evaluate cardiorespiratory training as a part of ESD service for patients with post-stroke fatigue.Methods In paper I, nine strategically chosen patients were interviewed of their experience of falling ill, the hospital stay, discharge, contact with health care after discharge and their request of support. Papers II-III describe and evaluate the development, content, implementation and effects of a locally adopted method for early supported discharge (Umeå Stroke Center ESD) in modern stroke care. Paper II included 153 consecutive patients and paper III, 30 232 patients with first-ever stroke registered in the Riksstroke registry in Sweden. Paper II evaluated number of patients/year, clinical and functional health status, satisfaction in relation to needs, accidental falls/other injuries and resources with the result summarized in a value compass. The implementation process was evaluated retrospectively by means of Consolidated Framework for Implementation (CFIR). Paper III evaluated patient reported outcome measurements (PROMs) at 3 months. The primary outcome in paper III was satisfaction with the rehabilitation after discharge. Secondary outcomes were information about stroke provided, tiredness/fatigue, pain, dysthymia/depression, general health status and dependence in activities of daily living (mobility, toilet hygiene and dressing). Multivariable logistic regression models for each PROM was used to analyze associations between PROMs and ESD/no ESD. In Paper IV, the Fatigue Assessment scale (FAS) was translated into Swedish and evaluated regarding psychometric properties when self-administered by persons with mild to moderate stroke. 72 consecutively patients selected from the stroke unit admission register received a letter including three questionnaires: the FAS, the Short Form Health Survey (SF-36) subscale for vitality and the Geriatric Depression Scale GDS-15. A second letter with FAS was sent within 2 weeks, for re-test evaluation. Paper V is a study protocol for a planned randomized controlled trial (RCT) of 50 consecutive stroke patients will who receive stroke unit care followed by ESD-service at Umeå Stroke Center, University Hospital, Umeå, Sweden. Paper V will investigate if a structured cardiorespiratory interval training program (CITP) added to the ESD-service may result in relieved post-stroke fatigue and increased oxygen uptake.Results The interviews in Paper I revealed three main categories with subcategories: “Responsible and implicated”, “Depersonalized object for caring measures” and “The striving for repersonalization and autonomy”. The findings indicate that coming home gave the informants’ important insights and understanding of the stroke, its consequences and was also an important factor for the recovery. Paper II-III showed that it is possible to develop and implement an adapted ESD service for stroke patients based on the patients’ experiences and requests, evidence-based recommendations and local conditions. The ESD service reduced dependence of activity, increased mobility with seemingly no increased risk of accidental falls or other injuries. The patient satisfaction in relation to needs regarding the ESD was high. Paper III showed that patients that received ESD were more satisfied with rehabilitation after discharge, had less need for assistance with ADL and less dysthymia/depression compared to patients that did not receive ESD. Study IV showed that the Swedish FAS used at home as a selfadministered questionnaire is a reliable and valid questionnaire for measuring fatigue in persons with mild to moderate stroke. The internal consistency was good, the agreement between the test and retest reliability for individual items (weighted kappa) was for the majority of items good or moderate. The relative reliability for total scores was good and the absolute reliability was 9 points. The Swedish FAS had no floor nor ceiling effects and correlated both with the SF-36, subscale for vitality and the GDS-15 indicating convergent construct validity, but not divergent construct validity.Conclusion It is possible to develop and implement ESD care for stroke patients based on patients’ experience and needs, evidence-based principles and local conditions. Early supported discharge (ESD) in the setting of modern stroke unit care appears to have positive effects on rehabilitation in the subacute phase. The Swedish FAS used at home as a self-administered questionnaire is reliable and valid for measuring fatigue in persons with mild to moderate stroke.
