Table 1.

Studies assessing miRNAs expression in plasma among colorectal tumor patients and healthy controls

Ref.	Author(s), year	Study population				Methods	Normalization controls	miR
		Country	Cases (stage I/II/III/IV)	Control	Age mean (range)			Tested miRs (No.)	Significant miRs (No.)	Difference between cases and controls (P)
15	Pu et al., 2010	China	103 (7/38/40/18) CRC	32 healthy	CRC 58 (median; 39–84) Control 32 (median; 17–77)	SYBR green qRT-PCR	–	3	1	miR-221↑	P = 0.0021
16	Huang et al., 2010	China	100 (27/25/38/10) CRC^a	59 healthy^a	CRC 61 (26–84)	SYBR green qRT-PCR	miR-16	12	2	miR-29a↑	P < 0.0001
			37 advanced adenomas^a		Adenoma 55 (34–75)					miR-92a↑	P < 0.0001
					Control 58 (27–81)					miR-29a↑	P < 0.0001
										miR-92a↑	P < 0.0001
17	Ng et al., 2009	China	130 (6/35/39/50) CRC^b	75 healthy^b	CRC 71 (42–91)	Cancer microRNA array and SYBR green qRT-PCR	RNU6B	95	2	miR-17–3p↑	P < 0.0001
					Control 69 (45–85)					miR-92↑	P < 0.0001

↵^a3 miRs were selected from 12 miRs on a set of plasma samples (20 cases vs. 20 controls), then validated in 80 CRC, 37 advanced adenomas, and 39 healthy controls.
↵^b5 miRs were selected from 95 miRs by comparing miRNA profiles from plasma of 5 CRC patients versus 5 age-matched healthy controls and tissues of 5 CRC patients versus 5 adjacent normal tissues with miRNA Array, then 2 miRs were seclected from the validation on a small set of plasma samples (35 cases vs. 20 controls) by qRT-PCR, then a large-scale validation on plasma samples (90 cases vs. 50 controls).