Enhanced Anti-tumor of Pep-1 Modified Superparamagnetic Iron Oxide/PTX Loaded Polymer Nanoparticles

Construction of GPC3-modified Lipopolymer SiRNA Delivery System

BACKGROUND

Gene therapy has been widely concerned because of its unique therapeutic mechanism. However, due to the lack of safe and effective carries, it has not been widely used in clinical practice. Glypican 3 (GPC3) is a highly specific proteoglycan for hepatocellular carcinoma and is a potential diagnostic and therapeutic target for hepatocellular carcinoma. Herein, to monitor the effect of gene therapy and enhance the transfection efficiency of gene carriers, GPC3-modified lipid polyethyleneimine-modified superparamagnetic nanoparticle (GLPS), a type of visualized carrier for siRNA (small-interfering RNA) targeting the liver, was prepared.

METHODS

We performed in vitro gene silencing, cytotoxicity, and agarose gel electrophoresis to identify the optimal GLPS formulation. In vitro MRI and Prussian blue staining verified the liver-targeting function of GLPS. We also analyzed the biocompatibility of GLPS by co-culturing with rabbit red blood cells. Morphological changes were evaluated using HE staining.

RESULTS

The GLPS optimal formulation consisted of LPS and siRNA at a mass ratio of 25:1 and LPS and DSPE-PEG-GPC3 at a molar ratio of 2:3. GLPS exhibited evident liver-targeting function. In vitro, we did not observe morphological changes in red blood cells or hemolysis after co-culture. In vivo, routine blood analysis revealed no abnormalities after GLPS injection. Moreover, the tissue morphology of the kidney, spleen, and liver was normal without injury or inflammation.

CONCLUSION

GLPS could potentially serve as an effective carrier for liver-targeted MRI monitoring and siRNA delivery.

Nanobiomaterials: exploring mechanistic roles in combating microbial infections and cancer

The initiation of the "nanotechnology era" within the past decade has been prominently marked by advancements in biomaterials. This intersection has opened up numerous possibilities for enhancing the detection, diagnosis, and treatment of various illnesses by leveraging the synergy between biomaterials and nanotechnology. The term "nano biomaterials" referring to biomaterials featuring constituent or surface feature sizes below 100 nm, presents a realm of extraordinary materials endowed with unique structures and properties. Beyond addressing common biomedical challenges, these nano biomaterials contribute unprecedented insights and principles that enrich our understanding of biology, medicine, and materials science. A critical evaluation of recent technological progress in employing biomaterials in medicine is essential, along with an exploration of potential future trends. Nanotechnology breakthroughs have yielded novel surfaces, materials, and configurations with notable applications in the biomedical domain. The integration of nanotechnology has already begun to enhance traditional biomedical practices across diverse fields such as tissue engineering, intelligent systems, the utilization of nanocomposites in implant design, controlled release systems, biosensors, and more. This mini review encapsulates insights into biomaterials, encompassing their types, synthesis methods, and the roles of organic and inorganic nanoparticles, elucidating their mechanisms of action. Furthermore, the focus is squarely placed on nano biomaterials and their versatile applications, with a particular emphasis on their roles in anticancer and antimicrobial interventions. This review underscores the dynamic landscape of nanotechnology, envisioning a future where nano biomaterials play a pivotal role in advancing medical applications, particularly in combating cancer and microbial infections.

Superparamagnetic Nanocrystals Clustered Using Poly(ethylene glycol)-Crosslinked Amphiphilic Copolymers for the Diagnosis of Liver Cancer

Superparamagnetic iron oxide (SPIO) nanocrystals have been extensively studied as theranostic nanoparticles to increase transverse (T2) relaxivity and enhance contrast in magnetic resonance imaging (MRI). To improve the blood circulation time and enhance the diagnostic sensitivity of MRI contrast agents, we developed an amphiphilic copolymer, PCPZL, to effectively encapsulate SPIO nanocrystals. PCPZL was synthesized by crosslinking a polyethylene glycol (PEG)-based homobifunctional linker with a hydrophobic star-like poly(ε-benzyloxycarbonyl-L-lysine) segment. Consequently, it could self-assemble into shell-crosslinked micelles with enhanced colloidal stability in bloodstream circulation. Notably, PCPZL could effectively load SPIO nanocrystals with a high loading capacity of 66.0 ± 0.9%, forming SPIO nanoclusters with a diameter of approximately 100 nm, a high cluster density, and an impressive T2 relaxivity value 5.5 times higher than that of Resovist®. In vivo MRI measurements highlighted the rapid accumulation and contrast effects of SPIO-loaded PCPZL micelles in the livers of both healthy mice and nude mice with an orthotopic hepatocellular carcinoma tumor model. Moreover, the magnetic micelles remarkably enhanced the relative MRI signal difference between the tumor and normal liver tissues. Overall, our findings demonstrate that PCPZL significantly improves the stability and magnetic properties of SPIO nanocrystals, making SPIO-loaded PCPZL micelles promising MRI contrast agents for diagnosing liver diseases and cancers.

