LAT1 catalyzes the transport of the thyroid hormones triiodothyronine (T3) and thyroxine (T4), but also amino-acid-mimicking drugs, such as the antiparkinsonian drug L-dopa, anti-cancer agent melphalan, muscle relaxer baclofen, and anticonvulsants gabapentin and pregabalin (Table 3). Here, SLC7A5 is linked to cancer.