Fig. 8. Combinatorial targeting of MTHFD2 and PAICS induces cell apoptosis, and a low-low expression of MTHFD2 and PAICS suppresses patient survival in neuroblastoma.

a–d Apoptotic cell death was measured by flow cytometry for drug combination assay. a, c Representative flow cytometry profiles using Annexin V-FITC/PI staining for apoptosis in SK-N-DZ (a) and SK-N-BE(2)-C (c) cells. b, d Quantification of apoptotic cells between anisomycin, apicidin, and the combined treatment in SK-N-DZ (b) and SK-N-BE(2)-C (d) cells. Experiments are performed in triplicate and data are expressed as the mean ± SEM. *P < 0.05; **P < 0.01; ***P < 0.001. e, f Kaplan-Meier survival curves of overall and event-free survival of patients with neuroblastoma. Neuroblastoma patients with high-high expression of MTHDF2 and PAICS (H_MTHFD2H_PAICS); low-low expression of MTHDF2 and PAICS (L_MTHFD2L_PAICS), and high-low or low-high expression of MTHFD2 and PAICS (H_MTHFD2L_PAICS or L_MTHFD2H_PAICS) from SEQC (e) and TARGET (f) neuroblastoma cohorts. The median of the gene expression was used as the cutoff to straitify patients into high and low groups. The differences in survival time between groups were assessed by the log-rank test