1.
Andersson, Håkan, 1944
(författare)
Radioimmunotherapy of experimental ovarian cancer with Astatine-211. An in vivo model for consolidation treatment in women
2000
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
2.
Dannaeus, Karin
(författare)
Studies on myeloid differentiation: cytokine influence and identification of a novel marker gene
2000
Doktorsavhandling (övrigt vetenskapligt/konstnärligt) abstract
Hematopoiesis is a highly complex process by which a range of specialized blood cells are generated from a small pool of multipotent stem cells in the bone marrow. The survival, proliferation, and differentiation of hematopoietic stem cells are tightly regulated by both soluble and membrane-bound cytokines produced within the bone marrow microenvironment. Kit Ligand (KL) and Flt3 Ligand (FL) are two important hematopoietic cytokines, and signal via related tyrosine kinase receptors; c-kit and flt3. The first part of this thesis is focused on the influence of KL and FL on differentiation of a stem and progenitor cell-enriched cell population (c-kit+Lin- cells), isolated from mouse bone marrow. We found that KL and FL have different effects, and favor development of granulocytic and monocytic cells, respectively. A clear discrepancy was also seen on the expansion of multilineage progenitors (pre-CFCmulti) and granulocyte/macrophage colony-forming progenitors (CFC-G/M) which was strongly favored by KL. Furthermore, FL induced development of a biphenotypic cell population coexpressing monocytic and B-cell characteristics, restricted to the macrophage lineage. The second part of this thesis, describes the identification and characterization of a novel myeloid-associated differentiation marker gene (MYADM) which is preferentially expressed in myeloid cells, but absent in B and T lymphocytes. The predicted 32-kDa protein contains eight transmembrane domains and localizes to intracellular membranes. Although, the function of MYADM is unknown, antisense oligonucleotides inhibit colony formation of c-kit+Lin- cells, suggesting an important role for MYADM in myeloid differentiation. To gain further insight into the transcriptional control of the MYADM gene, we have analyzed a 1.5-kb sequence upstream the transcription start site for promoter activity in myeloid and lymphoid cells. We conclude that the sequence analyzed in this study does not confer the promoter tissue-specificity, thus additional regulatory elements may be located outside the region upon which this study has concentrated.
3.
Ejeskär, Katarina, 1969
(författare)
Genetic alterations in Scandinavian neuroblastoma tumors
2000
Doktorsavhandling (övrigt vetenskapligt/konstnärligt) abstract
The results presented here derive from our efforts to find genes and chromosomal regions of interest in the formation and progression of the childhood tumor neuroblastoma.Neuroblastoma is the most common extracranial solid tumor of childhood. It is a tumor of the postganglionic sympathetic nervous system, and clinically, the hallmark of neuroblastoma is its heterogeneity.In order to characterize chromosomal regions of interest the methods loss of heterozygozity (LOH) studies using PCR-based polymorphic markers, representational difference analysis (RDA), somatic cell hybrid mapping, fluorescent in situ hybridization (FISH), radiation hybrid mapping and physical mapping by construction of a BAC-contig have been used. For mutation analysis of genes the methods single strand conformation polymorphism (SSCP), heteroduplex (HD) and DNA-sequencing have been used, and the expression studies of candidate genes have been performed using RT-PCR.In the Scandinavian neuroblastoma tumor material we have been able to show that deletions of chromosome arm 3p is the second most common deleted chromosomal region (16%) next to 1p (22%). We could also see a difference in clinical outcome between patients with tumors displaying deletion of the entire chromosome 3 versus the ones with tumors displaying deletions of region 3p only. The ones with 3p-deletion have all died of disease whereas the ones with entire chromosome 3 loss are alive and well. We have also characterized a region on chromosome 1, 1p36, shown, by others and us, to be commonly deleted in neuroblastoma tumors. A critical region of app. 25 cM between genetic markers D1S80 and D1S244 could be defined. We have also by using combined LOH-data from both neuroblastoma and germ cell tumors defined a region of common deletion for both tumor types, this region could be defined by markers D1S508 and D1S244 and is app. 5 cM.Also some 1p36 putative tumor suppressor genes, i.e. CDC2L1, TP73 and CORT, have been fine mapped and tested for expression and mutations in neuroblastomas. No evidence for any of them to be the 1p36 neuroblastoma tumor suppressor gene has however been discovered.
4.
