» Articles » PMID: 40048186

The TCF4 Gene Regulates Apoptosis of Corneal Endothelial Cells in Fuchs Endothelial Corneal Dystrophy

Abstract

Purpose: Fuchs endothelial corneal dystrophy (FECD) is a progressive corneal disorder characterized by excessive extracellular matrix (ECM) accumulation and corneal endothelial cell death. CTG trinucleotide repeat expansion in the transcription factor 4 (TCF4) gene represents the most significant genetic risk factor. This study aimed to elucidate the role of TCF4 in FECD pathogenesis through comprehensive proteomic analysis.

Methods: Corneal endothelial cells isolated from patients with FECD harboring TCF4 trinucleotide repeat expansion were immortalized to establish an FECD cell model (iFECD). CRISPR/Cas9-mediated genome editing was employed to generate TCF4-knockout iFECD cells. Whole-cell proteome analysis was performed using liquid chromatography-mass spectrometry, followed by pathway enrichment analysis of differentially expressed proteins (DEPs). The effects of TCF4 deletion on TGF-β-mediated protein aggregation and cell death were evaluated using Western blot analysis, flow cytometry, and aggresome detection assays.

Results: Proteomic analysis identified 88 DEPs among 6510 detected proteins. Pathway analysis revealed significant enrichment in ECM-associated pathways, oxidative stress responses, and cellular motility. TCF4 deletion attenuated TGF-β-induced cell death in iFECD cells. Concordantly, Western blot analysis demonstrated that TCF4 deletion suppressed TGF-β2-mediated cleavage of caspase-3 and poly (ADP-ribose) polymerase. Flow cytometric analysis of Annexin V-positive cells confirmed reduced apoptosis in TCF4-deleted cells following TGF-β2 treatment. Additionally, aggresome detection assays revealed that TCF4 deletion diminished TGF-β2-induced protein aggregation.

Conclusions: This study demonstrates a crucial role for TCF4 in FECD pathogenesis, particularly in ECM regulation and protein aggregation-induced cell death.

References
1.
Eghrari A, Vahedi S, Afshari N, Riazuddin S, Gottsch J . CTG18.1 Expansion in TCF4 Among African Americans With Fuchs' Corneal Dystrophy. Invest Ophthalmol Vis Sci. 2017; 58(14):6046-6049. PMC: 5710628. DOI: 10.1167/iovs.17-21661. View

2.
Zhang C, Wei S, Sun W, Teng K, Dai M, Wang F . Super-enhancer-driven AJUBA is activated by TCF4 and involved in epithelial-mesenchymal transition in the progression of Hepatocellular Carcinoma. Theranostics. 2020; 10(20):9066-9082. PMC: 7415796. DOI: 10.7150/thno.45349. View

3.
Riazuddin S, Vithana E, Seet L, Liu Y, Al-Saif A, Koh L . Missense mutations in the sodium borate cotransporter SLC4A11 cause late-onset Fuchs corneal dystrophy. Hum Mutat. 2010; 31(11):1261-8. PMC: 2970683. DOI: 10.1002/humu.21356. View

4.
Kuyumcu-Martinez N, Wang G, Cooper T . Increased steady-state levels of CUGBP1 in myotonic dystrophy 1 are due to PKC-mediated hyperphosphorylation. Mol Cell. 2007; 28(1):68-78. PMC: 2083558. DOI: 10.1016/j.molcel.2007.07.027. View

5.
Forrest M, Waite A, Martin-Rendon E, Blake D . Knockdown of human TCF4 affects multiple signaling pathways involved in cell survival, epithelial to mesenchymal transition and neuronal differentiation. PLoS One. 2013; 8(8):e73169. PMC: 3751932. DOI: 10.1371/journal.pone.0073169. View