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| 4. |
- Forsslund, Jonas, 1983-
(författare)
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Preparing Spatial Haptics for Interaction Design
- 2016
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Spatial haptics is a fascinating technology with which users can explore and modify3D computer graphics objects with the sense of touch, but its application potentialis often misunderstood. For a large group of application designers it is still unknown,and those who are aware of it often have either too high expectations of what is technicallyachievable or believe it is too complicated to consider at all. In addition, spatialhaptics is in its current form ill-suited to interaction design. This is partly because theproperties and use qualities cannot be experienced in an application prototype until asystem is fully implemented, which takes too much effort to be practical in most designsettings. In order to find a good match between a solution and a framing of aproblem, the designer needs to be able to mould/shape/form the technology into a solution,but also to re-frame the problem and question initial conceptual designs as shelearns more about what the technology affords. Both of these activities require a goodunderstanding of the design opportunities of this technology.In this thesis I present a new way of working with spatial haptic interaction design.Studying the serially linked mechanism from a well-known haptic device, and a forcereflectingcarving algorithm in particular, I show how to turn these technologies froman esoteric engineering form into a form ready for interaction design. The work isgrounded in a real application: an oral surgery simulator named Kobra that has beendeveloped over the course of seven years within our research group. Its design hasgone through an evolutionary process with iterative design and hundreds of encounterswith the audience; surgeon-teachers as users and potential customers. Some ideas, e.g.gestalting authentic patient cases, have as a result received increased attention by thedesign team, while other ideas, e.g. automatic assessment, have faded away.Simulation is an idea that leads to ideals of realism; that e.g. simulated instrumentsshould behave as in reality, e.g. a simulated dental instrument for prying teeth is expectedto behave according to the laws of physics and give force and torque feedback.If it does not, it is a bad simulation. In the present work it is shown how some of therealism ideal is unnecessary for creating meaningful learning applications and can actuallyeven be counter-productive, since it may limit the exploration of creative designsolutions. This result is a shift in perspective from working towards constantly improvingtechnological components, to finding and making use of the qualities of modern,but not necessarily absolute cutting-edge, haptic technology.To be able to work creatively with a haptic system as a design resource we needto learn its material qualities and how - through changing essential properties - meaningfulexperiential qualities can be modulated and tuned. This requires novel tools andworkflows that enable designers to explore the creative design space, create interactionsketches and tune the design to cater for the user experience. In essence, this thesisshows how one instance of spatial haptics can be turned from an esoteric technologyinto a design material, and how that can be used, and formed, with novel tools throughthe interaction design of a purposeful product in the domain of dental education.
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| 5. |
- Idahl, Annika, 1965-
(författare)
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Chlamydia trachomatis as a risk factor for infertility in women and men, and ovarian tumor development
- 2009
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Background: Chlamydia trachomatis in women is a risk factor for tubal factor infertility and extra uterine pregnancies, but the impact of a C. trachomatis infection on male fertility is unclear. It is also hypothesized that persistent infection with C. trachomatis, or other microorganisms, might initiate/promote ovarian tumor development. The aims of the thesis were to study whether C. trachomatis serum antibodies in women and men had an impact on infertility diagnoses, semen characteristics, pregnancy rates and pregnancy outcomes; furthermore, to explore associations of C. trachomatis, and Mycoplasma genitalium, plasma antibodies with epithelial ovarian cancer and borderline ovarian tumors, as well as the presence of C. trachomatis bacteria, and other microorganisms, in ovarian tissues. Materials and methods: Papers I and II: 244/226 infertile couples were tested for serum C. trachomatis IgG, IgA, IgM and chlamydial Heat Shock Protein 60 (cHSP60) IgG antibodies. C. trachomatis IgG positive couples were also tested for C. trachomatis DNA in a urine sample. The follow-up period was 14-54 months. 