1
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Clausse V, Zheng H, Amarasekara H, Kruhlak M, Appella DH. Thyclotides, tetrahydrofuran-modified peptide nucleic acids that efficiently penetrate cells and inhibit microRNA-21. Nucleic Acids Res 2022; 50:10839-10856. [PMID: 36215040 DOI: 10.1093/nar/gkac864] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Revised: 09/14/2022] [Accepted: 09/26/2022] [Indexed: 11/12/2022] Open
Abstract
Peptide nucleic acids (PNAs) are promising therapeutic molecules for gene modulation; however, they suffer from poor cell uptake. Delivery of PNAs into cells requires conjugation of the PNA to another large molecule, typically a cell-penetrating peptide or nanoparticle. In this study, we describe a new PNA-based molecule with cyclic tetrahydrofuran (THF) backbone modifications that in some cases considerably improve cell uptake. We refer to these THF-PNA oligomers as thyclotides. With THF groups at every position of the oligomer, the cell uptake of thyclotides targeted to miR-21 is enhanced compared with the corresponding unmodified PNA based on an aminoethylglycine backbone. An optimized thyclotide can efficiently enter cells without the use of cell-penetrating peptides, bind miR-21, its designated microRNA target, decrease expression of miR-21 and increase expression of three downstream targets (PTEN, Cdc25a and KRIT1). Using a plasmid with the PTEN-3'UTR coupled with luciferase, we further confirmed that a miR-21-targeted thyclotide prevents miR-21 from binding to its target RNA. Additionally, the thyclotide shows no cytotoxicity when administered at 200 times its active concentration. We propose that thyclotides be further explored as therapeutic candidates to modulate miRNA levels.
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Affiliation(s)
- Victor Clausse
- Synthetic Bioactive Molecules Section, Laboratory of Bioorganic Chemistry, NIDDK, National Institutes of Health, Bethesda, MD 20892, USA
| | - Hongchao Zheng
- Synthetic Bioactive Molecules Section, Laboratory of Bioorganic Chemistry, NIDDK, National Institutes of Health, Bethesda, MD 20892, USA
| | - Harsha Amarasekara
- Synthetic Bioactive Molecules Section, Laboratory of Bioorganic Chemistry, NIDDK, National Institutes of Health, Bethesda, MD 20892, USA
| | - Michael Kruhlak
- Microscopy Core Facility, Center for Cancer Research, NCI, National Institutes of Health, Bethesda, MD 20892, USA
| | - Daniel H Appella
- Synthetic Bioactive Molecules Section, Laboratory of Bioorganic Chemistry, NIDDK, National Institutes of Health, Bethesda, MD 20892, USA
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2
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Cadoni E, Pennati F, Muangkaew P, Elskens J, Madder A, Manicardi A. Synthesis and structure-activity relationship of peptide nucleic acid probes with improved interstrand-crosslinking abilities: application to biotin-mediated RNA-pulldown. RSC Chem Biol 2022; 3:1129-1143. [PMID: 36128507 PMCID: PMC9428673 DOI: 10.1039/d2cb00095d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Accepted: 07/18/2022] [Indexed: 11/21/2022] Open
Abstract
The development of interstrand-crosslinking (ICL) probes for the covalent targeting of DNA and RNA sequences of interest has been extensively reported in the past decade. However, most of the reactions reported so far induce the formation of a stable adduct that cannot be reverted, thus rendering these chemistries less useful in applications where the reversibility of the reaction is needed for further downstream processing of the targeted and isolated sequences, such as enzymatic amplification steps. In this work, we report on the reversibility of the furan-mediated ICL reaction. ICL formation can be conveniently triggered by either chemical (N-bromo succinimide, NBS) or luminous stimuli (visible light irradiation in presence of a photosensitizer) and quantitative reversion can be achieved by heating the crosslinked sample at 95 °C, while maintaining the structure of the DNA/RNA targets intact. As a proof-of-concept and showing the benefits of the ICL reversibility, we apply furan-mediated ICL to the pulldown of a target RNA strand from cell lysate.
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Affiliation(s)
- Enrico Cadoni
- Organic and Biomimetic Chemistry Research Group, Department of Organic and Macromolecular Chemistry, Ghent University Krijgslaan 281-7 9000 Gent Belgium
| | - Francesca Pennati
- Organic and Biomimetic Chemistry Research Group, Department of Organic and Macromolecular Chemistry, Ghent University Krijgslaan 281-7 9000 Gent Belgium
| | - Penthip Muangkaew
- Organic and Biomimetic Chemistry Research Group, Department of Organic and Macromolecular Chemistry, Ghent University Krijgslaan 281-7 9000 Gent Belgium
- Organic Synthesis Research Unit, Department of Chemistry, Faculty of Science, Chulalongkorn University Phayathai Road Patumwan 10330 Bangkok Thailand
| | - Joke Elskens
- Organic and Biomimetic Chemistry Research Group, Department of Organic and Macromolecular Chemistry, Ghent University Krijgslaan 281-7 9000 Gent Belgium
| | - Annemieke Madder
- Organic and Biomimetic Chemistry Research Group, Department of Organic and Macromolecular Chemistry, Ghent University Krijgslaan 281-7 9000 Gent Belgium
| | - Alex Manicardi
- Organic and Biomimetic Chemistry Research Group, Department of Organic and Macromolecular Chemistry, Ghent University Krijgslaan 281-7 9000 Gent Belgium
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3
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Suparpprom C, Vilaivan T. Perspectives on conformationally constrained peptide nucleic acid (PNA): insights into the structural design, properties and applications. RSC Chem Biol 2022; 3:648-697. [PMID: 35755191 PMCID: PMC9175113 DOI: 10.1039/d2cb00017b] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Accepted: 03/17/2022] [Indexed: 11/21/2022] Open
Abstract
Peptide nucleic acid or PNA is a synthetic DNA mimic that contains a sequence of nucleobases attached to a peptide-like backbone derived from N-2-aminoethylglycine. The semi-rigid PNA backbone acts as a scaffold that arranges the nucleobases in a proper orientation and spacing so that they can pair with their complementary bases on another DNA, RNA, or even PNA strand perfectly well through the standard Watson-Crick base-pairing. The electrostatically neutral backbone of PNA contributes to its many unique properties that make PNA an outstanding member of the xeno-nucleic acid family. Not only PNA can recognize its complementary nucleic acid strand with high affinity, but it does so with excellent specificity that surpasses the specificity of natural nucleic acids and their analogs. Nevertheless, there is still room for further improvements of the original PNA in terms of stability and specificity of base-pairing, direction of binding, and selectivity for different types of nucleic acids, among others. This review focuses on attempts towards the rational design of new generation PNAs with superior performance by introducing conformational constraints such as a ring or a chiral substituent in the PNA backbone. A large collection of conformationally rigid PNAs developed during the past three decades are analyzed and compared in terms of molecular design and properties in relation to structural data if available. Applications of selected modified PNA in various areas such as targeting of structured nucleic acid targets, supramolecular scaffold, biosensing and bioimaging, and gene regulation will be highlighted to demonstrate how the conformation constraint can improve the performance of the PNA. Challenges and future of the research in the area of constrained PNA will also be discussed.
