142 results on '"Björnstedt M"'
Search Results
2. Mid-Infrared Imaging Is Able to Characterize and Separate Cancer Cell Lines
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Kontsek, E., Pesti, A., Björnstedt, M., Üveges, T., Szabó, E., Garay, T., Gordon, P., Gergely, S., and Kiss, A.
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- 2020
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3. Relatively high mortality risk in elderly Swedish subjects with low selenium status
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Alehagen, U, Johansson, P, Björnstedt, M, Rosén, A, Post, C, and Aaseth, J
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- 2016
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4. Nitric oxide and endothelin-1 release after one-lung ventilation during thoracoabdominal esophagectomy
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Lund, M., Ny, L., Malmström, R. E., Lundberg, J. O., Öst, Å., Björnstedt, M., Lundell, L., and Tsai, J. A.
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- 2013
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5. Can laboratory x-ray virtual histography provide intraoperative 3D tumor resection margin assessment?
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Müller, Bert, Wang, Ge, Twengström, W., Fernandez Moro, C., Romell, J., Larsson, J. C., Sparrelid, E., Björnstedt, M., and Hertz, H. M.
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- 2021
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6. Hepatic ischemia-reperfusion injury induced by portal triad clamping: morphometric analysis of electron microscopic findings
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D'souza, M.A., primary, Jawad, R., additional, Wallenberg, M., additional, Arodin Selenius, L., additional, Nowak, G., additional, Björnstedt, M., additional, and Isaksson, B., additional
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- 2016
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7. Immunoelectron microscopy reveals alteration in thioredoxin/glutaredoxin activity in hepatic ischemia-reperfusion induced by portal triad clamping
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D'souza, M., primary, Arodin Selenius, L., additional, Jawad, R., additional, Wallenberg, M., additional, Danielsson, O., additional, Nowak, G., additional, Björnstedt, M., additional, and Isaksson, B., additional
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- 2016
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8. Relatively high mortality risk in elderly Swedish subjects with low selenium status
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Alehagen, U, primary, Johansson, P, additional, Björnstedt, M, additional, Rosén, A, additional, Post, C, additional, and Aaseth, J, additional
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- 2015
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9. Increased expression of specific thioredoxin family proteins; a pilot immunohistochemical study on human hepatocellular carcinoma
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Cunnea, P., Fernandes, AP, Capitanio, A., Eken, S., Spyrou, Giannis, Björnstedt, M., Cunnea, P., Fernandes, AP, Capitanio, A., Eken, S., Spyrou, Giannis, and Björnstedt, M.
- Abstract
Hepatocellular Carcinoma (HCC) is one of the most frequent cancers worldwide, however, prognosis remains poor following its discovery. We investigate the Thioredoxin superfamily of proteins as diagnostic markers for HCC. Furthermore, we delineate possible roles of the endoplasmic reticulum member of the superfamily, ERdj5, in carcinogenesis. Using antibodies against Thioredoxin 1, Thioredoxin Reductase 1 and ERdj5, we performed immunohistochemistry on paraffin embedded liver biopsy sections from HCC patients. All three redox proteins exhibited elevated expression levels in tumor tissue compared to internal control, with ERdj5 showing a remarkable 3-fold increase. In vitro cell viability experiments using Hepatocellular Carcinoma HuH7 cells treated with ERdj5 small interfering RNA showed that ERdj5 knockdown cells exhibited less resistance to Doxorubicin (chemotherapy drug), but more resistance to Tunicamycin (Endoplasmic Stress inducer), compared to control cells. In conclusion, we introduce members of the Thioredoxin superfamily as possible immunohistochemical markers in the diagnostics of hepatocellular carcinoma and indicate a potential defensive role for ERdj5 in chemotherapeutic drug resistance.
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- 2007
10. Adriamycin cytotoxicity may stimulate growth of hepatocellular tumours in an experimental model for adjuvant systemic chemotherapy in liver transplantation
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Rissler, P., Söderdahl, G., Nordman, Tomas, Xia, L., Torndal, U. -B, Björnstedt, M., Ericzon, B. -G, Olsson, J. M., Eriksson, L. C., Rissler, P., Söderdahl, G., Nordman, Tomas, Xia, L., Torndal, U. -B, Björnstedt, M., Ericzon, B. -G, Olsson, J. M., and Eriksson, L. C.
- Abstract
Adjuvant treatment with adriamycin has been suggested to improve results after liver transplantation for hepatocellular cancer. Here we have applied an animal model for evaluation of treatment with adriamycin and/or cyclosporine A on liver tumour growth. Three chemically induced rat liver tumours with various degree of differentiation were transferred to the spleens of syngenic rats. Each recipient group was divided into four subgroups, treated with adriamycin and/or cyclosporine A or none of the drugs. When the tumour was well differentiated no proliferation was found in any of the subgroups. When the tumour exhibited a more pronounced dysplasia, adriamycin stimulated tumour growth. This effect was further increased by cyclosporine. In the animals transplanted with the most aggressive tumour, adriamycin inhibited tumour growth. When given together with cyclosporine this inhibition was counteracted. These data suggest that adriamycin, especially when given together with cyclosporine, may have a stimulatory effect on liver tumour cell growth.
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- 2005
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11. Role of selenite in differentiation of acute myeloid leukemia cells
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Misra⁎, S., primary, Wallenberg, M., additional, Barsham, A., additional, Björnstedt, M., additional, and Fernandes, A., additional
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- 2012
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12. Redox proteins in the defense against dopamine induced cell death
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Arodin, L., primary, Nennesmo, I., additional, Björnstedt, M., additional, and Fernandes⁎, A.P., additional
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- 2012
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13. Nitric oxide and endothelin-1 release after one-lung ventilation during thoracoabdominal esophagectomy
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Lund, M., primary, Ny, L., additional, Malmström, R. E., additional, Lundberg, J. O., additional, Öst, Å., additional, Björnstedt, M., additional, Lundell, L., additional, and Tsai, J. A., additional
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- 2012
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14. Reduction of ubiquinone by lipoamide dehydrogenase : An antioxidant regenerating pathway
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Xia, Ling, Björnstedt, M., Nordman, Tomas, Eriksson, L. C., Olsson, J. M., Xia, Ling, Björnstedt, M., Nordman, Tomas, Eriksson, L. C., and Olsson, J. M.
- Abstract
Lipoamide dehydrogenase belongs to a family of pyridine nucleotide disulfide oxidoreductases and is ubiquitous in aerobic organisms. This enzyme also reduces ubiquinone (the only endogenously synthesized lipid-soluble antioxidant) to ubiquinol, the form in which it functions as an antioxidant. The reduction of ubiquinone was linear with time and exhibited turnover numbers of 5 and 1.2 min-1 in the presence and absence of zinc, respectively. The reaction was stimulated by zinc and cadmium but not by the other divalent ions tested. The zinc/cadmium-dependent stimulation of the reaction increased rapidly and linearly up to a concentration of 0.1 mM and was even further increased at 0.5 mM. At pH 6, the activity was three times higher than at physiological pH. Alteration of the NADPH : NADP+ ratio revealed that the reaction is inhibited by higher concentrations of the oxidized cofactors. FAD reduced ubiquinone in a dose-dependent manner at a considerably lower rate, suggesting that the reduction of ubiquinone by lipoamide dehydrogenase involves the FAD moiety of the enzyme.
