| 1. |
- Andersson, Håkan, 1944
(författare)
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Radioimmunotherapy of experimental ovarian cancer with Astatine-211. An in vivo model for consolidation treatment in women
- 2000
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- About 850 new cases of ovarian cancer are diagnosed in Sweden every year. In 75 % of the patients the tumour has spread outside the ovaries. The standard treatment is surgery followed by six courses of combination chemotherapy. In spite of a very high frequency of clinical complete responses the 5-year survival is not satisfactory. Thus there is a great need for consolidating therapy.Radioimmunotherapy (RIT), i.e. treatment with specific monoclonal antibodies (MAb) labelled with radionuclides has been tried for various tumours experimentally and clinically. In most studies b-emitters have been used but for micrometastases an a-emitter with a very short tissue range may be better.The purpose of this study was to examine the in vitro effect of the a-emitter Astatine-211 (211At) and to investigate the therapeutic efficacy of regional administration of the specific antibody MOv18 labelled with 211At to nude mice with intraperitoneal growth of human ovarian cancer. Methods. For the in vitro studies the two human cancer cell lines NIH:OVCAR-3 and Colo-205 were used. Cell suspensions were treated with free 211At, 211At-albumin, 211At-Mab or with photon irradiation. The human ovarian cancer cell line NIH:OVCAR-3 was used for the in vivo studies. Two weeks after the inoculation of cells, when the tumour still was microscopic, 211At-MOv18 was injected intraperitoneally. The therapeutic effect was evaluated six weeks later except in the long-term studyResults. In vitro the uptake of free 211At on both cell lines was unexpectedly high. A low number (19-31) of 211At decays on the cell surface was needed for 37% cell survival for both cell types.In the short term in vivo studies 18 of 20 mice were tumour-free when 211At-MOv18 was injected i.p. In the long-term study the survival was significantly better for treated than for untreated mice. Thirty-three per cent of the animals were tumour-free at the end of the study.Conclusion. Intraperitoneal radioimmunotherapy with an 211At-labelled specific antibody is an effective treatment of human ovarian cancer growing in nude mice. Hopefully, this treatment will be of value as consolidating treatment in women with minimal residual disease after surgery and chemotherapy
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| 2. |
- Ahlgren, Johan, 1960-
(författare)
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Studies on Prediction of Axillary Lymph Node Status in Invasive Breast Cancer
- 2002
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Breast cancer is the most common malignancy among females in Sweden. Axillary lymph-node dissection is a standard procedure in the management of breast cancer, aiming at obtaining prognostic information for adjuvant therapy decisions. Axillary dissection entails considerable morbidity. The aims of this study were to establish more selective surgical approaches and to investigate angiogenesis, a potential predictor for lymph-node metastases and prognosis.Clinical nodal status, tumour size and S-phase were associated with nodal metastases in cohort of 1145 women. The proportion of nodal metastases was 13% in the subgroup with the lowest risk.In a study from two registries, 675 and 1035 breast cancers ≤10 mm diagnosed by screening mammography had nodal metastases in 6,5% and 7%, respectively. Clinically detected cancers had a risk of 16% and 14%, respectively.In a study on 415 women, a 5-node biopsy of the axilla had a sensitivity of 97,3% and a false negative rate of 2,7% in comparison with axillary dissection.Six sections from 21 breast cancers were analysed for microvessel density (MVD). The inter-section variation contributed more to the total variance than inter-tumour variation, 45,0% and 37,3%, respectively.In a cohort of 315 women, breast cancers with high MVD more frequently had p53 mutations (27,1%) compared with cases with low MVD (18,4%). This difference was not statistically significant (p=0,075). p53 mutations were associated with a worse outcome, whereas MVD was not.In conclusion, women with screening detected ≤10 mm breast cancers have a low risk of lymph node metastases and some may not need axillary dissection in the future. The 5-node biopsy could be an alternative to axillary dissection. MVD is associated with methodological weaknesses and routine use is not recommended.
