Multi-layered cellulose nanocrystal system for CD44 receptor-positive tumor-targeted anticancer drug delivery

Layer-by-layer approach based on the electrostatic interactions has been introduced to make multi-layered targeting ligand-chemotherapeutics-cellulose nanocrystal (CNC) structure for tumor-targeted drug delivery. Negatively charged CNC was covered with cationic doxorubicin (DOX) molecule (as a chemotherapeutic agent) to fabricate DOX@CNC and sequentially wrapped with anionic hyaluronic acid (HA) polymer (as a CD44 receptor targeting ligand). Rod-shaped HA-coated DOX@CNC (HA@DOX@CNC) has been successfully fabricated and it exhibited 327 nm length, 12 nm width, -38 mV zeta potential, and 3% DOX content. HA@DOX@CNC displayed higher cellular accumulation efficiency and antiproliferation potentials in CD44 receptor-positive lung adenocarcinoma (A549) cells compared to DOX and DOX-wrapped CNC (DOX@CNC). In A549 spheroid model, HA@DOX@CNC group exhibited superior tumor penetration capability, reactive oxygen species (ROS) production level, and cancer cell killing capacity rather than DOX and DOX@CNC group. In A549 tumor implanted mouse model, Cy5.5-labeled HA@DOX@CNC group exhibited higher tumor accumulation efficiency rather than free Cy5.5 after intravenous injection. All these findings suggest that designed HA@DOX@CNC can be one of promising biocompatible tumor-targeted nano-size drug delivery systems.