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Updated: Jun 25, 2026
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Identification of Transcription Factor Regulators using Medium-Throughput Screening of Arrayed Libraries and a Dual-Luciferase-Based Reporter
Published on: March 27, 2020
HoxA5 stabilizes adherens junctions via increased Akt1.
Gemma Arderiu1, Ileana Cuevas, Amy Chen
1Department of Surgery, University of California San Francisco, San Francisco, California 94143, USA.
Cell Adhesion & Migration
|March 6, 2009
Summary
Restoring Homeobox A5 (HoxA5) expression in hemangioma cells normalized their morphology and behavior. HoxA5 stabilized vascular junctions by regulating Akt1 and PTEN, crucial for vascular stability.
Area of Science:
- Molecular Biology
- Developmental Biology
- Cell Biology
Background:
- Vascular development relies on cell-matrix and cell-cell interactions.
- Homeobox (Hox) genes, including HoxA5, regulate vascular remodeling by controlling matrix-degrading enzymes, integrins, and extracellular matrix (ECM) components.
- HoxA5 downregulation is observed in angiogenic endothelial cells and hemangiomas, suggesting its role in vascular abnormalities.
Purpose of the Study:
- To investigate if restoring HoxA5 expression could normalize hemangioma cell morphology and behavior.
- To elucidate the molecular mechanisms by which HoxA5 influences vascular stability.
Main Methods:
- Sustained expression of HoxA5 in murine hemangioma cell line (EOMA).
- Assessment of cell growth in vivo and morphogenesis in 3D basement membrane (BM) cultures.
- Analysis of beta-catenin localization in adherens junctions and vascular permeability.
- Investigation of the role of Akt1 and PTEN in HoxA5-mediated effects.
Main Results:
- Sustained HoxA5 expression reduced EOMA cell growth in vivo and promoted branching morphogenesis.
- HoxA5 expression increased beta-catenin retention in adherens junctions and decreased vascular permeability.
- HoxA5-induced stabilization of adherens junctions required Akt1 activity.
- HoxA5 enhanced Akt1 expression and activity by downregulating PTEN.
Conclusions:
- HoxA5 plays a critical role in coordinating a stable vascular phenotype.
- Restoring HoxA5 expression offers a potential therapeutic strategy for hemangiomas by normalizing vascular behavior.
- The HoxA5-Akt1-PTEN axis is a key pathway regulating vascular stability and junction integrity.
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