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- 2001
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15. 6537 POSTER Selenite mediated cytotoxcicity in human lung cancer and the role of Thioredoxin reductase 1
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Fernandes, A.P., primary, Selenius, M., additional, Capitanio, A., additional, Brodin, O., additional, Björnstedt, M., additional, and Rundlöf, A.K., additional
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- 2007
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16. 6008 POSTER Selenite is a superior cytotoxic agent to human primary leukemia cells
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Olm, E., primary, Jönsson-Videsäter, K., additional, Rundlöf, A.K., additional, Fernandes, A.P., additional, Ribera, I., additional, Eriksson, L., additional, Paul, C., additional, and Björnstedt, M., additional
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- 2007
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17. Increased Expression of Specific Thioredoxin Family Proteins; A Pilot Immunohistochemical Study on Human Hepatocellular Carcinoma
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Cunnea, P., primary, Fernandes, A.P., additional, Capitanio, A., additional, Eken, S., additional, Spyrou, G., additional, and Björnstedt, M., additional
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- 2007
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18. 215 Targeting thioredoxin reductase ‐ a possible new treatment for malignant mesothelioma
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Nilsonne, G., primary, Stein, A., additional, Rundlöf, A.-K., additional, Fernandes, A.P., additional, Björnstedt, M., additional, Hjerpe, A., additional, and Dobra, K., additional
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- 2006
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19. Selenium and the thioredoxin and glutaredoxin systems
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Björnstedt, M., Kumar, S., Björkhem, L., Spyrou, Giannis, Holmgren, A., Björnstedt, M., Kumar, S., Björkhem, L., Spyrou, Giannis, and Holmgren, A.
- Abstract
Thioredoxin (Trx) is a small ubiquitous dithiol protein which together with the FAD-containing enzyme thioredoxin reductase (TR) and NADPH (the Trx system) is a hydrogen donor for ribonucleotide reductase essential for DNA synthesis and a general protein disulfide reductase involved in redox regulation. Selenite, selenodiglutathione (GS-Se-SG) and selenocystine are efficiently reduced by thioredoxins and also directly by NADPH and mammalian TR but not by the E. coli enzyme. Incubation of selenite or GS-Se-SG with the Trx system or with mammalian TR results in a rapid formation of selenide, which by redox cycling with oxygen may cause a large non-stoichiometric oxidation of NADPH. Selenocystine is efficiently reduced into two molecules of the selenol amino acid selenocysteine by mammalian TR with a K(m)-value (6 mumol.L-1) and a high turnover number (kappa cat 3200 min-1) almost identical to the natural substrate Trx-S2. TR also directly reduces lipid hydroperoxides and this peroxidase reaction is strongly stimulated by the presence of catalytic amounts of free selenocysteine. Glutaredoxin (Grx) which catalyzes GSH-dependent disulfide reduction also via a redox-active disulfide and Trx are both efficient electron donors to the human plasma glutathione peroxidase providing a mechanism by which human plasma glutathione peroxidase may reduce hydroperoxides in an environment almost free from glutathione. Selenate is reduced by Grx and Trx in the presence of GSH. The DNA-binding of the transcription factor AP-1 is strongly inhibited by GS-Se-SG and selenite. Furthermore, selenide formed by TR-mediated reduction of selenite and GS-Se-SG inhibits lipoxygenase and changes the electron spin resonance spectrum of the active site iron. Mammalian TR with two subunits of 57 kDa has recently been cloned and shown to be homologous to glutathione reductase. The rat enzyme contains a selenocysteine residue in a unique Cterminal position and a conserved SECIS sequence directing insert
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- 1997
20. Selenite and selenate inhibit human lymphocyte growth via different mechanisms
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Spyrou, Giannis, Björnstedt, M., Skog, S., Holmgren, A., Spyrou, Giannis, Björnstedt, M., Skog, S., and Holmgren, A.
- Abstract
Selenium compounds like selenite and selenate have strong inhibitory effects, particularly on mammalian tumor cell growth by unknown mechanisms. We found that the addition of sodium selenite and sodium selenate inhibited the growth of human 3B6 and BL41 lymphocytes. Selenite was more potent because 10 microM selenite produced a growth inhibitory effect similar to that of 250 microM selenate. The mechanism of action of selenite and selenate appears to be different. 3B6 and BL41 cells treated with selenite accumulated in the S-phase; however, selenate caused an accumulation of cells in G2. Selenite-mediated growth inhibition was irreversible, although the effects of selenate could be reversed. Selenite, in contrast to selenate, is efficiently reduced by the thioredoxin system (thioredoxin, thioredoxin reductase, and NADPH). At concentrations required to observe a similar effect on cell growth, the activity of thioredoxin reductase, recently shown to be a selenoprotein, increased in selenite-treated cells and decreased in selenate-treated cells. Ribonucleotide reductase activity was inhibited in an in vitro assay by selenite and selenodiglutathione but not by selenate. These results show that selenite and selenate use different mechanisms to inhibit cell growth.
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- 1996
21. AP-1 DNA-binding activity is inhibited by selenite and selenodiglutathione
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Spyrou, Giannis, Björnstedt, M., Kumar, S., Holmgren, A., Spyrou, Giannis, Björnstedt, M., Kumar, S., and Holmgren, A.
- Abstract
The binding of the transcription factor AP-1 to DNA has been shown to be modulated by redox control mechanisms. Selenite and selenodiglutathione (GS-Se-SG), inhibit mammalian cell growth and are efficient oxidants of reduced thioredoxin and reduced thioredoxin reductase. Here, we report that selenite and GS-Se-SG efficiently inhibited AP-1 DNA-binding in nuclear extracts from 3B6 lymphocytes. A GS-Se-SG concentration of 0.75 microM resulted in 50% inhibition of AP-1 DNA-binding, whereas the same effect was achieved with 7.5 microM selenite. Nuclear extracts prepared from human 3B6 lymphocytes exposed for 4 h to 10 microM selenite showed a 50% reduction of AP-1 binding. These data suggest that selenite and selenodiglutathione inactivate the AP-1 factor and provide a mechanism by which selenium compounds inhibit cell growth.
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- 1995
22. Upregulation of 9 genes, including that for thioredoxin, during epithelial differentiation of mesothelioma cells
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Sun, X., primary, Dobra, K., additional, Björnstedt, M., additional, and Hjerpe, A., additional
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- 2000
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23. The thioredoxin and glutaredoxin systems are efficient electron donors to human plasma glutathione peroxidase.
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Björnstedt, M, primary, Xue, J, additional, Huang, W, additional, Akesson, B, additional, and Holmgren, A, additional
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- 1994
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24. Selenodiglutathione is a highly efficient oxidant of reduced thioredoxin and a substrate for mammalian thioredoxin reductase.
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Björnstedt, M, primary, Kumar, S, additional, and Holmgren, A, additional
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- 1992
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25. Can laboratory x-ray virtual histography provide intraoperative 3D tumor resection margin assessment?
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Twengström, W., Fernandez Moro, C., Romell, J., Larsson, J. C., Sparrelid, E., Björnstedt, M., and Hertz, H. M.
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- 2021
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26. Human thioredoxin reductase directly reduces lipid hydroperoxides by NADPH and selenocystine strongly stimulates the reaction via catalytically generated selenols.
