| 1. |
- Handin, Niklas
(författare)
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Proteomics informed investigation of human hepatocytes and liver tissue
- 2021
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- A successful drug needs to display beneficial absorption, distribution, metabolism, excretion and toxicity (ADME-Tox) profile. It is therefore important to investigate these properties during the drug discovery process. The liver is of particular interest in ADME-Tox studies, as it is highly metabolically active and oral administrated drugs needs to pass the liver before reaching the systemic circulation. However, a dose of a drug that is efficacious and safe for one individual may be inefficacious or toxic, because of inter-individual variability. Therefore, it is important to investigate the ADME-Tox properties in a sufficiently large population. Investigations on ADME-Tox is usually done in in vitro cell models. Therefore, a variety of models to simulate liver functions have been developed and ranging from subcellular microsomes to complex 3D organoid cultures. This thesis investigates variability of ADME proteins in human liver tissue and in liver cell models.First, mass spectrometry based targeted proteomics was used to quantify ADME relevant proteins from 149 human liver samples. The observed inter-individual protein variability could not solely be explained by genotype. Therefore, a single transporter protein, the bile and drug transporting protein, NTCP, was investigate in detail. Non-genetic factors, e.g. smoking and alcohol consumption, and epigenetic factors such as DNA methylation, were found to contribute to the observed inter-individual variability of NTCP. Next, hepatocytes (PHH) were isolated from 54 human livers tissues and after which the hepatocytes where cryopreserved. The variable attachment efficiency of cryopreserved hepatocytes where investigated and an apoptosis inhibition protocol for restoration of attachment properties was developed. This protocol was also successfully applied to 3D cultured PHH spheroids resulting in increased ability to form 3D spheroids. The effect of culture conditions on the quality of the 3D cultures was also investigated. 3D PHH spheroids were formed and maintained in different, commonly used culture media. The spheroids were characterized by a variety of functional assays including global proteomics. The proteome analysis showed that while no epithelial to mesenchymal transitions was observed, 3D cultures maintained in fasting glucose and insulin levels resembling the in vivo situation showed a more liver-like phenotype with a high expression of ADME proteins and functional cytochrome P450 metabolism. Transporter kinetics were also investigated in the 3D cultured PHH. Finally, we investigated if global proteomics data from 56 human liver tissues could be deconvoluted to give information about the liver composition. The cell type proportions generated by deconvolution where similar to literature values. Liver samples that displayed deviating cell composition were identified. The deviating liver compositions were in agreement with clinical markers of inflammation in the patient´s blood samples and with altered extracellular matrix protein composition, comparable to that found in liver steatosis. In conclusion, this thesis have investigated variability in ADME proteins in human liver and in in vitro cultures of human hepatocytes, characterized cofounding factors for in vitro cultured hepatocytes and further extended drug disposition studies in 3D cultured hepatocytes.
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| 2. |
- Hansson, Johan, 1964-
(författare)
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Loco-regional Treatment of Peritoneal Carcinomatosis: Survival, Morbidity and Quality of Life
- 2009
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Peritoneal carcinomatosis (PC) is traditionally regarded as a terminal stage of disease with a poor prognosis and systemic chemotherapy is regarded as palliative treatment. In order to improve survival and even to achieve cure for selected patients with PC, cytoreductive surgery and intraperitoneal che-motherapy have been advocated. Despite complete macroscopic removal of tumour, residual microscopic malignant cells might result in recurrence. Intraperitoneal chemotherapy aims to kill residual malignant cells and thereby needs to be distributed in the entire peritoneal cavity. This aggres-sive combined loco-regional treatment has a high risk of morbidity and mor-tality. Whether the increased risks are acceptable to improve survival re-quires investigation and the impact of loco-regional treatment of PC on health-related quality of life (HRQL) needs to bee explored The overall aim of this thesis was to analyse the impact of cytoreductive surgery and intraperitoneal chemotherapy on patients with peritoneal carci-nomatosis. A significant survival improvement (median 32 months) was seen in 18 patients with PC of colorectal origin subjected to loco-regional treatment, in comparison to matched controls treated with systemic chemotherapy (me-dian survival 14 months, Paper I). The results of single-photon emission computer-tomography (SPECT) in 51 patients were correlated to the number of intraperitoneal chemotherapy courses that could be performed without further surgery (Paper II). Postoperative 30-days morbidity and 90-days mortality was investigated in 123 PC-patients after loco-regional treatment. Severe adverse events occurred in 51 (41%) patients. Five patients (4%) had treatment-related mortality. Stoma formation, duration of surgery, periopera-tive blood loss, and extent of PC was associated with morbidity (Paper III). HRQL was investigated in 64 patients. HRQL was negatively affected at 3 months but a partial recovery was seen at 8 months. 30-day morbidity did not have any impact on HRQL at 8 months (Paper IV). This treatment there fore appears justified despite considerable toxicity in view of possible life prolongation.