244 spontaneously pregnant women were also tested for serum C. trachomatis IgG antibodies. Papers III and IV: Plasma samples from 291 women with epithelial ovarian cancer, borderline ovarian tumors and benign conditions, and plasma samples from 271 healthy controls, were analyzed for C. trachomatis IgG, IgA and cHSP60-1 IgG and M. genitalium IgG antibodies. Ovarian tissues from 186 women with benign ovaries, borderline ovarian tumors and epithelial ovarian cancer, as well as tissues from the contra lateral ovary in 126 women, were analyzed for the presence of C. trachomatis, M. genitalium, Neisseria gonorrhoeae, HPV and the polyoma viruses BKV and JCV with nucleic acid amplification tests. Results: Papers I and II: The prevalence of C. trachomatis IgG antibodies was higher among infertile than fertile women, and there were 9 couples with ongoing C. trachomatis infections. In men, C. trachomatis IgG and IgA antibodies were associated with a reduced likelihood to achieve pregnancy for the couple, as well as lower sperm concentration, reduced sperm motility and vitality, increased teratozoospermia index and the occurrence of leukocytes. C. trachomatis IgG and cHSP60 IgG antibodies in infertile women were associated with tubal factor infertility, but not with reduced pregnancy rates or outcomes. Paper III: cHSP60-1 IgG antibodies were associated with ovarian cancer belonging to the postulated type II pathogenetic pathway when plasma samples obtained more than one year prior to diagnosis were analyzed. M. genitalium IgG antibodies were associated with borderline ovarian tumors; however a statistical type 1 error cannot be excluded. Paper IV: None of the microorganisms studied were found in the ovarian tissue samples. Conclusions: C. trachomatis IgG and IgA antibodies in the man substantially decreases the chances of the infertile couple to achieve pregnancy, and are associated with subtle negative changes in semen characteristics. C. trachomatis IgG and cHSP60 IgG antibodies in the woman are risk factors for tubal factor infertility. Prospective plasma cHSP60-1 IgG antibodies are associated with type II ovarian carcinomas, but C. trachomatis bacteria, or the other microorganisms studied, could not be detected in benign, borderline or malignant ovarian tissues.
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| 6. |
- Israelsson, Pernilla, 1984-
(författare)
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Mechanisms for immune escape in epithelial ovarian cancer
- 2021
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Tumors develop mechanisms to subvert the immune system, constituting immune escape. Epithelial ovarian cancer (EOC), the deadliest of all gynecological malignancies, uses a variety of mechanisms to undermine immune surveillance, aiding its establishment and metastatic spreading. Despite progress in oncoimmunology, a lot remains unknown about the cancer-immune system interplay. The aim of this thesis was to study tumor-mediated mechanisms for immune escape in EOC patients, focusing on the role of cytokines and EOC- derived exosomes. Cytokines are key molecules regulating immune effector functions in health and disease. We used real-time RT-qPCR and a set of primers and probes for 12 cytokines, discriminating between different immune responses and compared the cytokine mRNA expression profiles locally in the TME and systemically in peripheral blood immune cells of EOC patients, to women with benign ovarian conditions and women with normal ovaries. The cytokine mRNA expression was in general most prominent in EOC patients, confirming the immunogenicity of EOC. We found significant dominance of inflammatory and immunosuppressive/ regulatory cytokines, known to promote tumor progression by priming and activating T regulatory cell-mediated immune suppression. In contrast, IFN-γ, crucially important for evoking a cytotoxic anti-tumor response, was not upregulated. Instead, a systemic increase of IL-4 prevailed, deviating the immune defense towards humoral immunity. With regard to our cytokine study, we performed comparative analyses of cytokine mRNA versus protein expression in the EOC cell lines OVCAR-3 and SKOV-3. We found that cytokine mRNA signals were universally detected, and in some instances translated into proteins, but the protein expression levels depended on the material analyzed and the method used. Due to the high sensitivity of real-time RT-qPCR, we suggest that cytokine mRNA expression profiles can be used for some instances, such as in studies of mechanistic pathways and in comparisons between patient groups, but cannot replace expression at the protein level. Exosomes are nanometer-sized vesicles of endosomal origin, released by virtually all cells, participating in normal and pathological processes. Like many tumors, EOC is a great exosome producer. We isolated exosomes from EOC ascitic fluid and supernatant from tumor explant cultures to study their effect on the NK cell receptors NKG2D and DNAM-1, involved in tumor killing. We found that EOC exosomes constitutively expressed NKG2D ligands on their surface while DNAM-1 ligand expression was rare and not associated with the exosomal