Transcriptomic Features of Recurrence Rates in Idiopathic Subglottic Stenosis

Abstract

Objective: Idiopathic subglottic stenosis (iSGS) is a rare disease characterized by narrowing of the upper airway and affects near-exclusively females. Patients often experience recurrent disease and require repeated surgical dilations. The pathophysiology underlying the broad spectrum of disease severity within iSGS remains unknown. In the current study, we sought to identify transcriptomic differences between iSGS patients with markedly different recurrence rates.

Methods: Prospectively collected clinical and bulk RNA sequencing data from subglottic tissues of 56 female iSGS patients with 1-4 years of follow-up were analyzed. DESeq2 was used to perform differential expression analysis, comparing samples from the highest (1.19-1.87 dilations/year) versus the lowest (0.30-0.65 dilations/year) quartile of surgical dilation rate (i.e., high vs. low recurrence groups).

Results: In total, 220 genes were significantly differentially expressed between the high and low recurrence groups (adjusted p < 0.1 and log₂ fold change > |1|). Pathway enrichment analyses showed that the high recurrence group had significantly increased expression of genes involved in adaptive immune responses (e.g., immunoglobulin subunit genes) and extracellular matrix organization (e.g., COMP, NID2) (adjusted p < 0.1). In contrast, the low recurrence group had significantly increased expression of genes involved in cilia structure and function (e.g., CFAP43, DNAI2) (adjusted p < 0.1), suggesting a relatively increased abundance of respiratory cilia.

Conclusion: Transcriptomic profiling suggests that lower recurrence rates in iSGS are associated with retention of respiratory cilia, while adaptive immune responses and increased extracellular matrix deposition are present in those with higher recurrence rates. These results hold promise for the development of prognostic markers and identification of therapeutic targets for iSGS.

Keywords: B cell; RNA sequencing; adaptive immunity; extracellular matrix; fibrosis; idiopathic subglottic stenosis (iSGS); surgical endoscopic dilation.

FIGURE 1

Volcano plot of differential gene expression analysis comparing subglottic tissue samples from patients with idiopathic subglottic stenosis (iSGS) in the high vs. low recurrence groups. Color indicates genes that had significantly higher expression in the high recurrence group (purple) or in the low recurrence group (orange). The dashed lines indicate the differential gene expression cut‐offs for log₂ fold change > |1| (vertical) and adjusted p < 0.1 (horizontal). See Table S3 for the full list of genes tested for differential expression. [Color figure can be viewed in the online issue, which is available at www.laryngoscope.com.]

FIGURE 2

Dotplots (left) and enrichment maps (right) showing gene sets that contain an overrepresentation of genes with significantly higher expression in (A) the high recurrence group and (B) the low recurrence group. The top 15 gene sets, ranked by gene ratio, are shown for each group. Enrichment map connectivity (gray lines) is based on the number of overlapping genes between gene sets (nodes). See Tables S4 and S5 for the full list of gene sets and the genes they contain. [Color figure can be viewed in the online issue, which is available at www.laryngoscope.com.]