While there is currently no clinical compound that selectively targets COX4I1, we noted that chlorpromazine (CPZ; Figure7A), an FDA‐approved antipsychotic medication, was reported to suppress chemoresistant COX4I1‐expressing glioma cells by inhibiting mitochondrial Complex IV activity.[24] Treatment of chlorpromazine resulted in disorganized mitochondrial cristae ultrastructure (Figure 7B), widened cristae lumen (Figure 7C), facilitated cytochrome c release from mitochondria to the cytosol (Figure 7D), and reduced mitochondrial respiration (Figure 7E) in Molm13 cells. Here, CYCS is linked to central nervous system cancer.