membrane. Consistently, the major cytotoxic pathway of NKG2D-mediated killing was dysregulated by EOC exosomes while the accessory DNAM-1- mediated pathway remained unchanged. Our results provide a mechanistic explanation to the previously made observation that in EOC patients, tumor killing is only dependent on the accessory DNAM-1 pathway. Following these iii iv results, we studied NKG2D-mediated cytotoxicity in vivo in EOC patients before and after surgery. We found that the serum exosomes isolated from EOC patients were able to downregulate the NKG2D receptor and suppress NKG2D-mediated cytotoxicity in NK cells from healthy donors, in a similar way as exosomes from EOC ascites. We also found that surgery of the primary EOC tumor has a beneficial effect on the patients’ anti-tumor cytotoxic immune response. One mechanistic explanation could be a decrease in circulating NKG2D ligand- expressing exosomes, thus improving the cytotoxic NK cell function. In conclusion, our results contribute to the understanding of the mechanisms responsible for tumor immune escape in general, and in EOC patients in particular, and might be useful in developing novel antitumor therapies. Our studies highlight the prevailing immunosuppression in the local TME and the immunosuppressive role of EOC exosomes. Furthermore, they support the notion that cancer surgery is also a way of removing exosome-producing cells and reducing the serum concentration of immunosuppressive exosomes, thus boosting the patients’ cytotoxic anti-tumor response.
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| 7. |
- Jonsson, Sarah, 1982-
(författare)
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Pelvic inflammatory disease and epithelial ovarian tumors
- 2023
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Background: Epithelial ovarian cancer and borderline ovarian tumors consist of several histotypes in which high-grade serous carcinoma is the most common. The majority of epithelial ovarian tumors are considered to originate in the fimbriated end of the fallopian tubes. What initiates these tumors is far from completely understood. Pelvic inflammatory disease has been proposed as a modifiable risk factor for epithelial ovarian tumors. A major cause of pelvic inflammatory disease is Chlamydia trachomatis which has been shown to have cancer-causing potential. The overall purpose of this thesis was to study associations of pelvic inflammatory disease and C. trachomatis with risk of epithelial ovarian tumors.Methods: In a cross-sectional study (Paper I) we collected ovarian tissue and corresponding blood samples from 69 women undergoing surgery due to suspected ovarian pathology. C. trachomatis specific protein (immunohistochemistry) and C. trachomatis DNA (qPCR) in ovarian tissue were analyzed (Paper I). In a nested case-control study (Paper II) prospective blood samples from 92 women diagnosed with high-grade serous ovarian cancer were matched to four controls each for age and date of plasma sampling. C. trachomatis specific plasma antibodies were analyzed by commercial Enzyme-Linked ImmunoSorbent Assay (ELISA) and Micro-ImmunoFluorescence (MIF) (Paper I and Paper II). We performed a nationwide register-based case-control study where we included 15 072 women diagnosed with epithelial ovarian cancer (Paper III), 4782 women diagnosed with borderline ovarian tumors (Paper IV), and ten controls each matched for age and residential district. Using national Swedish registers, we retrieved data on historyof pelvic inflammatory disease and the potential confounding factors parity, educational level, previous gynecological surgery, and hormonal therapy.Results: We found C. trachomatis DNA in ovarian tissue of eight women with ovarian carcinoma, but not in ovarian tissue from women with borderline ovarian tumors or benign disease (Paper I). The prevalence of the C. trachomatis specific protein did not differ in benign and malignant tissue (Paper I). Prevalence of C. trachomatis specific plasma antibodies was similar in cases and controls at diagnosis (Paper I) and prospectively (Paper II). A history of clinically verified pelvic inflammatory disease was associated with an increased risk of epithelial ovarian cancer overall (Paper III) and borderline ovarian tumors overall (Paper IV). Histotype-specific analyses showed an increased risk of serous carcinoma (Paper III), high-grade serous carcinoma (Paper III), clear cell carcinoma (Paper III), and serous borderline ovarian tumors (Paper IV) but not significantly with other histotypes. A dose-response relationship was seen between an increased number of pelvic inflammatory disease episodes and epithelial ovarian cancer (Paper III), as well as borderline ovarian tumors (Paper IV).Conclusions: This thesis contributes to an improved understanding of the association between pelvic inflammatory disease and epithelial ovarian tumors. The results regarding C. trachomatis are inconclusive and suggests that the association of pelvic inflammatory disease with epithelial ovarian tumors acts through mechanisms other than Chlamydia alone.