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Affiliation(s)
- Chaturong Suparpprom
- Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Naresuan University, Tah-Poe District, Muang Phitsanulok 65000 Thailand
- Organic Synthesis Research Unit, Department of Chemistry, Faculty of Science, Chulalongkorn University Phayathai Road Pathumwan Bangkok 10330 Thailand
| | - Tirayut Vilaivan
- Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Naresuan University, Tah-Poe District, Muang Phitsanulok 65000 Thailand
- Organic Synthesis Research Unit, Department of Chemistry, Faculty of Science, Chulalongkorn University Phayathai Road Pathumwan Bangkok 10330 Thailand
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4
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Zaccagnini G, Greco S, Voellenkle C, Gaetano C, Martelli F. miR-210 hypoxamiR in Angiogenesis and Diabetes. Antioxid Redox Signal 2022; 36:685-706. [PMID: 34521246 DOI: 10.1089/ars.2021.0200] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Significance: microRNA-210 (miR-210) is the master hypoxia-inducible miRNA (hypoxamiR) since it has been found to be significantly upregulated under hypoxia in a wide range of cell types. Recent advances: Gene ontology analysis of its targets indicates that miR-210 modulates several aspects of cellular response to hypoxia. Due to its high pleiotropy, miR-210 not only plays a protective role by fine-tuning mitochondrial metabolism and inhibiting red-ox imbalance and apoptosis, but it can also promote cell proliferation, differentiation, and migration, substantially contributing to angiogenesis. Critical issues: As most miRNAs, modulating different gene pathways, also miR-210 can potentially lead to different and even opposite effects, depending on the physio-pathological contexts in which it acts. Future direction: The use of miRNAs as therapeutics is a fast growing field. This review aimed at highlighting the role of miR-210 in angiogenesis in the context of ischemic cardiovascular diseases and diabetes in order to clarify the molecular mechanisms underpinning miR-210 action. Particular attention will be dedicated to experimentally validated miR-210 direct targets involved in cellular processes related to angiogenesis and diabetes mellitus, such as mitochondrial metabolism, redox balance, apoptosis, migration, and adhesion. Antioxid. Redox Signal. 36, 685-706.
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Affiliation(s)
- Germana Zaccagnini
- Molecular Cardiology Laboratory, IRCCS Policlinico San Donato, San Donato Milanese, Italy
| | - Simona Greco
- Molecular Cardiology Laboratory, IRCCS Policlinico San Donato, San Donato Milanese, Italy
| | - Christine Voellenkle
- Molecular Cardiology Laboratory, IRCCS Policlinico San Donato, San Donato Milanese, Italy
| | - Carlo Gaetano
- Laboratorio di Epigenetica, Istituti Clinici Scientifici Maugeri IRCCS, Pavia, Italy
| | - Fabio Martelli
- Molecular Cardiology Laboratory, IRCCS Policlinico San Donato, San Donato Milanese, Italy
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5
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Brodyagin N, Kataoka Y, Kumpina I, McGee DW, Rozners E. Cellular uptake of 2-aminopyridine-modified peptide nucleic acids conjugated with cell-penetrating peptides. Biopolymers 2021; 113:e23484. [PMID: 34914092 DOI: 10.1002/bip.23484] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Revised: 11/30/2021] [Accepted: 12/06/2021] [Indexed: 01/31/2023]
Abstract
Cell-penetrating peptides (CPPs) have been extensively used to deliver peptide nucleic acid (PNA) in cells. We have previously found that replacement of cytosine in triplex-forming PNAs with 2-aminopyridine (M) not only enhanced RNA binding, but also improved cellular uptake of PNAs. In this study, we used confocal fluorescence microscopy to evaluate the ability of CPPs to further improve cellular uptake of M-modified PNAs. We found that PNAs conjugated with Tat and octa-arginine peptides were effectively taken up in MCF7 cells when supplied in cell media at 1 μM. Remarkably, M-modified PNA without any CPP conjugation also showed strong uptake when the concentration was increased to 5 μM. Majority of PNA conjugates remained localized in distinct cytoplasmic vesicles, as judged by dot-like fluorescence patterns. However, M-modified PNAs conjugated with Tat, octa-arginine, and even a simple tri-lysine peptide also showed dispersed fluorescence in cytoplasm and were taken up in nuclei where they localized in larger vesicles, most likely nucleoli. Endosomolytic peptides or chemicals (chloroquine and CaCl2 ) did not release the conjugates from cytosolic vesicles, which suggested that the PNAs were not entrapped in endosomes. We hypothesize that M-modified PNAs escape endosomes and accumulate in cellular compartments rich in RNA, such as nucleoli, stress granules, and P-bodies.
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Affiliation(s)
- Nikita Brodyagin
- Department of Chemistry, Binghamton University, The State University of New York, Binghamton, New York, USA
| | - Yuka Kataoka
- Department of Chemistry, Binghamton University, The State University of New York, Binghamton, New York, USA
| | - Ilze Kumpina
- Department of Chemistry, Binghamton University, The State University of New York, Binghamton, New York, USA
| | - Dennis W McGee
- Department of Biological Sciences, Binghamton University, The State University of New York, Binghamton, New York, USA
| | - Eriks Rozners
- Department of Chemistry, Binghamton University, The State University of New York, Binghamton, New York, USA
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6
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Extracellular vesicles mediated exocytosis of antisense peptide nucleic acids. MOLECULAR THERAPY. NUCLEIC ACIDS 2021; 25:302-315. [PMID: 34458012 PMCID: PMC8379631 DOI: 10.1016/j.omtn.2021.07.018] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Accepted: 07/27/2021] [Indexed: 12/19/2022]
Abstract
Peptide nucleic acids (PNAs), a synthetic DNA mimic, have been extensively utilized for antisense- and antigene-based biomedical applications. Significant efforts have been made to increase the cellular uptake of PNAs, but here we examined relatively unexplored aspects of intracellular trafficking and endocytic recycling of PNAs. For proof-of-concept, we used anti-microRNA (miR) PNA targeting miR-155. The sub-cellular localization of PNA was studied via confocal and flow-cytometry-based assays in HeLa cells. A comprehensive characterization of PNA-containing extracellular vesicles revealed spherical morphology, negative surface charge density, and the presence of tetraspanin markers. Most importantly, we investigated rab11a and rab27b GTPases' role in regulating the exocytosis of PNAs. Organelle staining, followed by confocal imaging, showed higher localization of PNA in lysosomes. Gene-expression analysis established the enhanced functional activity of PNA after inhibition of endocytic recycling. Multiple studies report the exocytosis of single-stranded oligonucleotides, short interfering RNAs (siRNAs), and nanocarriers. To our knowledge, this is the first mechanistic study to establish that PNA undergoes endocytic recycling and exocytosis out of tumor cells. The results presented here can serve as a platform to develop and optimize strategies for improving the therapeutic efficacy of PNAs by avoiding the recycling pathways.
