Delivery of Nucleic Acids and Nanomaterials by Cell-Penetrating Peptides: Opportunities and Challenges

Many viral and nonviral systems have been developed to aid delivery of biologically active molecules into cells. Among these, cell-penetrating peptides (CPPs) have received increasing attention in the past two decades for biomedical applications. In this review, we focus on opportunities and challenges associated with CPP delivery of nucleic acids and nanomaterials. We first describe the nature of versatile CPPs and their interactions with various types of cargoes. We then discussin vivoandin vitrodelivery of nucleic acids and nanomaterials by CPPs. Studies on the mechanisms of cellular entry and limitations in the methods used are detailed.

Download Full-text

The world of cell penetrating: the future of medical applications

Future Medicinal Chemistry ◽

10.4155/fmc-2020-0140 ◽

2020 ◽

Vol 12 (15) ◽

pp. 1431-1446 ◽

Cited By ~ 1

Author(s):

Annarita Falanga ◽

Lucia Lombardi ◽

Emilia Galdiero ◽

Valentina Del Genio ◽

Stefania Galdiero

Keyword(s):

Biomedical Applications ◽

Cell Penetrating Peptides ◽

Medical Applications ◽

Critical Factors ◽

Uptake Mechanism ◽

Cell Penetrating ◽

Effective Delivery ◽

A Cell

Cell-penetrating peptides present huge biomedical applications in a variety of pathologies, thanks to their ability to penetrate membranes and carry a variety of cargoes inside cells. Progress in peptide synthesis has produced a greater availability of virtually any synthetic peptide, increasing their attractiveness. Most molecules when associated to a cell-penetrating peptides can be delivered into a cell, however, understanding of the critical factors influencing the uptake mechanism is of paramount importance to construct nanoplatforms for effective delivery in vitro and in vivo in medical applications. Focus is now on the state-of-art of the mechanisms enabling therapeutics/diagnostics to reach the site target of their activities, and in support of scientists developing platforms for drug delivery and personalized therapies.

Download Full-text

Internalisation and Biological Activity of Nucleic Acids Delivering Cell-Penetrating Peptide Nanoparticles Is Controlled by the Biomolecular Corona

Pharmaceuticals ◽

10.3390/ph14070667 ◽

2021 ◽

Vol 14 (7) ◽

pp. 667

Author(s):

Annely Lorents ◽

Maria Maloverjan ◽

Kärt Padari ◽

Margus Pooga

Keyword(s):

Nucleic Acid ◽

Nucleic Acids ◽

Transfection Efficiency ◽

Protein Corona ◽

Blood Stream ◽

Cell Penetrating Peptides ◽

Biological Efficiency ◽

Cell Penetrating

Nucleic acid molecules can be transferred into cells to alter gene expression and, thus, alleviate certain pathological conditions. Cell-penetrating peptides (CPPs) are vectors that can be used for transfecting nucleic acids as well as many other compounds. CPPs associate nucleic acids non-covalently, forming stable nanoparticles and providing efficient transfection of cells in vitro. However, in vivo, expected efficiency is achieved only in rare cases. One of the reasons for this discrepancy is the formation of protein corona around nanoparticles, once they are exposed to a biological environment, e.g., blood stream. In this study, we compared protein corona of CPP-nucleic acid nanoparticles formed in the presence of bovine, murine and human serum. We used Western blot and mass-spectrometry to identify the major constituents of protein corona forming around nanoparticles, showing that proteins involved in transport, haemostasis and complement system are its major components. We investigated physical features of nanoparticles and measured their biological efficiency in splice-correction assay. We showed that protein corona constituents might alter the fate of nanoparticles in vivo, e.g., by subjecting them to phagocytosis. We demonstrated that composition of protein corona of nanoparticles is species-specific that leads to dissimilar transfection efficiency and should be considered while developing delivery systems for nucleic acids.