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Björnstedt, M, Hamberg, M, Kumar, S, Xue, J, and Holmgren, A
- Abstract
Human placenta thioredoxin reductase (HP-TR) in the presence of NADPH-catalyzed reduction of (15S)-hydroperoxy-(5Z),(8Z),11(Z),13(E)-eicosatetraenoic acid ((15S)-HPETE) into the corresponding alcohol ((15S)-HETE). Incubation of 50 nM HP-TR and 0.5 mM NADPH with 300 microM 15-HPETE for 5 min resulted in formation of 16.5 microM 15-HETE. After 60 min, 74.7 microM 15-HPETE was reduced. The rate of the reduction of 15-HPETE by the HP-TR/NADPH peroxidase system was increased 8-fold by the presence of 2.5 microM selenocystine, a diselenide amino acid. In this case, 15-HPETE was catalytically reduced by the selenol amino acid, selenocysteine, generated from the diselenide by the HP-TR/NADPH system. To a smaller extent, selenodiglutathione or human thioredoxin also potentiated the reduction of 15-HPETE by HP-TR. Hydrogen peroxide and 15-HPETE were reduced at approximately the same rate by HP-TR, thioredoxin, and selenocystine. In contrast, t-butyl hydroperoxide was reduced at a 10-fold lower rate. Our data suggest two novel pathways for the reduction and detoxification of lipid hydroperoxides, hydrogen peroxide, and organic hydroperoxides, i.e. the human thioredoxin reductase-dependent pathway and a coupled reduction in the presence of selenols or selenide resulting from the reduction of selenocystine or selenodiglutathione.
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- 1995
27. 1-Chloro-2,4-dinitrobenzene is an irreversible inhibitor of human thioredoxin reductase. Loss of thioredoxin disulfide reductase activity is accompanied by a large increase in NADPH oxidase activity.
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Arnér, E S, Björnstedt, M, and Holmgren, A
- Abstract
Human thioredoxin reductase is a dimeric enzyme that catalyzes reduction of the disulfide in oxidized thioredoxin by a mechanism involving transfer of electrons from NADPH via FAD to a redox-active disulfide. 1-Chloro-2,4-dinitrobenzene (DNCB) is an alkylating agent used for depleting intracellular GSH and also showing distinct immunomodulatory properties. We have discovered that low concentrations of DNCB completely inactivated human or bovine thioredoxin reductase, with a second order rate constant in excess of 200 M-1 s-1, which is almost 10,000-fold faster than alkylation of GSH. Total inactivation of 50 nM reduced thioredoxin reductase was obtained by 100 microM DNCB after 5 reductase was obtained by 100 microM DNCB after 5 min of incubation at 20 degrees C also in the presence of 1 mM GSH. The inhibition occurred with enzyme only in the presence of NADPH and persisted after removal of DNCB, suggesting alkylation of the active site nascent thiols as the mechanism of inactivation. Thioredoxin reductase modified by DNCB lacked reducing activity with oxidized thioredoxin, 5,5'-dithiobis-(2-nitrobenzoic acid), or sodium selenite. However, the DNCB-modified enzyme oxidized NADPH at a rate of 4.7 nmol/min/nmol of enzyme in the presence of atmospheric oxygen. This activity was not dependent on the presence of DNCB in solution and constituted a 34-fold increase of the inherent low NADPH oxidase activity of the native enzyme. DNCB is a specific inhibitor of mammalian thioredoxin reductase, which reacted 100-fold faster than glutathione reductase. The inactivation of the disulfide reducing activity of thioredoxin reductase and thioredoxin with a concomitant large increase of the NADPH oxidase activity producing reactive oxygen intermediates may mediate effects of DNCB on cells in vivo.
- Published
- 1995
28. Phenotype-dependent apoptosis signalling in mesothelioma cells after selenite exposure
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Rundlöf Anna-Klara, Kocic Branka, Stein Agnes, Mundt Filip, Szulkin Adam, Olm Eric, Nilsonne Gustav, Fernandes Aristi P, Björnstedt Mikael, and Dobra Katalin
- Subjects
Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Abstract Background Selenite is a promising anticancer agent which has been shown to induce apoptosis in malignant mesothelioma cells in a phenotype-dependent manner, where cells of the chemoresistant sarcomatoid phenotype are more sensitive. Methods In this paper, we investigate the apoptosis signalling mechanisms in sarcomatoid and epithelioid mesothelioma cells after selenite treatment. Apoptosis was measured with the Annexin-PI assay. The mitochondrial membrane potential, the expression of Bax, Bcl-XL, and the activation of caspase-3 were assayed with flow cytometry and a cytokeratin 18 cleavage assay. Signalling through JNK, p38, p53, and cathepsins B, D, and E was investigated with chemical inhibitors. Furthermore, the expression, nuclear translocation and DNA-binding activity of p53 was investigated using ICC, EMSA and the monitoring of p21 expression as a downstream event. Levels of thioredoxin (Trx) were measured by ELISA. Results In both cell lines, 10 μM selenite caused apoptosis and a marked loss of mitochondrial membrane potential. Bax was up-regulated only in the sarcomatoid cell line, while the epithelioid cell line down-regulated Bcl-XL and showed greater caspase-3 activation. Nuclear translocation of p53 was seen in both cell lines, but very little p21 expression was induced. Chemical inhibition of p53 did not protect the cells from apoptosis. p53 lost its DNA binding ability after selenite treatment and was enriched in an inactive form. Levels of thioredoxin decreased after selenite treatment. Chemical inhibition of MAP kinases and cathepsins showed that p38 and cathepsin B had some mediatory effect while JNK had an anti-apoptotic role. Conclusion We delineate pathways of apoptosis signalling in response to selenite, showing differences between epithelioid and sarcomatoid mesothelioma cells. These differences may partly explain why sarcomatoid cells are more sensitive to selenite.
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- 2009
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29. Exploring Selenoprotein P in Liver Cancer: Advanced Statistical Analysis and Machine Learning Approaches.
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Razaghi A and Björnstedt M
- Abstract
Selenoprotein P (SELENOP) acts as a crucial mediator, distributing selenium from the liver to other tissues within the body. Despite its established role in selenium metabolism, the specific functions of SELENOP in the development of liver cancer remain enigmatic. This study aims to unravel SELENOP's associations in hepatocellular carcinoma (HCC) by scrutinizing its expression in correlation with disease characteristics and investigating links to hormonal and lipid/triglyceride metabolism biomarkers as well as its potential as a prognosticator for overall survival and predictor of hypoxia. SELENOP mRNA expression was analyzed in 372 HCC patients sourced from The Cancer Genome Atlas (TCGA), utilizing statistical methodologies in R programming and machine learning techniques in Python. SELENOP expression significantly varied across HCC grades ( p < 0.000001) and among racial groups ( p = 0.0246), with lower levels in higher grades and Asian individuals, respectively. Gender significantly influenced SELENOP expression ( p < 0.000001), with females showing lower altered expression compared to males. Notably, the Spearman correlation revealed strong positive connections of SELENOP with hormonal markers (AR, ESR1, THRB) and key lipid/triglyceride metabolism markers (PPARA, APOC3, APOA5). Regarding prognosis, SELENOP showed a significant association with overall survival ( p = 0.0142) but explained only a limited proportion of variability (~10%). Machine learning suggested its potential as a predictive biomarker for hypoxia, explaining approximately 18.89% of the variance in hypoxia scores. Future directions include validating SELENOP's prognostic and diagnostic value in serum for personalized HCC treatment. Large-scale prospective studies correlating serum SELENOP levels with patient outcomes are essential, along with integrating them with clinical parameters for enhanced prognostic accuracy and tailored therapeutic strategies.
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- 2024
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30. Combining PD-1/PD-L1 blockade with type I interferon in cancer therapy.
