ObjectiveTo characterize proteomic profile in aqueous humor of patients with pathologic myopia (PM) using quantitative proteomic analysis, which may provide new clues to understand the mechanisms and possible treatments of PM.MethodsA cross-sectional study. From January 2019 to August 2019, aqueous humor samples (32 cataract patients) were collected for quantitative proteomic analysis using liquid chromatography tandem mass spectrometry at Tianjin Medical University Eye Hospital. There were 11 males and 21 females. They were 58-76 years old with an average age of 68.41±6.09 years old. Sixteen patients with PM were regarded as PM group, 16 patients without myopia were regarded as the control group. The aqueous humor samples (100-150 μl ) were collected from all patients before cataract surgery. Using protein quantification and non-labeled liquid chromatography tandem mass spectrometry analysis, differentially expressed proteins were obtained. Five different proteins were randomly selected for ELISA verification. The differentially expressed proteins were further analyzed by gene ontology enrichment and Kyoto Encyclopedia of Genes and Genomes, which were validated using ELISA in the other twenty samples of each group.ResultsA total of 583 proteins were identified and 101 proteins were found to be differentially expressed, including 63 up-regulated proteins and 38 down-regulated proteins. ELISA verification results showed that the expression trend of the 5 differentially expressed proteins between the PM group and the control group was consistent with the results of Label-free quantitative proteomics analysis. The main classifications of these differentially expressed proteins were protein-binding activity modulator, defense/immunity protein, protein modifying enzyme, metabolite interconversion enzyme, extracellular matrix protein, transfer/carrier protein and so on. The bioinformatics analysis suggested that PM was closely associated with inflammation and immune interactions, and remodeling of extracellular matrix.ConclusionsCompared with the control group, the protein expression profile of PM patients' aqueous humor specimens has obvious changes. These differences indicate that PM is closely related to inflammation and immune interaction and extracellular matrix remodeling.