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7
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Rastgar Rezaei Y, Zarezadeh R, Nikanfar S, Oghbaei H, Nazdikbin N, Bahrami-Asl Z, Zarghami N, Ahmadi Y, Fattahi A, Nouri M, Dittrich R. microRNAs in the pathogenesis of non-obstructive azoospermia: the underlying mechanisms and therapeutic potentials. Syst Biol Reprod Med 2021; 67:337-353. [PMID: 34355990 DOI: 10.1080/19396368.2021.1951890] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
miRNAs are involved in different biological processes, including proliferation, differentiation, and apoptosis. Interestingly, 38% of the X chromosome-linked miRNAs are testis-specific and have crucial roles in regulating the renewal and cell cycle of spermatogonial stem cells. Previous studies demonstrated that abnormal expression of spermatogenesis-related miRNAs could lead to nonobstructive azoospermia (NOA). Moreover, differential miRNAs expression in seminal plasma of NOA patients has been reported compared to normozoospermic men. However, the role of miRNAs in NOA pathogenesis and the underlying mechanisms have not been comprehensively studied. Therefore, the aim of this review is to mechanistically describe the role of miRNAs in the pathogenesis of NOA and discuss the possibility of using the miRNAs as therapeutic targets.Abbreviations: AMO: anti-miRNA antisense oligonucleotide; AZF: azoospermia factor region; CDK: cyclin-dependent kinase; DAZ: deleted in azoospermia; ESCs: embryonic stem cells; FSH: follicle-stimulating hormone; ICSI: intracytoplasmic sperm injection; JAK/STAT: Janus kinase/signal transducers and activators of transcription; miRNA: micro-RNA; MLH1: Human mutL homolog l; NF-κB: Nuclear factor-kappa B; NOA: nonobstructive azoospermia; OA: obstructive azoospermia; PGCs: primordial germ cells; PI3K/AKT: Phosphatidylinositol 3-kinase/protein kinase B; Rb: retinoblastoma tumor suppressor; ROS: Reactive Oxygen Species; SCOS: Sertoli cell-only syndrome; SIRT: sirtuin; SNPs: single nucleotide polymorphisms; SSCs: spermatogonial stem cells; TESE: testicular sperm extraction; TGF-β: transforming growth factor-beta.
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Affiliation(s)
- Yeganeh Rastgar Rezaei
- Stem Cell Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.,Department of Medical Biotechnology, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Reza Zarezadeh
- Department of Biochemistry and Clinical Laboratories, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Saba Nikanfar
- Department of Biochemistry and Clinical Laboratories, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran.,Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Hajar Oghbaei
- Department of Physiology, Tabriz University of Medical Sciences, Tabriz, Iran
| | | | - Zahra Bahrami-Asl
- Women's Reproductive Health Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Nosratollah Zarghami
- Department of Medical Biotechnology, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Yadollah Ahmadi
- Department of Urology, Sina Hospital, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Amir Fattahi
- Stem Cell Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.,Department of Reproductive Biology, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran.,Department of Obstetrics and Gynecology, Erlangen University Hospital, Friedrich-Alexander University of Erlangen-Nürnberg, Erlangen, Germany
| | - Mohammad Nouri
- Stem Cell Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.,Department of Medical Biotechnology, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Ralf Dittrich
- Department of Obstetrics and Gynecology, Erlangen University Hospital, Friedrich-Alexander University of Erlangen-Nürnberg, Erlangen, Germany
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8
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Winkle M, El-Daly SM, Fabbri M, Calin GA. Noncoding RNA therapeutics - challenges and potential solutions. Nat Rev Drug Discov 2021; 20:629-651. [PMID: 34145432 PMCID: PMC8212082 DOI: 10.1038/s41573-021-00219-z] [Citation(s) in RCA: 770] [Impact Index Per Article: 256.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/27/2021] [Indexed: 02/07/2023]
Abstract
Therapeutic targeting of noncoding RNAs (ncRNAs), such as microRNAs (miRNAs) and long noncoding RNAs (lncRNAs), represents an attractive approach for the treatment of cancers, as well as many other diseases. Over the past decade, substantial effort has been made towards the clinical application of RNA-based therapeutics, employing mostly antisense oligonucleotides and small interfering RNAs, with several gaining FDA approval. However, trial results have so far been ambivalent, with some studies reporting potent effects whereas others demonstrated limited efficacy or toxicity. Alternative entities such as antimiRNAs are undergoing clinical testing, and lncRNA-based therapeutics are gaining interest. In this Perspective, we discuss key challenges facing ncRNA therapeutics - including issues associated with specificity, delivery and tolerability - and focus on promising emerging approaches that aim to boost their success.
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Affiliation(s)
- Melanie Winkle
- Translational Molecular Pathology, MD Anderson Cancer Center, Texas State University, Houston, TX, USA
| | - Sherien M El-Daly
- Medical Biochemistry Department, Medical Research Division - Cancer Biology and Genetics Laboratory, Centre of Excellence for Advanced Sciences - National Research Centre, Cairo, Egypt
| | - Muller Fabbri
- Cancer Biology Program, University of Hawaii Cancer Center, Honolulu, HI, USA
| | - George A Calin
- Translational Molecular Pathology, MD Anderson Cancer Center, Texas State University, Houston, TX, USA.
- The RNA Interference and Non-codingRNA Center, MD Anderson Cancer Center, Texas State University, Houston, TX, USA.
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9
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Brodyagin N, Katkevics M, Kotikam V, Ryan CA, Rozners E. Chemical approaches to discover the full potential of peptide nucleic acids in biomedical applications. Beilstein J Org Chem 2021; 17:1641-1688. [PMID: 34367346 PMCID: PMC8313981 DOI: 10.3762/bjoc.17.116] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Accepted: 06/28/2021] [Indexed: 12/23/2022] Open
Abstract
Peptide nucleic acid (PNA) is arguably one of the most successful DNA mimics, despite a most dramatic departure from the native structure of DNA. The present review summarizes 30 years of research on PNA's chemistry, optimization of structure and function, applications as probes and diagnostics, and attempts to develop new PNA therapeutics. The discussion starts with a brief review of PNA's binding modes and structural features, followed by the most impactful chemical modifications, PNA enabled assays and diagnostics, and discussion of the current state of development of PNA therapeutics. While many modifications have improved on PNA's binding affinity and specificity, solubility and other biophysical properties, the original PNA is still most frequently used in diagnostic and other in vitro applications. Development of therapeutics and other in vivo applications of PNA has notably lagged behind and is still limited by insufficient bioavailability and difficulties with tissue specific delivery. Relatively high doses are required to overcome poor cellular uptake and endosomal entrapment, which increases the risk of toxicity. These limitations remain unsolved problems waiting for innovative chemistry and biology to unlock the full potential of PNA in biomedical applications.
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Affiliation(s)
- Nikita Brodyagin
- Department of Chemistry, Binghamton University, The State University of New York, Binghamton, New York 13902, United States
| | - Martins Katkevics
- Latvian Institute of Organic Synthesis, Aizkraukles 21, Riga, LV-1006, Latvia
| | - Venubabu Kotikam
- Department of Chemistry, Binghamton University, The State University of New York, Binghamton, New York 13902, United States
| | - Christopher A Ryan
- Department of Chemistry, Binghamton University, The State University of New York, Binghamton, New York 13902, United States
| | - Eriks Rozners
- Department of Chemistry, Binghamton University, The State University of New York, Binghamton, New York 13902, United States
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10
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Liang X, Liu M, Komiyama M. Recognition of Target Site in Various Forms of DNA and RNA by Peptide Nucleic Acid (PNA): From Fundamentals to Practical Applications. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2021. [DOI: 10.1246/bcsj.20210086] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Xingguo Liang
- College of Food Science and Engineering, Ocean University of China, Qingdao 266003, P. R. China
- Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology, Qingdao 266235, P. R. China
| | - Mengqin Liu
- College of Food Science and Engineering, Ocean University of China, Qingdao 266003, P. R. China
| | - Makoto Komiyama
- College of Food Science and Engineering, Ocean University of China, Qingdao 266003, P. R. China
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11
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Finotti A, Gasparello J, Casnati A, Corradini R, Gambari R, Sansone F. Delivery of Peptide Nucleic Acids Using an Argininocalix[4]arene as Vector. Methods Mol Biol 2021; 2211:123-143. [PMID: 33336275 DOI: 10.1007/978-1-0716-0943-9_10] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
The importance of peptide nucleic acids (PNAs) for alteration of gene expression is nowadays firmly established. PNAs are characterized by a pseudo-peptide backbone composed of N-(2-aminoethyl)glycine units and have been found to be excellent candidates for antisense and antigene therapies. Recently, PNAs have been demonstrated to alter the action of microRNAs and thus can be considered very important tools for miRNA therapeutics. In fact, the pharmacological modulation of microRNA activity appears to be a very interesting approach in the development of new types of drugs. Among the limits of PNAs in applied molecular biology, the delivery to target cells and tissues is of key importance. The aim of this chapter is to describe methods for the efficient delivery of unmodified PNAs designed to target microRNAs involved in cancer, using as model system miR-221-3p and human glioma cells as in vitro experimental cellular system. The methods employed to deliver PNAs targeting miR-221-3p here presented are based on a macrocyclic multivalent tetraargininocalix[4]arene used as non-covalent vector for anti-miR-221-3p PNAs. High delivery efficiency, low cytotoxicity, maintenance of the PNA biological activity, and easy preparation makes this vector a candidate for a universal delivery system for this class of nucleic acid analogs.