Engarås, Boel, 1949
(författare)
Characteristics of tumour markers CEA, CA 50 and CA 242 in serum with reference to colorectal cancer
2000
Doktorsavhandling (övrigt vetenskapligt/konstnärligt) abstract
There is no consensus on if and how to conduct colorectal cancer surveillance. Serum levels of tumour markers and especially CEA increase before a recurrence is detected by clinical diagnosis. Second look surgery based on elevated serum levels of CEA has been beneficial for individual patients. Due to inconsistent findings, CEA-measurements after curative surgery hold a low grade of recommendation.The aim of the present study was to identify better surveillance tools using tumour markers for indicating relapsing colorectal cancer. Standard levels and fluctuation in cancer-free individuals in an age group where cancers are likely to occur were unknown, as was the influence of surgery in cancer-free patients undergoing surgery for benign disease and in patients surviving colorectal cancer. The aim was to establish those serum levels of CEA, CA 50 and CA 242. Based on these findings, individual cut-off levels of markers were to be identified. Also levels of CEA and CA 242 in future cancer patients were to be measured.It was found that the 90th percentile (chosen as standard level) of serum levels of CEA, CA 50 and CA 242 were 5,6 ng/ml, U/ml and 25 U/ml respectively. Serum-levels of CEA were higher in smokers and also increased with age. The fluctuation was below 20% for all markers. There was a transient decline in serum levels of CEA after surgery and they had not recovered until one year after the surgical procedure. Patients surviving colorectal cancer had a similar decline. In the post-operative period there was a positive relation between CEA levels and an inverse relation between CA 242 levels and Dukes´ staging in the patients surviving colorectal cancer. With individual cut-off levels all hepatic metastases occurring during the test period (two years after surgery) were indicated by CEA (0-19) months before they were clinically detected. In total twenty-four recurrences were detected during the test period. Twenty-one (88%) were indicated by CEA, eleven by CA 50 (46%) and nineteen (79%) by CA 242 (individual cut-off). Serum levels of CEA and CA 242 were highest close to cancer diagnosis
5.
Fransson, Per
(författare)
Quality of life and side effects in patients with localized prostate cancer : evaluation with self-assessment questionnaires
2000
Doktorsavhandling (övrigt vetenskapligt/konstnärligt) abstract
Localized prostate cancer (LPC) is predominantly a tumor among older men, and few patients will get symptoms from the disease. All methods to treat LPC with a curative intent have different types and degrees of side effects. It is therefore very important to evaluate the side effects thoroughly to make sure that treatment complications will not decrease the quality of life more than the disease would have done. In search for new and better treatments, complications has to be registered and evaluated in relation to quality of life (QOL) for the patients. Few validated self-assessment questionnaires for evaluation of external radiotherapy (EBRT) induced side effects has yet been developed. The present project focus on the development of the PC-specific questionnaire, QUFW94, and evaluation of symptoms in patients treated with EBRT and un-treated (watchful waiting) patients with a LPC.In the newly developed LPC-specific questionnaire a reliability and responsiveness test was performed. Both the inter-rater test and the test-retest show high correlation coefficients (ICC), above 0.60 for all scales. The internal reliability exceeded the lower acceptable limit (Cronbach a >0.70). The questionnaire was proven to be valid for the evaluations of EBRT side effects in LPC patients.Late side effects were evaluated 4 years after treatment in 181 LPC patients, treated with conventional large field EBRT, and compared with 141 age-matched PC disease free men. The most prominent urinary side effects were urgency and leakage which were doubled in the patient group. A ten fold increase was seen in comparison to controls at the most prominent intestinal problems, blood, mucus and leakage. The results support the use 3-D conformai therapy to decrease irradiation dose to the rectum and the bladder and thereby decreased side effects. A prospective additional evaluation 8 years after EBRT did not show any changes in urinary problems between 4 and 8-yr follow-up in the patients or the controls.EBRT of LPC is also accompanied by disturbances in sexual function. These problems were therefore evaluated, 4 years after EBRT, in relation to the function in PC free men. Patients treated with EBRT indicated higher levels of sexual dysfunction than age-matched controls. No erection was reported from 12% of the control subjects, 56% of the patients who had only received radiotherapy (RT) and 87% of the RT+castration (RT+A) patients. The extended evaluation 8 years after EBRT show similar sexual function in all groups.QOL and late side effects/symptoms were evaluated in the first and only randomized trial between RT and deferred treatment (DT) and compared to age-matched controls. QOL was evaluated with the general QOL formula, EORTC's QLQ-C30 (+3), and LPC specific side effects with QUFW94 in 108 randomized patients with LPC 3 years after diagnosis. Social functioning was the only QOL scale where a significant difference was found between the two patient groups and in comparison with the control group. Multivariate regression analysis showed that hematuria, incontinence, mucus, and planning of the daily activities due to intestinal problems caused this decrease in QOL in the RT group. In conclusion, the LPC specific QUFW94 questionnaire was proven to be valid for evaluation of side effects and showed increased intestinal problems in the patients treated with conventional large field EBRT in comparison to untreated LPC patients. No difference in urinary and intestinal late side effects or sexual function was seen between a 4 year vs. 8 year follow-up.
6.