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| 3. |
- Alvarado-Kristensson, Maria
(författare)
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Regulation of neutrophil apoptosis
- 2004
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The human neutrophil is the most abundant granulocyte and the major type of cell involved in an acute inflammatory response. Neutrophils are armed with various systems of enzymes, that can find and kill pathogens, but unfortunately, these "weapons" cannot distinguish between the host tissues and the "invaders." Therefore, an extensive neutrophil reaction leads to continuous release of toxic metabolites, which causes successive self-destruction of host tissues and possibly also organ failure. Such a series of destructive events has been implicated in diseases such as rheumatoid arthritis, myocardial infarction/reperfusion injury, atherogenesis, asthma, cystic fibrosis, emphysema, and vasculitis. Resolution of an acute inflammatory process depends on termination of neutrophil emigration from blood vessels and clearance of extravasated neutrophils and their metabolic products. Outside the blood vessels, neutrophils spontaneously undergo apoptosis, and are therefore removed by phagocytic cells at the site of inflammation. Neutrophil apoptosis can be modulated by several factors in the local environment, such as the Fas ligand (FasL), but the molecular mechanisms involved are poorly understood. In this dissertation thesis, I describe and elucidate intracellular signalling mechanisms that are involved in regulation of spontaneous and Fas-induced apoptosis in human neutrophils. Using two different methods it was possible to detect constitutive activity of p38 mitogen-activated protein kinase (p38) in newly isolated neutrophils. The p38 survival signal was transiently lost during both spontaneous and Fas-induced apoptosis, favoured induction of the apoptotic process. During the transient loss of p38 activity there was a temporary Fas-induced increase in phosphatidylinositol 3-kinase (PI3K) activity, which also had a pro-apoptotic impact on the neutrophils. In addition, my experiments showed that the active form of p38 associates with caspase 8 and caspase 3, which is necessary for p38-induced phosphorylation of serine-362 and serine-150 on these caspases. These biochemical modifications impair the activities, and possibly also the stability, of caspase 8 and 3 and thereby weaken the capacity of these enzymes to induce apoptosis. The results in this dissertation also demonstrate that the protein phosphatase type 2A (PP2A) can directly and independently decrease the phosphorylation levels of both p38 and caspase 3. Consequently, PP2A can increase the activity of caspase 3 by dual mechanisms and thereby promote the apoptotic response in human neutrophils.
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| 4. |
- Amini, Rose-Marie, 1969-
(författare)
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Hodgkin Lymphoma : Studies of Advanced Stages, Relapses and the Relation to Non-Hodgkin Lymphomas
- 2002
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The relationship between Hodgkin lymphoma (HL) and non-Hodgkin lymphoma (NHL) is not entirely elucidated and a clonal relation may be present more often than previously believed. Mechanisms of tumour progression and resistance to therapy are poorly understood.Between 1974 and 1994 all individuals in Sweden with both HL and NHL were identified. Thirty-two cases were studied using clinical, histopathological and immunohistochemical methods. The second lymphoma often appeared in an aggressive clinical form and a significant correlation between the expression of p53 and LMP-1 in the first and second lymphoma was demonstrated.The treatment outcome for 307 patients with advanced stages of HL, in an unselected population was in accordance with the treatment results of large centres world-wide. Some patients were successfully selected for a shorter chemotherapy-regimen without inferior treatment results.In 124 patients with relapse, the survival of those primarily treated with radiotherapy according to the National guidelines was in accordance with the survival of patients of initially advanced stages. A worse outcome was found for those who received both chemotherapy and radiotherapy initially, probably because of a higher frequency of bulky disease in this group. Immunohistochemical analysis of the tumour suppressor protein p53 and retinoblastoma protein (Rb) of paired samples at diagnosis and at relapse in 81 patients did not reveal any specific staining pattern affecting survival.A novel B-cell line (U-2932) was established from a patient with a diffuse large B-cell lymphoma previously treated for advanced stage and subsequent relapses of HL. An identical rearranged IgH gene was demonstrated in tumour cells from the patient and in U-2932. A p53 point mutation was detected and over-expression of the p53 protein was found. A complex karyotype with high-level amplifications of the chromosomal regions 18q21 and 3q27, i.e. the loci for bcl-2 and bcl-6 were demonstrated.
