Among all the ECM receptor genes that followed the expression pattern as shown in Fig. 4 C, ITGA5, a receptor of FN1 (Eble and Niland, 2019), was strongly correlated with macrophage abundance in multiple human PC bone metastasis datasets (Ylitalo et al., 2017; Haider et al., 2016; Fig. 5 A). The gene discussed is ITGA5; the disease is pachyonychia congenita.