Functionalized Tobacco Mosaic Virus Coat Protein Monomers and Oligomers as Nanocarriers for Anti-Cancer Peptides

Assessment of a Structurally Modified Alternanthera Mosaic Plant Virus as a Delivery System for Sarcoma Cells

The virions of plant viruses and their structurally modified particles (SP) represent valuable platforms for recombinant vaccine epitopes and antitumor agents. The possibility of modifying their surface with biological compounds makes them a tool for developing medical biotechnology applications. Here, we applied a new type of SP derived from virions and virus-like particles (VLP) of Alternanthera mosaic virus (AltMV) and well-studied SP from Tobacco mosaic virus (TMV). We have tested the ability of SP from AltMV (AltMV SPV) and TMV virions also as AltMV VLP to bind to and penetrate Ewing sarcoma cells. The adsorption properties of AltMV SPV and TMV SP are greater than those of the SP from AltMV VLP. Compared to normal cells, AltMV SPV adsorbed more effectively on patient-derived sarcoma cells, whereas TMV SP were more effective on the established sarcoma cells. The AltMV SPV and TMV SP were captured by all sarcoma cell lines. In the established Ewing sarcoma cell line, the effectiveness of AltMV SPV penetration was greater than that of TMV SP. The usage of structurally modified plant virus particles as a platform for drugs and delivery systems has significant potential in the development of anticancer agents.

Advances in tumor vascular growth inhibition

Tumor growth and metastasis require neovascularization, which is dependent on a complex array of factors, such as the production of various pro-angiogenic factors by tumor cells, intercellular signaling, and stromal remodeling. The hypoxic, acidic tumor microenvironment is not only conducive to tumor cell proliferation, but also disrupts the equilibrium of angiogenic factors, leading to vascular heterogeneity, which further promotes tumor development and metastasis. Anti-angiogenic strategies to inhibit tumor angiogenesis has, therefore, become an important focus for anti-tumor therapy. The traditional approach involves the use of anti-angiogenic drugs to inhibit tumor neovascularization by targeting upstream and downstream angiogenesis-related pathways or pro-angiogenic factors, thereby inhibiting tumor growth and metastasis. This review explores the mechanisms involved in tumor angiogenesis and summarizes currently used anti-angiogenic drugs, including monoclonal antibody, and small-molecule inhibitors, as well as the progress and challenges associated with their use in anti-tumor therapy. It also outlines the opportunities and challenges of treating tumors using more advanced anti-angiogenic strategies, such as immunotherapy and nanomaterials.

Nanoparticle-mediated therapeutic management in cholangiocarcinoma drug targeting: Current progress and future prospects

Patients with cholangiocarcinoma (CCA) often have an unfavorable prognosis because of its insidious nature, low resectability rate, and poor response to anticancer drugs and radiotherapy, which makes early detection and treatment difficult. At present, CCA has a five-year overall survival rate (OS) of only 5%, despite advances in therapies. New an increasing number of evidence suggests that nanoplatforms may play a crucial role in enhancing the pharmacological effects and in reducing both short- and long-term side effects of cancer treatment. This document reviews the advantages and shortcomings of nanoparticles such as liposomes, polymeric nanoparticle，inorganic nanoparticle, nano-metals and nano-alloys, carbon dots, nano-micelles, dendrimer, nano-capsule, bio-Nanomaterials in the diagnosis and treatment of CCA and discuss the current challenges in of nanoplatforms for CCA.

