While these newly discovered substrate binding site inhibitors show improved potencies and selectivities (Garibsingh et al., 2021), because of their high similarity to amino acid substrates they (i) likely have poor bioavailability and (ii) need to compete with the amino acid-rich media; thus, they are unlikely to be useful as future anti-cancer drugs via inhibition of ASCT2-mediated transport. The gene discussed is SLC1A5; the disease is cancer.