SLC1A1 and central nervous system cancer: The N-(2-(18F)fluoropropionyl)-L-glutamate ((18F)FPGLU) is a promising amino acid tracer for PET imaging of tumors with a high expression of extracellular Glu transporter excitatory amino acid carrier 1 (EAAC1) such as glioma and lung adenocarcinoma [213].