The amide derivative 1 had the greatest affinity for LAT1, and its IC50 value was lower (2.2 μM) in astrocytes as compared to previously determined values in human breast adenocarcinoma cells (MCF-7; 14.2 μM), while the opposite was observed for derivative 2 (8.9 μM vs. 1.1 μM in MCF-7). This evidence concerns the gene SLC7A5 and breast adenocarcinoma.