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| 5. |
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| 6. |
- Bengtsson, Therese
(författare)
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Functional analysis of the alpha10beta1 integrin
- 2004
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The aim of this thesis was to study the function of the integrin a10b1. Integrins mediate signals between cells and their environment and regulate several cellular processes such as cell migration, proliferation and differentiation. The a10b1 integrin is expressed mainly by chondrocytes, the only cell type present in cartilage, and facilitates binding of the chondrocytes to the extracellular matrix molecule collagen. However, the function of the a10b1 integrin in cartilage is not known. In this thesis we describe the structure of the mouse a10b1 integrin gene and report the finding of two alternatively spliced extracellular forms of the a10b1 integrin. We also demonstrate the chromosomal localization of the human and mouse a10 integrin genes. To analyze the role of this collagen-binding integrin during development and in adult mice we generated a mouse deficient in the a10b1 integrin, by gene targeting deletion. We found that a10b1–null mice suffered from a mild chondrodysplasia, and that they had shorter limbs than normal mice. The mutant mice showed structural defects in the growth plate and decreased chondrocyte proliferation. Further studies have revealed that the a10b1 integrin appears to be the only collagen-binding integrin expressed in the growth plate of 8-week old mice. Together, these data show that the a10b1 integrin plays an important role in the regulation of chondrocyte function and bone development.
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| 7. |
- Berglund, Mattias, 1972-
(författare)
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Molecular Characterization of Diffuse Large B-cell Lymphoma and Aspects of Transformation
- 2004
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Lymphomas are a heterogeneous group of neoplasias originating from B- or T-lymphocytes. In this thesis, we determined the genetic and immunophenotypic characterization of DLBCL and their prognostic impact. Moreover, genomic alterations associated with the transformation to DLBCL from Hodgkin lymphoma (HL) and follicular lymphoma (FL) were elucidated. In order to outline the impact of cytogenetic as well as immunophenotypic prognostic markers in DLBCL, we firstly studied a series of 54 DLBCL tumors using comparative genomic hybridization (CGH) and we identified several frequently occurring chromosomal imbalances. Loss of 22q was more often found in the diagnostic tumors with a more advanced clinical stage, while gain of 18q21 was more commonly identified in relapses. Secondly, we correlated the expression patterns of CD10, bcl-6, IRF-4 and bcl-2 with clinical parameters in a series of 173 de novo DLBCL patients. Patients with a germinal center (GC) phenotype displayed a better survival than the non-GC group. Expression of bcl-6 and CD10 was correlated with a better survival while bcl-2 expression was associated with a poor prognosis.In approaching the HL transformation, two novel B-cell lines (U-2932 and U-2940), derived from patients with DLBCL following HL, were characterized. Interestingly, a translocation with materials from 2q and 7q as well as loss of material on 6q was found in both cell lines. For FL transformation, we assessed chromosomal alterations in a panel of 28 DLBCL patients with a previous history of FL. The DLBCL tumors displayed more chromosomal imbalances compared to FL tumors. Loss of 6q16-21 and gain of 7pter-q22 were more commonly found in the DLBCL counterparts, suggesting the chromosomal location of putative genes that may be involved in the transformation process.
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| 8. |
- Berglund, Åke, 1961-
(författare)
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Optimisation of Chemotherapy Treatment in Advanced Colorectal Cancer
- 2002
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Colorectal cancer is one of the most common malignant diseases in Sweden – more than 5000 new cases are diagnosed each year. The overall five-year survival is about 60% and in cases of recurrence the prognosis is poor.In a phase III study in advanced colorectal cancer the response rate was doubled when 5-FU was given as a bolus injection versus as a short infusion. The toxicity was similar and time to progression was longer in the injection group. However, overall survival was not significantly different. Dose-effect relationships of 5-FU were studied in another phase III study recruiting 312 patients. A decrease from 500 mg/m2 to 400 mg/m2 worsened the treatment results. A low incidence of severe toxicity was seen in both groups. An increase to 600 mg/m2 worsened the toxicity without any improvement of the results.A cytotoxic drug sensitivity test in different tumour types, mainly gastrointestinal cancer, poorly predicted treatment outcome in a phase II study.The conventional Nordic Flv regimen was split in a phase I/II trial. An escalation of dose was possible and the response rate was 20%.Thymidylate synthase (TS) and the gene expression of p53 were investigated by immunohistochemical technique in the primary tumours of 132 patients. None of the markers predicted the later palliative chemotherapy result. However, TS significantly predicted time to recurrence.Serum markers were analysed before and during FLv treatment to early predict outcomes among 87 patients. TPS is promising, both as a predictive marker before start of treatment and after a short period of treatment. In the same setting, CEA had lower predictive value. S-VEGF and S-bFGF did not yield any prognostic information of later outcome. In all studies B-haemoglobin values, performance status and subjective response were strong markers, both for prediction of objective response and for survival.
