Fig. 2
From: Endoplasmic reticulum stress targeted therapy for breast cancer
UPR Signaling in ERα+ BC. In ERα+ BC cells, ERα can open IP3R calcium channels through PLCγ activity and then induce rapid anticipatory activation of the UPR. The IRE1α-XBP1s pathway is activated to reestablish ER homeostasis. PERK-eIF2α-ATF4 can be activated to induce expression of apoptosis genes, such as CHOP. PERK can also be activated to promote apoptosis through TNFα expression promoted by NF-κB. The drugs targeting ERS-associated signaling pathways in ER+ BC are listed. Red represents pathway inhibitors and green represents pathway activators