A Network Biology Framework for Exploring Molecular Mechanisms in Cystoid Macular Edema

To explore the molecular mechanisms underlying cystoid macular edema (CME) through protein-protein interaction (PPI) network analysis, identifying key regulatory proteins, functional modules, and enriched biological pathways relevant to its pathogenesis.

A curated list of 18 CME-associated human proteins was compiled through a literature review, including inflammatory cytokines, angiogenic factors, and regulators of vascular permeability. High-confidence PPI data were obtained from the STRING database (confidence score ≥ 0.700) and visualized as an undirected graph using NetworkX in Python. Centrality metrics (degree, betweenness, closeness, eigenvector), Louvain modularity analysis, and functional enrichment (GO: BP, KEGG, Reactome) were performed using GSEAPY and Enrichr to identify topologically and biologically important nodes and clusters.

The final network consisted of 91 nodes and 217 edges, with a graph density of 0.0505 and an average clustering coefficient of 0.0554. ANGPT2, FLT1, KDR, TNF, and VEGFA appeared as central hub proteins across multiple centrality measures. Louvain clustering identified eight distinct functional communities, including inflammatory mediators, angiogenic signaling components, and tight junction regulators. Enrichment analyses showed significant involvement of cytokine-mediated signaling, endothelial cell migration, the AGE-RAGE pathway, TNF signaling, and interleukin-4/10/13 signaling, highlighting the dual roles of angiogenesis and inflammation in CME.

The findings of this study highlight the intricate network of molecular mechanisms underlying cystoid macular edema (CME), with particular emphasis on angiogenesis, inflammation, and vascular permeability. The identification of key regulatory proteins such as ANGPT2, FLT1, and TNF underscores the complexity of CME pathogenesis, which involves both vascular and inflammatory pathways.

CME is driven by a complex, modular molecular network involving inflammation, vascular remodeling, and cytokine signaling. ANGPT2, FLT1, TNF, and IL6 are key regulatory proteins and potential therapeutic targets. This systems biology approach offers a comprehensive framework for discovering new insights and guiding personalized treatment strategies in CME.