Download Full-text

Internalisation and biological activity of nucleic acids delivering cell-penetrating peptide nanoparticles is controlled by the biomolecular corona

10.1101/2021.03.26.437157 ◽

2021 ◽

Author(s):

Annely Lorents ◽

Maria Maloverjan ◽

Kärt Padari ◽

Margus Pooga

Keyword(s):

Nucleic Acid ◽

Nucleic Acids ◽

Transfection Efficiency ◽

Protein Corona ◽

Blood Stream ◽

Cell Penetrating Peptides ◽

Biological Efficiency ◽

Cell Penetrating

Nucleic acid molecules can be transferred into cells to alter gene expression and, thus, alleviate certain pathological conditions. Cell-penetrating peptides (CPPs) are vectors that can be used for transfecting nucleic acids as well as many other compounds. CPPs associate nucleic acids non-covalently, forming stable nanoparticles and providing efficient transfection of cells in vitro. However, in vivo, expected efficiency is achieved only in rare cases. One of the reasons for this discrepancy is formation of protein corona around nanoparticles, once they are exposed to a biological environment, e.g. blood stream. In this study, we compared CPP-nucleic acid nanoparticles formed in the presence of bovine, murine and human serum. We used Western blot and mass-spectrometry to identify the major constituents of protein corona forming around nanoparticles, showing that proteins involved in transport, haemostasis and complement system are its major components. We investigated physical features of nanoparticles, and measured their biological efficiency in splice-correction assay. We showed that protein corona constituents might alter the fate of nanoparticles in vivo, e.g. by subjecting them to phagocytosis. We demonstrated that composition of protein corona of nanoparticles is species-specific that leads to dissimilar transfection efficiency and should be taken into account while developing delivery systems for nucleic acids.

Download Full-text

Cell-Penetrating Peptide and siRNA-Mediated Therapeutic Effects on Endometriosis and Cancer In Vitro Models

Pharmaceutics ◽

10.3390/pharmaceutics13101618 ◽

2021 ◽

Vol 13 (10) ◽

pp. 1618

Author(s):

Kristina Kiisholts ◽

Kaido Kurrikoff ◽

Piret Arukuusk ◽

Ly Porosk ◽

Maire Peters ◽

...

Keyword(s):

Gene Therapy ◽

Cellular Proliferation ◽

Expression Patterns ◽

In Vitro Models ◽

Cell Penetrating Peptides ◽

Biologically Active ◽

Therapeutic Effects ◽

Cell Penetrating ◽

Proliferation And Invasion

Gene therapy is a powerful tool for the development of new treatment strategies for various conditions, by aiming to transport biologically active nucleic acids into diseased cells. To achieve that goal, we used highly potential delivery vectors, cell-penetrating peptides (CPPs), as oligonucleotide carriers for the development of a therapeutic approach for endometriosis and cancer. Despite marked differences, both of these conditions still exhibit similarities, like excessive, uncoordinated, and autonomous cellular proliferation and invasion, accompanied by overlapping gene expression patterns. Thus, in the current study, we investigated the therapeutic effects of CPP and siRNA nanoparticles using in vitro models of benign endometriosis and malignant glioblastoma. We demonstrated that CPPs PepFect6 and NickFect70 are highly effective in transfecting cell lines, primary cell cultures, and three-dimensional spheroids. CPP nanoparticles are capable of inducing siRNA-specific knockdown of therapeutic genes, ribonucleotide reductase subunit M2 (RRM2), and vascular endothelial growth factor (VEGF), which results in the reduction of in vitro cellular proliferation, invasion, and migration. In addition, we proved that it is possible to achieve synergistic suppression of endometriosis cellular proliferation and invasion by combining gene therapy and hormonal treatment approaches by co-administering CPP/siRNA nanoparticles together with the endometriosis-drug danazol. We suggest a novel target, RRM2, for endometriosis therapy and as a proof-of-concept, we propose a CPP-mediated gene therapy approach for endometriosis and cancer.

