Fig. 5: FSP1 aids cellular transformation and promotes tumor onset in vivo.
From: Elevated FSP1 protects KRAS-mutated cells from ferroptosis during tumor initiation
a NIH-3T3 KRASG12V cells were treated either with DMSO, iFSP1 [10 µM, 20 µM], Fer-1 [5 µM] or both and subjected to soft agar assays for 18 days. Colony images were quantified using ImageJ. b The human NSCLC cell line A549 was treated as indicated and subjected to growth in soft agar for 30 days. Image analysis was done as in (a). c Indicated cells were grown in Matrigel for spheroid formation under the indicated treatment for 14 days. Images were quantified using the BZ-H4M/Measurement Application Software (Keyence). d A549 cells were subjected to spheroid assay growth for 9 days and treated either with DMSO, iFSP1 [10 µM], Fer-1 [2,5 µM] or both. Images were quantified using the BZ-H4M/Measurement Application Software (Keyence). c 8-weeks old male nude mice were injected with 5 × 105 cells of the indicated cell lines (G12D e.V. (empty Vector) n = 11; G12D shFSP1 n = 12; WT e.V. n = 24 + Vehicle; WT e.V. + Liproxstatin-1 n = 10; WT FSP1 n = 24 + Vehicle; WT FSP1 + Liproxstatin-1 n = 10) into both flanks. Mice were injected 5× per week either with vehicle (PBS with 1% DMSO) or Liproxstatin-1 (10 mg/kg). Time until palpable tumors (min. 2 × 2 mm) were detected is depicted (tumor onset). Representative ex vivo tumors were analyzed for FSP1 expression. f Pancreatic organoids were treated with DMSO, RSL3 [100 nM] or iFSP1 [10 µM] alone or in combination with Ferrostatin-1 (Fer-1) [5 µM] for 48 h. Images were quantified using the BZ-H4M/Measurement Application Software (Keyence). Data are means ± SEM of at least three independent experiments in each individual cell line or representative images were applicable. Two-way ANOVA (a, b, c, d), log-rank test (e), two-tailed t-test (f), ****p < 0.0001, ***p < 0.001, **p < 0.01, *p < 0.05.
