Gestational diabetes mellitus (GDM) is a pregnancy-specific disease characterized by impaired glucose tolerance during pregnancy. Although diagnosis and clinical management have improved significantly, there are still areas where therapeutic approaches need further improvement. Recent evidence suggests that CCL2, a chemokine involved in immunoregulatory and inflammatory processes, is closely related to GDM. However, the potential value for clinical therapeutic applications and the mechanism of CCL2 in adipose tissue macrophages (ATMs) of GDM remain to be elucidated. Here, we found that CCL2 was enriched in macrophages of the visceral adipose tissue from GDM women and HFD-induced GDM mice. The combination of in vitro and in vivo experiments showed that Ccl2 silencing inhibited the inflammatory response of macrophage by blocking calcium transport between ER and mitochondria and reducing excessive ROS generation. Additionally, the ATS-9R/siCcl2 oligopeptide complex targeting adipose tissue was created. Under the delivery of ATS-9R peptide, Ccl2 siRNA is expressed in ATMs, which reduces inflammation in adipose tissue and, as a result, mitigates insulin resistance. All of these findings point to the possibility that the ATS-9R/siCcl2 complex, which targets adipose tissue, is able to reduce insulin resistance in GDM and the inflammatory response in macrophages. The ATS-9R/siCcl2 oligopeptide complex targeting adipose tissue seems to be a viable treatment for GDM pregnancies.

Introduction: Blood-brain barrier with strictly controlled activity participates in a coordinated transfer of bioactive molecules from the blood to the brain. Among different delivery approaches, gene delivery is touted as a promising strategy for the treatment of several nervous system disorders. The transfer of exogenous genetic elements is limited by the paucity of suitable carriers. As a correlate, designing high-efficiency biocarriers for gene delivery is challenging. This study aimed to deliver pEGFP-N1 plasmid into the brain parenchyma using CDX-modified chitosan (CS) nanoparticles (NPs). Methods: Herein, we attached CDX, a 16 amino acids peptide, to the CS polymer using bifunctional polyethylene glycol (PEG) formulated with sodium tripolyphosphate (TPP), by ionic gelation method. Developed NPs and their nanocomplexes with pEGFP-N1 (CS-PEG-CDX/pEGFP) were characterized using DLS, NMR, FTIR, and TEM analyses. For in vitro assays, a rat C6 glioma cell line was used for cell internalization efficiency. The biodistribution and brain localization of nanocomplexes were studied in a mouse model after intraperitoneal injection using in vivo imaging and fluorescent microscopy. Results: Our results showed that CS-PEG-CDX/pEGFP NPs were uptaken by glioma cells in a dose-dependent manner. In vivo imaging revealed successful entry into the brain parenchyma indicated with the expression of green fluorescent protein (GFP) as a reporter protein. However, the biodistribution of developed NPs was also evident in other organs especially the spleen, liver, heart, and kidneys. Conclusion: Based on our results, CS-PEG-CDX NPs can provide a safe and effective nanocarrier for brain gene delivery into the central nervous system (CNS).

In recent decades, cancer immunotherapy has demonstrated considerable clinical advantages in cancer therapy. Particularly, the use of immunological gene therapy continues to grow in this field. Macrophage Inflammatory Protein 3 Beta (MIP-3β) has emerged as a potential immunomodulator for anti-cancer treatments by enhancing the interaction among immune responses. In this study, we demonstrate an innovative targeted gene delivery system based on a self-assembly technique with 1,2-Dioleoyl-3-trimethylammonium-propane (DOTAP), Methoxy poly(ethylene glycol)-poly(lactide) (MPEG-PLA), and folic acid modified poly(ethylene glycol)-poly(ε-caprolactone) (FA-PEG-PCL) (FDMCA). Results showed that the expression of MIP-3β was up-regulated in cancer cells following the transfection with FDMCA-pMIP-3β, in comparison with cells transfected with DMCA-pMIP-3β. The supernatants collected from cancer cells transfected with FDMCA-pMIP-3β and DMCA-pMIP-3β both instigate dendritic cell maturation, M1 polarisation of macrophages, activation and presentation of cytotoxicity in lymphocytes. Moreover, tumor growth and metastasis were markedly inhibited following the administration of the FDMCA-pMIP-3β complex in both subcutaneous and pulmonary metastasis mice models, which is attributed to reduced angiogenesis, enhanced cancer cell apoptosis, and suppressed proliferation by activation of the immune system. Our study suggests that the MIP-3β plasmid and FDMCA complex provide a new approach for the treatment of breast cancer.

