Selective targeting by preS1 domain of hepatitis B surface antigen conjugated with phosphorylcholine-based amphiphilic block copolymer micelles as a biocompatible, drug delivery carrier for treatment of human hepatocellular carcinoma with paclitaxel

Recent advances of novel targeted drug delivery systems based on natural medicine monomers against hepatocellular carcinoma

Hepatocellular carcinoma (HCC), the most prevalent type of liver cancer, is often diagnosed at an advanced stage. Surgical interventions are often ineffective, leading HCC patients to rely on systemic chemotherapy. Unfortunately, commonly used chemotherapeutic drugs have limited efficacy and can adversely affect vital organs, causing significant physical and psychological distress for patients. Natural medicine monomers (NMMs) have shown promising efficacy and safety profiles in HCC treatment, garnering attention from researchers. In recent years, the development of novel targeted drug delivery systems (TDDS) combining NMMs with nanocarriers has emerged. These TDDS aim to concentrate drugs effectively in HCC cells by manipulating the characteristics of nanomedicines, leveraging receptor and ligand interactions, and utilizing endogenous stimulatory responses to promote specific nanomedicines distribution. This comprehensive review presents recent research on TDDS for HCC treatment using NMMs from three perspectives: passive TDDS, active TDDS, and stimuli-responsive drug delivery systems (SDDS). It consolidates the current state of research on TDDS for HCC treatment with NMMs and highlights the potential of these innovative approaches in improving treatment outcomes. Moreover, the review also identifies research gaps in the related fields to provide references for future targeted therapy research in HCC.

Modeling Polyzwitterion-Based Drug Delivery Platforms: A Perspective of the Current State-of-the-Art and Beyond

Drug delivery platforms are anticipated to have biocompatible and bioinert surfaces. PEGylation of drug carriers is the most approved method since it improves water solubility and colloid stability and decreases the drug vehicles' interactions with blood components. Although this approach extends their biocompatibility, biorecognition mechanisms prevent them from biodistribution and thus efficient drug transfer. Recent studies have shown (poly)zwitterions to be alternatives for PEG with superior biocompatibility. (Poly)zwitterions are super hydrophilic, mainly stimuli-responsive, easy to functionalize and they display an extremely low protein adsorption and long biodistribution time. These unique characteristics make them already promising candidates as drug delivery carriers. Furthermore, since they have highly dense charged groups with opposite signs, (poly)zwitterions are intensely hydrated under physiological conditions. This exceptional hydration potential makes them ideal for the design of therapeutic vehicles with antifouling capability, i.e., preventing undesired sorption of biologics from the human body in the drug delivery vehicle. Therefore, (poly)zwitterionic materials have been broadly applied in stimuli-responsive "intelligent" drug delivery systems as well as tumor-targeting carriers because of their excellent biocompatibility, low cytotoxicity, insignificant immunogenicity, high stability, and long circulation time. To tailor (poly)zwitterionic drug vehicles, an interpretation of the structural and stimuli-responsive behavior of this type of polymer is essential. To this end, a direct study of molecular-level interactions, orientations, configurations, and physicochemical properties of (poly)zwitterions is required, which can be achieved via molecular modeling, which has become an influential tool for discovering new materials and understanding diverse material phenomena. As the essential bridge between science and engineering, molecular simulations enable the fundamental understanding of the encapsulation and release behavior of intelligent drug-loaded (poly)zwitterion nanoparticles and can help us to systematically design their next generations. When combined with experiments, modeling can make quantitative predictions. This perspective article aims to illustrate key recent developments in (poly)zwitterion-based drug delivery systems. We summarize how to use predictive multiscale molecular modeling techniques to successfully boost the development of intelligent multifunctional (poly)zwitterions-based systems.

Emerging Phospholipid Nanobiomaterials for Biomedical Applications to Lab-on-a-Chip, Drug Delivery, and Cellular Engineering

The design of advanced nanobiomaterials to improve analytical accuracy and therapeutic efficacy has become an important prerequisite for the development of innovative nanomedicines. Recently, phospholipid nanobiomaterials including 2-methacryloyloxyethyl phosphorylcholine (MPC) have attracted great attention with remarkable characteristics such as resistance to nonspecific protein adsorption and cell adhesion for various biomedical applications. Despite many recent reports, there is a lack of comprehensive review on the phospholipid nanobiomaterials from synthesis to diagnostic and therapeutic applications. Here, we review the synthesis and characterization of phospholipid nanobiomaterials focusing on MPC polymers and highlight their attractive potentials for applications in micro/nanofabricated fluidic devices, biosensors, lab-on-a-chip, drug delivery systems (DDSs), COVID-19 potential usages for early diagnosis and even treatment, and artificial extracellular matrix scaffolds for cellular engineering.

