Lipid polymer hybrid nanoparticles: a custom-tailored next-generation approach for cancer therapeutics

Lipid-based polymeric nanoparticles are the highly popular carrier systems for cancer drug therapy. But presently, detailed investigations have revealed their flaws as drug delivery carriers. Lipid polymer hybrid nanoparticles (LPHNPs) are advanced core-shell nanoconstructs with a polymeric core region enclosed by a lipidic layer, presumed to be derived from both liposomes and polymeric nanounits. This unique concept is of utmost importance as a combinable drug delivery platform in oncology due to its dual structured character. To add advantage and restrict one's limitation by other, LPHNPs have been designed so to gain number of advantages such as stability, high loading of cargo, increased biocompatibility, rate-limiting controlled release, and elevated drug half-lives as well as therapeutic effectiveness while minimizing their drawbacks. The outer shell, in particular, can be functionalized in a variety of ways with stimuli-responsive moieties and ligands to provide intelligent holding and for active targeting of antineoplastic medicines, transport of genes, and theragnostic. This review comprehensively provides insight into recent substantial advancements in developing strategies for treating various cancer using LPHNPs. The bioactivity assessment factors have also been highlighted with a discussion of LPHNPs future clinical prospects.

Advanced cancer targeting using aptamer functionalized nanocarriers for site-specific cargo delivery

The non-specificity of standard anticancer therapies has profound detrimental consequences in clinical treatment. Therapeutic specificity can be precisely achieved using cutting-edge ligands. Small synthetic oligonucleotide-ligands chosen through Systematic evolution of ligands by exponential enrichment (SELEX) would be an unceasing innovation in using nucleic acids as aptamers, frequently referred to as "chemical antibodies." Aptamers act as externally controlled switching materials that can attach to various substrates, for example, membrane proteins or nucleic acid structures. Aptamers pose excellent specificity and affinity for target molecules and can be used as medicines to suppress tumor cell growth directly. The creation of aptamer-conjugated nanoconstructs has recently opened up innovative options in cancer therapy that are more effective and target tumor cells with minor toxicity to healthy tissues. This review focuses on a comprehensive description of the most capable classes of aptamer-tethered nanocarriers for precise recognition of cancer cells with significant development in proficiency, selectivity, and targetability for cancer therapy. Existing theranostic applications with the problems and future directions are also highlighted.

GLUT1 transporter-facilitated solid lipid nanoparticles loaded with anti-cancer therapeutics for ovarian cancer targeting

The therapeutics available for cancer treatment have the major hurdle of site-specific delivery of anti-cancer drugs to the tumor site and non-target specific side effects. The standard therapy for ovarian cancer still poses numerous pitfalls due to the irrational use of drugs affecting healthy cells. As an appealing approach, nanomedicine could revamp the therapeutic profile of anti-cancer agents. Owing to the low manufacturing cost, increased biocompatibility, and modifiable surface properties, lipid-based nanocarriers, particularly solid lipid nanoparticles (SLN), have remarkable drug delivery properties in cancer treatment. Given the extra-ordinary benefits, we developed anti-neoplastic (paclitaxel) drug-loaded SLN (PTX-SLN) and functionalized with N-acetyl-d-glucosamine (GLcNAc) (GLcNAc-PTX-SLN) to reduce the rate of proliferation, growth, and metastasis of ovarian cancer cells over-expressing GLUT1 transporters. The particles presented considerable size and distribution while demonstrating haemocompatibility. Using GLcNAc modified form of SLNs, confocal microscopy, MTT assay, and flow cytometry study demonstrated higher cellular uptake and significant cytotoxic effect. Also, molecular docking results established excellent binding affinity between GLcNAc and GLUT1, complimenting the feasibility of the therapeutic approach in targeted cancer therapy. Following the compendium of target-specific drug delivery by SLN, our results demonstrated a significant response for ovarian cancer therapy.

An In Vivo Investigation of Ascorbic Acid Tethered Polymeric Nanoparticles for Effectual Brain Transport of Rivastigmine

INTRODUCTION

The goal of this study was to see if ascorbic acid grafted polylactic glycolic acid-b-polyethylene glycol nanoparticles (PLGA-b-PEG NPs) might boost the carrying or transport capacity of rivastigmine (RSM) to the brain via choroid plexus Sodium-dependent vitamin C transporter 2 (SVCT2 transporters). The IR and 1H NMR, were used to characterise the PLGA-b-PEG copolymer.

