TABLE 2.

miRNAs regulated in breast cancer¹

miRNA	Up-/Downregulation	Functions	Target genes	References
Let-7	Down	Inhibits proliferation and metastasis	HMGA2, H-RAS, K-RAS, c-MYC, CCND2, PBX3	57
miR-1	Down	Inhibits proliferation and migration	FRIZZLED 7, TANKYRASE 2	58
miR-7	Down	Promotes drug sensitivity	MRP2	59
miR-9a	Up	Promotes metastasis	CDH1	57
miR-10a	Down	Inhibits proliferation	RARβ, THRα	60
miR-10b	Up	Promotes migration, invasion, and metastasis	HOXD10, SYNDECAN 1	57
miR-15a	Down	Inhibits metastasis and induces apoptosis	BCL-2, E2F	57
miR-15b	Up	Promotes migration	MTSS1	61
miR-16a	Down	Inhibits metastasis and induces apoptosis	WIP1, BCL-2, E2F, CDK6, CCND1	57
miR-17–5p	Down	Inhibits proliferation	AIB1	62
miR-19a-3p	Down	Inhibits proliferation, metastasis, and angiogenesis	FRA1, STAT3, VEGF	57
miR-20a/b	Up	Promotes proliferation, angiogenesis, and metastasis	CCND1, PTEN, HIF-1α	57, 63
miR-21	Up	Promotes proliferation, metastasis, and EMT	PDCD4, PTEN, CDC25, MSH2, MESPIN	57
miR-22	Down	Inhibits metastasis	CDK6, SIRT1, SP1	57
miR-26a	Down	Inhibits proliferation and metastasis	GREB1, MTDH, CCND2, CCNE2	57
miR-27a	Up	Promotes cell viability and cell cycle	ZBTB4, ST4, MYT1, FOXO1	64
miR-29b	Down	Inhibits metastasis and angiogenesis	ITGβ1, MMP2, TIAM1	65
miR-30a	Down	Inhibits proliferation and metastasis	MTDH	66
miR-30c	Down	Promotes drug sensitivity	TWF1, IL-11	67, 68
miR-31	Down	Promotes drug sensitivity and inhibits metastasis	RHOA, RADIXIN, IGA5, PRKCE	65, 69
miR-34(a,b,c)	Down	Induces apoptosis and inhibits proliferation	CCND1, FRA1, c-MYC, NOTCH 1, EYA2, CDK4/6, CCND1, SIRT1, AXL	57
miR-93	Up	Promotes angiogenesis and metastasis	LATS2	70
miR-96	Up	Promotes cell viability and cell cycle	FOXO1	64
miR-103/107	Up	Promotes migration and global miRNA biogenesis	DICER, DAPK4, KLF4	71
miR-106b	Up	Promotes invasion and metastasis	p21, AIB1, pRB, BRMS1, CDKN1A	72, 73
miR-124	Down	Inhibits metastasis	SLUG, EZH2, ROCK2, CDK4	57
miR-125a-5p	Down	Inhibits proliferation	HDAC4/5, HER3, HUR	57
miR-125b	Down	Inhibits cell proliferation, invasion, and metastasis	EPOR, ENPEP, CK-α, HER2	57
miR-126	Down	Inhibits cell proliferation, invasion, and metastasis	IGFBP2, PITPNC1, MERTK, VEGF	57
miR-128	Down	Inhibits self-renewal	BMI-1, ABCC5	74
miR-142	Up	Promotes self-renewal	APC	75
miR-142-3p	Down	Inhibits proliferation, invasion, and metastasis	WASL, ITGα, RAC1, COFLIN2	76
miR-143	Down	Inhibits proliferation and metastasis	HER3, DNMT3	57, 77
miR-145	Down	Inhibits proliferation, angiogenesis, and metastasis	EGFR, c-MYC, VEGF, N-CDH, HIF-2α, MUCIN 1, HER3, ROCK1	57
miR-146a/b	Down	Inhibits proliferation and metastasis	ICAM1, NF-κB, STAT3	57
miR-155	Up	Promotes proliferation, metastasis, and telomere length	RHOA, CXCR4, SOX1, p53, FOXO3	57
miR-181a	Up	Inhibits apoptosis	ATM	57
miR-181b-3p	Up	Promotes invasion and metastasis	SMAD3, YWHAG	78
miR-182	Up	Invasion and metastasis	BRCA1, FOXO1	57, 64
miR-185	Down	Inhibits proliferation	DNMT1	79
miR-194	Down	Inhibits metastasis	TALIN 2	57
miR-199b-5p	Down	Inhibits proliferation	HER2	57
miR-200a	Down	Inhibits migration	SLUG, BMI-1, ZEB1/2, EPH2	57, 80
miR-200b	Down	Inhibits cell proliferation and induces apoptosis	SP1	81
miR-200c	Down	Inhibits self-renewal and metastasis	BMI-1, ZEB1/2	57
miR-205	Down	Inhibits proliferation and metastasis	HER3, p53	57
miR-206	Down	Inhibits cell growth, metastasis, and drug sensitivity	ERα, CCND2	57
miR-216b	Down	Inhibits cell growth and metastasis	P2 × 7, SDCBP	57, 82
miR-221/222	Up	Promotes drug resistance and cell proliferation and is antiapoptotic	ERα, PTEN, p57, p27	57, 83
miR-301a	Up	Promotes proliferation and metastasis	PTEN	57
miR-326	Down	Promotes drug sensitivity	ABCC1	84
miR-328	Down	Promotes drug sensitivity	ABCG2	85
miR-335	Down	Induces apoptosis and inhibits metastasis	SOX4, TENASCIN c, SP1, BCL-2	57
miR-345	Down	Promotes drug sensitivity	MRP2	59
miR-339-5p	Down	Induces apoptosis	BCL-6	57
miR-342	Down	Inhibits proliferation	EGFR, HER2, AKT, PKC	57
miR-373/520c	Up	Promotes invasion and metastasis	CD44	57
miR-429	Down	Inhibits cell proliferation and metastasis	ZEB1, TUBB2A, CRKL	57
miR-451	Down	Promotes drug sensitivity	MDR1	86
miR-487a	Down	Promotes drug sensitivity	ABCG2	87
miR-489	Down	Promotes drug sensitivity	SMAD3	88
miR-491-5p	Down	Promotes proliferation	JMJD2B, EGFR, HER2	57, 89
miR-495	Up	Promotes proliferation and hypoxia resistance	CDH1, REDD1	90
miR-498	Down	Induces apoptosis and inhibits proliferation and metastasis	hTERT, HER2	13, 91
miR-708	Down	Inhibits metastasis	NEURONATIN	57
miR-888	Up	Promotes metastasis	CDH1, ACTγ1, CDC42	57

