13 July 2009 Downregulation of the autophagy protein ATG-7 correlates with distinct sphingolipid profile in MCF-7 cells sensitized to photodamage
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Proceedings Volume 7380, Photodynamic Therapy: Back to the Future; 73805M (2009); doi: 10.1117/12.827261
Event: 12th World Congress of the International Photodynamic Association, 2009, Seattle, Washington, United States
Abstract
The objective of this study was to determine the sphingolipid (SL) profile in autophagy-defective cells and overall cell death after PDT with Pc 4 (PDT). Human breast cancer MCF-7 cells with downregulated autophagy protein ATG-7 and their scrambled controls (Scr) were used. Exposure of ATG-7 knockdown cells to PDT led to defective processing of the autophagy marker LC3, and increased overall cell killing. In both cell types PDT evoked an early (2 h) increase in ceramides and dihydroceramides (DHceramides). When the two cell types were compared regarding time (2 and 24 h) and treatment conditions (with and without PDT), the levels of several ceramides and DHceramides were reduced, whereas the concentrations of C14-ceramide, C16-ceramide and C12-DHceramide were higher in ATG-7 knockdown cells. The data imply that the SL profile might be a marker of autophagy-deficiency in cells sensitized to PDT.
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Duska Separovic, Ameeta Kelekar, Adi L. Tarca, Jacek Bielawski, David Kessel, "Downregulation of the autophagy protein ATG-7 correlates with distinct sphingolipid profile in MCF-7 cells sensitized to photodamage", Proc. SPIE 7380, Photodynamic Therapy: Back to the Future, 73805M (13 July 2009); doi: 10.1117/12.827261; https://doi.org/10.1117/12.827261
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KEYWORDS
Photodynamic therapy

Stereolithography

Proteins

Control systems

Cancer

Molecules

Statistical analysis

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