AKT1 and breast cancer: In fact, it has been proven that the upregulation of PI3K‐AKT‐mTOR signaling is associated with the endocrine resistance of breast cancer.[3, 27] Consistently, deficiency of STING signaling in parental MCF7 and ZR75.1 cells enhanced the phosphorylation of AKT1 and GSK3β (Figure 6C), indicating activation of PI3K‐AKT signaling.