Downregulation of the autophagy protein ATG-7 correlates with distinct sphingolipid profile in MCF-7 cells sensitized to photodamage

Duska Separovic, Ameeta Kelekar, Adi L. Tarca, Jacek Bielawski, David Kessel

Research output: Chapter in Book/Report/Conference proceedingConference contribution

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.

Original languageEnglish (US)
Title of host publication12th World Congress of the International Photodynamic Association - Photodynamic Therapy
Subtitle of host publicationBack to the Future
DOIs
StatePublished - Dec 1 2009
Event12th World Congress of the International Photodynamic Association - Photodynamic Therapy: Back to the Future - Seattle, WA, United States
Duration: Jun 11 2009Jun 15 2009

Publication series

NameProgress in Biomedical Optics and Imaging - Proceedings of SPIE
Volume7380
ISSN (Print)1605-7422

Other

Other12th World Congress of the International Photodynamic Association - Photodynamic Therapy: Back to the Future
CountryUnited States
CitySeattle, WA
Period6/11/096/15/09

Keywords

  • Autophagy
  • PDT
  • ceramide
  • dihydroceramide
  • sphingosine

Fingerprint Dive into the research topics of 'Downregulation of the autophagy protein ATG-7 correlates with distinct sphingolipid profile in MCF-7 cells sensitized to photodamage'. Together they form a unique fingerprint.

Cite this