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Razaghi A, Durand-Dubief M, Brusselaers N, and Björnstedt M
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- Humans, Programmed Cell Death 1 Receptor, B7-H1 Antigen, Interferon-alpha, Immune Checkpoint Inhibitors adverse effects, Interferon Type I therapeutic use, Melanoma
- Abstract
PD-1 and PD-L1 are crucial regulators of immunity expressed on the surface of T cells and tumour cells, respectively. Cancer cells frequently use PD-1/PD-L1 to evade immune detection; hence, blocking them exposes tumours to be attacked by activated T cells. The synergy of PD-1/PD-L1 blockade with type I interferon (IFN) can improve cancer treatment efficacy. Type I IFN activates immune cells boosts antigen presentation and controls proliferation. In addition, type I IFN increases tumour cell sensitivity to the blockade. Combining the two therapies increases tumoral T cell infiltration and activation within tumours, and stimulate the generation of memory T cells, leading to prolonged patient survival. However, limitations include heterogeneous responses, the need for biomarkers to predict and monitor outcomes, and adverse effects and toxicity. Although treatment resistance remains an obstacle, the combined therapeutic efficacy of IFNα/β and PD-1/PD-L1 blockade demonstrated considerable benefits across a spectrum of cancer types, notably in melanoma. Overall, the phases I and II clinical trials have demonstrated safety and efficiency. In future, further investigations in clinical trials phases III and IV are essential to compare this combinatorial treatment with standard treatment and assess long-term side effects in patients., Competing Interests: The authors have no conflict of interest. The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Razaghi, Durand-Dubief, Brusselaers and Björnstedt.)
- Published
- 2023
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31. FPR2 Shapes an Immune-Excluded Pancreatic Tumor Microenvironment and Drives T-cell Exhaustion in a Sex-Dependent Manner.
- Author
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He F, Tay AHM, Calandigary A, Malki E, Suzuki S, Liu T, Wang Q, Fernández-Moro C, Kaisso M, Olofsson-Sahl P, Melssen M, Sze SK, Björnstedt M, Löhr MJ, Karlsson MCI, Heuchel R, and Sarhan D
- Subjects
- Mice, Male, Female, Animals, Proteomics, T-Cell Exhaustion, Myeloid Cells, Mice, Knockout, Tumor Microenvironment, Pancreatic Neoplasms genetics
- Abstract
Sex-driven immune differences can affect tumor progression and the landscape of the tumor microenvironment. Deeper understanding of these differences in males and females can inform patient selection to improve sex-optimized immunotherapy treatments. In this study, single-cell RNA sequencing and protein analyses uncovered a subpopulation of myeloid cells in pancreatic lesions associated with an immune-excluded tumor phenotype and effector T-cell exhaustion exclusively in females. This myeloid subpopulation was positively correlated with poor survival and genetic signatures of M2-like macrophages and T-cell exhaustion in females. The G-protein coupled receptor formyl peptide receptor 2 (FPR2) mediated these immunosuppressive effects. In vitro, treatment of myeloid cells with a specific FPR2 antagonist prevented exhaustion and enhanced cytotoxicity of effector cells. Proteomic analysis revealed high expression of immunosuppressive secretory proteins PGE2 and galectin-9, enriched integrin pathway, and reduced proinflammatory signals like TNFα and IFNγ in female M2-like macrophages upon FPR2 agonist treatment. In addition, myeloid cells treated with FPR2 agonists induced TIM3 and PD-1 expression only in female T cells. Treatment with anti-TIM3 antibodies reversed T-cell exhaustion and stimulated their ability to infiltrate and kill pancreatic spheroids. In vivo, progression of syngeneic pancreatic tumors was significantly suppressed in FPR2 knockout (KO) female mice compared with wild-type (WT) female mice and to WT and FPR2 KO male mice. In female mice, inoculation of tumors with FPR2 KO macrophages significantly reduced tumor growth compared with WT macrophages. Overall, this study identified an immunosuppressive function of FPR2 in females, highlighting a potential sex-specific precision immunotherapy strategy., Significance: FPR2 is a sex-dependent mediator of macrophage function in pancreatic cancer and can be targeted to reprogram macrophages and stimulate antitumor immunity in females., (©2023 American Association for Cancer Research.)
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- 2023
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32. Fibrosis-Related Gene Profiling in Liver Biopsies of PiZZ α1-Antitrypsin Children with Different Clinical Courses.
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Kamp JC, Kappe NN, Moro CF, Fuge J, Kuehnel MP, Wrenger S, Welte T, Hoek BV, Jonigk DD, Khedoe PPSJ, Strnad P, Björnstedt M, Stolk J, Janciauskiene S, and Nemeth A
- Subjects
- Humans, Child, Infant, Newborn, Liver metabolism, Liver Cirrhosis genetics, Liver Cirrhosis pathology, Biopsy, Disease Progression, Lipids, alpha 1-Antitrypsin Deficiency pathology, Cholestasis metabolism
- Abstract
PiZZ (Glu342Lys) α1-antitrypsin deficiency (AATD) is characterized by intrahepatic AAT polymerization and is a risk factor for liver disease development in children. The majority of PiZZ children are disease free, hence this mutation alone is not sufficient to cause the disease. We investigated Z-AAT polymers and the expression of fibrosis-related genes in liver tissues of PiZZ children with different clinical courses. Liver biopsies obtained during 1979-2010 at the Department of Paediatrics, Karolinska University Hospital, Sweden, were subjected to histological re-evaluation, immunohistochemistry and NanoString-based transcriptome profiling using a panel of 760 fibrosis plus 8 bile acid-related genes. Subjects were divided into three groups based on clinical outcomes: NCH (neonatal cholestasis, favourable outcome, n = 5), NCC (neonatal cholestasis, early cirrhosis and liver transplantation, n = 4), and NNCH (no neonatal cholestasis, favourable outcome, n = 5, six biopsies). Hepatocytes containing Z-AAT polymers were abundant in all groups whereas NCC showed higher expression of genes related to liver fibrosis/cirrhosis and lower expression of genes related to lipid, aldehyde/ketone, and bile acid metabolism. Z-AAT accumulation per se cannot explain the clinical outcomes of PiZZ children; however, changes in the expression of specific genes and pathways involved in lipid, fatty acid, and steroid metabolism appear to reflect the degree of liver injury.
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- 2023
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33. Intravenous Infusion of High Dose Selenite in End-Stage Cancer Patients: Analysis of Systemic Exposure to Selenite and Seleno-Metabolites.
- Author
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Breuer O, Brodin O, Razaghi A, Brodin D, Gammelgaard B, and Björnstedt M
- Abstract
Cancer is one of the main causes of human death globally and novel chemotherapeutics are desperately required. As a simple selenium oxide, selenite is a very promising chemotherapeutic because of pronounced its dose-dependent tumor-specific cytotoxicity. We previously published a first-in-man systematic phase I clinical trial in patients with cancer (from IV to end-stage) (the SECAR trial) showing that selenite is safe and tolerable with an unexpectable high maximum tolerated dose (MTD) and short half-life. In the present study, we analyzed the selenium species in plasma samples, from the patients participating in the SECAR trial and from various time points and dose cohorts using LC-ICP-MS. In conclusion, selenite, selenosugars, and 1-2 unidentified peaks that did not correspond to any standard, herein denoted ui-selenium, were detected in the plasma. However, trimethylated selenium (trimethylselenonoium) was not detected. The unidentified ui-selenium was eluting close to the selenium-containing amino acids (selenomethionine and selenocysteine) but was not part of a protein fraction. Our data demonstrate that the major metabolite detected was selenosugar. Furthermore, the identification of selenite even long after the administration is remarkable and unexpected. The kinetic analysis did not support that dosing per the body surface area would reduce interindividual variability of the systemic exposure in terms of trough concentrations.
