A targeted nanocarrier based on polyspermine for the effective delivery of methotrexate in nasopharyngeal carcinoma

Antitumor efficacy of methotrexate (MTX) is seriously limited due to its poor water solubility, nonspecific tumor distribution and low bioavailability. To overcome these obstacles, polyspermine (PSP) conjugated with MTX and folic acid (FA) as a novel targeted prodrug was designed and has been successfully synthesized using the amidation reaction. The strong hydrophilic properties of PSP made MTX well dispersed in water and the cellular uptake study indicated that the presence of FA enhanced uptake of the FA-PSP-MTX in folate receptor (FR) over-expressing human nasopharyngeal carcinoma HNE-1 cells. ¹H NMR spectra and UV-Vis spectral analysis were carried out to confirm the MTX and FA content in FA-PSP-MTX, respectively. In CCK-8 assay and apoptosis analysis, the prodrug showed significantly enhanced anticancer efficacy than free MTX in HNE-1 cells. These results suggested that the prodrug has the potential for targeted delivery of MTX into cancer cells to improve its anti-tumor efficacy.