Fig. 1: Mutation at Arg¹⁵⁸ is a GOF p53 isoform.

a–d Cell invasion assays were performed on isogenic Calu-1 cells (p53^−/−, p53^wt and mutp53^R158G) and H2170 cells. Cells seeded in Matrigel invasion chambers were fixed and stained at the indicated time point. Representative images were shown for Calu-1 clones (n = 3 independent experiments) (a) and H2170 cells with Scr of TP53 siRNA knockdown (n = 2 independent experiments) (c). Immunoblots verifying p53 knockdown are shown on the right. The number of cells in four random microscopic fields ×4 were quantified for Calu-1 (b) and H2170 (d) cells. Data are expressed as mean ± SD. 50 nM of siRNA used per transfection. Two tailed Student’s t-test; *P < 0.05. Scale bar, 200 µm. e, f Anchorage-independent colony forming assays were performed on isogenic Calu-1 cells (p53^−/− and five independent mutp53^R158G clones). Representative images of colony formation for each cell type, stained with MTT at assay endpoint (e). The number of colonies were quantified (f) and expressed as mean of triplicates ± SD (n = 3 independent experiments). Two tailed Student’s t-test; *P < 0.05. g, h In vivo growth rates of p53^−/−, p53^wt, p53^R158G cells were measured upon day of implantation and monitored over time (g). Images shown are representative tumor sizes at assay endpoint (h). Tumor sizes are presented as mean ± SEM (n = 5 animals). Two-way ANOVA with Bonferroni correction; *P < 0.05; **P < 0.01; ***P < 0.001.