Fig. 3.

Lorlatinib sensitizes melanoma to ferroptosis through SCD.

(A) The relative levels of GSH were assayed in A375 and SK-MEL-28 cells treated with DMSO, lorlatinib (5 μM), or IKE (2.5 μM) for 12 h. (B) Relative glutathione peroxidase activity were quantified in A375 and SK-MEL-28 cells with the indicated treatment for 6 h. Lorlatinib, 5 μM; RSL3, 2.5 μM. (C) Relative Fe²⁺ levels in A375 and SK-MEL-28 cells following treatment with DMSO or lorlatinib (5 μM) for 12 h. (D) CoQ10 levels at different time point in A375 cells after treatment with 5 μM lorlatinib, or in A375 cells treated with different concentrations of lorlatinib for 12 h. (E) Western blotting analysis of proteins at different time point in A375 cells after treatment with lorlatinib (5 μM), or proteins in A375 cells treated with different concentrations of lorlatinib for 12 h. (F) Fold change of lipid species in A375 cells treated with 5 μM lorlatinib for 12 h in negative and positive ionization modes. (G) SCD protein levels were quantified by western blotting in control (sgCtrl) and SCD deficient (sgSCD) cells. (H-I) Dose response of RSL3-induced death of sgCtrl and sgSCD cells in the presence of DMSO or lorlatinib (5 μM) for 6 h. (J) SCD protein levels were quantified by western blotting in cells with control (vector) or SCD overexpression (SCD ov). (K) Viability of the indicated cells with control or SCD overexpression after treatment with RSL3 (2.5 μM), lorlatinib (2.5 μM), or RSL3 + lorlatinib. P values were determined using one-way ANOVA analysis in A, B, D. Two-tailed unpaired Student's t-test was performed in C. Two-way ANOVA analysis was performed in K. **, P < 0.01; ***, P < 0.001; ns, no significance.