Efficient tumor targeting of hydroxycamptothecin loaded PEGylated niosomes modified with transferrin.

The aim of the present report was to exploit the possibility of combination of the stealth action by polyethylene glycol cyanoacrylate-co-hexadecyl cyanoacrylate (PEG-PHDCA) modified niosomes and active targeting function of transferrin (Tf) by transferrin receptor-mediated endocytosis to promote drug delivery to solid tumor following intravenous administration with hydroxycamptothecin (HCPT) as model drug. HCPT-loaded PEG-niosomes (PEG-NS) were prepared by thin-film hydration and ultrasound method; the periodate-oxidated Tf was coupled to terminal amino group of PEG to produce the active targeting vesicles with average diameters of 116 nm. The uptake of Tf-PEG-NS into KB cells was concentration and time dependent, which could be inhibited by low temperature and free Tf, indicating that the endocytosis process was energy-driven and receptor specific. Compared with HCPT injection, non-stealth niosomes and PEG-NS, Tf-PEG-NS demonstrated the strongest cytotoxicity to three carcinomatous cell lines (KB, K562 and S180 cells), the greatest intracellular uptake especially in nuclei, the highest tumor concentration and largest area under the intratumoral hydroxycamptothecin concentration curve, as well as the most powerful anti-tumor activity with the inhibition rate of 71% against S180 tumor in mice. The results showed that the transferrin modified PEGylated niosomes could be one of the promising solutions to the delivery of anti-tumor drugs to tumor.