To investigate whether the TTF-1 promoter might be an ideal candidate for operating miR-7 expression in lung cancer, as shown in Figure 1A, we first amplified and inserted the sequence of both TTF-1 promoter and miR-7 into pGL3.0 basic vector and successfully constructed an eukaryotic expression vector, which could express miR-7 operated by TTF-1 promoter (termed as p-T-miR-7) (Figure S1). This evidence concerns the gene TTF1 and lung cancer.