ISG15 and human papilloma virus infection: On the other hand, the downregulated genes (n = 157), such as ISG15, IRF7, OASL, OAS1, TNF, CDKN1A, CXCL8, E2F1, CXCL2, CTSL, and CCL4L2, were enriched in pathways related to bladder cancer, Nod-like receptor signaling, human papillomavirus infection, antigen processing and presentation, glycerophospholipid metabolism, and cytoplasmic DNA- sensing (Figure 2b).