METHODS

Nanoprecipitation method was used to make PLGA-b-PEG NPs. To promote SVCT2-mediated transportation of ascorbic acid (Asc) into the brain, PLGA-b-PEG NPs of acceptable size, polydispersity, and drug loading were bound with ascorbic acid (PLGA-b-PEG-Asc). When compared to PLGA-b-mPEG NPs, the surface functionalization of NPs with ascorbic acid dramatically improved cellular uptake of NPs in SVCT2 expressing NIH/3T3 cells. Radial Arm Maze Test, and Acetylcholinesterase (AChE) activity in scopolamine-induced amnetic rats were used to assess in vivo pharmacodynamic effectiveness.

RESULT

In vivo pharmacodynamic tests revealed that drug loaded PLGA-b-PEG-Asc NPs had much greater therapeutic and sustained activity than free drugs, and PLGA-b-mPEG NPs to the brain.

CONCLUSION

As a consequence, the findings revealed that using ascorbic acid grafted PLGA-b-PEG NPs to deliver bioactives to the brain is a potential strategy.

Efficient in vitro and in vivo docetaxel delivery mediated by pH-sensitive LPHNPs for effective breast cancer therapy

The present study was designed to develop pH-sensitive lipid polymer hybrid nanoparticles (pHS-LPHNPs) for specific cytosolic-delivery of docetaxel (DTX). The pHS-LPHNPs-DTX formulation was prepared by self-assembled nano-precipitation technique and characterized for zeta potential, particle size, entrapment efficiency, polydispersity index (PDI), and in vitro drug release. In vitro cytotoxicity of pHS-LPHNPs-DTX was assessed on breast cancer cells (MDA-MB-231 and MCF-7) and compared with DTX-loaded conventional LPHNPs and bare DTX. In vitro cellular uptake in MDA-MB-231 cell lines showed better uptake of pHS-LPHNPs. Further, a significant reduction in the IC₅₀ of pHS-LPHNPs-DTX against both breast cancer cells was observed. Flow cytometry results showed greater apoptosis in case of pHS-LPHNPs-DTX treated MDA-MB-231 cells. Breast cancer was experimentally induced in BALB/c female mice, and the in vivo efficacy of the developed pHS-LPHNPs formulation was assessed with respect to the pharmacokinetics, biodistribution in the vital organs (liver, kidney, heart, lungs, and spleen), percentage tumor burden, and survival of breast cancer-bearing animals. In vivo studies showed improved pharmacokinetic and target-specificity with minimum DTX circulation in the deep-seated organs in the case of pHS-LPHNPs-DTX compared to the LPHNPs-DTX and free DTX. Mice treated with pHS-LPHNPs-DTX exhibited a significantly lesser tumor burden than other treatment groups. Also, reduced distribution of DTX in the serum was evident for pHS-LPHNPs-DTX treated mice compared to the LPHNPs-DTX and free DTX. In essence, pHS-LPHNPs mediated delivery of DTX presents a viable platform for developing therapeutic-interventions against breast-cancer.

Dequalinium-derived nanoconstructs: A promising vehicle for mitochondrial targeting

The power house of the cell; mitochondrion, is a vital organelle for drug targeting in the treatment of many diseases owing to its fundamental duties and function related to cell proliferation and death. The mitochondrial membrane comprises bilayer artifact and pose extremely negative potential which create hurdle for therapeutic molecules in reaching mitochondria. To accomplish mitochondrial targeting, the scientific community has explored diverse pharmaceutical formulations like liposomes, polymeric nanoparticles (NPs), and inorganic NPs. However, the game changing technology was modification of these carriers by mitochondriotropic moiety, dequalinium chloride (DQA) or delivering the chemotherapeutics by DQAsomes. The DQA represents a distinctive mitochondriotropic delocalized cation that display their selectivity towards accumulation in mitochondria of carcinoma cell. Attributed to this characteristics, DQAsomes have been formulated using DQA and explored for successful mitochondrial targeting of bioactives. In this review, we have discussed the effectiveness of DQA nanocarriers which efficiently and selectively transmit the cytotoxic drug to the tumor cell. The DQA based nanoformulations have evidently displayed augmented pharmacological and therapeutic outcome than their counterparts both in vitro and in vivo. Thus, DQAsomes symbolizes an ideal carrier with excellent potential as mitochondial targeting agent.

