ESR1 and cancer: Function analysis showed eight significant KEGG pathways were enriched, including hsa04015:Rap1 signaling pathway (PIK3R1), hsa05200:Pathways in cancer (PIK3R1, FOXO1), hsa05205:Proteoglycans in cancer (ESR1, PIK3R1), hsa04014:Ras signaling pathway (PIK3R1), hsa05218:Melanoma (PIK3R1) and hsa04520:Adherens junction (PTPRB) (Table 3).