Table 2. Some studies on circulating miRNAs for diagnosis of lung cancer.

miRNA	TNM stage	Source	Detection method	Performance	Details
miR-429,miR-205, miR-200b,miR-203,miR-125b,miR-34b	I-IV	serum	qRT-PCR	Sen=88% Spe=71% AUC=0.88 (I/II) AUC=0.89 (I/V) Threshold value=0.37	NSCLC (n=100) [64] non-cancer (n=58)
miR-146a,miR-222,miR-223	I-III	serum	qRT-PCR	AC vs HD: Total AUC=0.951 Sen=84.35% Spe=90.83% Acu=87.27% Cutoff value = 0.5015	Training set [65] AC (n=40) HD (n=40)
				In AC AUC=0.942 (I) AUC=0.968 (II) AUC=0.954(III)	Validation set AC (n=120) HD (n=120)
miR-21,miR-145, miR-155	I-III	plasma	qRT-PCR	Training set LC vs HS Total AUC=0.847 Sen=69.4% Spe=78.3% Cutoff value: 1.310, 0.4950,0.01535	Training set [66] LC (n=62) HS(n=60)
				Validation set LC vs HS Total AUC=0.841 Sen=76.5% Spe=80.0%	Validation set LC (n=34) BPN (n=30) HS (n=32)
miR-146b,miR-205,miR-29c, miR-30b	I-III	serum	qRT-PCR	Training set AUC=0.99 Sen=93.65% Spe=93.33% Acu=95.00% Cutoff value = 0.5606	Training set [67] NSCLS (n=63) HS (n=15)
				Validation set AUC=0.93 Sen=78.13% Spe=95.38% Acu=89.69%	Validation set NSCLS (n=65) Cancer-free (n=32)
				In NSCLC AUC=0.96(I) AUC=0.95(II-III)
miR-1254 MALAT1 miR-485-5p miR-574-5p	I-IV	serum	qRT-PCR	AUC=0.864/0.848/ 0.878/0.732(I/II/III /IV) Sen=94.6%/89.7%/ 94.9%/66.7%(I/II/III /IV) Spe=75.7%(I/II/III/ IV)	Training set [68] NSCLS (n=36) HS (n=36)
					Validation set NSCLS (n=120) HS (n=71)

Abbreviation: Sen: sensitivity; Spe: specificity; Acu: accuracy; AC: lung adenocarcinoma; HD: healthy donor; HS: healthy smoker; LC: lung cancer; BPNs: benign pulmonary nodules; SCC: squamous cell carcinoma.