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- 2023
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34. Exploration of Patient-Derived Pancreatic Ductal Adenocarcinoma Ex Vivo Tissue for Treatment Response.
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Szekerczés T, Selvam AK, Moro CF, Elduayen SP, Dillner J, Björnstedt M, and Ghaderi M
- Abstract
Patient-derived tissue culture models are valuable tools to investigate drug effects and targeted treatment approaches. Resected tumor slices cultured ex vivo have recently gained interest in precision medicine, since they reflect the complex microenvironment of cancer tissue. In this study, we examined the treatment response to an internally developed ex vivo tissue culture model from pancreatic ductal adenocarcinoma (PDAC) and in vitro analysis. Seven PDAC tissues were cultured and subsequently treated with indole-3-pyruvic acid (IPA). IPA, which is known as an agonist of the aryl hydrocarbon receptor (AHR) pathway, has antioxidant properties. Genome-wide transcriptome sequencing analysis revealed activation of AHR pathway genes (CYP1A1 and CYP1B1, p ≤ 0.05). Additionally, significant upregulation of AHR repressor genes AHRR and TiPARP was also observed ( p ≤ 0.05), which is indicative of the negative feedback loop activation of AHR pathway signaling. The overall transcriptomic response to IPA indicated that the tissues are biologically active and respond accordingly to exogenous treatment. Cell culture analysis confirmed the significant induction of selected AHR genes by IPA. A morphological examination of the paraffin-embedded formalin-fixed tissue did not show obvious signs of IPA treatment related to tumor cell damage. This study is a proof of concept that ex vivo patient-derived tissue models offer a valuable tool in precision medicine to monitor the effect of personalized treatments.
- Published
- 2023
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35. Morphological changes without histological myocarditis in hearts of COVID-19 deceased patients.
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Razaghi A, Szakos A, Al-Shakarji R, Björnstedt M, and Szekely L
- Subjects
- Heart, Humans, Necrosis complications, SARS-CoV-2, COVID-19, Myocarditis complications, Myocarditis pathology
- Abstract
Objective. Patients with underlying heart diseases have a higher risk of dying from Covid-19. It has also been suggested that Covid-19 affects the heart through myocarditis. Despite the rapidly growing research on the management of Covid-19 associated complications, most of the ongoing research is focused on the respiratory complications of Covid-19, and little is known about the prevalence of myocarditis. Design. This study aimed to characterize myocardial involvement by using a panel of antibodies to detect hypoxic and inflammatory changes and the presence of SARS-CoV-2 proteins in heart tissues obtained during the autopsy procedure of Covid-19 deceased patients. Thirty-seven fatal COVID-19 cases and 21 controls were included in this study. Results. Overall, the Covid-19 hearts had several histopathological changes like the waviness of myocytes, fibrosis, contract band necrosis, infiltration of polymorphonuclear neutrophils, vacuolization, and necrosis of myocytes. In addition, endothelial damage and activation were detected in heart tissue. However, viral replication was not detected using RNA in situ hybridization. Also, lymphocyte infiltration, as a hallmark of myocarditis, was not seen in this study. Conclusion. No histological sign of myocarditis was detected in any of our cases; our findings are thus most congruent with the hypothesis of the presence of a circulating endothelium activating factor such as VEGF, originating outside of the heart, probably from the hypoxic part of the Covid-19 lungs.
- Published
- 2022
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36. Proteomic Analysis of Pleural Effusions from COVID-19 Deceased Patients: Enhanced Inflammatory Markers.
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Razaghi A, Szakos A, Alouda M, Bozóky B, Björnstedt M, and Szekely L
- Abstract
Critically ill COVID-19 patients with pleural effusion experience longer hospitalization, multisystem inflammatory syndrome, and higher rates of mortality. Generally, pleural effusion can serve as a diagnostic value to differentiate cytokine levels. This study aimed to evaluate the pleural effusions of COVID-19 deceased patients for 182 protein markers. Olink
® Inflammation and Organ Damage panels were used to determine the level of 184 protein markers, e.g., ADA, BTC, CA12, CAPG, CD40, CDCP1, CXCL9, ENTPD2, Flt3L, IL-6, IL-8, LRP1, OSM, PD-L1, PTN, STX8, and VEGFA, which were raised significantly in COVID-19 deceased patients, showing over-stimulation of the immune system and ravaging cytokine storm. The rises of DPP6 and EDIL3 also indicate damage caused to arterial and cardiovascular organs. Overall, this study confirms the elevated levels of CA12, CD40, IL-6, IL-8, PD-L1, and VEGFA, proposing their potential either as biomarkers for the severity and prognosis of the disease or as targets for therapy. Particularly, this study reports upregulated ADA, BTC, DPP6, EDIL3, LIF, ENTPD2, Flt3L, and LRP1 in severe COVID-19 patients for the first time. Pearson's correlation coefficient analysis indicates the involvement of JAK/STAT pathways as a core regulator of hyperinflammation in deceased COVID-19 patients, suggesting the application of JAK inhibitors as a potential efficient treatment., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationship that could be construed as a potential conflict of interest.- Published
- 2022
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37. Drug-induced tumor-specific cytotoxicity in a whole tissue ex vivo model of human pancreatic ductal adenocarcinoma.
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Moro CF, Selvam AK, Ghaderi M, Pimenoff VN, Gerling M, Bozóky B, Elduayen SP, Dillner J, and Björnstedt M
- Abstract
Pancreatic ductal adenocarcinoma (PDAC) is the most common type of pancreatic cancer. PDAC has a dismal prognosis and an inherent resistance to cytostatic drugs. The lack of reliable experimental models is a severe limitation for drug development targeting PDAC. We have employed a whole tissue ex vivo culture model to explore the effect of redox-modulation by sodium selenite on the viability and growth of PDAC. Drug-resistant tumors are more vulnerable to redox-active selenium compounds because of high metabolic activity and redox imbalance. Sodium selenite efficiently and specifically reduced PDAC cell viability (p <0.02) (n=8) and decreased viable de novo tumor cell outgrowth (p<0.05) while preserving non-neoplastic tissues. Major cellular responses (damaged tumor cells > 90%, tumor regression grades III-IV according to Evans) were observed for sodium selenite concentrations between 15-30 µM. Moreover, selenium levels used in this study were significantly below the previously reported maximum tolerated dose for humans. Transcriptome data analysis revealed decreased expression of genes known to drive PDAC growth and metastatic potential (CEMIP, DDR2, PLOD2, P4HA1) while the cell death-inducing genes (ATF3, ACHE) were significantly upregulated (p<0.0001). In conclusion, we report that sodium selenite has an extraordinary efficacy and specificity against drug-resistant pancreatic cancer in an organotypic slice culture model. Our ex vivo organotypic tissue slice culture model can be used to test a variety of drug candidates for swift and reliable drug responses to individual PDAC cases., Competing Interests: MB is listed as an inventor in a patent application for i.v. use of inorganic selenium in cancer patients and holds shares in SELEQ OY, a company involved in the development of Se-based formulations for prevention and treatment. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Moro, Selvam, Ghaderi, Pimenoff, Gerling, Bozóky, Elduayen, Dillner and Björnstedt.)
- Published
- 2022
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38. Soluble PD-L1 Expression After Intravenous Treatment of Cancer Patients With Selenite in Phase I Clinical Trial.