Download Full-text

Cell-Penetrating Peptide Modified PEG-PLA Micelles for Efficient PTX Delivery

International Journal of Molecular Sciences ◽

10.3390/ijms21051856 ◽

2020 ◽

Vol 21 (5) ◽

pp. 1856

Author(s):

Qi Shuai ◽

Yue Cai ◽

Guangkuo Zhao ◽

Xuanrong Sun

Keyword(s):

Cell Penetrating Peptides ◽

Mice Model ◽

Block Polymer ◽

Chemotherapy Drugs ◽

Tumor Tissues ◽

Cell Penetrating ◽

20 Nm ◽

Targeting Effect

On account of their excellent capacity to significantly improve the bioavailability and solubility of chemotherapy drugs, amphiphilic block copolymer-based micelles have been widely utilized for chemotherapy drug delivery. In order to further improve the antitumor ability and to also reduce undesired side effects of drugs, cell-penetrating peptides have been used to functionalize the surface of polymer micelles endowed with the ability to target tumor tissues. Herein, we first synthesized functional polyethylene glycol-polylactic acid (PEG-PLA) tethered with maleimide at the PEG section of the block polymer, which was further conjugated with a specific peptide, the transactivating transcriptional activator (TAT), with an approved capacity of aiding translocation across the plasma membrane. Then, TAT-conjugated, paclitaxel-loaded nanoparticles were self-assembled into stable nanoparticles with a favorable size of 20 nm, and displayed a significantly increased cytotoxicity, due to their enhanced accumulation via peptide-mediated cellular association in human breast cancer cells (MCF-7) in vitro. But when further used in vivo, TAT-NP-PTX showed an acceleration of the drug’s plasma clearance rate compared with NP-PTX, and therefore weakened its antitumor activities in the mice model, because of its positive charge, its elimination by the endoplasmic reticulum system more quickly, and its targeting effect on normal cells leading towards being more toxic. So further modification of TAT-NP-PTX to shield TAT peptide’s positive charges may be a hot topic to overcome the present dilemma.

Download Full-text

The anticancer efficacy of paclitaxel liposomes modified with low-toxicity hydrophobic cell-penetrating peptides in breast cancer: an in vitro and in vivo evaluation

RSC Advances ◽

10.1039/c8ra03607a ◽

2018 ◽

Vol 8 (43) ◽

pp. 24084-24093 ◽

Cited By ~ 8

Author(s):

Qi Zhang ◽

Jing Wang ◽

Hao Zhang ◽

Dan Liu ◽

Linlin Ming ◽

...

Keyword(s):

Breast Cancer ◽

Targeted Delivery ◽

Cell Penetrating Peptides ◽

Cell Penetrating Peptide ◽

In Vivo Evaluation ◽

Anticancer Efficacy ◽

Cell Penetrating ◽

Low Toxicity

Hydrophobic cell penetrating peptide PFVYLI-modified liposomes have been developed for the targeted delivery of PTX into tumors.

Download Full-text

Comparison of immunomodulatory properties of purified lactoferrin, lactoperoxidase and β-casein in sheep

Journal of Dairy Research ◽

10.1017/s0022029998003112 ◽

1998 ◽

Vol 65 (4) ◽

pp. 697-701 ◽

Cited By ~ 5

Author(s):

CHUN W. WONG ◽

DENNIS L. WATSON ◽

GEOFFREY O. REGESTER ◽

GEOFFREY W. SMITHERS

Keyword(s):

