COL1A1 and plexiform neurofibroma: In an analysis of the matrisome of human cNFs using single-cell RNA sequencing, Brosseau et al. highlighted the low expression of type I (COL1A1 and COL1A2) and type XI (COL11A1) collagens in cNFs, whereas type VI collagen (COL6A1, COL6A2, COL6A3) was abundantly expressed by neurofibroma fibroblasts [35].