Table 2. Expression of miRNAs associated with breast cancer development.

Expression	MicroRNAs	Characteristics	References
Downregulated	MiR-200c	Invasion and metastasis	(34)
	MiR-205	Drug resistance	(35)
	MiR-141	Cellular proliferation, invasion and metastasis	(36)
	MiR-1	Cellular proliferation, invasion, metastasis and drug resistance	(37)
	MiR-34a	Cellular proliferation, invasion, metastasis and drug resistance	(34)
Upregulated	Let-7	Cellular proliferation	(31)
	MiR-221	Cellular proliferation and drug resistance	(38)
	MiR-21	Cellular proliferation, invasion, metastasis and drug resistance	(39,40)