ESR1 and cancer: However, a few proteins (ERBB2, IRS1, Integrins, GSK3B etc.)in this list are known to participate in several cancer related pathways such as ERBB signalling, Insulin signalling, Angiogenesis pathway, Ras pathway etc. A transcriptional module involving ESR1 and its known targets was also identified among these proteins (Supplementary data 4).