HIF1A transcriptional regulation of COX4I2 impacts angiogenesis in pheochromocytoma

Copyright © 2024. Published by Elsevier Inc..

BACKGROUND: Pheochromocytoma (PCC) is a rare neuroendocrine tumor. Angiogenesis is primary contributing factor for tumorigenesis. Cytochrome c oxidase 4I2 (COX4I2) has been confirmed to take part in the progression of cancer. Hypoxia-inducible factor 1A (HIF1A) is the main regulatory factor for the steady-state response of hypoxia, involved in metabolism and angiogenesis. In this study, we intended to explore the functions of COX4I2 in PCC and the effect mechanism between HIF1A and COX4I2.

MATERIALS AND METHODS: The RNA-sequencing and immunohistochemistry tested COX4I2 expression in highly vascular PCC. Small interfering RNA (siRNA) was used to reduce the mRNA expression of COX4I2, and a small molecule inhibitor was utilized to reduce the protein expression of HIF1A. Culturing cells in 1% O2environment was performed to activate HIF1A. Western blot was applied to quantify the expression of target genes at the protein levels. The supernatant from PCC cells and fibroblasts acted as the conditioned medium. We conducted the tube formation and transwell assays in human vascular endothelial cells (HUVECs) to determine angiogenesis, the binding of COX4I2 promoter and HIF1A was evaluated by the dual luciferase reporter assay.

RESULTS: COX4I2 had been rigorously shown to be overexpressed in highly vascular PCC. Knockdown of COX4I2 in PCC cells (MPC) did not significantly impact angiogenesis, while knockdown of COX4I2 in fibroblast (3T3) notably inhibited angiogenesis. RNA sequencing suggested that the expression of 11 vascular markers, such as CD34 and angiogenesis associated pathways in 3T3, decreased with knockdown of COX4I2. HIF1A had been shown to enhance the mRNA expression of COX4I2 through transcriptional regulation. Activation and inhibition of HIF1A resulted in upregulation and downregulation of COX4I2, respectively. The HIF1A inhibitor demonstrated a reduction in angiogenesis.

CONCLUSION: COX4I2 is overexpressed in highly vascular PCC and contributes to angiogenesis in fibroblasts. Mechanistically, HIF1A transcriptional regulation enhances COX4I2 and its effects on angiogenesis in PCC. COX4I2 might serve as a vascular marker and represent a potential target for vascular therapy.

Medienart:

E-Artikel

Erscheinungsjahr:

2024

Erschienen:

2024

Enthalten in:

Zur Gesamtaufnahme - volume:704

Enthalten in:

Biochemical and biophysical research communications - 704(2024) vom: 16. März, Seite 149638

Sprache:

Englisch

Beteiligte Personen:

Li, Xiuci [VerfasserIn]
Zhuo, Ran [VerfasserIn]
Mao, Yongxin [VerfasserIn]
Fang, Chen [VerfasserIn]
Dai, Jun [VerfasserIn]
Ye, Lei [VerfasserIn]
Wang, Chenghe [VerfasserIn]
Sun, Fukang [VerfasserIn]

Links:

Volltext

Themen:

Angiogenesis
COX4I2
COX4I2 protein, human
EC 1.9.3.1
Electron Transport Complex IV
Fibroblast
HIF1A
HIF1A protein, human
Hypoxia-Inducible Factor 1, alpha Subunit
Journal Article
Pheochromocytoma
RNA, Messenger
RNA, Small Interfering

Anmerkungen:

Date Completed 13.03.2024

Date Revised 13.03.2024

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1016/j.bbrc.2024.149638

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM369127927