Höglund, Erik
(författare)
DNA fragmentation in cultured cells exposed to high linear energy transfer radiation
2000
Doktorsavhandling (övrigt vetenskapligt/konstnärligt) abstract
The DNA double-strand break (DSB) is a critical lesion which, if not completely restored, can have serious biological consequences. The relative biological effectiveness (RBE) of many severe end-points are closely related to radiation quality, with increased effectiveness at elevated ionization density. Data presented provide information about the influence of radiation quality on the initial processes causing DNA damage, and the mechanisms leading to its restoration. Such information will increase the understanding of radiation action mechanisms in mammalian cells. Human cells were irradiated with accelerated ions having linear energy transfer (LET) values in the range 40-225 keV/μm, and 60Co-photons. Detailed analyses of the DNA fragment distributions were performed in the size-range 5 kilobasepairs to 6 megabasepairs by pulsed-field gel electrophoresis. A non-random fragmentation of DNA was evident, with an elevated number of small and medium-sized fragments for ion irradiation, and the total number of breaks increased by 80-110% when these fragments were included in the analyses. The RBE for DSB induction was 1.2-1.5. A two-fold increase of the number of breaks induced per nitrogen ion passing the cell nuclues was found when LET was increased from 80 to 225 keV/μm, indicating a possible role of particle track structure in DSB induction. Furthermore, the ability to repair DNA was closely related to radiation quality, with an increased proportion of unrejoined breaks for densely ionizing radiation. Surprisingly, the majority of breaks were rapidly rejoined even following exposure to high-LET radiation. The proportion of breaks restored by the slow phase showed a five-fold increase for the highest LET tested, compared with photons. The results presented nominates the complexity of breaks as one determining factor for reduced reparability reported following high-LET exposure.
7.
Jerkeman, Mats
(författare)
Aggressive lymphoma
2000
Doktorsavhandling (övrigt vetenskapligt/konstnärligt) abstract
Aggressive lymphoma is a rapidly growing tumour of lymphocyte origin, potentially curable with chemotherapy. In a trial by the Nordic Lymphoma Group, 405 patients with aggressive lymphoma were included, and randomised to receive either the standard chemotherapy regimen, CHOP, or a weekly multidrug regimen, MACOP-B. In this trial, MACOP-B was not superior in terms of response, failure-free or overall survival, but was associated with more non-haematological toxicity and with more pronounced negative effects on health-related quality of life (HRQOL). In this study, we were able to validate the prognostic impact of the International Prognostic Index (IPI). In 92 patients, assessment of HRQOL was performed before, during, and after chemotherapy. In this population, chemotherapy was associated with relatively little negative impact on HRQOL, compared to a reference population. In a multivariate analysis of prognostic factors, pre-treatment global quality was identified as an independent prognostic factor. In 259 patients, immunohistochemical analysis of Ki-67, BCL2, p53 and P-glycoprotein was performed. In a multivariate model, high BCL2 expression, high p53 expression and both very high and low Ki-67 expression were associated with poor prognosis, and were shown to provide additional prognostic information to the IPI. Assessment of BCL2 is proposed to be included as a routine procedure in patients with aggressive lymphoma. In 32 patients with diffuse large B-cell lymphoma (DLBL), frozen lymphoma tissue was available, enabling assessment of BCL6 rearrangement with Southern blot. BCL6 rearrangement was detected in six of 50 patients (12%) and among these, a trend towards superior overall and failure-free survival was noted. In a consecutive series of 81 patients with cytogenetically analysed DLBL, the prognostic impact of cytogenetic aberrations of previously proposed prognostic importance, was analysed. In univariate analysis, der(1q)(21-23), was associated with inferior overall survival. Among patients receiving anthracyclin-based chemotherapy, der(1q)(21-23) remained an adverse prognostic factor in a multivariate analysis, stratified for IPI. The implications of these results in relation to current findings in prognostication and treatment of patients with aggressive lymphoma is discussed.
8.
Jönsson, Marzieh
(författare)
Wnt-5a Signalling in Human Mammary Cells: Implications for the Development of Breast Cancer
2000
Doktorsavhandling (övrigt vetenskapligt/konstnärligt) abstract
The Wnt-5a gene encodes a secreted protein that regulates several normal processes in embryonic and adult tissues by as yet unknown mechanisms. Expression of Wnt-5a protein does not cause cell transformation, but it instead counteracts the effects induced by transforming Wnts. Inasmuch as Wnt-5a can activate the Wnt/beta-catenin signalling pathway, we performed experiments to determine whether molecules participating in this pathway were modified in breast tumours. Thirteen percent of the tumours we studied showed accumulation of beta-catenin protein but no mutations in the beta-catenin gene or defects in APC protein. Moreover, the human dishevelled gene (DVL-3) was rarely activated in the examined tumours. To elucidate the mechanisms of action of Wnt-5a, we studied the response of breast epithelial cells to overexpression or inhibition of this protein. Our results demonstrate that Wnt-5a is a co-factor that is needed to activate the collagen-binding discoidin domain receptor 1. In addition, the Wnt-5a protein exhibited activities involved in positive regulation of cell adhesion and negative regulation of cell migration. To determine whether the biological activities of Wnt-5a are linked to the development of breast cancer, we evaluated levels of this protein in invasive breast tumours. We found that expression of Wnt-5a had been lost in 44% of the studied carcinomas. This loss was significantly associated with higher histological grade and absence of estrogen and progesterone receptors, and proved to be an independent and powerful predictor of early relapse. Thus our data support the notion that Wnt-5a is a tumour suppressor, and that lack of this protein increases the risk of recurrent breast disease.
