TABLE 2.

Role of exosomal miRNAs in breast cancer invasion, migration, and metastasis.

Exosomal miRNA	Parameters	Molecular targets	Mechanism	References
miR-21, miR-10b, miR-373, miR-1246, miR-17-5p, miR-96, and miR-106b	Promotes invasion and migration	PTEN, PI3K, mapsin, PDCD4, HODX10, TBX5, DYRK1A, Syndecan-1, CCNG2, CD44, HBP1, TCF, LEF, ErbB2, FUT6, and Wnt/β-Catenin	┬ Apoptosis, ┬ clone formation, ↑ Tumorigenesis, ↑ Migration, and regulates cytoskeleton and E-cadherin	Huang et al. (2008), Zhu et al. (2008), Li et al. (2011), Ibrahim et al. (2012), Chen et al. (2013), Eichelser et al. (2014), Singh et al. (2014), Feng and Tsao (2016), Hong et al. (2016), Kim et al. (2016), Li et al., 2016; Shi (2016), Li et al. (2017b), and Xu et al. (2019)
miR-564, miR-10a, miR-34c, miR-217, miR-1226-3p, miR-21, miR-19a-3p, miR-148b-3p, miR-19b, miR-1486-3p, miR-148a, miR-503, miR-17/20, and miR-100	Suppresses invasion and migration	Akt, GNA12, GYS1, SRF, PIK/MAPK, mTOR, GIT1, KLF5, FZD8, Wnt-β-Catenin, AQP5, FOSL1, mucin1, TRIM29, CCND2/CCND3, E2F1, IL-8, and CCND1	Arrest cell cycle, ↑ apoptosis, ↑ Intracellular adhesion, and ┬ cell survival and growth	Yu et al. (2010), Bovy et al. (2015), Jiang et al. (2016), Mutlu et al. (2016), Tao et al. (2016), Ke and Lou (2017), Zhou et al. (2017), Yuan et al. (2019), and Park et al. (2020)
miR-10b, miR-503, miR-122, miR-200, miR-105, and miR-21	Promotes distant metastasis	β-Catenin, Twist, HOXD10, ROCK, c-Jun, XIST, STAT3, NF-ĸB, PD-L1, PKM, GLUT1, Sec23a, YAP1, ZO-1, LZTFL1, and EMT	┬ Growth, ┬ Local immunity, ↑ EMT, motility, modulates cytoskeletal flexibility, and ↑ cell proliferation	Ma, 2010; Ma et al. (2010), Korpal et al. (2011), Liu et al. (2012), Yu et al. (2013), Zhou et al. (2014), Fong et al. (2015), Knirsh et al. (2016), Xing et al. (2018), and Wang et al. (2019)
miR-193a, miR-124-3p, miR-720, miR-31, miR-429, miR-124, and miR-1	Suppresses distant metastasis	Wnt-β-Catenin, ZEB1, CRKL, CrKL, MMP-9, PDC D6, E-cadherin, Fzd3, Rho A, ITGA5, IL-11, Frizzled 7, TNKS2, BCL2, EGFR, WTL, TWISR1, HER2, Vimentin, and N-Cadherin	┬ EMT, ┬ cell motility, ↑ apoptosis, and impair tumorigenesis	Barrett-Lee (2009), Lv et al. (2011), Li et al. (2013), Li et al. (2014), Liu et al. (2015), Ye et al. (2015), Xie et al. (2017), Cai et al. (2018), Zhang et al. (2018), Peng et al. (2020), and Zhang et al. (2020)
miR-22, miR-221/222, miR-143, miR-21, and miR-378e	Promotes stemness	TET, PTEN, Akt, NF-ĸB, COX-2, Sox2, Oct3/4, nanog, Zeb, and Snail	↑ Stemness biomarkers, ↑EMT, and induces clonal expansion	Song et al. (2013), Li et al. (2017a), and Donnarumma et al. (2017)
miR-34a and miR-140	Suppresses stemness	NOTCH1, Sox2, Sox9	┬ Stem cells, modulate stem cell renewal, and shrink stem cells	Park et al. (2014), Wolfson et al. (2014), Kim et al. (2016)
miR-155 and miR-132	Promotes angiogenesis	VHL/HIF, RAS, and VEGF	↓ Pro-angiogenetic substrates	Kong et al. (2014) and Kontomanolis et al. (2017)
miR-16, miR-503, and miR-100	Suppress angiogenesis	VEGF, FGF2, VEGFA, mtor, and HIF-1α	Modulate expression of pro-angiogenic molecules and ┬ angiogenesis	Lee et al. (2013), Zhou et al. (2013), and Pakravan et al. (2017)

↑- Increase/upregulation; ↓- Decrease/Downregulation; ┴- Inhibit/Prevent.