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Affiliation(s)
- Alessia Finotti
- Section of Biochemistry and Molecular Biology, Department of Life Sciences and Biotechnology, Ferrara University, Ferrara, Italy.
| | - Jessica Gasparello
- Section of Biochemistry and Molecular Biology, Department of Life Sciences and Biotechnology, Ferrara University, Ferrara, Italy
| | - Alessandro Casnati
- Department of Chemistry, Life Sciences and Environmental Sustainability, Parma University, Parma, Italy
| | - Roberto Corradini
- Department of Chemistry, Life Sciences and Environmental Sustainability, Parma University, Parma, Italy
| | - Roberto Gambari
- Section of Biochemistry and Molecular Biology, Department of Life Sciences and Biotechnology, Ferrara University, Ferrara, Italy.,Interuniversity Consortium for Biotechnology, Trieste University, Trieste, Italy
| | - Francesco Sansone
- Department of Chemistry, Life Sciences and Environmental Sustainability, Parma University, Parma, Italy.
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12
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Volpi S, Rozzi A, Rivi N, Neri M, Knoll W, Corradini R. Submonomeric Strategy with Minimal Protection for the Synthesis of C(2)-Modified Peptide Nucleic Acids. Org Lett 2021; 23:902-907. [PMID: 33417460 PMCID: PMC7880566 DOI: 10.1021/acs.orglett.0c04116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2020] [Indexed: 11/28/2022]
Abstract
A novel synthesis of C(2)-modified peptide nucleic acids (PNAs) is proposed, using a submonomeric strategy with minimally protected building blocks, which allowed a reduction in the required synthetic steps. N(3)-unprotected, d-Lys- and d-Arg-based backbones were used to obtain positively charged PNAs with high optical purity, as inferred from chiral GC measurements. "Chiral-box" PNAs targeting the G12D point mutation of the KRAS gene were produced using this method, showing improved sequence selectivity for the mutated- vs wild-type DNA strand with respect to unmodified PNAs.
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Affiliation(s)
- Stefano Volpi
- Department
of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 17/A, Parma, 43123, Italy
| | - Andrea Rozzi
- Department
of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 17/A, Parma, 43123, Italy
| | - Nicola Rivi
- Department
of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 17/A, Parma, 43123, Italy
| | - Martina Neri
- Department
of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 17/A, Parma, 43123, Italy
| | - Wolfgang Knoll
- Department
of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 17/A, Parma, 43123, Italy
- Biosensor
Technologies, AIT-Austrian Institute of Technology GmbH, Konrad-Lorenz-Straße 24, 3430, Tulln an der Donau, Austria
| | - Roberto Corradini
- Department
of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 17/A, Parma, 43123, Italy
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13
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Abstract
The involvement of microRNAs in human pathologies is firmly established. Accordingly, the pharmacological modulation of microRNA activity appears to be a very interesting approach in the development of new types of drugs (miRNA therapeutics). One important research area is the possible development of miRNA therapeutics in the field of rare diseases. In this respect, appealing molecules are based on peptide nucleic acids (PNAs), displaying, in their first description, a pseudo-peptide backbone composed of N-(2-aminoethyl)glycine units, and found to be excellent candidates for antisense and antigene therapies. The aim of the present article is to describe methods for determining the activity of PNAs designed to target microRNAs involved in cystic fibrosis, using as model system miR-145-5p and its target cystic fibrosis transmembrane conductance regulator (CFTR) mRNA. The methods employed to study the effects of PNAs targeting miR-145-5p are presented here by discussing data obtained using as cellular model system the human lung epithelial Calu-3 cell line.
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14
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Das A, Pradhan B. Evolution of peptide nucleic acid with modifications of its backbone and application in biotechnology. Chem Biol Drug Des 2020; 97:865-892. [PMID: 33314595 DOI: 10.1111/cbdd.13815] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Revised: 11/17/2020] [Accepted: 12/05/2020] [Indexed: 01/23/2023]
Abstract
Peptide nucleic acids (PNAs) are getting prodigious interest currently in the biomedical and diagnostic field as an extremely powerful tool because of their potentiality to hybridize with natural nucleic acids. Although PNA has strong affinity and sequence specificity to DNA/RNA, there is a considerable ongoing effort to further enhance their special chemical and biological properties for potential application in numerous fields, notably in the field of therapeutics. The toolbox for backbone modified PNAs synthesis has been extended substantially in recent decades, providing a more efficient synthesis of peptides with numerous scaffolds and modifications. This paper reviews the various strategies that have been developed so far for the modification of the PNA backbone, challenging the search for new PNA systems with improved chemical and physical properties lacking in the original aegPNA backbone. The various practical issues and limitations of different PNA systems are also summarized. The focus of this review is on the evolution of PNA by its backbone modification to improve the cellular uptake, sequence specificity, and compatibility of PNA to bind to DNA/RNA. Finally, an insight was also gained into major applications of backbone modified PNAs for the development of biosensors.
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Affiliation(s)
- Anuradha Das
- National Institute of Science Education and Research Bhubaneswar (HBNI), Bhubaneswar, India
| | - Biswaranjan Pradhan
- S. K. Dash Center of Excellence of Biosciences and Engineering & Technology, Indian Institute of Technology Bhubaneswar, Bhubaneswar, India
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15
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Direct plasmonic detection of circulating RAS mutated DNA in colorectal cancer patients. Biosens Bioelectron 2020; 170:112648. [PMID: 33010708 DOI: 10.1016/j.bios.2020.112648] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 09/01/2020] [Accepted: 09/21/2020] [Indexed: 12/11/2022]
Abstract
RAS mutations in the blood of colorectal cancer (CRC) patients are emerging as biomarkers of acquired resistance to Epidermal Growth Factor Receptor therapy. Unfortunately, reliable assays granting fast, real-time monitoring of treatment response, capable of refining retrospective, tissue-based analysis, are still needed. Recently, several methods for detecting blood RAS mutations have been proposed, generally relying on multi-step and PCR-based, time-consuming and cost-ineffective procedures. By exploiting a liquid biopsy approach, we developed an ultrasensitive nanoparticle-enhanced plasmonic method for detecting ~1 aM RAS single nucleotide variants (SNVs) in the plasma of CRC patients. The assay does not require the extraction of tumor DNA from plasma and detects it in volumes as low as 40 μL of plasma, which is at least an order of magnitude smaller than that required by state of the art liquid biopsy technologies. The most prevalent RAS mutations are detected in DNA from tumor tissue with 100% sensitivity and 83.33% specificity. Spike-in experiments in human plasma further encouraged assay application on clinical specimens. The assay was proven in plasma from CRC patients and healthy donors, and full discrimination between mutated DNA from patients over wild-type DNA from healthy volunteers was obtained thus demonstrating its promising avenue for cancer monitoring based on liquid biopsy.
