Table 1.

miRNAs regulating anti-hormonal drug resistance in breast cancer

miRNA	Expression and effecta	Treatment	Target genes	Reference
Modulating ER signaling
miR-335	↓R	tamoxifen	ESR1	Martin et al.25
miR-342	↓R	tamoxifen	ESR1	He et al.26 and Young et al.27
Let-7b/i	↓R	tamoxifen	ESR1	Zhao et al.28
miR-181a-5p	↑R	tamoxifen	ESR1	Andreeva et al.29 and Benedetti et al.30
miR-192-5p	↑R	tamoxifen	ESR1	Kim et al.31
miR-135a	↓R	tamoxifen	ESR1	Zhang et al.32
miR-27a	↓R	tamoxifen	ZBTB10	Ljepoja et al.33 and Li et al.34
miR-32-5p	↓R	tamoxifen	ESR1	Wang et al.35
miR-125a-3p	↓R	tamoxifen	CDK3	Zheng et al.36
miR-873	↓R	tamoxifen	CDK3	Cui et al.37 and Zhang et al.38
miR-10b	↑R	tamoxifen	HDAC4	Ahmad et al.39
miR-330-3p	↑R	tamoxifen	HDAC4	Zhang et al.40
miR-22	↑R	fulvestrant	HDAC4, FOXP1	Wang et al.41
miR-320a	↓R	tamoxifen	ESRRA, PPP1R1B	Lü et al.42
miR-192-5p	↑R	tamoxifen	ESRRA	Kim et al.31
miR-135a1	↓R	tamoxifen	ESRRA, NCOA1	Zhang et al.32
miR-27b-3p	↓R	tamoxifen	NR5A2, CREB1	Zhu et al.43
miR-484	↓R	tamoxifen	KLF4	Wei et al.44
miR-375	↓R	tamoxifen	MTDH	Fu et al.45 and Ward et al.46
miR-486-5p	↓R	tamoxifen	HMGA1	Mansoori et al.47
Activation of signaling pathways
miR-26a/b	↓R	tamoxifen	ERBB2	Tan et al.48
miR-186-3p	↓R	tamoxifen	EREG	He et al.49
miR-21	↑S	tamoxifen, fulvestrant	PTEN	Yu et al.50
miR-489	↓R	tamoxifen	MAPK14, PTPN11	Soni et al.51
miR-214	↓S	tamoxifen, fulvestrant	UCP2	Yu et al.52
miR-195, miR-497	↓R	tamoxifen	MAP2K1, RAF1, AKT3	Tian et al.53
miR-519a	↑R	tamoxifen	PTEN	Ward et al.54
miR-190	↑S	tamoxifen	SOX9	Yu et al.55
miR-155	↑R	tamoxifen	SOCS6	Shen et al.56
miR-125b	↑R	aromatase inhibitors	GSK3β, p70S6K	Vilquin et al.57
Cell-cycle modulation
miR-221/222	↑R	tamoxifen	CDKN1B	Miller et al.58 and Wei et al.59
miR-575	↑R	tamoxifen	CDKN1B	Liu et al.60
miR-195, miR-497	↓R	tamoxifen	CCND1	Tian et al.53
miR-206	↓R	tamoxifen	WBP2	Tian et al.61
miR-519a	↑R	tamoxifen	CDKN1A, RB1	Ward et al.54
miR-339-5p	↓R	tamoxifen	CDK2	Feng et al.62
miR-15a/16	↓R	tamoxifen	CCNE	Chu et al.63
Other mechanisms
miR-26a	↓R	tamoxifen	E2F7	Liu et al.64
miR-15a/16	↓R	tamoxifen	BCL2	Cittelly et al.65
miR-195, miR-497	↓R	tamoxifen	BCL2	Tian et al.53
miR-375	↓R	tamoxifen	HOX3B	Fu et al.45 and Ward et al.46
miR-200b/c	↓R	tamoxifen	MYB	Gao et al.66
miR-19a-3p	↑S	letrozole	CYP19A1	Xiang et al.67
miR-27b	↓R	tamoxifen	HMGB3	Li et al.68
miR-500a-3p	↓R	tamoxifen	LY6K	Kim et al.31
miR-449a	↓R	tamoxifen	ADAM22	Li et al.69
miR-148a/miR-152	↓R	tamoxifen	ALCAM	Chen et al.70
miR-574	↓S	tamoxifen	CLTC	Ujihira et al.71
miR-145-5p, miR-424-5p	↓R	tamoxifen	PSAT1	Petri et al.72
miR-34b-5p, miR-876-5p	↓R	tamoxifen	PHGDH	Petri et al.72
miR-143	↓R	aromatase inhibitors	HK2	Bacci et al.73
miR-575	↑R	tamoxifen	BRCA1	Liu et al.60
miR-663b	↑R	tamoxifen	TP73	Jiang et al.74
miR-342	↓R	tamoxifen	GEMIN4, BMP-7	Cittelly et al.75

^aDown arrow (↓) represents decreased expression and up arrow (↑) represents increased expression of the miRNA; S indicates change of expression sensitizes breast cancer cells to endocrine therapy and R induces resistance in breast cancer cells.¹¹