Table 1.

Expression of miRNAs in Breast Cancer and their Targets

miRNA	Expression in Breast Cancer Subtypes	Activity	Targets
let-7 family	↑L, ↑Her2−, ↓NL	TS	Ras[142], HMGA2[144]
miR-9	↑ER+, ↓Her2+	Pro-metastatic	CDH1[101]
miR-10a/b	↑L, ↓M, ↑Her2−	OG/Pro-metastatic	HOXD10[103], Tiam1[104]
miR-17-5p	↑B, ↑NL	TS	AIB1[88]
miR-15/16	↓NL		BCL2[153], CCND1[154]
miR-21	↑ER+, ↓Her2+	OG/Pro-metastatic	PTEN[71], TPM1[74], PDCD4[72], Maspin[73], BCL2[140], p63[75], HNRPK[75]
miR-22	↓ER+		ERα[51]
miR-26a/b	↑PR+, ↑ER+
miR-29b	↓L, ↑Her2+	TS	MCL1[155], TCL1[156], DNMT3[157], p85α[94], CDC42[94]
miR-30a-5p, -30b, -30c, -30d	↑PR+, ↑ER+
miR-31		Anti-metastatic	Fzd3, ITGA5, MMP16, M-RIP, RDX and RhoA[110]
miR-107	↑Her2−		CDK6[158]
miR-125a/b	↓Her2+	Anti-metastatic/TS	HER2 and HER3[78]
miR-126	↓L, ↑Her2−	TS	IRS-1[107], p85β[159]
miR-130a	↓NL, ↓Her2+		GAX and HOXA5[160]
miR-143	↑Her2−	TS	Raf1[161], ERK5[162]
miR-145	↓B, ↓L, ↑Her2−	Anti-metastatic/TS	Raf1[161], ERK5[162]
miR-146a/b	↑NL	Anti-metastatic	EGFR[163], CXCR4[164], IRAK1[165], KIT[166], TRAF5[165], IL8 and IL6[108], MMP-9[108]
miR-150	↑ER+, ↓Her2+		c-Myb[167]
miR-154	↑Her2−
miR-182		Pro-metastatic	FOXO3 and MITF[168]
miR-185	↓ER+		AKT1, CDK6 and HMGA2[158]
miR-191	↑ER+
miR-195	↑Her2−
miR-200 family	↓M, ↑ER+	Anti-metastatic/TS	TCF8/ZEB1 and ZEB2[60–62], BMI1[37], TUBB3[100], SOX2 and Klf4[65]
miR-205	↓M, ↑ER+, ↓Her2+		HER3[80], E2F and PKCε[169], PTEN[35], ZEB1 and ZEB2[60]
miR-206	↓ER+, ↑NL	Anti-metastatic/TS	ERα[46]
miR-210	↑ER+,	Pro-metastatic	EFNA3, E2F3, NPTX1, RAD52, and ACRVB1[170] RAD23B[117], EFNA3[120], ISCU1/2[121]
miR-212	↓ER+		ZO-1[171]
miR-214	↓L		PTEN[172]
miR-221/222	↑Her2+		FOXO3 and ERα[49]
miR-335		Anti-metastatic/TS	SOX4, PTPRN2, MERTK, and TNC[106]
miR-373	↑M	Pro-metastatic/OG	CD44[111], RAD23B[117], LATS2[173]
miR-520c		Pro-metastatic	CD44[111]

NL=Normal like, L=luminal, B=Basal, M=Metastatic disease, TS=Tumor Suppressor, OG=Oncogenic