Transmembrane peptide effects on bacterial membrane integrity and organization

As the bacterial multidrug resistance crisis continues, membrane-active antimicrobial peptides are being explored as an alternate treatment to conventional antibiotics. In contrast to antimicrobial peptides, which function by a nonspecific membrane disruption mechanism, here we describe a series of transmembrane (TM) peptides that are designed to act as drug efflux inhibitors by aligning with and out-competing a conserved TM4-TM4 homodimerization motif within bacterial small multidrug resistance proteins. The peptides contain two terminal tags: a C-terminal lysine tag to direct the peptides toward the negatively charged bacterial membrane, and an uncharged N-terminal sarcosine (N-methyl-glycine) tag to promote membrane insertion. While effective at inhibiting efflux activity, ostensibly through their designed mechanism of action, the impact of the peptides on the bacterial inner membrane remains undetermined. To evaluate the extant peptide-membrane interactions, we performed a series of biophysical measurements. Circular dichroism spectroscopy and Trp fluorescence showed that the peptides insert into the membrane generally in helical form. Interestingly, differential scanning calorimetry of the peptides added to bacterial-like membranes (POPE:POPG 3:1) revealed the peptides' ability to demix the POPE and POPG lipids, creating two pools, one of which is likely a peptide-POPG conglomerate, and the other a POPE-rich component where the native POPG content has been depleted. However, dye leakage assays confirmed that these events occur without causing significant membrane disruption both in vitro and in vivo, indicating that the peptides can target the small multidrug resistance TM4-TM4 motif without nonspecific membrane disruption. In related studies, DiOC2(3) fluorescence indicated moderate peptide-mediated reduction of the proton motive force for all peptides, including control peptides that did not display inhibitory activity. The overall findings suggest that peptides designed with suitable tags, sequence hydrophobicity, and charge distribution can be directed more generally to impact proteins whose function involves membrane-embedded protein-protein interactions.

Multifunctional Plant Virus Nanoparticles for Targeting Breast Cancer Tumors

Breast cancer treatment using plant-virus-based nanoparticles (PVNPs) has achieved considerable success in preclinical studies. PVNP-based breast cancer therapies include non-targeted and targeted nanoplatforms for delivery of anticancer therapeutic chemo and immune agents and cancer vaccines for activation of local and systemic antitumor immunity. Interestingly, PVNP platforms combined with other tumor immunotherapeutic options and other modalities of oncotherapy can improve tumor efficacy treatment. These applications can be achieved by encapsulation of a wide range of active ingredients and conjugating ligands for targeting immune and tumor cells. This review presents the current breast cancer treatments based on PVNP platforms.

Novel Tumor-Targeting Nanoparticles for Cancer Treatment-A Review

Being one of the leading causes of death and disability worldwide, cancer represents an ongoing interdisciplinary challenge for the scientific community. As currently used treatments may face limitations in terms of both efficiency and adverse effects, continuous research has been directed towards overcoming existing challenges and finding safer specific alternatives. In particular, increasing interest has been gathered around integrating nanotechnology in cancer management and subsequentially developing various tumor-targeting nanoparticles for cancer applications. In this respect, the present paper briefly describes the most used cancer treatments in clinical practice to set a reference framework for recent research findings, further focusing on the novel developments in the field. More specifically, this review elaborates on the top recent studies concerning various nanomaterials (i.e., carbon-based, metal-based, liposomes, cubosomes, lipid-based, polymer-based, micelles, virus-based, exosomes, and cell membrane-coated nanomaterials) that show promising potential in different cancer applications.

Functionalized Protein Nanotubes Based on the Bacteriophage vB_KleM-RaK2 Tail Sheath Protein

We report on the construction of functionalized nanotubes based on tail sheath protein 041 from vB_KleM-RaK2 bacteriophage. The truncated 041 protein (041Δ200) was fused with fluorescent proteins GFP and mCherry or amidohydrolase YqfB. The generated chimeric proteins were successfully synthesized in E. coli BL21 (DE3) cells and self-assembled into tubular structures. We detected the fluorescence of the structures, which was confirmed by stimulated emission depletion microscopy. When 041Δ200GFP and 041Δ200mCherry were coexpressed in E. coli BL21 (DE3) cells, the formed nanotubes generated Förster resonance energy transfer, indicating that both fluorescent proteins assemble into a single nanotube. Chimeric 041Δ200YqfB nanotubes possessed an enzymatic activity, which was confirmed by hydrolysis of N⁴-acetyl-2′-deoxycytidine. The enzymatic properties of 041Δ200YqfB were similar to those of a free wild-type YqfB. Hence, we conclude that 041-based chimeric nanotubes have the potential for the development of delivery vehicles and targeted imaging and are applicable as scaffolds for biocatalysts.

