AIM: To investigate the changes of protein expressions in human lens epithelial cells(SRA01/04)undergoing oxidative damage, hoping to provide new protein target for the pathogenesis of age-related cataract(ARC).

METHODS: SRA01/04 cells were divided into experimental group and control group. In the experimental group, cells were irradiated with ultraviolet-B(UVB)for 10min to establish the model of oxidative damage, whereas cells in the control group were untreated. Protein expression profile from the two groups was sequenced by isobaric tags for relative and absolute quantitation(iTRAQ). The filtering criteria that fold change >1.2 and p<0.05 was used to determine the differentially expressed proteins(DEPs). Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)database were utilized for functional enrichment analysis of the top 50 DEPs with either up-regulated or down-regulated significance. Furthermore, Pathway commons software was used to establish the protein-protein interaction(PPI)network.

RESULTS: Overall, 552 DEPs were screened out. A total of 176 DEPs were up-regulated in the experimental group compared with the control group, including HMGB1 and USP1, while 376 DEPs were down-regulated, including POLR2A and POLR2B. GO and KEGG enrichment analysis indicated that the top 50 DEPs with up-regulated or down-regulated significance were involved in various crucial biological processes and signaling pathways. PPI network revealed that oxidative damage repair(ODR)-related proteins might play a key role in UVB-induced oxidative damage.

CONCLUSIONS: The expressions of multiple proteins, especially ODR-related proteins, can be altered in SRA01/04 cells via UVB irradiation. These findings may provide cellular-related insights into the pathogenesis of ARC and into proteins or pathways associated with therapeutic targets.