Fig. 3

NHE1, NBCn1, MCT1 and MCT4 expression in MCF-7 and MDA-MB-231 spheroids relative to 2D culture. MCF-7 and MDA-MB-231 spheroids (3D) and 2D cultures were grown 4 days in parallel, followed by lysis and Western blotting with antibodies directed against the specific transporters. Top panels in a, b, c and d show representative Western blots, while lower panels show quantifications of band intensities normalized to that of corresponding 2D culture. a: NHE1 (MCF-7: 5n, MDA-MB-231: 3n). b: NBCn1 (MCF-7 and MDA-MB-231: 3n). c: MCT4 (MCF-7 and MDA-MB-231: 3n). d: MCT1 (3n). Error bars denote SEM. A two-tailed, paired Student’s t-test was used to test for statistically significant difference in means between the two groups. * and *** indicate p < 0.05 and p < 0.001, respectively