Application of Plant Viruses in Biotechnology, Medicine, and Human Health

Plant-based nanotechnology programs using virus-like particles (VLPs) and virus nanoparticles (VNPs) are emerging platforms that are increasingly used for a variety of applications in biotechnology and medicine. Tobacco mosaic virus (TMV) and potato virus X (PVX), by virtue of having high aspect ratios, make ideal platforms for drug delivery. TMV and PVX both possess rod-shaped structures and single-stranded RNA genomes encapsidated by their respective capsid proteins and have shown great promise as drug delivery systems. Cowpea mosaic virus (CPMV) has an icosahedral structure, and thus brings unique benefits as a nanoparticle. The uses of these three plant viruses as either nanostructures or expression vectors for high value pharmaceutical proteins such as vaccines and antibodies are discussed extensively in the following review. In addition, the potential uses of geminiviruses in medical biotechnology are explored. The uses of these expression vectors in plant biotechnology applications are also discussed. Finally, in this review, we project future prospects for plant viruses in the fields of medicine, human health, prophylaxis, and therapy of human diseases.

Frontiers in Bioengineering and Biotechnology: Plant Nanoparticles for Anti-Cancer Therapy

Naturally occurring viral nanomaterials have gained popularity owing to their biocompatible and biodegradable nature. Plant virus nanoparticles (VNPs) can be used as nanocarriers for a number of biomedical applications. Plant VNPs are inexpensive to produce, safe to administer and efficacious as treatments. The following review describes how plant virus architecture facilitates the use of VNPs for imaging and a variety of therapeutic applications, with particular emphasis on cancer. Examples of plant viruses which have been engineered to carry drugs and diagnostic agents for specific types of cancer are provided. The drug delivery system in response to the internal conditions is known as stimuli response, recently becoming more applicable using plant viruses based VNPs. The review concludes with a perspective of the future of plant VNPs and plant virus-like particles (VLPs) in cancer research and therapy.

Virus as nanocarrier for drug delivery redefining medical therapeutics - A status report

Over the last two decades, drug delivery systems have evolved at a tremendous rate. Synthetic nanoparticles have played an important role in the design of vaccine and their delivery as many of them have shown improved safety and efficacy over conventional formulations. Nanocarriers formulated by natural, biological building blocks have become an important tool in the field biomedicine. A successful nanocarrier must have certain properties like evading the host immune system, target specificity, cellular entry, escape from endosomes, and ability to release material into the cytoplasm. Some or all of these functions can be performed by viruses making them a suitable candidate for naturally occurring nanocarriers. Moreover, viruses can be made non-infectious and non-replicative without compromising their ability to penetrate cells thus making them useful for a vast spectrum of applications. Currently, various carrier molecules are under different stages of development to become bio-nano capsules. This review covers the advances made in the field of viruses as potential nanocarriers and discusses the related technologies and strategies to target specific cells by using virus inspired nanocarriers. In future, these virus-based nano-formulations will be able to provide solutions towards pressing and emerging infectious diseases.

Transmembrane Peptides as a New Strategy to Inhibit Neuraminidase-1 Activation

Sialidases, or neuraminidases, are involved in several human disorders such as neurodegenerative, infectious and cardiovascular diseases, and cancers. Accumulative data have shown that inhibition of neuraminidases, such as NEU1 sialidase, may be a promising pharmacological target, and selective inhibitors of NEU1 are therefore needed to better understand the biological functions of this sialidase. In the present study, we designed interfering peptides (IntPep) that target a transmembrane dimerization interface previously identified in human NEU1 that controls its membrane dimerization and sialidase activity. Two complementary strategies were used to deliver the IntPep into cells, either flanked to a TAT sequence or non-tagged for solubilization in detergent micelles. Combined with molecular dynamics simulations and heteronuclear nuclear magnetic resonance (NMR) studies in membrane-mimicking environments, our results show that these IntPep are able to interact with the dimerization interface of human NEU1, to disrupt membrane NEU1 dimerization and to strongly decrease its sialidase activity at the plasma membrane. In conclusion, we report here new selective inhibitors of human NEU1 of strong interest to elucidate the biological functions of this sialidase.