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16
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Swenson CS, Heemstra JM. Peptide nucleic acids harness dual information codes in a single molecule. Chem Commun (Camb) 2020; 56:1926-1935. [PMID: 32009137 DOI: 10.1039/c9cc09905k] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Nature encodes the information required for life in two fundamental biopolymers: nucleic acids and proteins. Peptide nucleic acid (PNA), a synthetic analog comprised of nucleobases arrayed along a pseudopeptide backbone, has the ability to combine the power of nucleic acids to encode information with the versatility of amino acids to encode structure and function. Historically, PNA has been perceived as a simple nucleic acid mimic having desirable properties such as high biostability and strong affinity for complementary nucleic acids. In this feature article, we aim to adjust this perception by highlighting the ability of PNA to act as a peptide mimic and showing the largely untapped potential to encode information in the amino acid sequence. First, we provide an introduction to PNA and discuss the use of conjugation to impart tunable properties to the biopolymer. Next, we describe the integration of functional groups directly into the PNA backbone to impart specific physical properties. Lastly, we highlight the use of these integrated amino acid side chains to encode peptide-like sequences in the PNA backbone, imparting novel activity and function and demonstrating the ability of PNA to simultaneously mimic both a peptide and a nucleic acid.
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Affiliation(s)
- Colin S Swenson
- Department of Chemistry, Emory University, Atlanta, Georgia 30322, USA.
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17
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Swenson CS, Velusamy A, Argueta-Gonzalez HS, Heemstra JM. Bilingual Peptide Nucleic Acids: Encoding the Languages of Nucleic Acids and Proteins in a Single Self-Assembling Biopolymer. J Am Chem Soc 2019; 141:19038-19047. [PMID: 31711285 DOI: 10.1021/jacs.9b09146] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Nucleic acids and proteins are the fundamental biopolymers that support all life on Earth. Nucleic acids store large amounts of information in nucleobase sequences while peptides and proteins utilize diverse amino acid functional groups to adopt complex structures and perform wide-ranging activities. Although nature has evolved machinery to read the nucleic acid code and translate it into amino acid code, the extant biopolymers are restricted to encoding amino acid or nucleotide sequences separately, limiting their potential applications in medicine and biotechnology. Here we describe the design, synthesis, and stimuli-responsive assembly behavior of a bilingual biopolymer that integrates both amino acid and nucleobase sequences into a single peptide nucleic acid (PNA) scaffold to enable tunable storage and retrieval of tertiary structural behavior and programmable molecular recognition capabilities. Incorporation of a defined sequence of amino acid side-chains along the PNA backbone yields amphiphiles having a "protein code" that directs self-assembly into micellar architectures in aqueous conditions. However, these amphiphiles also carry a "nucleotide code" such that subsequent introduction of a complementary RNA strand induces a sequence-specific disruption of assemblies through hybridization. Together, these properties establish bilingual PNA as a powerful biopolymer that combines two information systems to harness structural responsiveness and sequence recognition. The PNA scaffold and our synthetic system are highly generalizable, enabling fabrication of a wide array of user-defined peptide and nucleotide sequence combinations for diverse future biomedical and nanotechnology applications.
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Affiliation(s)
- Colin S Swenson
- Department of Chemistry , Emory University , Atlanta , Georgia 30322 , United States
| | - Arventh Velusamy
- Department of Chemistry , Emory University , Atlanta , Georgia 30322 , United States
| | | | - Jennifer M Heemstra
- Department of Chemistry , Emory University , Atlanta , Georgia 30322 , United States
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18
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Tähtinen V, Verhassel A, Tuomela J, Virta P. γ-(S)-Guanidinylmethyl-Modified Triplex-Forming Peptide Nucleic Acids Increase Hoogsteen-Face Affinity for a MicroRNA and Enhance Cellular Uptake. Chembiochem 2019; 20:3041-3051. [PMID: 31206960 DOI: 10.1002/cbic.201900393] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Indexed: 12/14/2022]
Abstract
γ-Modified (i.e., (S)-aminomethyl, (S)-acetamidomethyl, (R)-4-(hydroxymethyl)triazol-1-ylmethyl, and (S)-guanidinylmethyl) triplex-forming peptide nucleic acids (TFPNAs) were synthesized and the effect of the backbone modifications on the binding to a miR-215 model was studied. Among the modifications, an appropriate pattern of three γ-(S)-guanidinylmethyl modifications increased the affinity and Hoogsteen-face selectivity for the miR-215 model without ternary (PNA)2 /RNA complex formation. Moreover, the γ-(S)-guanidinylmethyl groups were observed to facilitate internalization of the TFPNAs into living PC-3 prostate cancer cells.
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Affiliation(s)
- Ville Tähtinen
- Department of Chemistry, University of Turku, Vatselankatu 2, 20014, Turku, Finland
| | - Alejandra Verhassel
- FICAN West Cancer Research Laboratory, University of Turku and Turku University Hospital, Institution of Biomedicine, Medisiina D, Kiinamyllynkatu 10, 20520, Turku, Finland
| | - Johanna Tuomela
- FICAN West Cancer Research Laboratory, University of Turku and Turku University Hospital, Institution of Biomedicine, Medisiina D, Kiinamyllynkatu 10, 20520, Turku, Finland
| | - Pasi Virta
- Department of Chemistry, University of Turku, Vatselankatu 2, 20014, Turku, Finland
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19
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Saarbach J, Sabale PM, Winssinger N. Peptide nucleic acid (PNA) and its applications in chemical biology, diagnostics, and therapeutics. Curr Opin Chem Biol 2019; 52:112-124. [PMID: 31541865 DOI: 10.1016/j.cbpa.2019.06.006] [Citation(s) in RCA: 121] [Impact Index Per Article: 24.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Revised: 05/07/2019] [Accepted: 06/06/2019] [Indexed: 12/11/2022]
Abstract
Peptide nucleic acid (PNA) stands as one of the most successful artificial oligonucleotide mimetics. Salient features include the stability of hybridization complexes (either as duplexes or triplexes), metabolic stability, and ease of chemical modifications. These features have enabled important applications such as antisense agents, gene editing, nucleic acid sensing and as a platform to program the assembly of PNA-tagged molecules. Here, we review recent advances in these areas.
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Affiliation(s)
- Jacques Saarbach
- Faculty of Science, Department of Organic Chemistry, NCCR Chemical Biology, University of Geneva 30 quai Ernest Ansermet, CH-1205 Geneva, Switzerland
| | - Pramod M Sabale
- Faculty of Science, Department of Organic Chemistry, NCCR Chemical Biology, University of Geneva 30 quai Ernest Ansermet, CH-1205 Geneva, Switzerland
| | - Nicolas Winssinger
- Faculty of Science, Department of Organic Chemistry, NCCR Chemical Biology, University of Geneva 30 quai Ernest Ansermet, CH-1205 Geneva, Switzerland.
