ESR1 and cancer: Above findings indicated ALB, EGFR, ESR1, AR, PGR, and HSP90AA1 to be located at a key position and majorly involved in pathways related to cancer (has05200), PI3K–Akt signaling pathway (has04151), estrogen signaling pathways (hsa04915), breast cancer (hsa05224), EGFR tyrosine kinase inhibitor resistance (hsa01521), proteoglycans in cancer (hsa05205), and Ras signaling pathway (hsa04014), thereby suggesting their implication in regulating the occurrence and development of BC.