Thus, ASCT2 is a potential cancer drug target, where a compound interacting with ASCT2 can be an inhibitor that deprives the cancer cells of nutrients, a cytotoxic ASCT2 substrate with an intracellular target (e.g., a metabolic enzyme), or a low affinity ligand (a substrate or inhibitor) that acts as inhibitor or substrate on multiple targets, including ASCT2 [9]. The gene discussed is SLC1A5; the disease is cancer.