Figure 3.

 Effects of l‐type amino acid transporter 1 (LAT1) inhibitors on HT‐29 cells. (a) Effects on ¹⁴C‐leucine uptake. HT‐29 cells, S2‐LAT1 cells, and S2‐LAT2 cells were seeded to a 24‐well microtiter plate and incubated in the presence of 5% CO₂ at 37°C or 33°C for 2 days. Then, the incubation medium was replaced with a Hanks’ solution (37°C) containing ¹⁴C‐leucine and a test compound, and the mixture was incubated for 1.0 min to allow radioactivity uptake. The cells were solubilized and the cell lysate counted for radioactivity with a scintillation counter. The figure shows the effects of KYT‐0353 (left) and KYT‐0284 (right) on the cellular ¹⁴C‐leucine uptake by various cells with uptake rates (%) on the ordinate and test compound concentrations (μm) on the abscissa. The symbols , •, and , show HT‐29, S2‐hLAT1, and S2‐hLAT2, respectively, with perpendicular bars of SD. (b) Growth inhibitory effects. HT‐29 cells, S2‐hLAT1 cells, and S2‐hLAT2 cells were seeded to a 24‐well microtiter plate and incubated in the presence of 5% CO₂ at 37°C or 33°C for 24 h. Then, test compounds at various concentrations were added and further incubated for 96 h. After incubation, the cells were counted with a Coulter cell counter. The symbols , •, and show HT‐29, S2‐hLAT1, and S2‐hLAT2, respectively, with perpendicular bars of SD.