To determine the impact of Smad4-depleted H1299 cells on the dynamic changes in lamellipodia and filopodia, stable knockdown of Smad4 by a specific shRNA (shSmad4) in the human lung cancer cell line H1299 (H1299-shSmad4, Supplementary Fig. 2c), which has an activated RAS and p53 LOF mutations, stimulated by serum were evaluated by cell spreading and morphological changes (Supplementary Fig. 2d). Here, TP53 is linked to lung cancer.