Trinh HKT, et al. - The role of folliculin (FLCN) in the pathogenic mechanisms of aspirin-exacerbated respiratory disease (AERD) was investigated via analyzing 178 subjects with AERD, 276 subjects with aspirin-tolerant asthma (ATA) and 71 normal healthy controls (NC) at Ajou Medical Center. Subjects in AERD group had significantly higher serum FLCN levels than those in ATA and NC groups. Researchers used the cutoff value of 56.6 pg/mL to define the high FLCN phenotype (highFLCN). Asthmatic patients with highFLCN were associated with increased airway hyperresponsiveness to methacholine. Findings suggest an increase of FLCN release from human airway epithelial cells (HAECs) in relation to high leukotrienes (LT) and airway eosinophilia, this enhances epithelial activation and disruption. For AERD, modulation of FLCN could be a potential target.