Figure 1.

Schematic representation of the established PK/PD model of DEX in nude mice. X_a, X_c and X_p represent the level of DEX in the absorption, central and peripheral compartments of the PK model, respectively; X represents the tumor size with proliferating tumor cells in the tumor compartment; K_a represents the first order absorption rate; CL represents the systemic clearance, which was time-dependent; Q represents the clearance between compartments; V_c and V_p are the apparent volumes of distribution in the central and peripheral compartments, respectively; and F is the bioavailability.