Fluorescent mouse pheochromocytoma spheroids expressing hypoxia-inducible factor 2 alpha: Morphologic and radiopharmacologic characterization

Publikation: Beitrag in FachzeitschriftForschungsartikelBeigetragenBegutachtung

Beitragende

Abstract

BACKGROUND: Pheochromocytomas and paragangliomas (PPGLs) are rare catecholamine-producing tumors arising from chromaffin tissue. In a PPGL subgroup, dysregulation of hypoxia signaling pathways, in particular mediated through stabilization of hypoxia-inducible factor 2 alpha (HIF2α), have been suggested to drive tumorigenesis through altering downstream transcriptional activity. OBJECTIVE: This study evaluated the use of mCherry-transgenic mouse pheochromocytoma (MPCmCherry) spheroids as in vitro models for investigating consequences of HIF2α expression on aggregation behavior, morphology, growth, glucose consumption, amino acid uptake, and somatostatin type 2 receptors under stable hypoxic conditions. METHODS: MPCmCherry spheroids were monitored using confocal laser scanning microscopy. Hypoxic regions were detected using pimonidazole. Radiotracer incubation was performed using 2-[18F]fluoro-2-deoxyglucose ([18F]FDG), O-3-(2[18F]fluoroethoxy)-4-hydroxyphenylalanine ([18F]OFED), and [68Ga]Ga-(Tyr3)octreotate ([68Ga]Ga-DOTA-TATE). RESULTS: Both HIF2α-expressing and empty vector (EV) control spheroids showed regions of stable cellular hypoxia. Expression of HIF2α in MPCmCherry spheroids was associated with less symmetric morphology, faster growth, and decreased uptake of [68Ga]Ga-DOTA-TATE (somatostatin type 2 receptors) compared to controls, whereas, uptake of [18F]FDG (glucose transporter 1 and hexokinases) and [18F]OFED (system L amino acid transporter 1) remained unaffected. CONCLUSIONS: The recent study proved MPCmCherry spheroids to be complex three-dimensional tumor cell models for investigating morphologic and metabolic consequences of dysregulated hypoxia pathways under hypoxic conditions.

Details

OriginalspracheEnglisch
Seiten (von - bis)135-151
Seitenumfang17
FachzeitschriftJournal of Cellular Biotechnology
Jahrgang5
Ausgabenummer2
PublikationsstatusVeröffentlicht - 2019
Peer-Review-StatusJa

Externe IDs

ORCID /0000-0002-6932-333X/work/148144945
ORCID /0000-0002-3549-2477/work/148145336

Schlagworte

Schlagwörter

  • Amino acid transporters, confocal laser scanning microscopy, neuroendocrine tumors, paraganglioma, pimonidazole, positron emitters, radiotracer uptake, somatostatin receptors