SPP1 and pachyonychia congenita: Nine prognosis-specific IRGs were identified by a series of bioinformatics analysis: S100A2, AREG, CXCL10, MET, OAS1, PI3, PLAU, S100A14, and SPP1. Among them, AREG, CXCL10, MET, PLAU, S100A14, and SPP1 have been reported to be involved in the carcinogenesis and progression of PC (43–48), implying that our risk signature has considerable prognostic value.