Differentially expressed microRNAs | Groups compared | |||||||
0 and 1 | 0 and 2 | 0 and 3 | 1 and 2 | 2 and 3 | 2 and 3A | 3A and 3B | CIS and 3B | |
Total number | 6 | 19 | 19 | 16 | 30 | 15 | 20 | 10 |
Downregulated | 5 (83) | 16 (84) | 14 (74) | 14 (87.5) | 17 (57) | 3 (20) | 8 (40) | 5 (50) |
Upregulated | 1 (17) | 3 (16) | 5 (26) | 4 (12.5) | 13 (43) | 12 (80) | 12 (60) | 5 (50) |
Data are presented as n or n (%). CIS: carcinoma in situ. Two successive waves were observed in microRNA expression profiles during lung squamous carcinogenesis: first, a downregulation and, secondly, an upregulation of microRNAs. In the first four comparisons of microRNA profiles, between groups 0 and 1, 0 and 2, 0 and 3, and 1 and 2, the large majority of microRNAs were downregulated. In the later four comparisons, the proportion of downregulated microRNAs decreased and that of upregulated microRNAs increased, with ≥50% being upregulated for comparisons between groups 2 and 3A, 3A and 3B, and CIS and 3B.