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20
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Gasparello J, Papi C, Zurlo M, Corradini R, Gambari R, Finotti A. Demonstrating specificity of bioactive peptide nucleic acids (PNAs) targeting microRNAs for practical laboratory classes of applied biochemistry and pharmacology. PLoS One 2019; 14:e0221923. [PMID: 31509554 PMCID: PMC6738603 DOI: 10.1371/journal.pone.0221923] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Accepted: 08/19/2019] [Indexed: 12/26/2022] Open
Abstract
Practical laboratory classes teaching molecular pharmacology approaches employed in the development of therapeutic strategies are of great interest for students of courses in Biotechnology, Applied Biology, Pharmaceutic and Technology Chemistry, Translational Oncology. Unfortunately, in most cases the technology to be transferred to learning students is complex and requires multi-step approaches. In this respect, simple and straightforward experimental protocols might be of great interest. This study was aimed at presenting a laboratory exercise focusing (a) on a very challenging therapeutic strategy, i.e. microRNA therapeutics, and (b) on the employment of biomolecules of great interest in applied biology and pharmacology, i.e. peptide nucleic acids (PNAs). The aims of the practical laboratory were to determine: (a) the possible PNA-mediated arrest in RT-qPCR, to be eventually used to demonstrate PNA targeting of selected miRNAs; (b) the possible lack of activity on mutated PNA sequences; (c) the effects (if any) on the amplification of other unrelated miRNA sequences. The results which can be obtained support the following conclusions: PNA-mediated arrest in RT-qPCR can be analyzed in a easy way; mutated PNA sequences are completely inactive; the effects of the employed PNAs are specific and no inhibitory effect occurs on other unrelated miRNA sequences. This activity is simple (cell culture, RNA extraction, RT-qPCR are all well-established technologies), fast (starting from isolated and characterized RNA, few hours are just necessary), highly reproducible (therefore easily employed by even untrained students). On the other hand, these laboratory lessons require some facilities, the most critical being the availability of instruments for PCR. While this might be a problem in the case these instruments are not available, we would like to underline that determination of the presence or of a lack of amplified product can be also obtained using standard analytical approaches based on agarose gel electrophoresis.
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Affiliation(s)
- Jessica Gasparello
- Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy
| | - Chiara Papi
- Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy
| | - Matteo Zurlo
- Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy
| | - Roberto Corradini
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parma, Italy
| | - Roberto Gambari
- Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy
- Interuniversity Consortium for Biotechnology (CIB), Trieste, Italy
- * E-mail:
| | - Alessia Finotti
- Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy
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21
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Milani R, Brognara E, Fabbri E, Manicardi A, Corradini R, Finotti A, Gasparello J, Borgatti M, Cosenza LC, Lampronti I, Dechecchi MC, Cabrini G, Gambari R. Targeting miR‑155‑5p and miR‑221‑3p by peptide nucleic acids induces caspase‑3 activation and apoptosis in temozolomide‑resistant T98G glioma cells. Int J Oncol 2019; 55:59-68. [PMID: 31180529 PMCID: PMC6561624 DOI: 10.3892/ijo.2019.4810] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Accepted: 03/26/2019] [Indexed: 12/11/2022] Open
Abstract
The present study investigated the effects of the combined treatment of two peptide nucleic acids (PNAs), directed against microRNAs involved in caspase‑3 mRNA regulation (miR‑155‑5p and miR‑221‑3p) in the temozolomide (TMZ)‑resistant T98G glioma cell line. These PNAs were conjugated with an octaarginine tail in order to obtain an efficient delivery to treated cells. The effects of singularly administered PNAs or a combined treatment with both PNAs were examined on apoptosis, with the aim to determine whether reversion of the drug‑resistance phenotype was obtained. Specificity of the PNA‑mediated effects was analyzed by reverse transcription‑quantitative polymerase‑chain reaction, which demonstrated that the effects of R8‑PNA‑a155 and R8-PNA-a221 anti‑miR PNAs were specific. Furthermore, the results obtained confirmed that both PNAs induced apoptosis when used on the temozolomide‑resistant T98G glioma cell line. Notably, co‑administration of both anti‑miR‑155 and anti‑miR‑221 PNAs was associated with an increased proapoptotic activity. In addition, TMZ further increased the induction of apoptosis in T98G cells co‑treated with anti‑miR‑155 and anti‑miR‑221 PNAs.
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Affiliation(s)
- Roberta Milani
- Department of Life Sciences and Biotechnology, University of Ferrara, I‑144121 Ferrara, Italy
| | - Eleonora Brognara
- Department of Life Sciences and Biotechnology, University of Ferrara, I‑144121 Ferrara, Italy
| | - Enrica Fabbri
- Department of Life Sciences and Biotechnology, University of Ferrara, I‑144121 Ferrara, Italy
| | - Alex Manicardi
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, I‑143214 Parma, Italy
| | - Roberto Corradini
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, I‑143214 Parma, Italy
| | - Alessia Finotti
- Department of Life Sciences and Biotechnology, University of Ferrara, I‑144121 Ferrara, Italy
| | - Jessica Gasparello
- Department of Life Sciences and Biotechnology, University of Ferrara, I‑144121 Ferrara, Italy
| | - Monica Borgatti
- Department of Life Sciences and Biotechnology, University of Ferrara, I‑144121 Ferrara, Italy
| | - Lucia Carmela Cosenza
- Department of Life Sciences and Biotechnology, University of Ferrara, I‑144121 Ferrara, Italy
| | - Ilaria Lampronti
- Department of Life Sciences and Biotechnology, University of Ferrara, I‑144121 Ferrara, Italy
| | | | - Giulio Cabrini
- Laboratory of Molecular Pathology, University‑Hospital of Verona, I‑37126 Verona, Italy
| | - Roberto Gambari
- Department of Life Sciences and Biotechnology, University of Ferrara, I‑144121 Ferrara, Italy
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22
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Manicardi A, Gambari R, de Cola L, Corradini R. Preparation of Anti-miR PNAs for Drug Development and Nanomedicine. Methods Mol Biol 2019; 1811:49-63. [PMID: 29926445 DOI: 10.1007/978-1-4939-8582-1_4] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Peptide Nucleic Acids (PNAs) are oligonucleotide mimics that can be used to block the biological action of microRNA, thus affecting gene expression post-transcriptionally. PNAs are obtained with solid-phase peptide synthesis, and can be easily conjugated to other peptides. Conjugation with R8-Peptide or modification of the PNA backbone (at C5 or C2 carbon) with arginine side chains allows efficient cellular uptake. The present protocol describes the synthesis of cationic PNAs that can be used alone as drugs or for efficient co-delivery in suitable inorganic nanocarriers.
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Affiliation(s)
- Alex Manicardi
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parma, Italy
| | - Roberto Gambari
- Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy
| | - Luisa de Cola
- Institut de Science et d'Ingénierie Supramoléculaires (ISIS) Université de Strasbourg, Strasbourg, France
| | - Roberto Corradini
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parma, Italy.
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23
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Efficient cell penetration and delivery of peptide nucleic acids by an argininocalix[4]arene. Sci Rep 2019; 9:3036. [PMID: 30816154 PMCID: PMC6395679 DOI: 10.1038/s41598-019-39211-4] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Accepted: 01/03/2019] [Indexed: 01/25/2023] Open
Abstract
The application of Peptide Nucleic Acids (PNAs), mimics of DNA lacking the sugar-phosphate backbone, for antisense/anti-gene therapy and gene editing is limited by their low uptake by cells. Currently, no simple and efficient delivery systems and methods are available to solve this open issue. One of the most promising approach is the modification of the PNA structure through the covalent linkage of poliarginine tails, but this means that every PNA intended to be internalized must be modified. Herein we report the results relative to the delivery ability of a macrocyclic multivalent tetraargininocalix[4]arene (1) used as non-covalent vector for anti-miR-221-3p PNAs. High delivery efficiency, low cytotoxicity, maintenance of the PNA biological activity and ease preparation of the transfection formulation, simply attained by mixing PNA and calixarene, candidate this vector as universal delivery system for this class of nucleic acid analogues.
