Nanoparticles for tumor-specific intracellular drug delivery

Near-infrared fluorescent imaging of metastatic ovarian cancer using folate receptor-targeted high-density lipoprotein nanocarriers

AIM

The targeting efficiency of folate receptor-α (FR-α)-targeted high-density lipoprotein nanoparticles (HDL NPs) was evaluated in a syngeneic mouse model of ovarian cancer.

MATERIALS & METHODS

Folic acid was conjugated to the surface of fluorescent-labeled HDL NPs. In vivo tumor targeting of folic acid-HDL NPs and HDL NPs were evaluated in mice with metastatic ovarian cancer following intravenous or intraperitoneal (ip.) administration.

RESULTS & DISCUSSION

Intravenous FR-α-targeted HDL resulted in high uptake of the fluorescent nanoparticle in host liver and spleen. The ip. injection of fluorescent HDL produced moderate fluorescence throughout the abdomen. Conversely, animals receiving the ip. FR-α-targeted HDL showed a high fluorescence signal in ovarian tumors, surpassing that seen in all of the host tissues.

CONCLUSION

The authors' findings demonstrate that the combination of local-regional ip. administration and FR-α-directed nanoparticles provides an enhanced approach to selectively targeting ovarian cancer cells for drug treatment.

Smart multifunctional nanostructure for targeted cancer chemotherapy and magnetic resonance imaging

Targeted chemotherapy and magnetic resonance imaging of cancer cells in vitro has been achieved using a smart multifunctional nanostructure (SMN) constructed from a porous hollow magnetite nanoparticle (PHMNP), a heterobifunctional PEG ligand, and an aptamer. The PHMNPs were prepared through a three-step reaction and loaded with the anticancer drug doxorubicin while being functionalized with PEG ligands. Targeting aptamers were then introduced by reaction with the PEG ligands. The pores of the PHMNPs are stable at physiological pH, but they are subject to acid etching. Specific binding and uptake of the SMN to the target cancer cells induced by aptamers was observed. In addition, multiple aptamers on the surface of one single SMN led to enhanced binding and uptake to target cancer cells due to the multivalent effect. Upon reaching the lysosomes of target cancer cells through receptor-mediated endocytosis, the relatively low lysosomal pH level resulted in corrosion of the PHMNP pores, facilitating the release of doxorubicin to kill the target cancer cells. In addition, the potential of using SMN for magnetic resonance imaging was also investigated.