Differential expression analysis by gene array of cell cycle modulators in human corneal epithelial cells stimulated with epidermal growth factor (EGF), hepatocyte growth factor (HGF), or keratinocyte growth factor (KGF).
OBJECTIVE
To identify and differentiate cell cycle and differentiation genes that are up-regulated or down-regulated in human corneal epithelial cells in response to alternative epithelium-modulating cytokines epidermal growth factor (EGF), hepatocyte growth factor (HGF) or keratinocyte growth factor (KGF).


METHODS
Primary cultures human corneal epithelial cell (HCE) were treated with 25 ng/ml of EGF, 25 ng/ml HGF, 25 ng/ml KGF, or vehicle for 8 hours. Complementary DNA (cDNA) probes were synthesized from total cellular RNA isolated from the HCE cells. The cDNA probes were hybridized to the Atlas human cell cycle/differentiation array membrane. RNAse protection assay was used to confirm up-regulation of the serine/threonine-protein kinase PITALRE gene by EGF, KGF, and HGF.


RESULTS
The expression of one hundred and eleven cell cycle and differentiation genes was monitored with the gene array system. It was found that these epithelial cell-modulating cytokines shared similar effects on some of the cell cycle and differentiation genes that were monitored, but had specific effects on some cytokines. Up-regulation of PITALRE gene expression was confirmed using RNAse protection assay.


CONCLUSIONS
EGF, HGF and KGF had differential effects on cell cycle- and differentiation-related gene expression in corneal epithelial cells. For example, all three mitogenic growth factors up-regulated the expression of cyclin D1 (BCL-1 oncogene) and serine/threonine-protein kinase PITALRE in the primary cultured human corneal epithelial cells. However, EGF and KGF, but not HGF, up-regulated expression of the E2F-1 pRB-binding protein gene. Thus, while these three epithelial mitogens have similar effects on many genes that were analyzed, important differences were noted that may relate to differing effects of these growth factors on corneal epithelial cells. Studies to analyze the significance of the identified differences among these growth factors are in progress.
Lee
J S
JS
Department of Ophthalmology, University of Washington, School of Medicine, Seattle 98195-6485, USA.
Liu
J J
JJ
Hong
J W
JW
Wilson
S E
SE
D002453:Cell Cycle / Q000502:physiology*; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism*; D002454:Cell Differentiation; D002478:Cells, Cultured; D019938:Cyclin D1 / Q000378:metabolism; D042863:Cyclin-Dependent Kinase 9; D018844:Cyclin-Dependent Kinases / Q000378:metabolism; D015342:DNA Probes; D004268:DNA-Binding Proteins; D050684:E2F Transcription Factors; D050687:E2F1 Transcription Factor; D004815:Epidermal Growth Factor / Q000494:pharmacology*; D019573:Epithelium, Corneal / Q000187:drug effects* / Q000378:metabolism; D051523:Fibroblast Growth Factor 7; D005346:Fibroblast Growth Factors / Q000494:pharmacology*; D020869:Gene Expression Profiling; D017228:Hepatocyte Growth Factor / Q000494:pharmacology*; D006801:Humans; D020411:Oligonucleotide Array Sequence Analysis; D014157:Transcription Factors / Q000378:metabolism; D015854:Up-Regulation
D018797:Cell Cycle Proteins; D015342:DNA Probes; D004268:DNA-Binding Proteins; D050684:E2F Transcription Factors; D050687:E2F1 Transcription Factor; C493753:E2F1 protein, human; C496453:FGF7 protein, human; D014157:Transcription Factors; D051523:Fibroblast Growth Factor 7; D019938:Cyclin D1; D005346:Fibroblast Growth Factors; D004815:Epidermal Growth Factor; D017228:Hepatocyte Growth Factor; C467969:CDK9 protein, human; D042863:Cyclin-Dependent Kinase 9; D018844:Cyclin-Dependent Kinases