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| 8. |
- Li, Xingru, 1987-
(författare)
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Wilms' tumor gene 1 in different types of cancer
- 2015
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The Wilms’ tumor gene 1 (WT1) was first reported as a tumor suppressor gene in Wilms’ tumor. However, later studies have shown the oncogenic properties of WT1 in a variety of tumors. It was recently proposed that WT1 was a chameleon gene, due to its dual functions in tumorigenesis. We aimed to investigate the clinical significance of WT1 as biomarker in acute myeloid leukemia (AML) and clear cell renal cell carcinoma (ccRCC) and to elucidate the function of WT1 as an oncogene in squamous cell carcinoma of head and neck (SCCHN).In AML, it was suggested that WT1 expression was an applicable marker of minimal residual disease (MRD). In adult patients with AML, we found a good correlation between WT1 expression levels normalized to two control genes, β-actin and ABL. Outcome could be predicted by a reduction in WT1 expression in bone marrow (≥ 1-log) detected less than 1 month after diagnosis, when β-actin was used as control. Also, irrespective of the control gene used, outcome could be predicted by a reduction in WT1 expression in peripheral blood (≥ 2-log) detected between 1 and 6 months after treatment initiation.Previous studies in RCC demonstrated that WT1 acted as a tumor suppressor. Thus, we tested whether single nucleotide polymorphisms (SNPs) or mutations in WT1 might be associated with WT1 expression and clinical outcome in patients with ccRCC. We performed sequencing analysis on 10 exons of the WT1 gene in a total of 182 patient samples, and we identified six different SNPs in the WT1 gene. We found that at least one or two copies of the minor allele were present in 61% of ccRCC tumor samples. However, no correlation was observed between WT1 SNP genotypes and RNA expression levels. Moreover, none of the previously reported WT1 mutations were found in ccRCC. Nevertheless, we found that a favorable outcome was associated the homozygous minor allele for WT1 SNP. We then further investigated whether WT1 methylation was related to WT1 expression and its clinical significance. Methylation array and pyrosequencing analyses showed that the WT1 promoter region CpG site, cg22975913, was the most frequently hypermethylated CpG site. We found a trend that showed nearly significant correlation between WT1 mRNA levels and hypermethylation in the 5’-untranslated region. Hypermethylation in the WT1 CpG site, cg22975913, was found to be associated with patient age and a worse prognosis.One previous study reported that WT1 was overexpressed in SCCHN. That finding suggested that WT1 might play a role in oncogenesis. We found that both WT1 and p63 could promote cell proliferation. A positive correlation between WT1 and p63 expression was observed, and we identified p63 as a WT1 target gene. Furthermore, several known WT1 and p63 target genes were affected by knocking down WT1. Also, co-immunoprecipitation analyses demonstrated a protein interaction between WT1 and p53.In summary, WT1 gene expression can provide useful information for MRD detection during treatment of patients with AML. In RCC, our results suggested that the prognostic impact of WT1 SNPs was limited to the subgroup of patients that were homozygous for the minor allele, and that WT1 promoter hypermethylation could be used as a prognostic biomarker. In SCCHN, WT1 and p63 acted as oncogenes by affecting multiple genes involved in cancer cell growth.
