PRL and cancer: KEGG pathway enrichment analysis of the DEPs showed that multiple cancer-related pathways were highly enriched, including the signaling pathways of PI3K-AKT, mitogen-activated protein kinase (MAPK), Rap1, insulin, forkhead box O (FoxO), ErbB, gonadotropin-releasing hormone (GnRH), T cell receptor, hypoxia-inducible factor-1 (HIF-1), prolactin, estrogen, VEGF, and mammalian TOR (mTOR) (Figure 8(a), Table S6).