In this study, we investigated the effect of combining mitotane with FTY720 in ACC cells, and the results showed that the combination only resulted in a greater anti-proliferative effect over single agent treatment in SW13 cells, indicating that the combined therapy of SphK1 inhibition and mitotane may not be always favorable for ACC patients. The gene discussed is SPHK1; the disease is adrenal cortex carcinoma.