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| 9. |
- Lukanova, Annekatrin, 1966-
(författare)
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Endogenous hormones in the etiology of ovarian and endometrial cancers
- 2004
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The main purpose of this thesis was to examine the relationship of pre-diagnostic circulating levels of sex-steroids (androgens and estrogens), sex hormone binding globuline (SHBG), insulin-like growth factor-I (IGF-I), IGF binding proteins (BP) and C-peptide (as a marker of pancreatic insulin secretion) with risk of ovarian and endometrial cancer. Additionally, the interrelationships of body mass index (BMI), sex-steroids, IGF-I and IGFBP-3 were examined. Two case-control studies were nested within 3 prospective cohort studies centered in New York (USA), Umeå (Sweden) and Milan (Italy). The ovarian study included 132 cancer cases. The endometrial study included 166 cancer cases in the IGF-I and C-peptide component and 124 postmenopausal cases in the sex-steroids component. For each case, two controls matching the case for cohort, age, menopausal status and date at recruitment were selected. In total 286 and 315 controls were included in the ovarian and endometrial cancer studies, respectively. Odds ratios (OR) and their 95% confidence intervals (CI) for cancer risk associated with increasing hormone concentrations were estimated by conditional logistic regression. The cross-sectional analysis was based on anthropometric and hormonal data from 620 controls selected for the two nested case-control studies. There was no association of prediagnostic androstenedione, testosterone, DHEAS, SHBG or estrone with ovarian cancer risk in the whole study population or in women who were pre- or postmenopausal at blood donation. In the premenopausal group, risk appeared to increase with increasing androstenedione (OR (95% CI) for the highest tertile: 2.35 (0.81-6.82), p=0.12). There was no association of IGF-I, IGFBP-1, 2, 3 or C-peptide concentrations with risk of ovarian cancer risk in the study group as a whole. In analyses restricted to subjects who had developed ovarian cancer at an early age (<55), circulating IGF-I was directly and strongly associated with risk (OR (95% CI): 4.74 (1.20-18.7), p<0.05 for the highest IGF-I tertile). In the endometrial study, previous observations were confimed that elevated circulating estrogens and androgens and decreased SHBG increase risk of developing endometrial malignancy after menopause. Multivariate ORs (95% CI) for endometrial cancer for quartiles with the highest hormone levels were: 4.13 (1.76-9.72), p<0.001 for estradiol; 3.67 (1.71-7.88), p=0.001 for estrone; 2.15 (1.05-4.40), p<0.04 for androstenedione; 1.74 (0.88-3.46), p=0.06 for testosterone; 2.90 (1.42-5.90), p<0.01 for DHEAS and 0.46 (0.20-1.05), p<0.01 for SHBG. Prediagnostic IGF-I, IGFBP-1, -2 and –3 were not related to risk of endometrial cancer in the whole study population. In postmenopausal women, levels of IGFBP-1 were inversely related to risk with an OR for the highest quartile of 0.36 (0.13-0.95), p<0.05. Endometrial cancer risk increased with increasing levels of C-peptide (p<0.01), up to an OR of 4.40 (1.65-11.7) for the highest quintile after adjustment for BMI and other confounders. The cross-sectional analyses showed that in both pre- and postmenopausal women SHBG decreased with increasing BMI. In the postmenopausal group, estrogens, testosterone and androstenedione increased with BMI, while the association with IGF-I was non-linear, the highest mean IGF-I concentration being observed in women with BMI between 24 and 25. In postmenopausal women, IGF-I was positively related to androgens, inversely correlated with SHBG, and was not correlated with estrogens. In conclusion, elevated pre-diagnostic sex-steroids, IGF-I or C-peptide increase risk of developing ovarian and endometrial cancer. BMI influences the circulating levels of these hormones, especially after menopause.
