Cell-Penetrable Lysine Dendrimers for Anti-Cancer Drug Delivery: Synthesis and Preliminary Biological Evaluation

Improving the cell penetration and enhancing the cell selectivity of drugs have been approved for overcoming the major drawbacks of chemotherapeutic agents: the toxicity to normal cells and the drug resistance in tumors. In this paper, lysine dendrimers (G1-G3) were chosen as novel cell-penetrating carriers for anti-cancer drugs based on the internalization mechanism of cell-penetrating peptides and the characteristics of dendritic peptides. After labeling with fluorescein isothiocyanate (FITC), the cell-penetrable capacity of lysine dendrimers was certified by flow cytometric analysis. In a preliminary biological evaluation, the conjugates of lysine dendrimers and 5-fluorouracil showed the expected advantages: stable drug release, low toxicity to normal cells, and moderate inhibition of tumor cells. These results imply that cell-penetrable lysine dendrimers could be potential carriers in drug delivery of anti-cancer medicine.