Zwitterionic polymers in drug delivery: A review

Developments of novel drug delivery vehicles are sought-after to augment the therapeutic effectiveness of standard drugs. An urgency to design novel drug delivery vehicles that are sustainable, biocompatible, have minimized cytotoxicity, no immunogenicity, high stability, long circulation time, and are capable of averting recognition by the immune system is perceived. In this pursuit for an ideal candidate for drug delivery vehicles, zwitterionic materials have come up as fulfilling almost all these expectations. This comprehensive review is presenting the progress made by zwitterionic polymeric architectures as prospective sustainable drug delivery vehicles. Zwitterionic polymers with varied architecture such as appending protein conjugates, nanoparticles, surface coatings, liposomes, hydrogels, etc, used to fabricate drug delivery vehicles are reviewed here. A brief introduction of zwitterionic polymers and their application as reliable drug delivery vehicles, such as zwitterionic polymer-protein conjugates, zwitterionic polymer-based drug nanocarriers, and stimulus-responsive zwitterionic polymers are discussed in this discourse. The prospects shown by zwitterionic architecture suggest the tremendous potential for them in this domain. This critical review will encourage the researchers working in this area and boost the development and commercialization of such devices to benefit the healthcare fraternity.

Developing Anisotropy in Self-Assembled Block Copolymers: Methods, Properties, and Applications

Block copolymers (BCPs) self-assembly has continually attracted interest as a means to provide bottom-up control over nanostructures. While various methods have been demonstrated for efficiently ordering BCP nanodomains, most of them do not generically afford control of nanostructural orientation. For many applications of BCPs, such as energy storage, microelectronics, and separation membranes, alignment of nanodomains is a key requirement for enabling their practical use or enhancing materials performance. This review focuses on summarizing research progress on the development of anisotropy in BCP systems, covering a variety of topics from established aligning techniques, resultant material properties, and the associated applications. Specifically, the significance of aligning nanostructures and the anisotropic properties of BCPs is discussed and highlighted by demonstrating a few promising applications. Finally, the challenges and outlook are presented to further implement aligned BCPs into practical nanotechnological applications, where exciting opportunities exist.

Bone-targeting phospholipid polymers to solubilize the lipophilic anticancer drug

Current chemotherapy methods have limited effectiveness in eliminating bone metastasis, which leads to a poor prognosis associated with severe bone disorders. To provide regional chemotherapy for this metastatic tumor, a bone-targeting drug carrier was produced by introducing the osteotropic bisphosphonate alendronate (ALN) units into an amphiphilic phospholipid polymer, poly(2-methacryloyloxyethyl phosphorylcholine-co-n-butyl methacrylate). The polymer can form nanoparticles with a diameter of less than 30 nm; ALN units were exposed to the outer layer of the particle. A simple mixing procedure was used to encapsulate a hydrophobic anticancer drug, known as docetaxel (DTX), in the polymer nanoparticle, providing a uniform solution of a polymer-DTX complex in the aqueous phase. The complex showed anticancer activities against several breast cancer cell lines, and the complex formation did not hamper the pharmacological effect of DTX. The fluorescence observations evaluated by an in vivo imaging system and fluorescence microscopy showed that the addition of ALN to the polymer-DTX complex enhanced bone accumulation. Bone-targeting phospholipid polymers are potential solubilizing excipients used to formulate DTX and deliver the hydrophobic drug to bone tissues by blood administration.

Synthesis and Characterization of PMBN as A Biocompatible Nanopolymer for Bio-Applications

Objective

Poly [2-methacryloyloxyethyl phosphoryl choline (MPC)-co-n-buthyl methacrylate (BMA)-co-p-nitrophenyl-oxycrabonyl poly ethylene glycol-methacrylate (ME- ONP)] (PMBN), a biocompatible terpolymer, is a unique polymer with applications that range from drug delivery systems (DDS) to scaffolds and biomedical devices. In this research, we have prepared a monomer of p-nitrophenyl-oxycarbonyl poly (ethylene glycol) methacrylate (MEONP) to synthesize this polymer. Next, we designed and prepared a smart, water soluble, amphiphilic PMBN polymer composed of MPC, BMA, and MEONP.

