KEGG pathway analyses were conducted (Fig. 7E-G), and it is noteworthy that the genes co-expressed with C3 were remarkably enriched in IL-17 signaling, TNF signaing, and NF-κB signaling pathways; the genes co-expressed with FN1 were mainly enriched in protein processing in endoplasmic reticulum, which were all related to the occurrence and development of cancer. Here, TNF is linked to cancer.