KRT7 and pachyonychia congenita: Finally, four CIC-related genes significantly contributing to OS in PC patients were confirmed (Fig. 1G), and the risk score of each patient was calculated using the following formula: Risk score = (0.362 × expression level of KRT7) + [0.302 × expression level of AURKA (Aurora Kinase A)] + [− 0.114 × expression level of CDKN2A (Cyclin Dependent Kinase Inhibitor 2A)] + [− 0.377 × expression level of RARB (Retinoic Acid Receptor Beta)].