ESR1 and breast cancer: On the other hand, the tumor-vs-NAT module (Hub 2) encapsulates canonical epithelial breast-cancer programs: steroid signaling and chaperone dependence (ESR1, HSP90AA1) [49], integrin/tetraspanin-organized adhesion and invasion (ITGA5 with CD151/TM4SF5 neighborhood) [25], stemness and therapy tolerance (PROM1/CD133) [50], and transporter/secretome remodeling (ABCC8, PATE-family/LY6 cluster).