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Razaghi A, Mansouri L, Brodin O, Björnstedt M, and Lundahl J
- Abstract
A high expression level of programmed death-ligand 1 (PD-L1) is observed in different types of cancers (particularly lung cancer). Soluble (s)PD-L1 may be used as a prognostic marker and a target for anti-cancer immunity, as well as, predicting gene therapy or systemic immunotherapy in blocking the PD-1 and PD-L1 checkpoint. Studies that evaluate the effects of the immune regulator selenium on PD-L1 expression show ambiguous results. Thus, we aimed to analyze sPD-L1 levels in samples from patients who underwent different dosages of selenite treatment in phase I clinical trial. We hypothesized that selenite modulates the sPD-L1 levels in the plasma as a consequence of the suggested mode of action of selenotherapy in cancer patients. In conclusion, our results support the view that selenotherapy does not substantially affect the PD-1/PD-L1 axis judged by sPD-L1 analysis. Furthermore, no significant correlation was observed between the survival and sPD-L1 expression nor sPD-L1 changes. However, due to a dynamic individual sPD-L1 profile and a high variation in survival, we suggest that further studies are needed to identify whether individual patients can be benefited from combinational seleno- and anti-PD-L1 therapy., Competing Interests: MB is listed as an inventor in a patent application for i.v. use of inorganic selenium in cancer patients and holds shares in SELEQ OY, a company involved in the development of Se-based formulations for prevention and treatment. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Razaghi, Mansouri, Brodin, Björnstedt and Lundahl.)
- Published
- 2022
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39. Can laboratory x-ray virtual histology provide intraoperative 3D tumor resection margin assessment?
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Twengström W, Moro CF, Romell J, Larsson JC, Sparrelid E, Björnstedt M, and Hertz HM
- Abstract
Purpose: Surgery is an essential part of the curative plan for most patients affected with solid tumors. The outcome of such surgery, e.g., recurrence rates and ultimately patient survival, depends on several factors where the resection margin is of key importance. Presently, the resection margin is assessed by classical histology, which is time-consuming (several days), destructive, and basically only gives two-dimensional information. Clearly, it would be advantageous if immediate feedback on tumor extension in all three dimensions were available to the surgeon intraoperatively. Approach: We investigate a laboratory propagation-based phase-contrast x-ray computed tomography system that provides the resolution, the contrast, and, potentially, the speed for this purpose. The system relies on a liquid-metal jet microfocus source and a scintillator-coated CMOS detector. Our study is performed on paraffin-embedded non-stained samples of human pancreatic neuroendocrine tumors, liver intrahepatic cholangiocarcinoma, and pancreatic serous cystic neoplasm (benign). Results: We observe tumors with distinct and sharp edges having cellular resolution ( ∼ 10 μ m ) as well as many assisting histological landmarks, allowing for resection margin assessment. All x-ray data are compared with classical histology. The agreement is excellent. Conclusion: We conclude that the method has potential for intraoperative three-dimensional virtual histology., (© 2022 The Authors.)
- Published
- 2022
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40. Methods for accurate and reproducible studies of pharmacological effects of selenium in cancer.
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Selvam AK, Szekerczés T, Björnstedt S, Razaghi A, and Björnstedt M
- Subjects
- Cysteine metabolism, Humans, Selenoproteins, Neoplasms drug therapy, Selenium metabolism, Selenium pharmacology, Selenium therapeutic use, Selenium Compounds metabolism, Selenium Compounds pharmacology, Selenium Compounds therapeutic use
- Abstract
Selenium compounds have pronounced effects on cell growth and proliferation. Nutritional levels induce selenoproteins. However, the antineoplastic effects of supra-nutritional selenium levels are not mediated by selenoproteins. The most studied compound, selenite, was shown in a clinical trial to possess extraordinary pharmacological properties. The uptake of selenite as for GS-Se-SG and selenocystine is dependent on the extracellular reducing environment maintained by the X
c - cystine transporter (xc - antiporter) ensuring a high level of extracellular cysteine. The expression of the xc - antiporter is vital for selenium cytotoxicity and any xenobiotic or media constituents modulating the expression of this antiporter will greatly affect the cellular response. Cytotoxicity determinations are often difficult to interpret and repeat due to differences in culture conditions. In the current chapter, factors influencing the cellular response, e.g., media composition, cell culturing conditions, assays for key enzymes of importance for selenium metabolism and effects, along with selenium mediated modulation of microRNA expression and immune responses are treated., Competing Interests: Conflicts of interest M.B. is listed as an inventor in a patent application for i.v. use of inorganic selenium in cancer patients and holds shares in SELEQ OY, a company involved in the development of Se-based formulations for prevention and treatment., (Copyright © 2022 Elsevier Inc. All rights reserved.)- Published
- 2022
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41. Copy number alteration of the interferon gene cluster in cancer: Individual patient data meta-analysis prospects to personalized immunotherapy.
- Author
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Razaghi A, Brusselaers N, Björnstedt M, and Durand-Dubief M
- Abstract
Interferon (IFN) therapy has been the standard of care for a variety of cancers for decades due to the pleiotropic actions of IFNs against malignancies. However, little is known about the role of copy number alteration (CNA) of the IFN gene cluster, located at the 9p21.3, in cancer. This large individual patient data meta-analysis using 9937 patients obtained from cBioportal indicates that CNA of the IFN gene cluster is prevalent among 24 cancer types. Two statistical approaches showed that notably deletion of this cluster is significantly associated with increased mortality in many cancer types particularly uterus (OR = 2.71), kidney (OR = 2.26), and brain (OR = 2.08) cancers. The Cancer Genome Atlas PanCancer analysis also showed that CNA of the IFN gene cluster is significantly associated with decreased overall survival. For instance, the overall survival of patients with brain glioma reduced from 93m (diploidy) to 24m (with the CNA of the IFN gene). In conclusion, the CNA of the IFN gene cluster is associated with increased mortality and decreased overall survival in cancer. Thus, in the prospect of immunotherapy, CNA of IFN gene may be a useful biomarker to predict the prognosis of patients and also as a potential companion diagnostic test to prescribe IFN α/β therapy., Competing Interests: Declaration of Competing Interest The authors declare that they have no competing interests., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)
- Published
- 2021
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42. Severe features during outbreak but low mortality observed immediately before and after a March-May 2020 COVID-19 outbreak in Stockholm, Sweden.
- Author
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Pimenoff VN, Björnstedt M, and Dillner J
- Subjects
- Disease Outbreaks, Humans, SARS-CoV-2, Sweden epidemiology, COVID-19
- Abstract
Objectives: The aim of this study was to estimate how well the excess mortality reflected the burden of coronavirus disease 2019 (COVID-19)-related deaths during the March-May 2020 COVID-19 outbreak in Stockholm, Sweden, and whether the excess mortality during the outbreak might have resulted in a compensatory reduced mortality after the outbreak., Methods: Using previous 10-year or 5-year average mortality rates as a baseline, the excess mortality estimates before, during, and after the COVID-19 outbreak in March-May 2020 in Stockholm were compared., Results: Weekly death estimates revealed that the immediate pre-outbreak and post-outbreak all-cause mortality did not exceed to excess mortality regardless of whether previous 10-year or 5-year average mortality was used. Forty-three days after the start of the outbreak, 74.4% of the total excess mortality was reportedly explained by known COVID-19-related deaths, and the present study reports an update, showing that 15 weeks after the start of the outbreak, the reported COVID-19-related deaths explained >99% of the total excess mortality., Conclusions: An exceptional outbreak feature of rapid excess mortality was observed. However, no excess but similarly low mortality was observed immediately prior to the outbreak and post-outbreak, thus emphasizing the severity of the first wave of the COVID-19 outbreak in Stockholm., (Copyright © 2021 The Author(s). Published by Elsevier Ltd.. All rights reserved.)