¹ABCC, ATP-binding cassette subfamily C member; ABCG2, ATP-binding cassette sub-family G member 2; ACTγ1, actin gamma 1; AIB1, amplified in breast cancer 1; AKT, protein kinase B; APC, activated protein C; ATM, ataxia-telangiectasia mutated; AXL, axillary lymphoscintigraphy; BCL, B-cell lymphoma; BMI-1, B lymphoma Moloney murine leukemia virus insertion region 1 homolog; BRCA1, breast cancer type 1 susceptibility protein; BRMS1, breast cancer metastasis-suppressor 1; CCND, cyclin D; CCNE2, G1/S-specific cyclin-E2; CDC, cell division cycle; CDH1, cadherin-1; CDK, cyclin-dependent kinase; CDKN1A, cyclin dependent kinase inhibitor 1A; CD44, cluster of differentiation 44; CK-α, cytokeratin-α c-MYC, avian myeloblastosis; CRKL, crk-like protein; CXCR4, C-X-C chemokine receptor type 4; DAPK4, death-associated protein kinase 4; DNMT, DNA (cytosine-5)-methyltransferase; EGFR, epidermal growth factor receptor; EMT, epithelial mesenchymal transition; ENPEP, glutamyl aminopeptidase; EPH2, erythropoietin-producing human hepatocellular receptors 2; EPOR, erythropoietin receptor; ERα, estrogen receptor alpha; EYA2, eyes absent 2; EZH2, enhancer of zeste homolog 2; FOX, forkhead box protein; FRA1, fos-related antigen-1; GREB1, gene regulated by estrogen in breast cancer-1; HDAC4/5, histone deacetylase 4/5; HER, human epidermal growth factor receptor; HIF, hypoxia-inducible factor; HMGA, high-mobility group AT-hook; HOXD10, homeobox 10; H-RAS, Harvey rat sarcoma; hTERT, human telomerase reverse transcriptase; HUR, human antigen R; ICAM1, intercellular adhesion molecule 1; IGA5, immunoglobulin A5; IGFBP2, insulin-like growth factor–binding protein 2; ITG, integrin; JMJD2B, jumonji domain-containing protein 2B; KLF4, kruppel-like factor 4; K-RAS, kirsten rat sarcoma; LATS2, large tumor suppressor kinase 2; MDR1, multidrug resistance protein 1; MERTK, c-Mer tyrosine kinase; miRNA, microRNA; MMP, matrix metalloproteinase; MRP2, multidrug resistance protein; MSH2, mutS protein homolog 2; MTDH, metadherin; MTSS1, metastasis suppressor 1; MYT1, myelin transcription factor 1; N-CDH, N-Cadherin; P2 × 7, P2 × purinoceptor 7; PBX3, pre B cell leukemia transcription factor 3; PDCD4, programmed cell death 4; PITPNC1, phosphatidylinositol transfer protein cytoplasmic 1; PKC, protein kinase C; pRB, retinoblastoma protein; PRKCE, protein kinase C epsilon; PTEN, phosphatase and tensin homolog; RAC1, ras-related C3 botulinum toxin substrate 1; RARβ, retinoic acid receptor β REDD1, regulated in development and DNA damage response 1; RHOA, ras homolog gene family, member A; ROCK, ρ-associated protein kinase; SDCBP, syndecan binding protein; SIRT1, Sirtuin1; SMAD3, mothers against decapentaplegic homolog 3; SOX, sex determining region Y box; SP, specificity protein; STAT3, signal transducer and activator of transcription 3; ST4, suppression of tumorigenicity 4; THRα, thyroid hormone receptor α TIAM1, T-lymphoma invasion and metastasis 1; TUBB2A, tubulin beta-2A; TWF1, twinfilin actin-binding protein homolog 1; VEGF, vascular endothelial growth factor; WASL, Wiskott-Aldrich syndrome-like; WIP1, wt-p53-induced phosphatase; YWHAG, tyrosine 3-monooxygenase/tryptophan 5-monooxygenase; ZBTB4, zinc finger BTB broad complex/tramtrack/bric-a-brac domain protein 4; ZEB1/2, zinc finger E-box-binding homeobox 1/2.