Selenium Metabolism in Cancer Cells: The Combined Application of XAS and XFM Techniques to the Problem of Selenium Speciation in Biological Systems
Abstract
:1. Introduction
2. The Selenium Speciation Problem
2.1. Dietary Selenium Compounds and Their Metabolites
2.1.1. Hyphenated Techniques and Selenium Speciation
3. Synchrotron-Based X-ray Techniques in Elemental Speciation Analysis
The Use of Synchrotron-Based X-Rays to Investigate Selenium in Biology
4. A Top-Down Approach to Investigating Selenium in Biology
4.1. Selenium Speciation Dictates Distribution in Human Lung Cancer Cells—Findings from XFM
4.2. Selenium Speciation in Bulk Cell Pellets and Single Cancer Cells
4.3. Extending XFM to Selenium in Electrophoretically-Separated Cell Lysates
5. Conclusions
Se supplement | Speciation of Se metabolites | Distribution of Se metabolites |
---|---|---|
SeMet | R–Se–R | throughout the cells, but particularly concentrated in the perinuclear region bound to proteins |
MeSeCys | mostly R–Se–R significant R–Se–Se–R component | uncertain |
Selenite | elemental Se, S–Se–S and R–Se–Se–R some R–Se–R | elemental Se concentrated in small regions throughout the cytosol Se associated with, but not bound to, Cu |
Future Directions
Acknowledgments
Conflict of Interest
References
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Weekley, C.M.; Aitken, J.B.; Finney, L.; Vogt, S.; Witting, P.K.; Harris, H.H. Selenium Metabolism in Cancer Cells: The Combined Application of XAS and XFM Techniques to the Problem of Selenium Speciation in Biological Systems. Nutrients 2013, 5, 1734-1756. https://doi.org/10.3390/nu5051734
Weekley CM, Aitken JB, Finney L, Vogt S, Witting PK, Harris HH. Selenium Metabolism in Cancer Cells: The Combined Application of XAS and XFM Techniques to the Problem of Selenium Speciation in Biological Systems. Nutrients. 2013; 5(5):1734-1756. https://doi.org/10.3390/nu5051734
Chicago/Turabian StyleWeekley, Claire M., Jade B. Aitken, Lydia Finney, Stefan Vogt, Paul K. Witting, and Hugh H. Harris. 2013. "Selenium Metabolism in Cancer Cells: The Combined Application of XAS and XFM Techniques to the Problem of Selenium Speciation in Biological Systems" Nutrients 5, no. 5: 1734-1756. https://doi.org/10.3390/nu5051734