As type I collagen is one of the main components in the TME (14, 15, 16, 17), we focused on studying the functional interplay between GLI2 and COL1A1. In our patient cohort, we found higher levels for COL1A1 and GLI2 in PC in comparison to healthy and pancreatic intraepithelial neoplasia tissues (Fig. 2, B and C) and a positive correlation between GLI2 and COL1A1 in tumors (Fig. 2D). This evidence concerns the gene COL1A1 and pachyonychia congenita.