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| 3. |
- Österlund, Emerik, 1995-
(författare)
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Prognostic and Predictive Factors in Metastatic Colorectal Cancer
- 2024
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The outcome for metastatic colorectal cancer (mCRC) patients has improved substantially in recent decades. This has chiefly been observed in study populations, and predominantly in left-sided primary tumours, which is why we wanted to study if and how survival has improved in the background population. It has also been seen that certain molecular subtypes are more common in population-based materials, and, thus, we studied the prevalence and effects of different molecular alterations.Paper I is a national population-based material of all 19 566 Swedish patients with a diagnosis of mCRC 2007-2016, 55% were male and 70% had synchronous metastases. Median overall survival (OS) for all patients was 14.0 months. An improvement could be seen over time, also in stratified analyses. OS was influenced by presentation of metastases, age, primary tumour location, and sex. All except sex remained statistically significant in a multivariable analysis. Differences of about one month in median OS were seen between healthcare regions, but these diminished over time.Paper II included all 765 patients from the Uppsala Region with a mCRC diagnosis 2010-2020. Right colon primary tumours were seen in 38%, left colon in 27% and rectum in 34%. BRAF-V600E mutations (mt) and deficient mismatch repair (dMMR) had a poor OS and were more common in right colon primary tumours. Primary tumour location did not affect OS in subgroups according to mutations in RAS or BRAF, nor in a multivariable analysis. Molecular alterations seem to be more important than primary tumour location for prognosis.Paper III studied KRAS-G12Cmt in three population-based and one real-world material. KRAS-G12C was seen in 2-4% of all tested and in 4-8% of all KRASmt. No differences in patient characteristics were observed between KRAS-G12C and other KRASmt. No differences in OS were seen between KRAS-G12C and other KRASmt, neither for all patients, nor in different treatment groups.Paper IV studied atypical BRAFmt (aBRAFmt) in two population-based and one real-world cohort. aBRAFmt was seen in 1-4% of the adequately tested patients in the different cohorts. aBRAFmt patients were predominantly male, had dMMR less often, more rectal primary tumours, and less peritoneal metastases compared with BRAF-V600Emt. Serrated adenocarcinomas were seen in about half of the aBRAFmt. OS was significantly better for aBRAFmt than in BRAF-V600Emt, but worse than for RASmt and RAS&BRAFwt patients. Nine aBRAFmt received epidermal growth factor receptor inhibitors without responses.
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| 4. |
- Bengtsson, Mattias
(författare)
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Att lämna en placering i samhällsvård : En studie om ungas övergång från samhällsvård till vuxenliv
- 2022
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The focus in this thesis is young peoples’ (aged 17–20) experiences of leaving out-of-home care (OHC) and making the transition into adulthood. Prior research shows care leavers as a vulnerable group making the transition to adulthood at younger age, in shorter duration and with less support than their peers. The overarching aim is to gain knowledge of how young care leavers experience and handle their transition from OHC to adulthood, and how their experiences and strategies change over time. The study design is longitudinal with three waves of interviews: when still in care (T1), 6–11 months later when most of them had left care (T2) and another 10–19 months later (T3). Article I focuses the informants’ (n=15) expectations for their future and how these are changing over time (T1–T2). The participants’ short term expectations are characterized by worries (T1) and ambivalence (T2) – their long-term expectations are more optimistic (both T1 and T2) and tend to be guided by normative developmental patterns. The aim of article II is to study care leavers’ (n=20) strategies for handling adversities during their OHC transition. The results show that the participants over time (T1–T2) develop externally oriented strategies by navigating towards available resources, and internally oriented reflexive strategies for re-negotiating the meaning of their earlier experiences. Departing from an agency perspective article III focuses care leavers’ (n=14) transitional patterns of leaving care (T1–T3). Three patterns are identified: one stable long-term future oriented, one unstable short-term future oriented and one ambivalent pattern shuttling between long- and short-term future orientations. The aim in article IV is to study occupational trajectories, i.e. care leavers’ (n=14) paths into education and employment from a theoretical framework of agency vs. structure. The results show three ideal types of trajectories where agency is: (1) facilitated by structure, (2) perceived as free from structural constraints, and (3) hindered by structural constraints. The longitudinal design provides an original contribution the field of study by uncovering how care leavers’ expectations for their future is changing during the process of transition, how increasingly successful strategies are developed over time, and how transitional OHC patterns are influenced by the agents’ time horizons as well as by structural forces. A conclusion from the study is that societal support targeting young care leavers is deficient and needs to be developed and strengthened. Furthermore, the transition could be facilitated by extending the duration of the transition process, by including care leavers as active participating agents in the planning process of their passage out from OHC, and by strengthening the maintenance of care leavers’ relationships to supportive members in their formal and informal network. ”Independence” as the ultimate goal for young people leaving OHC is criticized based on the results showing that interdependent relationships to significant others is an integrated part of care leavers’ perception of adult life.
