In a further study of patients’ PC tissues, we found that the positive rates of PELI1 and Ki-67, a proliferation-related indicator, were higher in PC tissues than in the paracancerous samples, and there was a positive correlation between the expression of PELI1 and the positive rate of Ki67 in PC tissues (Fig. S2D). This evidence concerns the gene PELI1 and pachyonychia congenita.