In the same way, CXCL12/CXCR4 (C-X-C motif chemokine ligand 12/C-X-C motif chemokine receptor 4) signaling axis can confer drug resistance to PC cells and participate in the invasion and metastasis of PC 332, 333. The gene discussed is CXCR4; the disease is pachyonychia congenita.