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| 9. |
- Bergqvist, Michael, 1971-
(författare)
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Radiosensitivity in lung cancer with focus on p53
- 2002
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- In Sweden approximately 2800 new lung cancer patients are diagnosed every year. Radiotherapy is used with curative intention in certain groups of patients. The aim of this thesis is to study the basis of differences in radioresistance and the possibility to predict response to radiotherapy.In the first study we investigated, using the comet assay, four lung cancer cell lines with different sensitivity towards radiation. A clear dose-response relationship for radiation-induced DNA single strand and double strand breaks were found. All cell lines showed a remarkably efficient repair of both the DNA single strand and double strand breaks one hour after irradiation. However, further studies in one radioresistant and one radiosensitive cell line demonstrated that repair during the first 15 min had the best accordance with radiosensitivity measured as surviving fraction.In the second and third study, sequencing studies of the p53 gene were performed on cell lines as well as on tumour material. Cell lines that were expressing a mutation in exon 7 were associated with increased radiosensitivity compared with tumor cell lines with mutations in other exons. In the clinical study, 10 patients were found to be mutated in the p53 gene whereas the other 10 patients were not. No correlation to clinical parameters could be drawn.In the fourth study, serum from 67 patients with a confirmed diagnosis of non-small cell lung cancer was investigated for the presence of p53 antibodies. P53 antibodies in sera, taken prior to radiation treatment, were associated with increased survival.The summary of this thesis indicates that the p53 gene has an impact on the effect of radiotherapy in lung cancer. The presence of p53 antibodies might be of clinical interest for predicting survival after radiotherapy. Further studies on the importance of the p53 gene on early repair are of interest.
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| 10. |
- Bjerner, Tomas
(författare)
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Assessment of Myocardial Perfusion with Magnetic Resonance Imaging and an Intravascular Contrast Agent
- 2001
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The intravascular contrast agent NC100150 Injection (Clariscan™) was tested for its ability to induce signal intensity changes in myocardium, both in steady state and during first pass, and thereby demarcating non-perfused myocardium from perfused. Steady state: Ex vivo in pigs and when using 4 mg Fe/kg bodyweight (b.w.) of the contrast agent, a T1-weighted inversion recovery fast spin echo (IR/TSE) sequence could demarcate 95% of the volume of non-perfused myocardium when compared with the volume determined from photographs where non-perfused myocardium was demarcated by fluorescein. A T2*-weighted gradient echo sequence resulted in significantly lower volume estimations of non-perfused myocardium. Under similar conditions and when using 5 mg Fe/kg b.w., a T2-weighted fast spin echo (TSE) demarcated 99% of the volume of non-perfused myocardium. We were not able to implement the IR/TSE sequence in vivo, but the T2-weighted TSE resulted in clear visualization of non-perfused myocardium in vivo in animals. First pass: With a single-shot T2-TSE, one slice was acquired every heartbeat during the first pass of the contrast agent. When using this sequence, non-perfused myocardium was demarcated in animals and the induced signal intensity changes in perfused myocardium (74±18% @ 5 mg Fe/kg b.w.) were comparable to those in patients (59±13 @ 3 mg Fe/kg b.w.), when taking differences in doses into account. Linear dose–response was found in porcine myocardium between R1, R2, and R2* versus dose (0 – 12 mg Fe/kg b.w.) ex vivo and for R1 (in myocardium and blood) versus dose (0 – 5 mg Fe/kg b.w.) in vivo. However, R1 determination in vivo and in the box ex vivo indicated that blood loss (<2/3) from the myocardium occured during the excision of the heart and preparation for the box, meaning that the box situation ex vivo actually corresponds to lower doses in vivo. Finally, the in vivo measurements of R1 in myocardium and blood indicated that at R1 values in blood as high as 13 s-1, the water exchange is in the fast regime through the capillary wall. In conclusion, the feasibility of NC100150 Injection, in steady state and during first pass, for demarcation of non-perfused myocardium when using a T2-weighted TSE sequence has been demonstrated.
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