Materials and Methods

In this experimental study, we dissolved MPC (4 mmol, 40% mole fraction), BMA (5 mmol, 50% mole fraction), and MEONP (1 mmol, 10% mole fraction) in 20 ml of dry ethanol in two necked flasks equipped with inlet-outlet gas. The structural characteristics of the synthesized monomer and polymer were determined by Fourier transform infrared spectroscopy (FT-IR), proton nuclear magnetic resonance (H-NMR), dynamic light scattering (DLS), gel permeation chromatography (GPC), scanning electron microscope (SEM), and transmission electron microscope (TEM) analyses for the first time. We treated the polymer with two different cell lines to determine its biocompatibility.

Results

FT-IR and H-NMR analyses confirmed the synthesis of the polymer. The size of polymer was approximately 40 nm with a molecular weight (MW) of 52 kDa, which would be excellent for a nano carrier. Microscopic analyses showed that the polymer was rodshaped. This polymer had no toxicity for individual cells.

Conclusion

We report here, for the first time, the full properties of the PMBN polymer. The approximately 40 nm size with an acceptable zeta potential range of -8.47, PDI of 0.1, and rod-shaped structure indicated adequate parameters of a nanopolymer for nano bioapplications. We used this polymer to design a new smart nano carrier to treat leukemia stem cells based on a target DDS as a type of bio-application.

Effects of copolymer component on the properties of phosphorylcholine micelles

Zwitterionic polymers have unique features, such as good compatibility, and show promise in the application of drug delivery. In this study, the zwitterionic copolymers, poly(ε-caprolactone)-b-poly(2-methacryloyloxyethyl phosphorylcholine) with disulfide (PCL-ss-PMPC) or poly(ε-caprolactone)-b-poly(2-methacryloyloxyethyl phosphorylcholine) or without disulfide (PCL-PMPC) and with different block lengths in PCL-ss-PMPC, were designed. The designed copolymers were obtained by a combination of ring-opening polymerization and atom transferring radical polymerization. The crystallization properties of these polymers were investigated. The micelles were prepared based on the obtained copolymers with zwitterionic phosphorylcholine as the hydrophilic shell and PCL as the hydrophobic core. The size distributions of the blank micelles and the doxorubicin (DOX)-loaded micelles were uniform, and the micelle diameters were <100 nm. In vitro drug release and intracellular drug release results showed that DOX-loaded PCL-ss-PMPC micelles could release drugs faster responding to the reduction condition and the intracellular microenvironment in contrast to PCL-PMPC micelles. Moreover, in vitro cytotoxicity evaluation revealed that the designed copolymers possessed low cell toxicity, and the inhibiting effect of DOX-loaded phosphorylcholine micelles to tumor cells was related to the components of these copolymers. These results reveal that the reduction-responsive phosphorylcholine micelles with a suitable ratio of hydrophilic/hydrophobic units can serve as promising drug carriers.

Dendritic polyglycerol sulfate as a novel platform for paclitaxel delivery: pitfalls of ester linkage

In this study, dendritic polyglycerol sulfate (dPGS) is evaluated as a delivery platform for the anticancer, tubulin-binding drug paclitaxel (PTX). The conjugation of PTX to dPGS is conducted via a labile ester linkage. A non-sulfated dendritic polyglycerol (dPG) is used as a control, and the labeling with an indocarbocyanine dye (ICC) renders multifunctional conjugates that can be monitored by fluorescence microscopy. The conjugates are characterized by (1)H NMR, UV-vis measurements, and RP-HPLC. In vitro cytotoxicity of PTX and dendritic conjugates is evaluated using A549 and A431 cell lines, showing a reduced cytotoxic efficacy of the conjugates compared to PTX. The study of uptake kinetics reveals a linear, non saturable uptake in tumor cells for dPGS-PTX-ICC, while dPG-PTX-ICC is hardly taken up. Despite the marginal uptake of dPG-PTX-ICC, it prompts tubulin polymerization to a comparable extent as PTX. These observations suggest a fast ester hydrolysis and premature drug release, as confirmed by HPLC measurements in the presence of plasma enzymes.

Diagnostic imaging and therapeutic application of nanoparticles targeting the liver

Liver diseases, particularly viral hepatitis, cirrhosis and hepatocellular carcinoma, are common in clinical practice with high morbidity and mortality worldwide. Many substances for diagnostic imaging and therapy of liver diseases may have either severe adverse effects or insufficient effectiveness in vivo because of their nonspecific uptake. Therefore, by targeting the delivery of drugs into the liver or specific liver cells, drug efficiency may be largely improved. This review summarizes the up-to-date research progress focusing on nanoparticles targeting the liver for both diagnostic and therapeutic purposes. Targeting strategies, mechanisms of enhanced effects, and clinical applications of nanoparticles are discussed specifically. We believe that new targeting nanotechnology such as nanoprobes for multi-modality imaging and multifunctional nanoparticles would facilitate significant advancements in this active research area in the near future.

