SLC16A1 and cancer: Catabolite transporters allow for export from CAFs (monocarboxylate transporter 4 (MCT-4)) and uptake (monocarboxylate transporter 1 (MCT-1), glutamine transporter) into adjacent cancer cells, where they are used to generate energy via OXPHOS or for anabolic processes to support cell division and tumor mass [33,39].