Therapeutic applications of nanobiotechnology

Nanobiotechnology, as a novel and more specialized branch of science, has provided a number of nanostructures such as nanoparticles, by utilizing the methods, techniques, and protocols of other branches of science. Due to the unique features and physiobiological characteristics, these nanostructures or nanocarriers have provided vast methods and therapeutic techniques, against microbial infections and cancers and for tissue regeneration, tissue engineering, and immunotherapies, and for gene therapies, through drug delivery systems. However, reduced carrying capacity, abrupt and non-targeted delivery, and solubility of therapeutic agents, can affect the therapeutic applications of these biotechnological products. In this article, we explored and discussed the prominent nanobiotechnological methods and products such as nanocarriers, highlighted the features and challenges associated with these products, and attempted to conclude if available nanostructures offer any scope of improvement or enhancement. We aimed to identify and emphasize the nanobiotechnological methods and products, with greater prospect and capacity for therapeutic improvements and enhancements. We found that novel nanocarriers and nanostructures, such as nanocomposites, micelles, hydrogels, microneedles, and artificial cells, can address the associated challenges and inherited drawbacks, with help of conjugations, sustained and stimuli-responsive release, ligand binding, and targeted delivery. We recommend that nanobiotechnology, despite having few challenges and drawbacks, offers immense opportunities that can be harnessed in delivering quality therapeutics with precision and prediction. We also recommend that, by exploring the branched domains more rigorously, bottlenecks and obstacles can also be addressed and resolved in return.

Polydopamine-based loaded temozolomide nanoparticles conjugated by peptide-1 for glioblastoma chemotherapy and photothermal therapy

Purpose: Nanoparticles (NPs) of the polydopamine (PDA)-based,loaded with temozolomide (TMZ) and conjugated with Pep-1 (Peptide-1) as a feasible nano-drug delivery system were constructed and utilized for chemotherapy (CT) and photothermal therapy (PTT) of glioblastoma (GBM). Method: PDA NPs were synthesized from dopamine (DA) hydrochloride and reacted with TMZ to obtain the PDA-TMZ NPs and then the PDA NPs and the PDA-TMZ NPs were conjugated and modified by Pep-1 to obtain the Pep-1@PDA NPs and Pep-1@PDA-TMZ NPs via the Schiff base reaction (SBR), respectively.Their dimensions, charge, and shape were characterized by dynamic light scattering (DLS) and scanning electron microscope (SEM). The assembly of TMZ was verified by Fourier-transform infrared spectroscopy (FT-IR) and ultraviolet and visible spectroscopy (UV-Vis). The biostability of both the nanocarrier and the synthetic NPs were validated using water and fetal bovine serum (FBS). The antitumor activities of the PDA-TMZ NPs and Pep-1@PDA-TMZ NPs were verified in U87 cells and tumor-bearing nude mice. Results: The prepared PDA NPs, PDA-TMZ NPs, Pep-1@PDA NPs, and Pep-1@PDA-TMZ NPs were regular and spherical, with dimension of approximately 122, 131, 136, and 140 nm, respectively. The synthetic nanoparticles possessed good dispersity, stability,solubility, and biocompatibility. No obvious toxic side effects were observed, and the loading rate of TMZ was approximately 50%.In vitro research indicated that the inhibition ratio of the Pep-1@PDA-TMZ NPs combined with 808 nm laser was approximately 94% for U87 cells and in vivo research was approximately 77.13%, which was higher than the ratio of the other groups (p < 0.05). Conclusion: Pep-1 was conjugated and modified to PDA-TMZ NPs, which can serve as a new targeted drug nano-delivery system and can offer a CT and PTT integration therapy against GBM. Thus, Pep-1@PDA-TMZ NPs could be a feasible approach for efficient GBM therapy, and further provide some evidence and data for clinical transformation so that gradually conquer GBM.

Polydopamine-based loaded temozolomide nanoparticles conjugated by peptide-1 for glioblastoma chemotherapy and photothermal therapy

Purpose: Nanoparticles (NPs) of the polydopamine (PDA)-based,loaded with temozolomide (TMZ) and conjugated with Pep-1 (Peptide-1) as a feasible nano-drug delivery system were constructed and utilized for chemotherapy (CT) and photothermal therapy (PTT) of glioblastoma (GBM).

