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- Andersson, Britta, 1979-
(författare)
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Manipulation of potassium ion fluxes to induce apoptosis in lung cancer cells
- 2007
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Apoptosis is a special form of cell death that if non-functional may lead to diseases such as cancer. A reduction of the intracellular potassium ion (K+) content is necessary for activating enzymes important for the execution of apoptosis. Pharmacological modulation of K+ fluxes to reduce intracellular K+ in cancer cells might therefore force the cells into apoptosis and decrease tumour cell mass. Human malignant pleural mesothelioma (MPM) is a form of cancer often caused by asbestos exposure. Although asbestos has been banned in the Western World, the incidence of MPM is expected to increase. Cisplatin is the first-line chemotherapy for MPM, but acquired resistance to the drug is a clinical problem. This thesis is mainly based on work with the human malignant pleural mesothelioma cell line (P31 wt) and a cisplatin-resistant sub-line (P31 res). The aim was to first characterize K+ fluxes in P31 wt and P31 res cells, and then manipulate them in order to reduce intracellular K+ and induce apoptosis with K+ manipulation alone or in combination with cisplatin. Characterization of K+ fluxes in P31 wt cells showed that: 1) ouabain, a digitalis-like drug, and specific blocker of the Na+, K+, ATPase pump, effectively inhibited K+ uptake, 2) bumetanide, a diuretic, and an inhibitor of the Na+, K+, 2Cl-¬-cotransporter, had a transient effect on K+ uptake, and 3) the antifungal drug amphotericin B stimulated K+ efflux. In order to determine intracellular K+ content, the potassium-binding fluorescent probe PBFI-AM was used in a 96-well plate assay. After a 3-h incubation with ouabain, with or without bumetanide, combined with amphotericin B, the intracellular K+ content was reduced in P31 wt cells but not in P31 res cells. Ouabain induced apoptosis in both P31 wt and P31 res cells. P31 res cells were sensitized to cisplatin by ouabain, since 10 mg/L cisplatin in combination with ouabain induced about the same percentage of apoptotic cells as 40 mg/L cisplatin. Apoptosis was executed via caspase-3 activation in both P31 wt and P31 res cells. Amphotericin B enhanced ouabain-induced apoptosis in P31 wt cells via caspase-9 activation, with increased caspase-3 activation and DNA fragmentation as consequences. Ouabain-induced apoptosis in P31 res cells was executed via increased expression of pro-apoptotic Bak. The combination of cisplatin with ouabain and amphotericin B was stressful to both P31 wt and P31 res cells, since SAPK/JNK a known factor in stress-induced apoptosis was activated. In conclusion, K+ flux manipulation with clinical used drugs can induce apoptosis per se and also enhance cisplatin-induced apoptosis in P31 wt and P31 res cells.
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- Brattström, Daniel, 1966-
(författare)
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Angiogenesis Related Markers In Non-Small Cell Lung Cancer
- 2003
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis investigated the predictive and the prognostic powers of angiogenesis related markers in both operable and inoperable non-small cell lung cancer (NSCLC) patients.In the first and second study, we investigated the serological fractions of vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) in 2 cohorts of patients with either operable or inoperable NSCLC. Regarding operable NSCLC, we demonstrated significant correlations between VEGF and tumour volume and overall survival. Regarding bFGF, significant correlations with recurrent disease and survival were demonstrated. VEGF and bFGF correlated to each other and with platelet counts. In multivariate analysis, bFGF proved to be a significantly independent prognostic factor.Regarding inoperable NSCLC, we demonstrated that patients with elevated bFGF levels before any treatment and during chemotherapy had a significantly poorer survival. During chemotherapy, each rise of one unit of bFGF (ng/L) corresponded to a 4 times increased risk of death. Regarding VEGF, elevated levels after radiotherapy corresponded with better survival. All prognostic information demonstrated in this study concerned patients with a, co-sampled, normal platelet count.In the third study, three putative markers, HER-2, EGFR and COX-2, suitable for targeted therapies in resected NSCLC were investigated in a panel of 53 tumours and further investigated for a possible correlation with microvessel density. We demonstrated that HER-2 and COX-2 were mainly expressed in adenocarcinomas, whereas EGFR was only expressed in squamous cell carcinomas. COX-2 showed a trend towards a correlation with microvesssel density. The expression profile, HER-2+/EGFR-, was significantly correlated to poorer survival. In the fourth study, a predictive model for recurrences consisting of p53, CD34 and CD105, and circulating serum fractions of VEGF and bFGF, was investigated. The two endothelial markers correlated with each other. CD105 expression correlated with p53 expression. No other significant correlations between markers could be demonstrated. A significant correlation between p53 overexpression and recurrent disease was demonstrated. The mutational status could not confirm the immunohistochemical correlation between p53 and recurrences. In conclusion, the present thesis demonstrates that the angiogenic factors VEGF and bFGF analysed in sera have both predictive and prognostic information when measured in operable and inoperable NSCLC. Since HER-2 is overexpressed in NSCLC and linked with prognostic information, this marker might be a suitable target for therapy in NSCLC. Furthermore, in patients with operable NSCLC, p53 expression status was linked with recurrent disease and mean MVD.
