It was found that novel SM epoxides induced the death of tumor cells at low micromolar concentrations (IC50(24h) = 0.7–4.1 μM) via the induction of mitochondrial-mediated apoptosis, reinforced intracellular accumulation of doxorubicin in B16 melanoma cells, probably by direct interaction with key drug efflux pumps (P-glycoprotein, MRP1, MXR1), and the suppressed pro-metastatic phenotype of B16 cells, effectively inhibiting their metastasis in a murine model. The gene discussed is ABCG2; the disease is melanoma.