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| 10. |
- Lundin, Maria, 1978-
(författare)
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Adsorption of biopolymers and their layer-by-layer assemblies on hydrophilic surfaces
- 2009
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- It is widely known that surfaces play an important role in numerous biological processes and technological applications. Thus, being able to modify surface properties provides an opportunity to control many phenomena occurring at interfaces. One way of controlling surface properties is to adsorb a polymer film onto the surface, for example through layer-by-layer (LbL) deposition of polyelectrolytes. This simple but versatile technique enables various polymers, proteins, colloidal particles etc. to be incorporated into the film, resulting in a multifunctional coating. Due to recent legislations and a consumer demand for more environmentally friendly products, we have chosen to use natural polymers (biopolymers) from renewable resources. The focus of this thesis has been on the adsorption of biopolymers and their layer-by-layer formation at solid-liquid interfaces; these processes have been studied by a wide range of techniques. The main method was the quartz crystal microbalance with dissipation monitoring (QCM-D), which measures the adsorbed mass, including trapped solvent and the viscoelastic properties of an adsorbed film. This technique was often complemented with an optical method, such as ellipsometry or dual polarization interferometry (DPI), which provided information about the “dry” polymer or protein adsorbed mass. From this combination, the solvent content and density of the layers was evaluated. In addition, the surface force apparatus (SFA), X-ray photoelectron spectroscopy (XPS), total internal reflection fluorescence (TIRF), and fluorescence resonance energy transfer (FRET) were utilized, providing further information about the film structure, chemical composition, and polymer inter-layer diffusion. Adsorption studies of the glycoprotein mucin, which has a key role in the mucousal function, showed that despite the net negative charge of mucin, it adsorbed on negatively charged substrates. The adsorbed layer was highly hydrated and the segment density on the substrate was low. We showed the importance of characterizing the mucin used, since differences in purity, such as the presence of albumin, gave rise to different adsorption behaviours in terms of both adsorbed amount and structure. The adsorbed mucin layer was to a large extent desorbed upon exposure to the anionic surfactant sodium dodecyl sulfate (SDS). In order to prevent desorption, we demonstrated that a protective layer of the cationic polysaccharide chitosan could be adsorbed onto the mucin layer and that the mucin-chitosan complexes resisted the desorption normally induced by association with SDS. Moreover, the association between chitosan and SDS was examined at the solid-liquid interface, in the bulk, and at the air-water interface. In all these environments chitosan-SDS complexes were formed and a net charge reversal of the complexes from positive to negative was observed when the concentration of SDS was increased. Furthermore, the LbL deposition method could be used to form a multilayer-like film by alternate adsorption of mucin and chitosan on silica substrates. The LbL technique was also applied to two proteins, lysozyme and β-casein with the aim of building a multilayer film consisting entirely of proteins. These proteins formed complexes at the solid-liquid interface, resulting in a proteinaceous layer, but the build-up was highly irregular with an increase in adsorbed amount per protein deposition cycle that was far less than a monolayer.Continuing with chitosan, known to have antibacterial properties we assembled multilayers with an anti-adhesive biopolymer, heparin, to evaluate the potential of this system as a coating for medical implants. Multilayers were assembled under various solution deposition conditions and the film structure and dynamics were studied in detail. The chitosan-heparin film was highly hydrated, in the range 60-80 wt-% depending on the deposition conditions. The adsorbed amount and thickness of the film increased exponential-like with the number of deposition steps, which was explained by inter-diffusion of chitosan molecules in the film during the build-up. In a novel approach, we used the distant dependent FRET technique to prove the inter-layer diffusion of fluorescent-labelled chitosan molecules within the film. The diffusion coefficient was insignificantly dependent on the deposition pH and ionic strength, and hence on the film structure. With the use of a pH sensitive dye buried under seven chitosan-heparin bilayers, we showed that the dye remained highly sensitive to the charge of the outermost layer. From complementary QCM-D data, we suggested that an increase in the energy dissipation does not necessarily indicate that the layer structure becomes less rigid.
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