Method: PDA NPs were synthesized from dopamine (DA) hydrochloride and reacted with TMZ to obtain the PDA-TMZ NPs and then the PDA NPs and the PDA-TMZ NPs were conjugated and modified by Pep-1 to obtain the Pep-1@PDA NPs and Pep-1@PDA-TMZ NPs via the Schiff base reaction (SBR), respectively.Their dimensions, charge, and shape were characterized by dynamic light scattering (DLS) and scanning electron microscope (SEM). The assembly of TMZ was verified by Fourier-transform infrared spectroscopy (FT-IR) and ultraviolet and visible spectroscopy (UV-Vis). The biostability of both the nanocarrier and the synthetic NPs were validated using water and fetal bovine serum (FBS). The antitumor activities of the PDA-TMZ NPs and Pep-1@PDA-TMZ NPs were verified in U87 cells and tumor-bearing nude mice.

Results: The prepared PDA NPs, PDA-TMZ NPs, Pep-1@PDA NPs, and Pep-1@PDA-TMZ NPs were regular and spherical, with dimension of approximately 122, 131, 136, and 140 nm, respectively. The synthetic nanoparticles possessed good dispersity, stability,solubility, and biocompatibility. No obvious toxic side effects were observed, and the loading rate of TMZ was approximately 50%.In vitro research indicated that the inhibition ratio of the Pep-1@PDA-TMZ NPs combined with 808 nm laser was approximately 94% for U87 cells and in vivo research was approximately 77.13%, which was higher than the ratio of the other groups (p &lt; 0.05).

Conclusion: Pep-1 was conjugated and modified to PDA-TMZ NPs, which can serve as a new targeted drug nano-delivery system and can offer a CT and PTT integration therapy against GBM. Thus, Pep-1@PDA-TMZ NPs could be a feasible approach for efficient GBM therapy, and further provide some evidence and data for clinical transformation so that gradually conquer GBM.

99mTc-labeled peptide targeting interleukin 13 receptor α 2 for tumor imaging in a cervical cancer mouse model

OBJECTIVE

Pep-1 (CGEMGWVRC) can potently bind to interleukin 13 receptor α 2 (IL-13Rα2), a tumor-restricted receptor found to be expressed in various malignancies. In this study, we intended to prepare a ^99mTc-labeled probe and evaluate its in vivo tumor accumulation properties in a cervical cancer xenograft model.

METHODS

The Pep-1 was designed and radiolabeled with ^99mTc by conjugation with mercaptoacetyl-triglycine (MAG₃). The labeling yield, radiochemical purity and stability were characterized in vitro. Cell uptake assays and fluorescence imaging were conducted for qualitative and quantitative evaluation of the specificity and affinity of Pep-1. Flow cytometry and tissue immunofluorescence were used to confirm the IL-13Rα2 expression in cervical cancer. Biodistribution and in vivo imaging were performed periodically to evaluate the imaging value of ^99mTc-MAG₃-Pep-1 in cervical cancer xenograft model.

RESULTS

^99mTc-MAG₃-Pep-1 was successfully prepared with a high labeling yield and radiochemical purity (> 95%). Specific cell uptake was demonstrated by scramble control and unlabeled MAG₃-Pep-1 blockade. Flow cytometry and tissue immunofluorescence also confirmed the mild IL-13Rα2 expression of HeLa. In the gamma imaging study and biodistribution, the tumors were imaged clearly at 2-6 h after injection of ^99mTc-MAG₃-Pep-1 and the accumulation of ^99mTc-MAG₃-Pep-1 in tumor was significantly higher than that in the blocking and scramble controls, demonstrating ligand-receptor binding specificity.

CONCLUSIONS

This work demonstrated that ^99mTc-MAG₃-Pep-1 can bind to cervical cancer with high affinity and specificity. MAG₃-Pep-1 may be a prospective precursor for IL-13Rα2-expressing cancer therapy.

Source and exploration of the peptides used to construct peptide-drug conjugates

Peptide-drug conjugates (PDCs) are a class of novel molecules widely designed and synthesized for delivering payload drugs. The peptide part plays a vital role in the whole molecule, because they determine the ability of the molecules to penetrate the membrane and target to the specific targets. Here, we introduce the source of different kinds of cell-penetrating peptides (CPPs) and cell-targeting peptides (CTPs) that have been used or could be used in constructing PDCs as well as their latest application in delivering drugs. What's more, the approaches of developing CPPs and CTPs and the techniques to discover novel peptides are focused on and summarized in the review. This review aims to help relevant researchers fast understand the research status of peptides in PDCs and carry forward the process of novel peptides discovery.

