MTOR and breast cancer: As activation of the PI3K/mTOR/mTOR signaling pathway is very common in patients with breast cancer [95], and western blot analysis has revealed that the main signaling molecules of this pathway are positively correlated with HIF-2α expression, HIF-2α may also maintain the stemness of human breast cancer CSCs through the PI3K/AKT/mTOR signaling pathway [96].