Prolonged blood circulation outperforms active targeting for nanocarriers-mediated enhanced hepatocellular carcinoma therapy in vivo.

Successful hepatocellular carcinoma (HCC) therapy in vivo remains a significant challenge due to the down-regulated expression of the receptors on the surface of tumor cells for compromised active targeting efficiency and cellular uptake of nanoparticles (NPs)-based drug delivery systems (DDSs) and "accelerated blood clearance" and premature unpackaging of NPs in vivo induced by the poly(ethylene glycol)ylation (PEGylation). Inspired by the repeatedly highlighted prolonged blood circulation property of RBCm-camouflaged NPs, we hypothesis that the prolonged blood circulation property resulting from RBCm coating outperforms the active targeting mechanisms of various targeting ligands for enhanced HCC therapy in vivo. Clarification of this hypothesis is therefore of great significance and urgency to break the afore mentioned bottlenecks that hamper the efficient HCC treatment in vivo. For this purpose, we reported in this study the first identification of a determining factor of nanocarriers for enhanced HCC therapy in vivo by the use of the previously fabricated pectin-doxorubicin nanoparticles (PDC-NPs) as a typical example, i.e., the natural RBCm was used as a stealth coating of PDC-NPs for the fabrication of biomimetic DDSs, PDC@RBC-NPs via hypotonic dialysis and mechanical co-extrusion methods. Comprehensive in vitro and in vivo evaluation and comparison of the properties and performance of PDC@RBC-NPs and PDC-NPs were performed in terms of colloidal stability, biosafety, drug release profiles, macrophage escape, anti-HCC effect. The resulting PDC@RBC-NPs outperformed PDC-NPs for HCC therapy in vitro and in vivo. Notably, PDC@RBC-NPs-treated BALB/c nude mice showed a significantly smaller final average tumor volume of 613 mm3 after 16 days than the PDC-NPs-treated group with an average value of 957 mm3. Therefore, the PDC@RBC-NPs developed herein showed great potential for clinical transformations due to the facile preparation and superior therapeutic efficiency against HCC. Most importantly, prolonged blood circulation was identified as a determining factor of nanocarriers instead of active targeting for enhanced HCC therapy in vivo, which could be used to direct the future design and development of advanced DDSs with greater therapeutic efficiency for HCC.

Cell membrane-camouflaged nanoparticles as drug carriers for cancer therapy.

The translocation of natural cell membranes to the surface of synthetic nanoparticles, which allows man-made vectors to share merits and functionalities created by nature, has been a hot subject of research in the past decade. The resulting biomimetic nanoparticles not only retain the physicochemical properties of nanomaterials, but also inherit the advantageous functions of source cells. Combined with the preponderances of both synthetic and natural platforms, the optimized biomimetic systems can maximize the drug delivery efficiency. In this review, we first summarize the preparation strategies of the biomimetic systems from the perspective of the correlation between the properties of nanoparticles and cell membranes. Six types of cell membrane-camouflaged nanoparticles are further introduced with an emphasis on their properties and performance. Finally, a concluding remark regarding the primary challenges and opportunities associated with these nanoparticles is presented. STATEMENT OF SIGNIFICANCE: Translocation of natural cell membranes to the surface of synthetic nanoparticles has been repeatedly highlighted in the past decade to endow man-made vectors with merits and functionalities created by nature; therefore, the resulting biomimetic systems not only retain the physicochemical properties of nanomaterials but also inherit the biological functions of source cells for efficient drug delivery. To provide a timely review on this hot and rapidly developing subject of research, this paper summarized recent progress on the cell membrane-camouflaged nanoparticles as drug carriers for cancer therapy, and focused primarily on six different types of cell membrane-coated nanoparticles with an emphasis on the preparation strategies from the perspective of the correlation between the properties of nanoparticles and cell membrane.

Delivery of Liver-Specific miRNA-122 Using a Targeted Macromolecular Prodrug toward Synergistic Therapy for Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) poses a great threat to human health. The elegant combination of gene therapy and chemotherapy by nanocarriers has been repeatedly highlighted to realize enhanced therapeutic efficacy relative to monotreatment. However, the leading strategy to achieve the efficient codelivery of the gene and drug remains the electrostatic condensation with the nucleic acid and the hydrophobic encapsulation of drug molecules by the nanocarriers, which suffers substantially from premature drug leakage during circulation and severe off-target-associated side effects. To address these issues, we reported in this study the codelivery of liver-specific miRNA-122 and anti-cancer drug 5-fluorouracil (5-Fu) using a macromolecular prodrug approach, that is, electrostatic condensation with miRNA-122 using galactosylated-chitosan-5-fluorouracil (GC-FU). The delivery efficacy was evaluated comprehensively in vitro and in vivo. Specifically, the biocompatibility of GC-FU/miR-122 nanoparticles (NPs) was assessed by hemolysis activity analysis, BSA adsorption test, and cell viability assay in both normal liver cells (L02 cells) and endothelial cells. The resulting codelivery systems showed enhanced blood and salt stability, efficient proliferation inhibition of HCC cells, and further induction apoptosis of HCC cells, as well as downregulated expression of ADAM17 and Bcl-2. The strategy developed herein is thus a highly promising platform for an effective codelivery of miRNA-122 and 5-Fu with facile fabrication and great potential for the clinical translation toward HCC synergistic therapy.

