We also observed differential expression of CXCL5 and its receptor CXCR2 in normal penile tissues (NPT1, NPT2) and a panel of PC cell lines (Penl1, Penl2, 149RCa, LM156) (Figure 5B and Supplementary Figure S1A). Here, CXCR2 is linked to pachyonychia congenita.