Skin transcriptome analysis reveals potential molecular mechanisms of S100A9 in exacerbating the inflammation in rosacea

We have read with great interest the article by Le et al. (Le et.al., 2024) that previously reported S100A9 in exacerbating the inflammation in rosacea. Based on clinical investigation and experiments, this innovative work firstly found that S100A9 can aggravate the dermatitis through TLR4/MyD88/NF-κB pathway and may become a new target for treatment, which highlighted the critical role of S100A9 in the pathogenesis of rosacea. However, there still exist mysteries about whether S100A9 mediates the progression of inflammation via other molecular mechanism, and the interplay between S100A9 and other inflammatory mediators is also unclear. Through skin transcriptome analysis in a larger cohort, we noted that S100A9 may aggravate the inflammatory skin lesions in rosacea patients by cooperating with multiple immune cells and other inflammatory proteins, particularly those from the S100A family.