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Updated: Sep 27, 2026
Analysis of Retinoic Acid-induced Neural Differentiation of Mouse Embryonic Stem Cells in Two and Three-dimensional Embryoid Bodies
Published on: April 22, 2017
Gene expression networks underlying retinoic acid-induced differentiation of human retinoblastoma cells
Aimin Li1, Xuemei Zhu, Bruce Brown
1Mary D Allen Laboratory for Vision Research, Doheny Eye Institute, and Department of Cell and Neurobiology, The Keck School of Medicine of the University of Southern California, Los Angeles, California 90089-9112, USA. ccraft@usc.edu
Purpose:
To understand the genetic regulatory pathways underlying the retinoic acid (RA) induction of cone arrestin, gene array technology and other molecular tools were used to profile global gene expression changes in human retinoblastoma cells.
Methods:
Weri-Rb-1 retinoblastoma cells were cultured in the absence or presence of RA for various periods. DNA microarray analysis profiled gene expression followed by real-time PCR and Northern and immunoblot analyses to confirm the change in expression of selected retinal genes and their gene products. Additional methodology included flow cytometry analysis, immunocytochemistry, and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) assay.
Results:
DNA microarray analysis of approximately 6800 genes revealed RA-induced upregulation of cone-specific genes and downregulation of rod-specific genes in Weri-Rb-1 cells. Other significantly upregulated mRNAs included chicken ovalbumin upstream promoter-transcription factor (COUP-TF1), retinoid X receptor (RXR)-gamma, thyroid hormone receptor (TR)-beta2, and guanylyl cyclase-activating protein (GCAP)-1. Real-time PCR and/or Northern blot analysis confirmed the expression changes of a subset of genes including the upregulation of a pineal- and retina-specific transcription factor, CRX. RA treatment also led to G(0)/G(1) cell cycle arrest and increased both the intensity of human cone arrestin (hCAR)-immunoreactivity and the number of apoptotic cells. The cell-cycle-arrest stage correlated with the observed microarray results in which the RA treatment downregulated critical genes such as cyclins (cyclin E, cyclin D3) and cyclin-dependent kinases (CDK5, CDK10).
Conclusions:
These data suggest that RA induces a subpopulation of retinoblastoma cells to differentiate toward a cone cell lineage while selectively leading other cells into apoptosis.
Insights
Retinoic acid (RA) treatment of retinoblastoma cells promotes cone cell differentiation and apoptosis. Gene expression analysis revealed changes in cone-specific genes and cell cycle regulators.
Area of Science:
- Retinal cell biology
- Molecular oncology
- Gene regulation
Background:
- Retinoblastoma is a pediatric eye cancer with complex genetic underpinnings.
- Retinoic acid (RA) is known to influence cell differentiation and development.
- Understanding RA's effects on retinoblastoma is crucial for potential therapeutic strategies.
Purpose of the Study:
- To elucidate the genetic regulatory pathways involved in retinoic acid (RA) induction of cone arrestin.
- To profile global gene expression changes in human retinoblastoma cells treated with RA.
- To investigate RA's impact on cell cycle and apoptosis in retinoblastoma.
Main Methods:
- Human retinoblastoma Weri-Rb-1 cells were cultured with or without RA.
- DNA microarray analysis was performed to profile gene expression.
- Real-time PCR, Northern blot, immunoblot, flow cytometry, and TUNEL assays were used for validation and further analysis.
Main Results:
- RA treatment upregulated cone-specific genes and downregulated rod-specific genes.
- Key transcription factors (CRX, COUP-TF1) and receptors (RXR-gamma, TR-beta2) were modulated.
- RA induced G(0)/G(1) cell cycle arrest and increased apoptosis, correlating with altered cyclin and CDK expression.
Conclusions:
- RA induces differentiation towards a cone cell lineage in a subpopulation of retinoblastoma cells.
- RA selectively triggers apoptosis in other retinoblastoma cells.
- These findings highlight RA's dual role in retinoblastoma cell fate determination.