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| 5. |
- Karlsson, Henning, 1985-
(författare)
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New preclinical strategies for characterization and development of anticancer drugs
- 2017
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Increased understanding of the molecular mechanisms underlying cancer development has shifted drug discovery towards target driven drug development the last decades, but the development of effective cancer drugs has been hampered by the lack of predictive preclinical models. 3-D cultures, considered to more accurately reflect solid tumors in vivo, have been proposed as one way to increase the predictability of clinical efficacy in cancer drug discovery and development.The aims of this thesis were to improve preclinical models for cancer drug development, with focus on colorectal cancer (CRC) and use of multicellular tumor spheroids (MCTS), and also to mechanistically characterize some potentially new anticancer drugs (papers I – IV). The most important technical improvement was the development of direct measurement of green fluorescent protein (GFP) marked cells in spheroids, simplifying live collection of viability data and enabling high-throughput screening (HTS) in the MCTS model (paper I). In paper III and IV, the 3-D model was adapted to enable studies on the interaction between drugs and radiation. Two potentially new anticancer drugs, VLX50 and VLX60, were mechanistically characterized. VLX60, a novel copper containing thiosemicarbazone, induced reactive oxygen species (ROS) formation, was selectively active against BRAF mutated colon cancer cells and exhibited anticancer activity in vivo (paper II). Furthermore, two potentially new anticancer drugs were found suitable for further development for use in combination with radiation (papers III and IV). In paper III, synergy with radiation in spheroids compared to monolayer cultured colon cancer cells was shown with the novel iron-chelating inhibitor of oxidative phosphorylation, VLX600. In paper IV, the antiprotozoal drug nitazoxanide was shown to sensitize quiescent clonogenic colon cancer cells to radiation.In conclusion, introduction of measurement of fluorescence of GFP marked cells in spheroids makes clinically relevant 3-D models feasible for HTS experiments and characterization of candidate drugs and radiosensitizers in early cancer drug discovery and development. VLX60 has several characteristics suitable for further development into a cancer drug, notably against BRAF mutated colorectal cancer cells. VLX600 and nitazoxanide show radiosensitizing properties making them promising for further development for use as cancer drugs in combination with radiation.
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| 6. |
- Senkowski, Wojciech
(författare)
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High-throughput screening using multicellular tumor spheroids to reveal and exploit tumor-specific vulnerabilities
- 2017
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- High-throughput drug screening (HTS) in live cells is often a vital part of the preclinical anticancer drug discovery process. So far, two-dimensional (2D) monolayer cell cultures have been the most prevalent model in HTS endeavors. However, 2D cell cultures often fail to recapitulate the complex microenvironments of in vivo tumors. Monolayer cultures are highly proliferative and generally do not contain quiescent cells, thought to be one of the main reasons for the anticancer therapy failure in clinic. Thus, there is a need for in vitro cellular models that would increase predictive value of preclinical research results. The utilization of more complex three-dimensional (3D) cell cultures, such as multicellular tumor spheroids (MCTS), which contain both proliferating and quiescent cells, has therefore been proposed. However, difficult handling and high costs still pose significant hurdles for application of MCTS for HTS.In this work, we aimed to develop novel assays to apply MCTS for HTS and drug evaluation. We also set out to identify cellular processes that could be targeted to selectively eradicate quiescent cancer cells. In Paper I, we developed a novel MCTS-based HTS assay and found that nutrient-deprived and hypoxic cancer cells are selectively vulnerable to treatment with inhibitors of mitochondrial oxidative phosphorylation (OXPHOS). We also identified nitazoxanide, an FDA-approved anthelmintic agent, to act as an OXPHOS inhibitor and to potentiate the effects of standard chemotherapy in vivo. Subsequently, in Paper II we applied the high-throughput gene-expression profiling method for MCTS-based drug screening. This led to discovery that quiescent cells up-regulate the mevalonate pathway upon OXPHOS inhibition and that the combination of OXPHOS inhibitors and mevalonate pathway inhibitors (statins) results in synergistic toxicity in this cell population. In Paper III, we developed a novel spheroid-based drug combination-screening platform and identified a set of molecules that synergize with nitazoxanide to eradicate quiescent cancer cells. Finally, in Paper IV, we applied our MCTS-based methods to evaluate the effects of phosphodiesterase (PDE) inhibitors in PDE3A-expressing cell lines.In summary, this work illustrates how MCTS-based HTS yields potential to reveal and exploit previously unrecognized tumor-specific vulnerabilities. It also underscores the importance of cell culture conditions in preclinical drug discovery endeavors.