Biodegradable dendritic Boltorn™ nanoconstructs: A promising avenue for cancer theranostics

The family of Boltorn™ H40 dendrimers is an imperative subclass of hyperbranched biodegradable polymers (HBPs), which has received mounting attention as a result of its inimitable chemical, physical and biodegradable properties. These properties embrace three-dimensional dendrimeric nanoarchitecture to avert tanglement between polymer branches, adequate spatial cavities for increased encapsulation of guest molecules, good solubility as well as low viscosity to improve processability, and a huge number of surface functional groups for chemical manipulations. Similarly, low toxicity, non-immunogenicity, and natural biodegradation are significant and critical advantages in therapeutic applications as compared to other dendritic polymers. All these characteristics of Boltorn™ H40 are of pronounced importance for planning and developing advanced targeted cargo delivery carriers for cancer therapy. The present review highlights the applications of Boltorn™ H40 HBPs for the transport of chemotherapeutic agents to manage various types of cancers.

PEGylated nanocarriers: A promising tool for targeted delivery to the brain

Targeted drug delivery across the blood-brain barrier is an extremely challenging quest in the fight with fatal brain ailments, with the major hurdles being short circulation time, reticuloendothelial system (RES) uptake, and excretion of nanocarriers. PEGylation has emerged as a boon for targeted drug delivery to the brain. It is well established that PEGylation can increase the circulation time of nanocarriers by avoiding RES uptake, which is indispensable for increasing the brain's uptake of nanocarriers. PEGylation also acts as a linker for ligand molecules to achieve active targeting to the brain. Using PEGylation, novel approaches are being investigated to facilitate ligand-receptor interactions at the brain endothelium to ease the entry of therapeutic drugs into the brain. In addition, PEGylation made it simpler to assess the brain tissue for delivering diagnostic molecules and theranostic nanocarriers. The potential of PEGylated nanocarriers is being investigated vastly to boost the therapeutic effect several fold in the treatment of brain diseases. This review sheds light on the contribution of PEGylated nanocarriers, especially liposomes, polymeric nanoparticles, and dendrimers for brain-specific delivery of bioactives.

cRGD functionalised nanocarriers for targeted delivery of bioactives

The integrins α_vβ₃ play a very imperative role in angiogenesis and are overexpressed in endothelial cells of the tumour. Recent years have witnessed huge exploration in the field of α_vβ₃ integrin-mediated bioactive targeting for treatment of cancer. In these studies, the cRGD peptide has been employed extensively owing to their binding capacity to the α_vβ₃ integrin. Principally, RGD-based approaches comprise of antagonist molecules of the RGD sequence, drug-RGD conjugates, and most importantly tethering of the nanocarrier surface with the RGD peptide as targeting ligand. Targeting tumour vasculature or cells via cRGD conjugated nanocarriers have emerged as a promising technique for delivering chemotherapeutic drugs and imaging agents for cancer theranostics. In this review, primary emphasis has been given on the application of cRGD-anchored nanocarriers for targeted delivery of drugs, imaging agents, etc. for tumour therapy.

Enhanced oral bioavailability of griseofulvin via niosomes

The aim of the present report was to develop nonionic surfactant vesicles (niosomes) to improve poor and variable oral bioavailability of griseofulvin. Niosomes were prepared by using different nonionic surfactants span 20, span 40, and span 60. The lipid mixture consisted of surfactant, cholesterol, and dicetyl phosphate in the molar ratio of 125:25:1.5, 100:50:1.5, and 75:75:1.5, respectively. The niosomal formulations were prepared by thin film method and ether injection method. The influence of different formulation variables such as surfactant type, surfactant concentration, and cholesterol concentration was optimized for size distribution and entrapment efficiency for both methods. Result indicated that the niosomes prepared by thin film method with span 60 provided higher entrapment efficiency. The niosomal formulation exhibited significantly retarded in vitro release as compared with free drug. The in vivo study revealed that the niosomal dispersion significantly improved the oral bioavailability of griseofulvin in albino rats after a single oral dose. The maximum concentration (Cmax) achieved in case of niosomal formulation was approximately double (2.98 microg/ml) as compared to free drug (1.54 microg/ml). Plasma drug profile also suggested that the developed niosomal system also has the potential of maintaining therapeutic level of griseofulvin for a longer period of time as compared to free griseofulvin. The niosomal formulation showed significant increase in area under the curve0-24 (AUC; 41.56 microg/ml h) as compared to free griseofulvin (22.36 microg/ml h) reflecting sustained release characteristics. In conclusion, the niosomal formulation could be one of the promising delivery system for griseofulvin with improved oral bioavailability and prolonged drug release profiles.