ECH1 and glioblastoma: However, upon the addition of etomoxir (ETO), a CPT1 inhibitor that blocks the transport of long-chain FAs into mitochondria for FAO (34), ECH1 depletion did not further decrease the basal and maximal respiration capacity or ATP production in GBM cells (Figure 5, B–D, and Supplemental Figure 5, C–E).