Enhanced Delivery of Plasmid Encoding Interleukin-12 Gene by Diethylene Triamine Penta-Acetic Acid (DTPA)-Conjugated PEI Nanoparticles

Targeted delivery of interleukin-12 plasmid into HepG2 cells through folic acid conjugated graphene oxide nanocarrier

Successful gene therapy relies on carriers to transfer genetic materials with high efficiency and low toxicity in a targeted manner. To enhance targeted cell binding and uptake, we developed and synthesized a new gene delivery vector based on graphene oxide (GO) modified by branched polyethyleneimine (BPEI) and folic acid (FA). The GO-PEI-FA nanocarriers exhibit lower toxicity compared to unmodified PEI, as well as having the potential to efficiently condense and protect pDNA. Interestingly, increasing the polymer content in the polyplex formulation improved plasmid transfer ability. Substituting graphene oxide for PEI at an N/P ratio of 10 in the HepG2 and THP1 cell lines improved hIL-12 expression by up to approximately eightfold compared to simple PEI, which is twice as high as GO-PEI-FA in Hek293 at the same N/P ratio. Therefore, the GO-PEI-FA described in this study may serve as a targeting nanocarrier for the delivery of the hIL-12 plasmid into cells overexpressing folic acid receptors, such as those found in hepatocellular carcinoma.

A Study of Glutathione-Responsive Dual-Drug-Loaded Nanoparticles in Anti-Osteosarcoma Treatment

We connected polyglutamic acid and methotrexate (MTX) through disulfide bonds to prepare glutathione-responsive nanoparticles (MTX NPs) and encapsulated doxorubicin (DOX) to obtain dual drug-loaded NPs (DOX/MTX NPs) (Fig. 1). The appearance of the carbonyl stretching vibration peak at approximately 1640 cm−1 in the results of the infrared spectrum proved the successful synthesis of three kinds of nanoparticles (NPs) with different feeding ratios. The particle sizes of NPs with different feeding ratios were 100–200 nm, and the encapsulation of DOX slightly increased the size, while the surface charge was always negative. The release of MTX at 10 mM glutathione (GSH) was as high as 91.45%, and that of DOX was 89.44%, suggesting that the breakage of disulfide bonds leads to the disintegration of NPs. The results of the cell experiment showed that the encapsulation of DOX effectively increased toxicity and side effects in 143B cells and significantly induced cell apoptosis, and the inhibition of the migration rate increased as the feeding ratio increased. In animal experiments, DOX/MTX NPs significantly induced tumor cell apoptosis and inhibited cell proliferation and tumor growth. The nanoparticles had excellent tumor-targeting properties. Tumor-targeted NPs with the combined action of the two drugs provided a good strategy for the efficient and precise treatment of osteosarcoma.

Iron oxide nanoparticle targeted chemo-immunotherapy for triple negative breast cancer

Triple negative breast cancer is difficult to treat effectively, due to its aggressiveness, drug resistance, and lack of the receptors required for hormonal therapy, particularly at the metastatic stage. Here, we report the development and evaluation of a multifunctional nanoparticle formulation containing an iron oxide core that can deliver doxorubicin, a cytotoxic agent, and polyinosinic:polycytidylic acid (Poly IC), a TLR3 agonist, in a targeted and simultaneous fashion to both breast cancer and dendritic cells. Endoglin-binding peptide (EBP) is used to target both TNBC cells and vasculature epithelia. The nanoparticle demonstrates favorable physicochemical properties and a tumor-specific targeting profile. The nanoparticle induces tumor apoptosis through multiple mechanisms including direct tumor cell killing, dendritic cell-initiated innate and T cell-mediated adaptive immune responses. The nanoparticle markedly inhibits tumor growth and metastasis and substantially extends survival in an aggressive and drug-resistant metastatic mouse model of triple negative breast cancer (TNBC). This study points to a promising platform that may substantially improve the therapeutic efficacy for treating metastatic TNBC.

Protective and therapeutic effects of ethanolic extract of Nasturtium officinale (watercress) and vitamin E against bleomycin-induced pulmonary fibrosis in rats

Background and purpose

Pulmonary fibrosis is a chronic disease of the lungs caused by inflammation, species of reactive oxygen, and immune defects. Antioxidant properties of Nasturtium officinale has been reported in some studies. Therefore, the objective of the current study was to evaluate the effect of ethanolic extract of Nasturtium officinale (EENO) on bleomycin (BLM)-induced lung fibrosis in rats.

Experimental approach

Forty adult male Wistar rats (180-220 g) were randomly divided into 5 experimental groups. Normal control, BLM control received a single dose of BLM (6 IU/kg) intratracheally only on the first day, EENO + BLM group received EENO (500 mg/kg) one week before intratracheal BLM instillation and two weeks afterward, BLM + EENO group and BML + vitamin E group received EENO (500 mg/kg) and vitamin E (500 mg/kg) half-hour after BLM installation, respectively. The animals were sacrificed on day 22. Change in body weight, lung index, serum level of malondialdehyde (MDA) and nitric oxide (NO) metabolite, lung tissue hydroxyproline content and lung pathology were assessed.

