Fig. 4

Phosphorylation of FoxM1 at Ser25 facilitates metastasis of NSCLC in a tail-vein injection model. A549 cells expressing RFP-tagged WT, S25A, and S25E of FoxM1 were injected intravenously into the tail-veins of four-week-old BALB/c nude mice, and the tumorigenic and metastatic properties were evaluated after 15 weeks. a Representative lung tumor from the mouse model (left panel). The number of metastatic lung tumors was counted and plotted. (n = 4 or 5) (right panel). Data are presented as mean ± SD. b, c Representative H&E staining (b, left panel) and Ki-67 staining (c, left panel) were performed using lung tissue from the mice.The relative density of H&E staining (b, right panel) and Ki-67-positive cells (c, right panel) was analyzed and plotted. *p < 0.05; **p < 0.01; ***p < 0.001. Data are presented as mean ± SD. d Immunoblotting was performed using lung tissue lysates from each mouse model. FoxM1, RFP, E-cadherin, N-cadherin, vimentin, SNAI1, PD-L1, and β-actin were detected using specific antibodies (left panel). The band intensity values were quantified using LI-COR Odyssey software, normalized, and plotted (right panel). e qRT-PCR was performed for CDH1, CDH2, SNAI1, VIM, and CD274 using lung tissue lysates from each mouse model. The relative mRNA expression was plotted. *p < 0.05; **p < 0.01; ***p < 0.001 compared with experimental control. ^#p < 0.05; ^###p < 0.001 compared with S25A FoxM1