Abstract
Purpose :
Cultured human corneal endothelial cells (cHCECs) have an inclination towards cell-state transition (CST) into a senescence phenotype and epithelium-mesenchymal transition (EMT). MicroRNA (miR) is essential in regulating many cellular processes, including remodeling of the extracellular matrix, which is closely linked to CST in cHCECS. We investigated the linkage of dysregulated expression of miRs with the pathogenesis of bullous keratopathy (BK) and Fuchs’ corneal endothelial corneal dystrophy (FECD).
Methods :
Variations of cHCECs in their composition of heterogeneous subpopulations were verified in regard to their surface cluster determinant (CD) markers and morphology. The profiles of miRs in cultured cells were detected by 3D-Gene® DNA Chip array (Toray), and also analyzed in fresh corneal tissues with distinct endothelial cell densities (ECDs) with or without guttata. To validate the 3D-Gene® DNA Chip results, qRT-PCR was carried out. RNAs were extracted from cHCECs transfected with selected miRs, and target genes were presumed by PCR array (Qiagen).
Results :
Unique miR expression profiles, including up- and downregulated miR clusters, were found in cHCECs. Some miR isoforms were also greatly upregulated in fresh corneal endothelium tissues, yet greatly decreased in tissue with pathogenically progressed guttata. Considering the mimicry between in vitro CST such as EMT and fibrosis, we investigated miR profiles in fresh corneal endothelium tissues. Scatter plots of miR expression profiles between tissues with normal ECDs with those of ECD378 clearly demonstrated more upregulation of the miR-378 family in corneal endothelium than in corneal epithelium tissues, but a dramatic decrease in low ECD tissues accompanied with advanced guttata. To the contrary, miR146b-5p of which expression level was far higher than miR-378 family, was not reduced. qRT-PCR also showed that the expression of miR-378 family (a-3p, e and f) were uniformly depressed in tissues with ECD 795 and 1410, whereas miRs 200c, 205, and 124-5p were upregulated.
Conclusions :
The findings presented here warrant further investigation to better elucidate the role of dysregulated expression of miRs in the pathogenesis of BK and FECD.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.