Findings/Results

Pre- or post-treatment with EENO attenuated pulmonary fibrosis as evidenced by normalized lung index, improved histological changes and inhibited collagen deposition (hydroxyproline) in the animal lung. EENO also decreased MDA and NO metabolite release in comparison to the BLM control. vitamin E (500 mg/ kg) also significantly inhibited the BLM-induced lung toxicity.

Conclusions and implications

EENO can prevent BLM-induced lung fibrosis in rats via antioxidant activities. However, more studies are needed to elicit the exact mechanism of this effect.

Localized Interleukin-12 for Cancer Immunotherapy

Interleukin-12 (IL-12) is a potent, pro-inflammatory type 1 cytokine that has long been studied as a potential immunotherapy for cancer. Unfortunately, IL-12's remarkable antitumor efficacy in preclinical models has yet to be replicated in humans. Early clinical trials in the mid-1990's showed that systemic delivery of IL-12 incurred dose-limiting toxicities. Nevertheless, IL-12's pleiotropic activity, i.e., its ability to engage multiple effector mechanisms and reverse tumor-induced immunosuppression, continues to entice cancer researchers. The development of strategies which maximize IL-12 delivery to the tumor microenvironment while minimizing systemic exposure are of increasing interest. Diverse IL-12 delivery systems, from immunocytokine fusions to polymeric nanoparticles, have demonstrated robust antitumor immunity with reduced adverse events in preclinical studies. Several localized IL-12 delivery approaches have recently reached the clinical stage with several more at the precipice of translation. Taken together, localized delivery systems are supporting an IL-12 renaissance which may finally allow this potent cytokine to fulfill its considerable clinical potential. This review begins with a brief historical account of cytokine monotherapies and describes how IL-12 went from promising new cure to ostracized black sheep following multiple on-study deaths. The bulk of this comprehensive review focuses on developments in diverse localized delivery strategies for IL-12-based cancer immunotherapies. Advantages and limitations of different delivery technologies are highlighted. Finally, perspectives on how IL-12-based immunotherapies may be utilized for widespread clinical application in the very near future are offered.

Cholesterol-conjugated PEGylated PAMAM as an efficient nanocarrier for plasmid encoding interleukin-12 immunogene delivery toward colon cancer cells

IL-12 is a pleiotropic cytokine, which shows an ideal applicant for tumor immunotherapy, because of its features of creating an interconnection between innate (NK cells) and adaptive (cytotoxic T lymphocyte) immunity. IL-12 gene therapy is a useful technique to deliver an immune-modulatory gene directly into tumor site thereby limiting the adverse effects of systemic administration of IL-12 proteins. One of the most largely investigated non-viral gene carriers is polyamidoamine (PAMAM). In the current research, 5 and 3% of PAMAM primary amines were substituted to transmit the plasmid encoding IL-12 gene to cells by cholesteryl chloroformate and alkyl-PEG, respectively. The features of modified PAMAMs containing size and surface charge density, cytotoxicity, and transfection efficiency were investigated in colon cancer cells. in vitro experiment showed that this modified carrier with average size of about 160 nm and zeta potential of 30 mV was able to increase the level of IL-12 production up to two folds as compared to that of the unmodified PAMAM. Improvement of the polymer hydrophobic balance along with of the modulation of the surface positive charge could provide an efficient and safe non-viral IL-12 gene for colon cancer immunogene therapy.

Preparation, characterization, and transfection efficiency of low molecular weight polyethylenimine-based nanoparticles for delivery of the plasmid encoding CD200 gene

Various strategies have been utilized to improve both gene transfer efficiency and cell-induced toxicity of polyethylenimine (PEI), the most extensively investigated cationic polymeric vector. In this study, we sought to enhance transfection efficiency of low molecular weight PEI (LMW PEI) while maintaining its low toxicity by cross-linking LMW PEI via succinic acid linker. These modifications were designed to improve the hydrophilic–hydrophobic balance of the polymer, by enhancing the buffering capacity and maintaining low cytotoxic effects of the final conjugate. Decreased expression of CD200 in the central nervous system has been considered as one of the proposed mechanisms associated with neuroinflammation in multiple sclerosis; therefore, we selected plasmid-encoding CD200 gene for transfection using the modified PEI derivatives. Dynamic light scattering experiments demonstrated that the modified PEIs were able to condense plasmid DNA and form polyplexes with a size of approximately 130 nm. The highest level of CD200 expression was achieved at a carrier to plasmid ratio of 8, where the expression level was increased by 1.5 fold in the SH-SY5Y cell line, an in vitro model of neurodegenerative disorders. Furthermore, the results of in vivo imaging of the LMW PEI-based nanoparticles in the mouse model of multiple sclerosis revealed that fluorescently labeled plasmid encoding CD200 was distributed from the injection site to various tissues and organs including lymph nodes, liver, brain, and finally, kidneys. The nanoparticles also showed the ability to cross the blood–brain barrier and enter the periventricular area.