SLC38A7 and neoplasm: An unequivocal link between one PC and one biologically relevant micro-parameter is not guaranteed either—nor is it the case for the kinetic parameters—which both capture complex amino acid transport processes dependent, among others, on the number of amino acid transporters along the endothelial and tumor cell membrane, the concentrations of all endogenous transporter shared substrates in every model compartment, and the relative sizes of the compartments and thus (over-) cellularity [38].