Nanotheranostics With the Combination of Improved Targeting, Therapeutic Effects, and Molecular Imaging

There is an increasing interest in the design of targeted carrier systems with combined therapeutic and diagnostic modalities. Therapeutic modalities targeting tumors with single ligand-based targeting nanocarriers are insufficient for proficient delivery and for targeting two different surface receptors that are overexpressed in cancer cells. Here, we evaluated an activated nanoparticle delivery system comprising fucoidan/hyaluronic acid to improve therapeutic efficacy. The system comprised polyethylene glycol-gelatin-encapsulated epigallocatechin gallate (EGCG), poly (D,L-lactide-co-glycolide; PLGA), and stable iron oxide nanoparticles (IOs). The latter enables targeting of prostate cancers in their molecular images. We demonstrate the transfer of nanoparticles and their entry into prostate cancer cells through ligand-specific recognition. This system may prove the benefits of drug delivery that enhances the inhibition of cell growth through apoptosis induction. Moreover, the improved targeting of nanotheranostics significantly suppressed orthotopic prostate tumor growth and more accurately targeted tumors compared with systemic combination therapy. In the presence of nanoparticles with iron oxides, the hypointensity of the prostate tumor was visualized on a T2-weignted magnetic resonance image. The diagnostic ability of this system was demonstrated by accumulating fluorescent nanoparticles in the prostate tumor from the in vivo imaging system, computed tomography. It is suggested that theranostic nanoparticles combined with a molecular imaging system can be a promising cancer therapy in the future.

Transmembrane Peptides as Inhibitors of Protein-Protein Interactions: An Efficient Strategy to Target Cancer Cells?

Cellular functions are regulated by extracellular signals such as hormones, neurotransmitters, matrix ligands, and other chemical or physical stimuli. Ligand binding on its transmembrane receptor induced cell signaling and the recruitment of several interacting partners to the plasma membrane. Nowadays, it is well-established that the transmembrane domain is not only an anchor of these receptors to the membrane, but it also plays a key role in receptor dimerization and activation. Indeed, interactions between transmembrane helices are associated with specific biological activity of the proteins as cell migration, proliferation, or differentiation. Overexpression or constitutive dimerization (due notably to mutations) of these transmembrane receptors are involved in several physiopathological contexts as cancers. The transmembrane domain of tyrosine kinase receptors as ErbB family proteins (implicated in several cancers as HER2 in breast cancer) or other receptors as Neuropilins has been described these last years as a target to inhibit their dimerization/activation using several strategies. In this review, we will focus on the strategy which consists in using peptides to disturb in a specific manner the interactions between transmembrane domains and the signaling pathways (induced by ligand binding) of these receptors involved in cancer. This approach can be extended to inhibit other transmembrane protein dimerization as neuraminidase-1 (the catalytic subunit of elastin receptor complex), Discoidin Domain Receptor 1 (a tyrosine kinase receptor activated by type I collagen) or G-protein coupled receptors (GPCRs) which are involved in cancer processes.

Recent Advancements of Nanomedicine towards Antiangiogenic Therapy in Cancer

Angiogenesis is a process of generation of de-novo blood vessels from already existing vasculature. It has a crucial role in different physiological process including wound healing, embryonic development, and tumor growth. The methods by which therapeutic drugs inhibit tumor angiogenesis are termed as anti-angiogenesis cancer therapy. Developments of angiogenic inhibiting drugs have various limitations causing a barrier for successful treatment of cancer, where angiogenesis plays an important role. In this context, investigators developed novel strategies using nanotechnological approaches that have demonstrated inherent antiangiogenic properties or used for the delivery of antiangiogenic agents in a targeted manner. In this present article, we decisively highlight the recent developments of various nanoparticles (NPs) including liposomes, lipid NPs, protein NPs, polymer NPs, inorganic NPs, viral and bio-inspired NPs for potential application in antiangiogenic cancer therapy. Additionally, the clinical perspectives, challenges of nanomedicine, and future perspectives are briefly analyzed.