- Published
- 2021
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43. Selenium stimulates the antitumour immunity: Insights to future research.
- Author
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Razaghi A, Poorebrahim M, Sarhan D, and Björnstedt M
- Subjects
- Humans, Selenium pharmacology, Tumor Microenvironment, Immune System drug effects, Neoplasms drug therapy, Selenium therapeutic use
- Abstract
Selenium is an essential trace element for regulating immune functions through redox-regulating activity of selenoproteins (e.g. glutathione peroxidase), protecting immune cells from oxidative stress. However, in cancer, selenium has biological bimodal action depending on the concentration. At nutritional low doses, selenium, depending on its form, may act as an antioxidant, protecting against oxidative stress, supporting cell survival and growth, thus, plays a chemo-preventive role; while, at supra-nutritional higher pharmacological doses, selenium acts as pro-oxidant inducing redox signalling and cell death. To date, many studies have been conducted on the benefits of selenium intake in reducing the risk of cancer incidence at the nutritional level, indicating that likely selenium functions as an immunostimulator, i.e. reversing the immunosuppression in tumour microenvironment towards antitumour immunity by activating immune cells (e.g. M
1 macrophages and CD8+ T-lymphocytes) and releasing pro-inflammatory cytokines such as interferon-gamma; whereas, fewer studies have explored the effects of supra-nutritional or pharmacological doses of selenium in cancer immunity. This review, thus, systematically analyses the current knowledge about how selenium stimulates the immune system against cancer and lay the groundwork for future research. Such knowledge can be promising to design combinatorial therapies with Selenium-based compounds and other modalities like immunotherapy to lower the adverse effects and increase the efficacy of treatments., Competing Interests: Conflict of interest statement M.B. is listed as an inventor in a patent application for i.v. use of inorganic selenium in cancer patients and holds shares in SELEQ OY, a company involved in the development of Se-based formulations for prevention and treatment. All remaining authors have declared no conflicts of interest., (Copyright © 2021 The Author(s). Published by Elsevier Ltd.. All rights reserved.)- Published
- 2021
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44. A Novel mRNA-Mediated and MicroRNA-Guided Approach to Specifically Eradicate Drug-Resistant Hepatocellular Carcinoma Cell Lines by Se-Methylselenocysteine.
- Author
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Selvam AK, Jawad R, Gramignoli R, Achour A, Salter H, and Björnstedt M
- Abstract
Despite progress in the treatment of non-visceral malignancies, the prognosis remains poor for malignancies of visceral organs and novel therapeutic approaches are urgently required. We evaluated a novel therapeutic regimen based on treatment with Se-methylselenocysteine (MSC) and concomitant tumor-specific induction of Kynurenine aminotransferase 1 (KYAT1) in hepatocellular carcinoma (HCC) cell lines, using either vector-based and/or lipid nanoparticle-mediated delivery of mRNA. Supplementation of MSC in KYAT1 overexpressed cells resulted in significantly increased cytotoxicity, due to ROS formation, as compared to MSC alone. Furthermore, microRNA antisense-targeted sites for miR122, known to be widely expressed in normal hepatocytes while downregulated in hepatocellular carcinoma, were added to specifically limit cytotoxicity in HCC cells, thereby limiting the off-target effects. KYAT1 expression was significantly reduced in cells with high levels of miR122 supporting the concept of miR-guided induction of tumor-specific cytotoxicity. The addition of alpha-ketoacid favored the production of methylselenol, enhancing the cytotoxic efficacy of MSC in HCC cells, with no effects on primary human hepatocytes. Altogether, the proposed regimen offers great potential to safely and specifically target hepatic tumors that are currently untreatable.
- Published
- 2021
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45. Selenofolate inhibits the proliferation of IGROV1 cancer cells independently from folate receptor alpha.
- Author
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Razaghi A, Zickler AM, Spallholz J, Kirsch G, and Björnstedt M
- Abstract
Cancer is one of the main causes of human mortality worldwide and novel chemotherapeutics are required due to the limitations of conventional cancer therapies. For example, using redox selenium compounds as novel chemotherapeutics seem to be very promising. The objective of this study was to explore if folate could be used as a carrier to deliver a newly synthesised selenium derivative selenofolate into cancer cells. Particularly, the cytotoxic effects of this selenofolate compound were investigated in a variety of cancer cell types including lung, liver, and cervical cancers and specifically IGROV1 cells. Our results showed that selenofolate inhibits the growth of cancer cells in-vitro . However, despite the expectations, folate receptor alpha (FRα) was not involved in the transportation of selenofolate compound into the cells i.e. growth inhibition was independent of FRα, suggesting that multiple transporters ( e.g. reduced folate carrier-1) are possibly involved in the delivery and internalisation of folate in IGROV1 cells. Additionally, selenofolate did not exert cell death through apoptosis. Instead, anti-proliferative activity showed to be the main cause of growth inhibition of selenolofate in the IGROV1 cell line. In conclusion, selenofolate inhibits the growth of cancer cells and thus, may be explored further as a potential chemotherapeutic agent., Competing Interests: The authors declare the following conflict of interests: Mikael Björnstedt is listed as the inventor of a patent application concerning the use of intravenous inorganic selenium in the treatment of cancer patients. Mikael Björnstedt is also a shareholder in a company, SELEQ OY, which develops selenium formulations for supplements and pharmaceutical formulations for the treatment of cancer., (© 2021 The Authors.)
- Published
- 2021
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46. Estimating Total Excess Mortality During a Coronavirus Disease 2019 Outbreak in Stockholm, Sweden.
- Author
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Pimenoff VN, Elfström M, Baussano I, Björnstedt M, and Dillner J
- Subjects
- Disease Outbreaks, Hospitals, Humans, Mortality, SARS-CoV-2, Sweden epidemiology, COVID-19
- Abstract
Total excess mortality peaked during a coronavirus disease 2019 (COVID-19) outbreak in Stockholm, but 25% of these deaths were not recognized as COVID-19 related nor occurred in hospitals. Estimate of total excess mortality may give a more comprehensive picture of the total disease burden during a COVID-19 outbreak, and may facilitate managing future outbreaks., (© The Author(s) 2020. Published by Oxford University Press for the Infectious Diseases Society of America.)
- Published
- 2021
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47. Pulmonary stromal expansion and intra-alveolar coagulation are primary causes of COVID-19 death.
- Author
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Szekely L, Bozoky B, Bendek M, Ostad M, Lavignasse P, Haag L, Wu J, Jing X, Gupta S, Saccon E, Sönnerborg A, Cao Y, Björnstedt M, and Szakos A
- Abstract
Most COVID-19 victims are old and die from unrelated causes. Here we present t welve complete autopsies, including two rapid autopsies of young patients where the cause of death was COVID-19 ARDS. The main virus induced pathology was in the lung parenchyma and not in the airways. Most coagulation events occurred in the intra-alveolar and not in the intra-vascular space and the few thrombi were mainly composed of aggregated thrombocytes. The dominant inflammatory response was the massive accumulation of CD163 + macrophages and the disappearance of T killer, NK and B-cells. The virus was replicating in the pneumocytes and macrophages but not in bronchial epithelium, endothelium, pericytes or stromal cells. The lung consolidations were produced by a massive regenerative response, stromal and epithelial proliferation and neovascularization. We suggest that thrombocyte aggregation inhibition, angiogenesis inhibition and general proliferation inhibition may have a roll in the treatment of advanced COVID-19 ARDS., Competing Interests: The authors declare no conflict of interest., (© 2021 The Authors.)
