Table 7.

Predictive microRNAs - microRNAs involved in response (sensitivity/resistance) to conventional breast cancer therapeutic strategies

Therapy	Generic name	miRNA	Role in response a	Evidence	Number of patients or type of cells	Reference
Hormone therapy
SERM	Tamoxifen	miR-375	Sensitivity	Preclinical/clinical	2 BC datasets	[80]
		miR-342	Sensitivity	Preclinical	MCF-7	[74]
			Sensitivity	Clinical	n = 791	[81]
		miR-221/222	Resistance	Preclinical	MCF-7, T47D, MM-468	[82-84]
SERD	Fulvestrant	miR-221/222	Resistance	Preclinical	MCF-7	[85]
AI	Letrozole	let-7f	Sensitivity	Preclinical/clinical	n = 23	[86]
Targeted therapy
Monoclonal AB	Trastuzumab	miR-210	Resistance	Preclinical/clinical	n = 43	[87]
Chemotherapy
	FEC	miR-125b	Resistance	Preclinical/clinical	n = 56	[89]
			Resistance	Preclinical	MM-435, SKBR3	[88]
			Resistance	Clinical	n = 185	[90]
	Taxol/doxo	miR-30c	Sensitivity	Preclinical	T47D, MCF-7, MM-231	[91,92]
	Taxol	miR-21	Resistance	Preclinical	MM-468	[9,93]
Radiotherapy
	Radiotherapy	miR-34a	Sensitivity	Preclinical	T47D, MCF-7, MM-231	[95,96]

^aMicroRNA (miRNA) overexpression leads to an increase in resistance or sensitivity to the mentioned therapy (referred to as ‘resistance’ or ‘sensitivity’, respectively). AB, antibody; AI, aromatase inhibitor; BC, breast cancer; Doxo, doxorubicin; FEC, fluorouracil, epirubucin and cyclophosphamide; SERD, selective estrogen receptor downregulator; SERM, selective estrogen receptor modulator; Taxol, paclitaxel.