Fig. 2: 3D-spheroids oxidize glucose via the TCA cycle for elevated ATP production.

A Comparison of ATP levels normalized to protein concentration in cells cultured in 2D- and 3D-cultured cells using A2780, IGROV1, OVCAR3, OVCAR8, ES2, and SKOV3 cells (n = 3 independent experiments). B Left: Comparison of MitoTracker Orange CMTMRos and MitoTracker Green FM normalized to cell counts in 2D- and 3D-cultured A2780 cells (n = 6 independent experiments). Right: Comparison of MitoTracker Orange CMTMRos and MitoTracker Green FM normalized to cell count in cells cultured in 2D- and 3D-cultured IGROV1 cells (n = 6 independent experiments). C Comparison of key metabolite levels in glycolysis and TCA cycle in both 2D- and 3D-cultured cells after 24 h of incubation. The carbon distribution of the metabolites was also illustrated. Additionally, lactate secretion into the medium after 24 h of incubation is presented (n = 3 independent replicates). The red circles indicate carbon. “m + 0” represents the carbon contribution from sources other than ¹³C₆-glucose, and “m + 1,” “m + 2,” etc. represent the carbon contribution from ¹³C₆-glucose (¹³C isotopologues). G6P: glucose-6-phosphate, F6P: fructose-6-phosphate, 3PG_2PG: 3-phosphoglycerate or 2-phosphoglycerate, PEP: phosphoenolpyruvate, α-KG: alpha-ketoglutarate, PC: pyruvate carboxylase, PDH: pyruvate dehydrogenase. Graph data were presented as mean ± SD of multiple experiments.