Table 1 Drugs targeting ERS to treat breast cancer

Targeting IRE1α-XBP1 signaling

 MKC8866

Selective IRE1 RNase inhibitor

MYC-driven BC apoptosis

[42]

 STF083010

XBP1 splicing inhibitor

Improve tamoxifen sensitivity

[57]

 Doxorubicin

IRE1α-XBP1 inhibitor

Cell apoptosis

[53]

 Palmitate

IRE1-mediated XBP1 splicing activator

Improve trastuzumab sensitivity in HER2+ BC

[96]

Targeting PERK-elF2α-ATF4 signaling

 GSK2606414

PERK inhibitor

Improve radiotherapy sensitivity

[62]

 Oleandrin

p-PERK activator

Trigger immunogenic cell death (ICD)

[63]

 DHT

p-PERK activator

Cell apoptosis

[64]

 BHPI

Persistent ERα- dependent PERK activator

Endocrine-resistant BC apoptosis and necrosis

[65]

 Dandelion extract

p-PERK activator

TNBC cell apoptosis

[97]

 Ilamycin E

Trigger CHOP/Bcl-2

TNBC cell apoptosis

[50]

 TMAO

PERK activator

Promote immunotherapy in TNBC

[95]

 AMC-04

Activate ATF4/CHOP/DR5

Cell apoptosis

[66]

 ATA

PERK activator

HER2 + BC cell apoptosis

[98]

 ISRIB

eIF2α inhibitor

Prevent breast cancer cells with stem-cell-like features (BCSC)

[69]

Targeting GRP78

 HHQ-4

GRP78 inhibitor

Glucose-deprived BC cells apoptosis

[74]

 Plumbagin

GRP78 inhibitor

Improve tamoxifen sensitivity

[75]

 Kaempferol

GRP78 inhibitor

Cell apoptosis

[76]

 Epigallocatechin gallate

GRP78 inhibitor

Improve taxol and vinblastine sensitivity

[91]

 JI017

GRP78 activator

Improve paclitaxel sensitivity

[77]

 Betulinic acid

GRP78 activator

Improve taxol sensitivity

[92]

 Prodigiosin

GRP78 activator

Cell apoptosis

[78]

 Tunicamycin

GRP78 activator

Cell apoptosis

[79]

 Panobinostat

GRP78 hyperacetylation

Cell apoptosis

[80]

Targeting other pathways

 Melatonin

Promote ROS

Improve lapatinib sensitivity in HER2+ BC cells

[81]

 DK143

Promote ROS

Cell apoptosis

[82]

 ErSO

Open IP3R calcium channels

Induce rapid and selective necrosis of ERα+ BC

[83]

 MPPa-PDT

Induce autophagy

Cell apoptosis

[84]