HIF2α-Dependent Lipid Storage Promotes Endoplasmic Reticulum Homeostasis in Clear-Cell Renal Cell Carcinoma

©2015 American Association for Cancer Research..

UNLABELLED: Two hallmarks of clear-cell renal cell carcinoma (ccRCC) are constitutive hypoxia-inducible factor (HIF) signaling and abundant intracellular lipid droplets (LD). However, regulation of lipid storage and its role in ccRCC are incompletely understood. Transcriptional profiling of primary ccRCC samples revealed that expression of the LD coat protein gene PLIN2 was elevated in tumors and correlated with HIF2α, but not HIF1α, activation. HIF2α-dependent PLIN2 expression promoted lipid storage, proliferation, and viability in xenograft tumors. Mechanistically, lipid storage maintained integrity of the endoplasmic reticulum (ER), which is functionally and physically associated with LDs. Specifically, PLIN2-dependent lipid storage suppressed cytotoxic ER stress responses that otherwise result from elevated protein synthetic activity characteristic of ccRCC cells. Thus, in addition to promoting ccRCC proliferation and anabolic metabolism, HIF2α modulates lipid storage to sustain ER homeostasis, particularly under conditions of nutrient and oxygen limitation, thereby promoting tumor cell survival.

SIGNIFICANCE: We demonstrate that HIF2α promotes lipid storage, ER homeostasis, and cell viability in ccRCC via upregulation of the LD coat protein PLIN2, revealing a novel function for the well-documented "clear-cell" phenotype and identifying ER stress as a targetable vulnerability created by HIF2α/PLIN2 suppression in this common renal malignancy.

Errataetall:

CommentIn: Cancer Discov. 2015 Jun;5(6):584-5. - PMID 26037916

Medienart:

E-Artikel

Erscheinungsjahr:

2015

Erschienen:

2015

Enthalten in:

Zur Gesamtaufnahme - volume:5

Enthalten in:

Cancer discovery - 5(2015), 6 vom: 15. Juni, Seite 652-67

Sprache:

Englisch

Beteiligte Personen:

Qiu, Bo [VerfasserIn]
Ackerman, Daniel [VerfasserIn]
Sanchez, Danielle J [VerfasserIn]
Li, Bo [VerfasserIn]
Ochocki, Joshua D [VerfasserIn]
Grazioli, Alison [VerfasserIn]
Bobrovnikova-Marjon, Ekaterina [VerfasserIn]
Diehl, J Alan [VerfasserIn]
Keith, Brian [VerfasserIn]
Simon, M Celeste [VerfasserIn]

Links:

Volltext

Themen:

1B37H0967P
Basic Helix-Loop-Helix Transcription Factors
Endothelial PAS domain-containing protein 1
Journal Article
Membrane Proteins
PLIN2 protein, human
Perilipin-2
Plin2 protein, mouse
Research Support, N.I.H., Extramural
Research Support, Non-U.S. Gov't

Anmerkungen:

Date Completed 02.06.2016

Date Revised 11.03.2022

published: Print-Electronic

CommentIn: Cancer Discov. 2015 Jun;5(6):584-5. - PMID 26037916

Citation Status MEDLINE

doi:

10.1158/2159-8290.CD-14-1507

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM247624349