Facile fabrication of a novel hybrid nanoparticles by self-assembling based on pectin-doxorubicin conjugates for hepatocellular carcinoma therapy.

Hepatocellular carcinoma (HCC) is one of the greatest public health problems worldwide, and chemotherapy remains the major approach for the HCC treatment. Doxorubicin (DOX) is one of the anthracycline antibiotics but its clinical use is limited due to its severe cardiotoxicity. In this study, novel hybrid nanoparticles by self-assembling based on pectin-doxorubicin conjugates (PDC-NPs) were fabricated for HCC treatment. The stabilized structure of the PDC-NPs was characterized by methylene blue absorption, the size, zeta potential and the morphology, which was investigated by Zetasizer nanoparticle analyzer and transmission electron microscope (TEM), of nanoparticles. The PDC-NPs achieved a sustained and prolonged release ability, which was illustrated with in vitro drug release profiles, anti-cell proliferation study, cellular uptake assay and in vivo pharmacokinetics analysis. Biocompatibility of the PDC-NPs was assessed with bovine serum albumin (BSA) adsorption test, hemolysis activity examination and viability evaluation of human umbilical vein endothelial cells. Importantly, in vivo studies of the PDC-NPs, which were performed in the athymic BALB/c nude mice, demonstrated that the PDC-NPs significantly reduced the lethal side effect of DOX. Additionally, the H&E staining and serum biochemistry study further confirmed the excellent biological security of the PDC-NPs.

Fabrication and characterization of a novel self-assembling micelle based on chitosan cross-linked pectin-doxorubicin conjugates macromolecular pro-drug for targeted cancer therapy.

Cancer is one of the leading causes of morbidity and mortality worldwide. Doxorubicin is one of the most effective anticancer drugs approved by FDA. However, like all the other anticancer drugs, the efficacy of DOX is associated with high systemic toxicity to healthy tissues. In this study, chitosan cross-linked pectin-doxorubicin conjugates macromolecular pro-drug (CS-PDC-M) was prepared to enhance the therapeutic effects on liver cancer. CS-PDC-M was characterized in terms of size, size distribution, zeta potential, scanning electron microscope (SEM) and drug loading content. The CS-PDC-M achieved prolonged releasing ability was demonstrated by the in vitro drug release and in vitro cellular uptake assay. Biocompatibility of CS-PDC-M was screened by hemolysis activity examination, BSA adsorption test and cell viability evaluation in endothelial cells and LO2 cells. The CS-PDC-M achieved significantly high antitumor efficiency and targeting efficiency, which was demonstrated by the in vitro MTT assay and cellular targeting assay toward HepG2 cells, MCF-7 cells and A549 cells. The in vivo antitumor efficacy of CS-PDC-M was studied in athymic BALB/c nude mice bearing HepG2 cell xenografts. The organ damage assays of CS-PDC-M was studied in SD rats. Compared with that of free DOX and PDC-M, the CS-PDC-M exhibited higher antitumor efficacy and lower toxicity, implying that CS-PDC-M is a highly promising drug delivery system for hepatocellular carcinoma treatment.

In vitro and in vivo evaluation of macromolecular prodrug GC-FUA based nanoparticle for hepatocellular carcinoma chemotherapy.

A novel type of macromolecular prodrug delivery system is reported in this research. The N-galactosylated-chitosan-5-fluorouracil acetic acid conjugate (GC-FUA) based nanoparticle delivery system was evaluated in vitro and in vivo. Biocompatibility of GC-FUA-NPs was screened by BSA adsorption test and hemolysis activity examination in vitro. Cytotoxicity and cellular uptake study in HepG2 and A549 cells demonstrated that compared to free 5-Fu, the GC-FUA-NPs play great function in killing cancer cells for the cell endocytosis mediated by asialoglycoprotein receptor (ASGPR), which overexpresses on the cell surface. Pharmacokinetics study further illustrated that the drug-loaded nanoparticles has a much longer half-time than free 5-Fu in blood circulation in Sprague-Dawley (SD) rats. Tissue distribution was investigated in Kunming mice, and the result showed that the GC-FUA-NPs have a long circulation effect. The obtained data suggested that GC-FUA-NP is a very promising drug delivery system for efficient treatment of hepatocellular carcinoma.