SLC6A14 and colonic neoplasm: Published reports have demonstrated the therapeutic utility of α-methyl-l-tryptophan as a fairly selective inhibitor of SLC6A14 in the treatment of breast cancer (Karunakaran et al., 2011), pancreatic cancer (Coothankandaswamy et al., 2016), and colon cancer (Sikder et al., 2020).