Fig. 6

Metabolic shift by MBX-2982 and inhibition of gefitinib-induced autophagy by lactate. a AMPK activity was determined by immunoblottings for phosphorylated AMPK and phosphorylated ACC proteins in MCF-7 cells treated with 10 μM MBX-2982. b ATP content was determined by ATP assay kit in MCF-7 cells. Cells were treated with MBX-2982 (1-10 μM). c Effects of GPR119 agonists on mitochondrial OXPHOS and glycolysis in MCF-7 cells. d MCF-7 cells were pretreated with or without 2-deoxyglucose (2-DG, 50 mM) for 30 min and incubated with 10 μM MBX. e MCF-7 cells were pretreated with or without GSK2837808 (LDH inhibitor, 10 μM) for 30 min and incubated with 10 μM MBX. f MBX-induced lactate production in MCF-7 (left) and shGPR119-MCF-7 cells (right). Lactate concentration was assessed by 1H-NMR or lactate assay kit in total cell lysates and culture media. g MCF-7 cells were incubated with 10 μM gefitinib in the presence or absence of MBX for 24 h and concentrations of glucose and lactate were determined by 1H-NMR in total cell lysates (left) and culture media (right). h and i MCF-7 cells were treated with MBX for 24 h and protein expression of lactate transporters and lactate converting enzymes were measured by western blottings. j MCF-7 cells were treated with MBX-2982 for 24 h and LDHA activity was determined by LDH assay kit. k MCF-7 cells were incubated with 10 μM gefitinib in the presence or absence of lactate (2.5-20 mM) for 24 h, and LC3B I/II were measured by immunoblottings. l Caspase3/7 activation by gefitinib with lactate. MCF-7 cells were treated gefitinib (10 μM) with or without lactate (5-20 mM) for 72 h. Data represent the mean ± S.D. (n=3). * p < 0.05, ** p < 0.01,*** p < 0.005 significanct difference between the two indicated groups