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| 7. |
- Brattström, Daniel, et al.
(författare)
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Serum VEGF and bFGF adds prognostic information in patients with normal platelet counts when sampled before, during and after treatment for locally advanced non-small cell lung cancer
- 2003
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Ingår i: Lung Cancer. - : Elsevier BV. - 0169-5002 .- 1872-8332. ; 43:1, s. 55-62
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Tidskriftsartikel (refereegranskat)abstract
- Vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) have both been implicated to have roles in tumour angiogenesis. In the present retrospective study, serum VEGF and bFGF from patients with locally advanced non-small cell lung cancer (NSCLC) were analysed before, during and after treatment. Seventy-three patients and a total of 460 serum samples were analysed for VEGF and 443 serum samples were analysed for bFGF. Pre-treatment bFGF levels in patients with normal platelet counts, were correlated to poorer survival, P-value = 0.047. During chemotherapy, each rise of one unit bFGF corresponded to a hazard ratio of 4.06 (P=0.022). In patients with normal platelet counts, VEGF levels after radiotherapy significantly correlated to good prognosis (P=0.023), during radiotherapy VEGF levels indicated the same correlation (P=0.085). We conclude that serum VEGF and especially bFGF are of clinical interest as prognostic factors, especially in patients presenting with normal platelet counts.
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| 8. |
- Brodin, Daniel, et al.
(författare)
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Inhaled ciclesonide in adults hospitalised with COVID-19 : a randomised controlled open-label trial (HALT COVID-19)
- 2023
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Ingår i: BMJ Open. - : BMJ Publishing Group Ltd. - 2044-6055. ; 13:2
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: To assess the efficacy of inhaled ciclesonide in reducing the duration of oxygen therapy (an indicator of time to clinical improvement) among adults hospitalised with COVID-19.DESIGN: Multicentre, randomised, controlled, open-label trial.SETTING: 9 hospitals (3 academic hospitals and 6 non-academic hospitals) in Sweden between 1 June 2020 and 17 May 2021.PARTICIPANTS: Adults hospitalised with COVID-19 and receiving oxygen therapy.INTERVENTION: Inhaled ciclesonide 320 µg two times a day for 14 days versus standard care.MAIN OUTCOME MEASURES: Primary outcome was duration of oxygen therapy, an indicator of time to clinical improvement. Key secondary outcome was a composite of invasive mechanical ventilation/death.RESULTS: Data from 98 participants were analysed (48 receiving ciclesonide and 50 receiving standard care; median (IQR) age, 59.5 (49-67) years; 67 (68%) men). Median (IQR) duration of oxygen therapy was 5.5 (3-9) days in the ciclesonide group and 4 (2-7) days in the standard care group (HR for termination of oxygen therapy 0.73 (95% CI 0.47 to 1.11), with the upper 95% CI being compatible with a 10% relative reduction in oxygen therapy duration, corresponding to a <1 day absolute reduction in a post-hoc calculation). Three participants in each group died/received invasive mechanical ventilation (HR 0.90 (95% CI 0.15 to 5.32)). The trial was discontinued early due to slow enrolment.CONCLUSIONS: In patients hospitalised with COVID-19 receiving oxygen therapy, this trial ruled out, with 0.95 confidence, a treatment effect of ciclesonide corresponding to more than a 1 day reduction in duration of oxygen therapy. Ciclesonide is unlikely to improve this outcome meaningfully.TRIAL REGISTRATION NUMBER: NCT04381364.
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