Format

Send to

Choose Destination
J Biol Chem. 2016 May 6;291(19):10089-103. doi: 10.1074/jbc.M115.688879. Epub 2016 Mar 9.

Multidrug Resistance-associated Protein-1 (MRP-1)-dependent Glutathione Disulfide (GSSG) Efflux as a Critical Survival Factor for Oxidant-enriched Tumorigenic Endothelial Cells.

Author information

1
From the Department of Plastic Surgery, Davis Heart and Lung Research Institute, and gayle.gordillo@osumc.edu.
2
From the Department of Plastic Surgery, Davis Heart and Lung Research Institute, and.
3
Davis Heart and Lung Research Institute, and Department of Surgery.
4
Center for Biostatistics, Ohio State University Wexner Medical Center, Columbus, Ohio 43212.

Abstract

Endothelial cell tumors are the most common soft tissue tumors in infants. Tumor-forming endothelial (EOMA) cells are able to escape cell death fate despite excessive nuclear oxidant burden. Our previous work recognized perinuclear Nox-4 as a key contributor to EOMA growth. The objective of this work was to characterize the mechanisms by which EOMA cells evade oxidant toxicity and thrive. In EOMA cells, compared with in the cytosol, the nuclear GSSG/GSH ratio was 5-fold higher. Compared to the ratio observed in healthy murine aortic endothelial (MAE) cells, GSSG/GSH was over twice as high in EOMA cells. Multidrug resistance-associated protein-1 (MRP-1), an active GSSG efflux mechanism, showed 2-fold increased activity in EOMA compared with MAE cells. Hyperactive YB-1 and Ape/Ref-1 were responsible for high MRP-1 expression in EOMA. Proximity ligand assay demonstrated MRP-1 and YB-1 binding. Such binding enabled the nuclear targeting of MRP-1 in EOMA in a leptomycin-B-sensitive manner. MRP-1 inhibition as well as knockdown trapped nuclear GSSG, causing cell death of EOMA. Disulfide loading of cells by inhibition of GSSG reductase (bischoloronitrosourea) or thioredoxin reductase (auranofin) was effective in causing EOMA death as well. In sum, EOMA cells survive a heavy oxidant burden by rapid efflux of GSSG, which is lethal if trapped within the cell. A hyperactive MRP-1 system for GSSG efflux acts as a critical survival factor for these cells, making it a potential target for EOMA therapeutics.

KEYWORDS:

Ape/Ref-1; NADPH oxidase; Nox-4; YB-1; endothelial cell; multidrug transporter; thioredoxin; tumor

PMID:
26961872
PMCID:
PMC4858962
DOI:
10.1074/jbc.M115.688879
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for HighWire Icon for PubMed Central
Loading ...
Support Center