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24
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Grijalvo S, Alagia A, Jorge AF, Eritja R. Covalent Strategies for Targeting Messenger and Non-Coding RNAs: An Updated Review on siRNA, miRNA and antimiR Conjugates. Genes (Basel) 2018; 9:E74. [PMID: 29415514 PMCID: PMC5852570 DOI: 10.3390/genes9020074] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Revised: 01/26/2018] [Accepted: 01/26/2018] [Indexed: 12/11/2022] Open
Abstract
Oligonucleotide-based therapy has become an alternative to classical approaches in the search of novel therapeutics involving gene-related diseases. Several mechanisms have been described in which demonstrate the pivotal role of oligonucleotide for modulating gene expression. Antisense oligonucleotides (ASOs) and more recently siRNAs and miRNAs have made important contributions either in reducing aberrant protein levels by sequence-specific targeting messenger RNAs (mRNAs) or restoring the anomalous levels of non-coding RNAs (ncRNAs) that are involved in a good number of diseases including cancer. In addition to formulation approaches which have contributed to accelerate the presence of ASOs, siRNAs and miRNAs in clinical trials; the covalent linkage between non-viral vectors and nucleic acids has also added value and opened new perspectives to the development of promising nucleic acid-based therapeutics. This review article is mainly focused on the strategies carried out for covalently modifying siRNA and miRNA molecules. Examples involving cell-penetrating peptides (CPPs), carbohydrates, polymers, lipids and aptamers are discussed for the synthesis of siRNA conjugates whereas in the case of miRNA-based drugs, this review article makes special emphasis in using antagomiRs, locked nucleic acids (LNAs), peptide nucleic acids (PNAs) as well as nanoparticles. The biomedical applications of siRNA and miRNA conjugates are also discussed.
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Affiliation(s)
- Santiago Grijalvo
- Institute of Advanced Chemistry of Catalonia (IQAC, CSIC), Jordi Girona 18-26, 08034 Barcelona, Spain.
- Networking Centre in Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Jordi Girona 18-26, 08034 Barcelona, Spain.
| | - Adele Alagia
- Networking Centre in Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Jordi Girona 18-26, 08034 Barcelona, Spain.
| | - Andreia F Jorge
- Coimbra Chemistry Centre, (CQC), Department of Chemistry, University of Coimbra, Rua Larga, 3004-535 Coimbra, Portugal.
| | - Ramon Eritja
- Institute of Advanced Chemistry of Catalonia (IQAC, CSIC), Jordi Girona 18-26, 08034 Barcelona, Spain.
- Networking Centre in Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Jordi Girona 18-26, 08034 Barcelona, Spain.
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25
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Elskens J, Manicardi A, Costi V, Madder A, Corradini R. Synthesis and Improved Cross-Linking Properties of C5-Modified Furan Bearing PNAs. Molecules 2017; 22:molecules22112010. [PMID: 29156637 PMCID: PMC6150320 DOI: 10.3390/molecules22112010] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2017] [Revised: 11/07/2017] [Accepted: 11/09/2017] [Indexed: 12/21/2022] Open
Abstract
Over the past decades, peptide nucleic acid/DNA (PNA:DNA) duplex stability has been improved via backbone modification, often achieved via introducing an amino acid side chain at the α- or γ-position in the PNA sequence. It was previously shown that interstrand cross-linking can further enhance the binding event. In this work, we combined both strategies to fine-tune PNA crosslinking towards single stranded DNA sequences using a furan oxidation-based crosslinking method; for this purpose, γ-l-lysine and γ-l-arginine furan-PNA monomers were synthesized and incorporated in PNA sequences via solid phase synthesis. It was shown that the l-lysine γ-modification had a beneficial effect on crosslink efficiency due to pre-organization of the PNA helix and a favorable electrostatic interaction between the positively-charged lysine and the negatively-charged DNA backbone. Moreover, the crosslink yield could be optimized by carefully choosing the type of furan PNA monomer. This work is the first to describe a selective and biocompatible furan crosslinking strategy for crosslinking of γ-modified PNA sequences towards single-stranded DNA.
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Affiliation(s)
- Joke Elskens
- Organic and Biomimetic Chemistry Research Group, Department of Organic and Macromolecular Chemistry, Ghent University, Krijgslaan 281-S4, 9000 Gent, Belgium.
| | - Alex Manicardi
- Organic and Biomimetic Chemistry Research Group, Department of Organic and Macromolecular Chemistry, Ghent University, Krijgslaan 281-S4, 9000 Gent, Belgium.
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 17/A, 43124 Parma, Italy.
| | - Valentina Costi
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 17/A, 43124 Parma, Italy.
| | - Annemieke Madder
- Organic and Biomimetic Chemistry Research Group, Department of Organic and Macromolecular Chemistry, Ghent University, Krijgslaan 281-S4, 9000 Gent, Belgium.
| | - Roberto Corradini
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parco Area delle Scienze 17/A, 43124 Parma, Italy.
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26
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Gupta A, Quijano E, Liu Y, Bahal R, Scanlon SE, Song E, Hsieh WC, Braddock DE, Ly DH, Saltzman WM, Glazer PM. Anti-tumor Activity of miniPEG-γ-Modified PNAs to Inhibit MicroRNA-210 for Cancer Therapy. MOLECULAR THERAPY-NUCLEIC ACIDS 2017; 9:111-119. [PMID: 29246289 PMCID: PMC5633812 DOI: 10.1016/j.omtn.2017.09.001] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/28/2017] [Revised: 09/05/2017] [Accepted: 09/06/2017] [Indexed: 11/30/2022]
Abstract
MicroRNAs (miRs) are frequently overexpressed in human cancers. In particular, miR-210 is induced in hypoxic cells and acts to orchestrate the adaptation of tumor cells to hypoxia. Silencing oncogenic miRs such as miR-210 may therefore offer a promising approach to anticancer therapy. We have developed a miR-210 inhibition strategy based on a new class of conformationally preorganized antisense γ peptide nucleic acids (γPNAs) that possess vastly superior RNA-binding affinity, improved solubility, and favorable biocompatibility. For cellular delivery, we encapsulated the γPNAs in poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs). Our results show that γPNAs targeting miR-210 cause significant delay in growth of a human tumor xenograft in mice compared to conventional PNAs. Further, histopathological analyses show considerable necrosis, fibrosis, and reduced cell proliferation in γPNA-treated tumors compared to controls. Overall, our work provides a chemical framework for a novel anti-miR therapeutic approach using γPNAs that should facilitate rational design of agents to potently inhibit oncogenic microRNAs.
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Affiliation(s)
- Anisha Gupta
- Department of Therapeutic Radiology, Yale University, New Haven, CT 06510, USA
| | - Elias Quijano
- Department of Biomedical Engineering, Yale University, New Haven, CT 06520, USA
| | - Yanfeng Liu
- Department of Therapeutic Radiology, Yale University, New Haven, CT 06510, USA
| | - Raman Bahal
- Department of Pharmaceutical Sciences, University of Connecticut, Storrs, CT 06269, USA
| | - Susan E Scanlon
- Department of Therapeutic Radiology, Yale University, New Haven, CT 06510, USA
| | - Eric Song
- Department of Biomedical Engineering, Yale University, New Haven, CT 06520, USA
| | - Wei-Che Hsieh
- Department of Chemistry and Center for Nucleic Acids Science and Technology (CNAST), Carnegie Mellon University, Pittsburgh, PA 15213, USA
| | | | - Danith H Ly
- Department of Chemistry and Center for Nucleic Acids Science and Technology (CNAST), Carnegie Mellon University, Pittsburgh, PA 15213, USA
| | - W Mark Saltzman
- Department of Biomedical Engineering, Yale University, New Haven, CT 06520, USA
| | - Peter M Glazer
- Department of Therapeutic Radiology, Yale University, New Haven, CT 06510, USA; Department of Genetics, Yale University, New Haven, CT 06510, USA.
