Fig. 4

Validation of mRNA and protein expression levels of the three genes. The mRNA expression levels of GYPC (a), NME1 (b) and SLIT2 (c) in cigarette smoke-exposed cells. 2B, normal BEAS-2B cells serve as a control. S5 to S30, BEAS-2B cells exposed to cigarette smoke for different passages. d Heatmap of GYPC, NME1 and SLIT2 in BEAS-2B and four LUAD cell lines. Each column represents one cell line, and each row represents one gene; the gradual color ranged from blue to red represents the changing process from down-regulation to up-regulation. e Immunofluorescence staining of GYPC. f Immunofluorescence staining of NME1. g Immunofluorescence staining of SLIT2. h Western blotting results. S5 to S30, BEAS-2B cells exposed to cigarette smoke for different passages.*p < 0.05, versus normal BEAS-2B cells; **p < 0.01, versus normal BEAS-2B cells