Biomedical Applications ◽

Bovine Milk ◽

Milk Proteins ◽

Biologically Active ◽

Immunological Effects ◽

Bovine Milk Proteins ◽

Proteins And Peptides

Bovine milk contains a variety of proteins and peptides that are biologically active (Ogra & Ogra, 1978; Duncan & McArthur, 1981; Newby et al. 1982; Juto, 1985; Stoeck et al. 1989; Mincheva-Nilsson et al. 1990; Watson, 1990; Barta et al. 1991; Politis et al. 1991; Fiat et al. 1993). Our laboratory has a long-term interest in some purified milk proteins, particularly lactoferrin (LF), lactoperoxidase (LP) and β-casein (β-CN), which have been shown to be immunologically significant. Some of our recent studies on these bovine milk proteins, particularly β-CN, indicated that their in vitro immunological effects did not always parallel their in vivo activities (Wong et al. 1996a, b; 1997a, b). This study was designed to investigate and compare the capacity of these purified bovine milk proteins to modulate a range of components that are vital to in vivo immune responses in sheep, with a view to providing further information on their potential in biomedical applications. To achieve this objective, a sensitive lymphatic cannulation model was employed that allows in vivo immune components and their functions to be measured in lymph collected under physiological conditions.

Download Full-text

In vitro and in vivo delivery of therapeutic proteins using cell penetrating peptides

Peptides ◽

10.1016/j.peptides.2016.11.011 ◽

2017 ◽

Vol 87 ◽

pp. 50-63 ◽

Cited By ~ 88

Author(s):

Azam Bolhassani ◽

Behnaz Sadat Jafarzade ◽

Golnaz Mardani

Keyword(s):

Therapeutic Proteins ◽

Cell Penetrating Peptides ◽

Cell Penetrating ◽

In Vivo Delivery

Download Full-text

Sialyltransferase Inhibitors for the Treatment of Cancer Metastasis: Current Challenges and Future Perspectives

Molecules ◽

10.3390/molecules26185673 ◽

2021 ◽

Vol 26 (18) ◽

pp. 5673

Author(s):

Ser John Lynon P. Perez ◽

Chih-Wei Fu ◽

Wen-Shan Li

Keyword(s):

Biomedical Applications ◽

Cancer Metastasis ◽

Future Perspectives ◽

The Past ◽

Cell Metastasis ◽

Tumor Cell Metastasis ◽

In Vivo Effects ◽

Subtype Selective

Potent, cell-permeable, and subtype-selective sialyltransferase inhibitors represent an attractive family of substances that can potentially be used for the clinical treatment of cancer metastasis. These substances operate by specifically inhibiting sialyltransferase-mediated hypersialylation of cell surface glycoproteins or glycolipids, which then blocks the sialic acid recognition pathway and leads to deterioration of cell motility and invasion. A vast amount of evidence for the in vitro and in vivo effects of sialyltransferase inhibition or knockdown on tumor progression and tumor cell metastasis or colonization has been accumulated over the past decades. In this regard, this review comprehensively discusses the results of studies that have led to the recent discovery and development of sialyltransferase inhibitors, their potential biomedical applications in the treatment of cancer metastasis, and their current limitations and future opportunities.

Download Full-text

Applications of cell-penetrating peptides in regulation of gene expression

Biochemical Society Transactions ◽

10.1042/bst0350770 ◽

2007 ◽

Vol 35 (4) ◽

pp. 770-774 ◽

Cited By ~ 30

Author(s):

P. Järver ◽

K. Langel ◽

S. El-Andaloussi ◽

Ü. Langel

Keyword(s):

Gene Expression ◽

Lipid Bilayers ◽

Regulation Of Gene Expression ◽

Cell Penetrating Peptides ◽

Remarkable Feature ◽

Cell Penetrating ◽

Plasmid Delivery ◽

Interfering Rna

CPPs (cell-penetrating peptides) can be defined as short peptides that are able to efficiently penetrate cellular lipid bilayers. Because of this remarkable feature, they are excellent candidates regarding alterations in gene expression. CPPs have been utilized in in vivo and in vitro experiments as delivery vectors for different bioactive cargoes. This review focuses on the experiments performed in recent years where CPPs have been used as vectors for multiple effectors of gene expression such as oligonucleotides for antisense, siRNA (small interfering RNA) and decoy dsDNA (double-stranded DNA) applications, and as transfection agents for plasmid delivery.

Download Full-text