The Application of Peptides in Glioma: a Novel Tool for Therapy

BACKGROUND

Glioma is the most aggressive and lethal tumor of the central nervous system. Owing to the cellular heterogeneity, the invasiveness, and blood-brain barrier (BBB), current therapeutic approaches, such as chemotherapy and radiotherapy, are poorly to obtain great anti-tumor efficacy. However, peptides, a novel type of therapeutic agent, displayed excellent ability in the tumor, which becomes a new molecule for glioma treatment.

METHOD

We review the current knowledge on peptides for the treatment of glioma through a PubMed-based literature search.

RESULTS

In the treatment of glioma, peptides can be used as (i) decoration on the surface of the delivery system, facilitating the distribution and accumulation of the anti-tumor drug in the target site;(ii) anti-tumor active molecules, inhibiting the growth of glioma and reducing solid tumor volume; (iii) immune-stimulating factor, and activating immune cells in the tumor microenvironment or recruiting immune cells to the tumor for breaking out the immunosuppression by glioma cells.

CONCLUSION

The application of peptides has revolutionized the treatment of glioma, which is based on targeting, penetrating, anti-tumor activities, and immunostimulatory. Moreover, better outcomes have been discovered in combining different kinds of peptides rather than a single one. Until now, more and more preclinical studies have been developed with multifarious peptides, which show promising results in vitro or vivo with the model of glioma.

Fenton-magnetic based therapy by dual-chemodrug-loaded magnetic hydroxyapatite against colon cancer

Fenton-based therapy is emerging as an effective and selective strategy against cancer. However, a low concentration of transition metal ions, insufficient endogenous H₂O_2, and a high level of antioxidant activity within the cancer cells have hindered the therapeutic efficacy of this strategy. To address these issues, in this study, the Fenton reagent (magnetic hydroxyapatite, mHAP) was accompanied with chemotherapy drugs (cisplatin (CDDP) and methotrexate (MTX)) and static magnetic field (SMF), in such a way to be a pH-, redox-, and magnetic-responsive nanoplatform. In vitro and in vivo experiments revealed higher toxicity of the final construct, MTX.CDDP@mHAP, toward colon cancer cells, as compared with that of free drugs. The most effective antitumor activity was observed as MTX.CDDP@mHAP-treated tumor cells were exposed to SMF (0.9 T) and no noticeable damage was observed in the normal cells and tissues. Active targeting by MTX and magnetic targeting by mHAP under magnetic field increased the tumor selectivity and enhanced the tumor site accumulation and cellular uptake of MTX.CDDP@mHAPs. The released iron ions within the cancer cells trigger the Fenton reaction while the release of chemotherapy drugs, reduction of intracellular glutathione, and application of SMF aggravated the Fenton reaction, subsequently leading to the generation of reactive oxygen species (ROS) and induction of apoptosis. Therefore, Fenton magnetic-based therapy-mediated by MTX.CDDP@mHAP could be considered as a promising strategy against colon cancer with high therapeutic efficiency and biosafety.

Improving the Cellular Uptake of Biomimetic Magnetic Nanoparticles

Magnetococcus marinus magnetosome-associated protein MamC, expressed as recombinant, has been proven to mediate the formation of novel biomimetic magnetic nanoparticles (BMNPs) that are successful drug nanocarriers for targeted chemotherapy and hyperthermia agents. These BMNPs present several advantages over inorganic magnetic nanoparticles, such as larger sizes that allow the former to have larger magnetic moment per particle, and an isoelectric point at acidic pH values, which allows both the stable functionalization of BMNPs at physiological pH value and the molecule release at acidic (tumor) environments, simply based on electrostatic interactions. However, difficulties for BMNPs cell internalization still hold back the efficiency of these nanoparticles as drug nanocarriers and hyperthermia agents. In the present study we explore the enhanced BMNPs internalization following upon their encapsulation by poly (lactic-co-glycolic) acid (PLGA), a Food and Drug Administration (FDA) approved molecule. Internalization is further optimized by the functionalization of the nanoformulation with the cell-penetrating TAT peptide (TATp). Our results evidence that cells treated with the nanoformulation [TAT-PLGA(BMNPs)] show up to 80% more iron internalized (after 72 h) compared to that of cells treated with BMNPs (40%), without any significant decrease in cell viability. This nanoformulation showing optimal internalization is further characterized. In particular, the present manuscript demonstrates that neither its magnetic properties nor its performance as a hyperthermia agent are significantly altered due to the encapsulation. In vitro experiments demonstrate that, following upon the application of an alternating magnetic field on U87MG cells treated with BMNPs and TAT-PLGA(BMNPs), the cytotoxic effect of BMNPs was not affected by the TAT-PLGA enveloping. Based on that, difficulties shown in previous studies related to poor cell uptake of BMNPs can be overcome by the novel nanoassembly described here.