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| 7. |
- Forslund, Marina
(författare)
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A nutrition intervention in men with prostate cancer : Exploring effects on bowel symptoms from radiotherapy, patient experience, and nutrient intake
- 2020
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Objective The main objective of this thesis was to explore the effects of a nutrition intervention on acute and late bowel symptoms in men with localised prostate cancer treated with pelvic radiotherapy (study I), participants’ experiences from receiving the nutrition intervention (study II), and associations with nutrient intakes (study III).Methods A total of 180 men with localised prostate cancer referred to curative radiotherapy targeting the prostate gland and pelvic lymph nodes were recruited to the trial. The participants were randomised to standard care plus a nutrition intervention aiming to modify fibre and lactose intakes (NIG; n=92) or standard care alone (SCG; n=88). Data on bowel symptoms and dietary intake were collected pre-treatment and at seven time points during a 26-month study period. Analyses of the effects of the nutrition intervention on bowel symptoms were conducted for the acute phase (up to 2 months post radiotherapy), and the late phase (7 to 24 months post radiotherapy). Semi-structured interviews were conducted with 15 participants from the NIG to explore experiences of the nutrition intervention.Results The nutrition intervention was associated with statistically significantly, but not clinically significantly, less bother from blood in stools and flatulence during the acute phase. The nutrition intervention was also associated with more bloated abdomen during the late phase (Study I). Social support, contributing to the greater good, prior knowledge, dietary information, and a small need for change facilitated adherence. While feeling limited, wanting to decide for themselves, the timing of the intervention, unmet expectations, and loss of motivation were described as barriers for adherence (Study II). A greater reduction of lactose was associated with decreased intake of calcium at the end of the radiotherapy period. A more modified fibre intake during the radiotherapy period was associated with increased vitamin C, but decreased selenium intake (Study III).Conclusions The effects from the nutrition intervention were small and inconclusive and do not support routine dietary advice aiming to modify fibre and lactose intakes as a mean to substantially reduce adverse effects from pelvic radiotherapy. Tailored nutritional interventions based on individual preferences, prior knowledge, and context, could enhance adherence. There were few associations between modified fibre and lactose intakes and nutrient intakes, thus, no recommendations can be made on whether such dietary advice should continue to be provided to men with prostate cancer undergoing pelvic radiotherapy.
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| 8. |
- Godskesen, Tove
(författare)
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Patients in Clinical Cancer Trials : Understanding, Motivation and Hope
- 2015
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The overall aim of this thesis was to study participants' understanding of clinical cancer trials, and their motivation for participation. Of particular interest was the question of whether the patients hoped for a cure resulting from the trial. The thesis was based on four studies and used three methods: interviews, a questionnaire, and empirical bioethics. The results of Study I indicated that the participants in phase 1 trials understood most of the information provided, but were unaware of both the very small potential for treatment benefit, and the risk of harm. Patients in phase 3 trials had a good understanding of the trial, except regarding side effects and their right to withdraw. Some found it hard to ask questions and felt they needed more information (Study III). The participants in phase 1 trials were strongly motivated by the generally unrealistic hope for therapeutic benefit (Study I). When the chances of a cure are minuscule, as for participants with end-stage cancer in phase 1 trials, hope can play an important, positive role and offer meaning to one’s remaining life. However, hope for an unrealistic outcome could also deprive patients of an opportunity to spend their remaining lives, as they would otherwise choose (Study II). The participants in phase 3 trials indicated that their motivation for participation was multifaceted; the most common motivations included hope of therapeutic benefit, altruism, access to extra clinical examinations or better care, and a wish to repay society for the help they had received (Study III). After stratifying and analysing the motivation data by gender, age, education and previous experience of trial participation, males and those aged ≥65 years were significantly more motivated to participate out of a desire to reciprocate the help they had received, either because of a sense of duty or because their families or friends considered that they should attend (Study IV). In conclusion, the informed consent process seems to work relatively well, with good results within most subgroups. However, patients with end-stage cancer who are participating in phase 1 trials are a vulnerable group as they have very little potential for treatment benefit coupled with a tangible risk of harm.
