Fig. 6

PEPCKi blocks lactate utilization. Relative abundance of m + 3 a pyruvate, b PEP, and c 3PG, and m + 2 d citrate, e fumarate, and f succinate were determined from Colo205 cells following incubation with ¹³C₃ lactate and treated with PEPCKi. Relative abundance of g m + 16 palmitate and h m + 14 myristate were determined from Colo205 cells incubated with ¹³C₃ lactate and treated with PEPCKi. Cells were incubated in reduced nutrient media with and without 10 μM PEPCKi overnight, incubated with 10 mM ¹³C lactate for 6 h (polar) or 16 h (non-polar), and metabolites harvested and analyzed using GC/MS. N ≥ 3 ± SD. i Colo205 and j Moser cells were treated with PEPCKi with and without lactate and cell number determined after 5 days. k Ls174T were grown as spheroids and treated with PEPCKi in the presence or absence of lactate. Images taken after 48 h. Spheroid size was measured using ImageJ. Scale bar = 50 μm. N = 3 ± SD. NS, not significant. *p < 0.05, **p < 0.01, ***p < 0.001