Extended Data Fig. 10: PSAT1 pS337 blockade improves ICB therapeutic efficacy.

a–c, Immunoprecipitation and immunoblotting analyses were performed with the indicated antibodies. Representative results from at least three independent experiments were shown. a,b, The indicated MDA-MB-231 were treated with the indicated peptides with or without IFNγ (25 ng ml⁻¹) for 2 h. d, MDA-MB-231 cells were treated with CHX for the indicated time together with IFNγ (25 ng ml⁻¹) and the indicated peptides for 9 h. Relative intensity of GPX4 to β-tubulin was analyzed. Data are the mean ± s.d., n = 6 independent experiments, two-tailed Student’s t test. d,e, MDA-MB-231 and BT549 cells were treated with IFNγ (100 ng ml⁻¹) and the indicated peptides in the absence or presence of Fer1 (10 μM) for 24 h. Lipid ROS-positive cells (d) and cell death (e) were measured. Data are the mean ± s.d., two-tailed Student’s t test. All experiments were repeated three times independently with consistent results. f–i, 4T-1 cells were mammary pad-orthotopically injected into BALB/c female mice (n = 6 per group). These mice were given anti-mPD-1 antibody (100 μg/100 µl) or control hamster IgG (100 μg/100 µl) by i.p. injection starting on the seventh day after tumor inoculation and treated every 3 days a time for a total of five treatments. The resulting tumors were resected 28 days after injection (f), and tumor weight (g) was calculated. Data are presented as the mean ± s.d., two-tailed Student’s t test. IHC analyses of the indicated mammary pad-orthotopic tumors from BALB/c mice were performed with the indicated antibodies. Representative staining images are shown (h). The indicated staining scores for the indicated tumor samples were compared using two-tailed Mann–Whitney U test (i). Data are the mean ± s.d.

Source data