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| 9. |
- Jakobsson Larsson, Birgitta, 1965-
(författare)
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Quality of life, Coping and need for Support during the ALS disease trajectory
- 2016
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The overall aim of this thesis was to investigate quality of life, coping and emotional distress (i.e. anxiety and depression) among newly diagnosed ALS patients. An additional aim was also to investigate relatives’ experiences of the care for the patient and the support they received for themselves during the disease progression.The most nominated areas of importance for the patient’s overall QoL were family, friends and own physical health. Most patients rated their QoL as good, which did not change at subsequent measurement, despite their physical function having changed for the worse during disease progression. Some patients had symptoms of clinical anxiety and depression during the first year after diagnosis. The total quality of life score did not correlate with physical function but with depression early on after diagnosis. Most patients used support and independence as strategies to cope with the disease during the first six months after diagnosis. There were few changes early on after the diagnosis, and the patients used several different strategies. The results show that the use of coping strategies remained stable over time. Both physical function and emotional distress correlated significant with different coping strategies, with some variation during the disease progression. Relatives experienced the care of their loved one as positive and based on the patient’s needs and desires. The treatment, knowledge, support and help from the staff were important for the relatives’ feeling of security. Different factors influence the use of support for themselves. The relatives did not think of their own needs, but their focus was rather on the patient.The results of the thesis highlight the importance of providing support both to patients and their relatives during the disease progression. With early and regular evaluation on quality of life, coping and emotional well-being among the patients, the health professionals may be able to support the patients based on their specific needs, which probably will increase their quality of life.
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| 10. |
- Gullbo, Joachim, 1971-
(författare)
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Preclinical Development of New Alkylating Oligopeptides for Cancer Therapy
- 2003
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Oligopeptides can be used to carry cytotoxic agents in cancer chemotherapy, using tumour-associated proteins as the molecular target for selectivity. During the seventies and eighties Peptichemio, a cocktail of six alkylating oligopeptides carrying m-L-sarcolysin, was investigated in a wide variety of human malignancies. Positive clinical results were suggested to result from rapid and effective DNA-crosslinking following uptake in neoplastic cells, but also from antimetabolic properties of the drug. Although m-L-sarcolysin never reached widespread clinical use, the well established para-isomer melphalan still, after nearly fifty years, has a place in cancer chemotherapy.The present study was undertaken to synthesise the melphalan containing analogue of the tripeptide P2 (L-prolyl-m-L-sarcolysyl-p-L-fluorophenylalanine ethyl ester, the main contributor to Peptichemio’s activity) and similar compounds, preferably dipeptides. The new compounds compared favourably with melphalan, m-L-sarcolysin and P2, considering their potency in vitro. Structure activity relationship analysis showed that the activity of melphalan dipeptides depended on the amino acid composition, sequence and end group modifications, but only to a minor degree on lipophilicity. Results suggested that the dipeptides, to exert their full cytotoxic activity, had to interact with specific biomolecules such as dipeptide transporters or peptidases. Although no active transport could be demonstrated the influence of peptide hydrolysis was obvious, thereby suggesting a rationale for increased activity as well as potential tumour selectivity in comparison with melphalan.Preliminary in vivo studies in mice supported the results, despite equal alkylating capacity the dipeptide J1 (melphalanyl-p-L-fluorophenylalanine ethyl ester) and the tripeptide J3 (L-prolyl-melphalanyl-p-L-fluorophenylalanine ethyl ester) were more active than was melphalan on human tumour cells implanted in test animals although all drugs produced expected side effects, notably leukopenia, of similar magnitude.In conclusion, oligopeptide derivatives of melphalan seem to provide improved cytotoxic activity and therapeutic index. Further development of such oligopeptides for clinical use seems worthwhile.
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