Fig. 3. FASNi inhibits fatty acid synthesis and ß-oxidation in both KM and KRAS-WT cells.
a GC/MS quantification of newly synthesized FA in H460 and H522 cells after overnight ethyl acetate-2-13C labeling, treated as indicated. Either M + 2/M + 0 or M + 4/M + 0 ratio is reported. Palmitate, FA 16:0; palmitoleate, FA 16:1n7; vaccenate, FA 18:1n7; oleate, FA 18:1n9 (n = 3 independent experiments). b, c Relative quantification of malonyl-CoA and NAPH of vehicle- and FASNi-treated LC cells (n = 3 independent experiments). d Oil red O staining for lipid droplets in H460 and H522 cells. e, f Relative quantification of FA ß-oxidation (FAO) and AMP in the indicated cells treated with vehicle or FASNi (n = 3 and n = 4 biologically independent samples). g Immunoblot of phospho-Ser79-ACC1 (pACC1S79), ACC1, FASN, phosphor-Thr172-AMPK (pAMPKT172) and AMPK. h Schematic of the AMPK/ACC1/FASN axis. FASNi inhibits the synthesis of palmitate (FA 16:0) thereby blocking the synthesis of complex lipids and ß-oxidation (FAO). These events trigger the activation of AMPK, which in turn phosphorylates and deactivates ACC1. ACC1 phosphorylation blocks the synthesis of malonyl-CoA (the substrate for FA 16:0 synthesis) potentiating the inhibitory effects of FASNi. Bars express mean ± SD. Statistical analyses were done using two-tailed unpaired Student’s t-test.