Cationic nanocarriers are reported to induce cell necrosis, especially in the lungs upon systemic administration. The release of damage-associated molecular patterns, such as mitochondrial DNA from the injured cell may result in the inflammatory toxicity of the nanocarrier, which has largely limited its clinical application. Partial blocking of the surface charge of cationic nanocarriers might improve their safety. As hyaluronan (HA) is an anionic polysaccharide that is widely used for specific binding to CD44 to improve the cellular uptake efficiency in tumor-targeting therapy, in this study, we modified cationic liposomes (LP) with the negatively charged HA at a mass ratio of 10% to prepare targeted HA-modified cationic liposomes (HALP). Cationic liposomes modified with hyaluronan showed significantly less cytotoxicity due to the blockage of their surface charge than the unmodified liposomes. In addition, HA modification helped to reduce cell necrosis in lung tissue and reduced the amount of mitochondria subsequently released, which alleviated pulmonary inflammation in mice. HA-modified liposomes also improved the survival of mice injected with a fatal dose of HALP compared with mice injected with cationic LP. In addition, both serological biochemical analysis and histological examination proved that a liposome modified with HA is a safer carrier for systemic administration than an unmodified liposome. Furthermore, HALP/survivin exhibited an enhanced antitumor effect by inhibiting tumor growth and promoting tumor cell apoptosis compared with the unmodified LP group. In conclusion, compared to the properties of cationic liposomes, liposomes modified with 10% HA (HALP) might be gene vectors with lower toxicity and higher tumor targeting efficiency.

Integrin αvβ3 is restrictedly expressed on angiogenic blood vessels and tumour cells. It plays a key role in angiogenesis for tumour growth and metastasis. RGD peptide can specifically recognise the integrin αvβ3, which serves as targeted molecular for anti-angiogenesis strategies. Therefore, the targeted delivery of therapeutics by RGD peptide-based non-viral vectors to tumour vasculature and tumour cells is recognised as a promising approach for treating cancer. In this review, we illustrate the interaction between RGD peptide and integrin αvβ3 from different perspectives. Meanwhile, four types of RGD peptide-based non-viral gene delivery vectors for cancer therapy, including RGD-based cationic polymers, lipids, peptides and hybrid systems, are summarised. The aim is to particularly highlight the enhanced therapeutic effects and specific targeting ability exhibited by these vectors for cancer gene therapy both in vitro and in vivo.

Anti-microRNA-155 (anti-miR-155), an oligonucleotide with a complimentary sequence to microRNA-155, holds great promise for lung cancer therapy, and thus some cationic materials have been used to deliver anti-miR-155 into lung tumors. Although the gene delivery capacity in vitro was favorable, the application in vivo was limited by rapid removal and significant cytotoxicity, which were mainly caused by the positive charge of the gene complexes. Therefore, it was necessary to develop a novel carrier to decrease the positive charge and increase the gene delivery capacity into the tumor site. In this paper, biodegradable poly(ester amine) (PEA) was used to condense anti-miR-155 into PEA/anti-miR-155 complexes, and natural anionic polysaccharide hyaluronic acid (HA) was modified with a lung tumor cell targeting peptide and then coated on the surface of gene complexes. The formed hyaluronic acid shielding, PEA/anti-miR-155/HA-peptide complexes were monodispersed, and the particle size and zeta potential were 362.7 nm and -10.17 mV, respectively. In addition, the PEA/anti-miR-155/HA-peptide complexes had good biocompatibility and stability in vitro, and the lung tumor growth inhibitions of PEA/anti-miR-155/HA-peptide in vitro and in vivo were also excellent. The PEA/anti-miR-155/HA-peptide complexes play an active role in tumor growth inhibition and could be useful for lung cancer therapy.