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27
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Manicardi A, Rozzi A, Korom S, Corradini R. Building on the peptide nucleic acid (PNA) scaffold: a biomolecular engineering approach. Supramol Chem 2017. [DOI: 10.1080/10610278.2017.1371720] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Alex Manicardi
- Dipartimento di Scienze Chimiche, della Vita e della Sostenibilità Ambientale, Università di Parma, Parma, Italy
- Organic and Biomimetic Chemistry Research Group (OBCR), Department of Organic and Macromolecular Chemistry, Faculty of Sciences – Ghent University Campus Sterre, Belgium
| | - Andrea Rozzi
- Dipartimento di Scienze Chimiche, della Vita e della Sostenibilità Ambientale, Università di Parma, Parma, Italy
| | - Saša Korom
- National Institute for Biostructures and Biosystems (INBB), Roma, Italy
| | - Roberto Corradini
- Dipartimento di Scienze Chimiche, della Vita e della Sostenibilità Ambientale, Università di Parma, Parma, Italy
- National Institute for Biostructures and Biosystems (INBB), Roma, Italy
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Kamiya Y, Donoshita Y, Kamimoto H, Murayama K, Ariyoshi J, Asanuma H. Introduction of 2,6-Diaminopurines into Serinol Nucleic Acid Improves Anti-miRNA Performance. Chembiochem 2017; 18:1917-1922. [PMID: 28748559 DOI: 10.1002/cbic.201700272] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Indexed: 12/14/2022]
Abstract
MicroRNAs (miRNAs) are endogenous small RNAs that regulate gene expression at the post-transcriptional level by sequence-specific hybridisation. Anti-miRNA oligonucleotides (AMOs) are inhibitors of miRNA activity. Chemical modification of AMOs is required to increase binding affinity and stability in serum and cells. In this study, we synthesised AMOs with our original acyclic nucleic acid, serinol nucleic acid (SNA), backbone and with the artificial nucleobase 2,6-diaminopurine. The AMO composed of only SNA had strong nuclease resistance and blocked endogenous miRNA activity. A significant improvement in anti-miRNA activity of the AMO was achieved by introduction of a 2,6-diaminopurine residues into the SNA backbone. In addition, we found that the enhancement in AMO activity depended on the position of the 2,6-diaminopurine residue in the sequence. The high potency of the SNA-AMOs suggests that these oligomers will be useful as therapeutic reagents for control of miRNA function in patients and as tools for investigating the roles of microRNAs in cells.
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Affiliation(s)
- Yukiko Kamiya
- Department of Biomolecular Engineering, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8603, Japan
| | - Yuka Donoshita
- Department of Biomolecular Engineering, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8603, Japan
| | - Hiroshi Kamimoto
- Department of Biomolecular Engineering, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8603, Japan
| | - Keiji Murayama
- Department of Biomolecular Engineering, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8603, Japan
| | - Jumpei Ariyoshi
- Department of Biomolecular Engineering, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8603, Japan.,Venture Business Laboratory (VBL), Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8603, Japan
| | - Hiroyuki Asanuma
- Department of Biomolecular Engineering, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8603, Japan
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Tähtinen V, Granqvist L, Murtola M, Strömberg R, Virta P. 19 F NMR Spectroscopic Analysis of the Binding Modes in Triple-Helical Peptide Nucleic Acid (PNA)/MicroRNA Complexes. Chemistry 2017; 23:7113-7124. [PMID: 28370485 DOI: 10.1002/chem.201700601] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Indexed: 12/21/2022]
Abstract
Triplex-forming peptide nucleic acids (TFPNAs) were targeted to double-helical regions of 19 F-labeled RNA hairpin models (a UA-rich duplex with a hexaethylene glycol (heg) loop and a microRNA model, miR-215). In addition to conventional UV- and circular dichroism (CD)-based detection, binding was monitored by 19 F NMR spectroscopy. Detailed information on the stoichiometry and transition between the triple-helical peptide nucleic acid (PNA)/RNA and (PNA)2 /RNA binding modes could be obtained. γ-(R)-Hydroxymethyl-modified thymine-1-yl- and 2-aminopyridin-3-yl-acetyl derivatives of TFPNAs were additionally synthesized, which were targeted to the same RNA models, and the effect of the γ-(R)-hydroxymethyl group on binding was studied. An appropriate pattern of γ-(R)-hydroxymethyl modifications reduced the stability of the ternary complex and preferred stoichiometric binding to the miR-215 model.
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Affiliation(s)
- Ville Tähtinen
- Department of Chemistry, University of Turku, Turku, 20014, Finland
| | - Lotta Granqvist
- Department of Chemistry, University of Turku, Turku, 20014, Finland
| | - Merita Murtola
- Department of Chemistry, University of Turku, Turku, 20014, Finland.,Department of Biosciences and Nutrition, Karolinska Institutet, Novum, 141 83, Huddinge, Stockholm, Sweden
| | - Roger Strömberg
- Department of Biosciences and Nutrition, Karolinska Institutet, Novum, 141 83, Huddinge, Stockholm, Sweden
| | - Pasi Virta
- Department of Chemistry, University of Turku, Turku, 20014, Finland
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Verona MD, Verdolino V, Palazzesi F, Corradini R. Focus on PNA Flexibility and RNA Binding using Molecular Dynamics and Metadynamics. Sci Rep 2017; 7:42799. [PMID: 28211525 PMCID: PMC5314342 DOI: 10.1038/srep42799] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Accepted: 01/13/2017] [Indexed: 12/20/2022] Open
Abstract
Peptide Nucleic Acids (PNAs) can efficiently target DNA or RNA acting as chemical tools for gene regulation. Their backbone modification and functionalization is often used to increase the affinity for a particular sequence improving selectivity. The understanding of the trading forces that lead the single strand PNA to bind the DNA or RNA sequence is preparatory for any further rational design, but a clear and unique description of this process is still not complete. In this paper we report further insights into this subject, by a computational investigation aiming at the characterization of the conformations of a single strand PNA and how these can be correlated to its capability in binding DNA/RNA. Employing Metadynamics we were able to better define conformational pre-organizations of the single strand PNA and γ-modified PNA otherwise unrevealed through classical molecular dynamics. Our simulations driven on backbone modified PNAs lead to the conclusion that this γ-functionalization affects the single strand preorganization and targeting properties to the DNA/RNA, in agreement with circular dichroism (CD) spectra obtained for this class of compounds. MD simulations on PNA:RNA dissociation and association mechanisms allowed to reveal the critical role of central bases and preorganization in the binding process.
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Affiliation(s)
| | - Vincenzo Verdolino
- Department of Chemistry and Applied Biosciences, ETH Zurich, c/o Università della Svizzera Italiana Campus, 6900 Lugano, Switzerland
- Facoltà di Informatica, Instituto di Scienze Computazionali, Università della Svizzera Italiana, 6900 Lugano, Switzerland
| | - Ferruccio Palazzesi
- Department of Chemistry and Applied Biosciences, ETH Zurich, c/o Università della Svizzera Italiana Campus, 6900 Lugano, Switzerland
- Facoltà di Informatica, Instituto di Scienze Computazionali, Università della Svizzera Italiana, 6900 Lugano, