MDA-MB-231 breast tumor cells were cultured for 24 hours with titrating doses of DCA starting from 80 mM and diluted 2-fold to the lowest concentration of 2.5 mM (n ≥ 3). Supernatant lactate was measured as a ratio of the total cellular protein. Lactate production was measured under A) normoxia (O2 = 20%) and B) hypoxia (O2 = 1%). Asterisks (*) designate lactate production in DCA treated cells percentage that were significantly different from untreated control cells. Error bars are expressed as SEM.