SLC1A5 and cancer: One of the anti‐cancer mechanisms mediated by mAb is internalization; that is, cell surface targets are transferred into the intracellular part after the binding of antibodies.38, 39, 40 Membrane localization of green fluorescence was observed in untreated HEK293 (Figure 2A, left) and RH7777 (data not shown) cells expressing ASCT2‐GFP, whereas intracellular localization of green fluorescence was observed in cells treated with Ab3‐8 (Figure 2A, middle and right).