Liver cell-specific peptides derived from the preS1 domain of human hepatitis B virus

The envelope of human hepatitis B virus (HBV) consists of the large (L), middle (M), and small (S) surface proteins. The preS1 domain at the N terminus of the L-protein is essential for recognizing a target cell and for viral infectivity. In the present study, peptides derived from the preS1 domain (amino acid residues 2-19) were synthesized, and their binding affinities for human hepatocellular carcinoma (HCC) cells were determined. Non-myristoylated peptides showed much lower affinity for HepG2 cells than myristoylated peptides. Although all peptides showed significantly higher affinities for two human HCC cell lines (HepG2 and HuH-7) compared with other cell lines (HeLa, B16, NMuLi, and NIH 3T3), a modified peptide exhibited the highest affinity for HCC cell lines. These results suggest that the modified peptide can target liver cells.

Photodynamic therapy using an anti-EGF receptor antibody complexed with verteporfin nanoparticles: a proof of concept study

Photodynamic therapy (PDT) is a noninvasive optical treatment method in which the topical or systemic delivery of photosensitizing drugs is followed by irradiation with broadband red light. Coupling photosensitizers with a specific antibody may allow this approach to target specific cancers. This study determines the antitumor efficacy of coupling verteporfin (Visudyne(®)), a hydrophobic polyporphryin oligomer, with an antiepidermal growth factor receptor (anti-EGFR) antibody. Poly[2-methacryloyloxyethyl phosphorylcholine-co-n-butyl methacrylate-co-p-nitrophenylcarbonyloxyethyl methacrylate] (PMBN) was conjugated with an anti-EGFR antibody and mixed with verteporfin (verteporfin-PMBN-antibody complex). Tumor-bearing mice were intravenously injected with the verteporfin-PMBN-antibody complex or verteporfin plus PMBN without the antibody. Irradiation was conducted at 640 nm with a dose of 75 J/cm(2). The fluorescence intensity in A431 cells in vitro was threefold higher after exposure to verteporfin-PMBN-antibody complex than after exposure to verteporfin-PMBN. In A431 tumor-bearing mice, the intratumor concentration of verteporfin was 9.4 times higher than that of the skin, following administration of the verteporfin-PMBN-antibody complex. Tumor size significantly decreased within 8 days in mice treated with verteporfin-PMBN-antibody complex compared with those treated with verteporfin-PMBN. PDT using a PMBN-verteporfin-antibody complex offers a promising anticancer therapy.

An insight into the metabolic responses of ultra-small superparamagnetic particles of iron oxide using metabonomic analysis of biofluids

Ultra-small superparamagnetic particles of iron oxides (USPIO) have been developed as intravenous organ/tissue-targeted contrast agents to improve magnetic resonance imaging (MRI) in vivo. However, their potential toxicity and effects on metabolism have attracted particular attention. In the present study, uncoated and dextran-coated USPIO were investigated by analyzing both rat urine and plasma metabonomes using high-resolution NMR-based metabonomic analysis in combination with multivariate statistical analysis. The wealth of information gathered on the metabolic profiles from rat urine and plasma has revealed subtle metabolic changes in response to USPIO administration. The metabolic changes include the elevation of urinary alpha-hydroxy-n-valerate, o- and p-HPA, PAG, nicotinate and hippurate accompanied by decreases in the levels of urinary alpha-ketoglutarate, succinate, citrate, N-methylnicotinamide, NAG, DMA, allantoin and acetate following USPIO administration. The changes associated with USPIO administration included a gradual increase in plasma glucose, N-acetyl glycoprotein, saturated fatty acid, citrate, succinate, acetate, GPC, ketone bodies (beta-hydroxybutyrate, acetone and acetoacetate) and individual amino acids, such as phenylalanine, lysine, isoleucine, glycine, glutamine and glutamate and a gradual decrease of myo-inositol, unsaturated fatty acid and triacylglycerol. Hence USPIO administration effects are reflected in changes in a number of metabolic pathways including energy, lipid, glucose and amino acid metabolism. The size- and surface chemistry-dependent metabolic responses and possible toxicity were observed using NMR analysis of biofluids. These changes may be attributed to the disturbances of hepatic, renal and cardiac functions following USPIO administrations. The potential biotoxicity can be derived from metabonomic analysis and serum biochemistry analysis. Metabonomic strategy offers a promising approach for the detection of subtle physiological responses on mammalian metabolism, and can be employed to investigate the potential adverse effects of other nanoparticles and nanomaterials on the environment and human health.