Mechanistic Analysis of NHS Mutation in Congenital Cataract via Patient-Derived hiPSC Model

Purpose To clarify the functional role of Nance-Horan syndrome (NHS) gene in congenital cataract (CC) and its underlying pathogenic mechanism, focusing on lens epithelial cells (LECs) homeostasis. Methods NHS knockdown was performed in SRA01/04 human LECs, followed by transcriptomic, cytoskeletal, and functional analyses. Key downstream targets were validated via gain/loss-of-function assays. Urine-derived human induced pluripotent stem cells (hiPSCs) from an NHS-mutant CC patient were generated, and isogenic gene-corrected controls were established using CRISPR/Cas9. hiPSCs were differentiated into LECs for phenotypic validation. Results NHS depletion in SRA01/04 cells disrupted F-actin organization, reduced ZO-1 expression, impaired proliferation/migration, dysregulated cell cycle, and increased apoptosis. Transcriptomics identified enriched ECM-receptor interaction pathways, with integrin α2 (ITGA2) as a key downregulated gene. ITGA2 knockdown phenocopied NHS depletion, while NHS/ITGA2 overexpression partially rescued defects. NHS-mutant hiPSC-derived LECs exhibited cytoskeletal/junctional abnormalities, which were reversed in gene-corrected cells. Conclusions NHS regulates LEC homeostasis via ITGA2-mediated ECM-cytoskeleton signaling. This study establishes the first urine-derived hiPSC model of NHS-associated CC, providing mechanistic insights for targeted therapeutic development.