- Published
- 2021
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48. The Effect of Methylselenocysteine and Sodium Selenite Treatment on microRNA Expression in Liver Cancer Cell Lines.
- Author
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Lendvai G, Szekerczés T, Kontsek E, Selvam A, Szakos A, Schaff Z, Björnstedt M, and Kiss A
- Subjects
- Apoptosis, Biomarkers, Tumor genetics, Carcinoma, Hepatocellular drug therapy, Carcinoma, Hepatocellular genetics, Carcinoma, Hepatocellular metabolism, Cell Proliferation, Gene Expression Profiling, Humans, Liver Neoplasms drug therapy, Liver Neoplasms genetics, Liver Neoplasms metabolism, Liver Neoplasms pathology, Selenocysteine pharmacology, Trace Elements pharmacology, Tumor Cells, Cultured, Anticarcinogenic Agents pharmacology, Biomarkers, Tumor metabolism, Carcinoma, Hepatocellular pathology, Gene Expression Regulation, Neoplastic drug effects, MicroRNAs genetics, Selenocysteine analogs & derivatives, Sodium Selenite pharmacology
- Abstract
The unique character of selenium compounds, including sodium selenite and Se-methylselenocysteine (MSC), is that they exert cytotoxic effects on neoplastic cells, providing a great potential for treating cancer cells being highly resistant to cytostatic drugs. However, selenium treatment may affect microRNA (miRNA) expression as the pattern of circulating miRNAs changed in a placebo-controlled selenium supplement study. This necessitates exploring possible changes in the expression profiles of miRNAs. For this, miRNAs being critical for liver function were selected and their expression was measured in hepatocellular carcinoma (HLE and HLF) and cholangiocarcinoma cell lines (TFK-1 and HuH-28) using individual TaqMan MicroRNA Assays following selenite or MSC treatments. For establishing tolerable concentrations, IC
50 values were determined by performing SRB proliferation assays. The results revealed much lower IC50 values for selenite (from 2.7 to 11.3 μM) compared to MSC (from 79.5 to 322.6 μM). The treatments resulted in cell line-dependent miRNA expression patterns, with all miRNAs found to show fold change differences; however, only a few of these changes were statistically different in treated cells compared to untreated cells below IC50 . Namely, miR-199a in HLF, miR-143 in TFK-1 upon MSC treatment, miR-210 in HLF and TFK-1, miR-22, -24, -122, -143 in HLF upon selenite treatment. Fold change differences revealed that miR-122 with both selenium compounds, miR-199a with MSC and miR-22 with selenite were affected. The miRNAs showing minimal alterations included miR-125b and miR-194. In conclusion, our results revealed moderately altered miRNA expression in the cell lines (less alterations following MSC treatment), being miR-122, -199a the most affected and miR-125b, -194 the least altered miRNAs upon selenium treatment.- Published
- 2020
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49. Genome-wide transcriptome profiling of ex-vivo precision-cut slices from human pancreatic ductal adenocarcinoma.
- Author
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Ghaderi M, Fernández Moro C, Pouso Elduayen S, Hultin E, Verbeke CS, Björnstedt M, and Dillner J
- Subjects
- Aged, Aged, 80 and over, Apoptosis genetics, Biomarkers, Tumor genetics, Cell Movement genetics, Cell Proliferation genetics, Cyclooxygenase 2 genetics, Female, Gene Expression Profiling methods, Gene Expression Regulation, Neoplastic genetics, Genome-Wide Association Study methods, Humans, Male, Middle Aged, NF-kappa B genetics, Signal Transduction genetics, Transcription Factor AP-1 genetics, Up-Regulation genetics, Vascular Endothelial Growth Factor A genetics, Pancreatic Neoplasms, Adenocarcinoma genetics, Carcinoma, Pancreatic Ductal genetics, Pancreatic Neoplasms genetics, Transcriptome genetics
- Abstract
Ex-vivo tumor tissue culture systems are used as models to test specific anti-cancer drugs. Their main advantage is that they are closely comparable with the in vivo tumor in their host organism. We previously reported that precision-cut organotypic tissue slices of pancreatic ductal adenocarcinoma (PDAC) can be successfully cultured ex-vivo for at least 4 days. In order to study how culturing might affect transcription patterns, we now performed genome-wide transcriptome profiling of both baseline (0 h) and explanted tumors at daily intervals (24, 48 and 72 h) after start of culturing. The total-RNA from five samples of surgically resected human PDAC tumors at baseline and at different time points in culture was sequenced. Differential gene expression analysis of the whole transcriptome, testing 58,713 genes and over 206,000 transcripts, found that only a small number of genes showed significant changes in expression between baseline and cultured samples. The cultured tumor slices showed upregulation of a median of 12, 10 and 15 genes and downregulation of a median of 15, 12 and 25 genes at 24, 48 and 72 h in culture, respectively. One sample had morphologically increasing loss of tissue viability (range 0-18%). The vascular endothelial growth factor A (VEGFA) was significantly upregulated during the entire culture period in this case. Pathway over-representation analysis suggested that VEGFA together with the PTGS2 gene were upregulated at the same time as HIF-1-triggered cell apoptosis via NF-ĸB and the AP-1 activating factor was induced. Indeed, increased areas of apoptotic lesions were visible in this sample after 24 hours of culture. In conclusion, genome-wide transcriptome analysis supports that ex-vivo cultured tissue slices of PDAC may be a representative model of the original tumor. Transcriptome analysis was found to be a valuable complement to morphology for evaluation of ex-vivo cultures of PDAC.
- Published
- 2020
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50. Selenoprotein P as Biomarker of Selenium Status in Clinical Trials with Therapeutic Dosages of Selenite.
- Author
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Brodin O, Hackler J, Misra S, Wendt S, Sun Q, Laaf E, Stoppe C, Björnstedt M, and Schomburg L
- Subjects
- Biomarkers blood, Cardiovascular Diseases etiology, Female, Humans, Infusions, Intravenous, Male, Neoplasms etiology, Risk Factors, Selenium deficiency, Thyroiditis, Autoimmune etiology, Drug Dosage Calculations, Drug Monitoring methods, Selenium administration & dosage, Selenium metabolism, Selenoprotein P blood
- Abstract
Selenoprotein P (SELENOP) is an established biomarker of selenium (Se) status. Serum SELENOP becomes saturated with increasing Se intake, reaching maximal concentrations of 5-7 mg SELENOP/L at intakes of ca. 100-150 µg Se/d. A biomarker for higher Se intake is missing. We hypothesized that SELENOP may also reflect Se status in clinical applications of therapeutic dosages of selenite. To this end, blood samples from two supplementation studies employing intravenous application of selenite at dosages >1 mg/d were analyzed. Total Se was quantified by spectroscopy, and SELENOP by a validated ELISA. The high dosage selenite infusions increased SELENOP in parallel to elevated Se concentrations relatively fast to final values partly exceeding 10 mg SELENOP/L. Age or sex were not related to the SELENOP increase. Western blot analyses of SELENOP verified the results obtained by ELISA, and indicated an unchanged pattern of immunoreactive protein isoforms. We conclude that the saturation of SELENOP concentrations observed in prior studies with moderate Se dosages (<400 µg/d) may reflect an intermediate plateau of expression, rather than an absolute upper limit. Circulating SELENOP seems to be a suitable biomarker for therapeutic applications of selenite exceeding the recommended upper intake levels. Whether SELENOP is also capable of reflecting other supplemental selenocompounds in high dosage therapeutic applications remains to be investigated.
- Published
- 2020
- Full Text
- View/download PDF
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