Biodegradable polyamines have long been studied as potential recombinant viral gene vectors. Spermine (SPE) is an endogenous tetra-amine with excellent biocompatibility yet poor gene condensation capacity. We have previously synthesized a polyspermine based on SPE and poly(ethylene glycol) (PEG) diacrylate (SPE-alt-PEG) for enhanced transfection performance, but the synthesized SPE-alt-PEG still lacked specificity towards cancer cells. In this study, folic acid (FA) was incorporated into SPE-alt-PEG to fabricate a targeted gene delivery vector (FA-SPE-PEG) via an acylation reaction. FA-SPE-PEG exhibited mild cytotoxicity in both cancer cells and normal cells. FA-SPE-PEG possessed higher transfection efficiency than PEI 25 K and Lipofectamine(®) 2000 in two tested cancer cell lines at functional weight ratios, and its superiority over untargeted SPE-alt-PEG was prominent in cells with overexpressed folate receptors (FRs). Moreover, in vivo delivery of green fluorescent protein (GFP) with FA-SPE-PEG resulted in highest fluorescent signal intensity of all investigated groups. FA-SPE-PEG showed remarkably enhanced specificity towards cancer cells both in vivo and in vitro due to the interaction between FA and FRs. Taken together, FA-SPE-PEG was demonstrated to be a prospective targeted gene delivery vector with high transfection capacity and excellent biocompatibility.

RGD tripeptide is a specific, high-affinity ligand for integrin, which is highly expressed in cancer cells. We previously reported that cRGD chemically modified AAV2 (AAV2(N587+1/azido+RGD)) showed significantly enhanced infectivity compared to RGD genetically inserted AAV2 (AAV2(N587+RGD)) (10.1016/j.biomaterials.2015.11.066) [1]. Herein we provide the binding ability analysis of RGD modified AAV2 and U87 cell by flow cytometry and the theoretical working model of RGD-αvβ3 integrin interaction.

In this report, two biodegradable star-shaped polyasparamide derivatives and four analogues modified with either mannose or folic acid moiety for preferential targeting of a difficult-to-transfect immune cell type, i.e., macrophage, have been synthesized. Each of the prepared star polymers complexes with plasmid DNA to form nanosized particles featuring a core-shell-like morphology. Mannose or folate functionalized star polymers can greatly improve the transfection performance on a macrophage cell line RAW 264.7. As a result, a combination of targeting ligand modification and topological structures of gene carriers is a promising strategy for immune cells-based gene therapy.

To develop a chitosan-based nonviral gene carrier capable of delivering genes specifically into hepatoma cells, a bifunctional peptide composed of the TAT (transactivator of transcription) peptide and luteinizing hormone-releasing hormone (LHRH) was conjugated with low molecular weight chitosan, resulting in a TAT-LHRH-chitosan conjugate (TLC). TLC/DNA nanoparticles (TLCDNPs) were characterized by agarose gel retardation, atomic force microscopy, and dynamic light scattering analysis. In vitro targeting specificity and transfection efficiency were analyzed with a GE IN Cell Analyzer 2000 High-Content Cellular Analysis System. The results demonstrated that TLC had stronger DNA condensing power than unmodified chitosan, and that TLCDNPs were of roughly round shape with average diameter of 70-85 nm and zeta potential of +30 mV and were relatively stable in solution. The in vitro study demonstrated TLC was highly selective for hepatoma cells and essentially nontoxic.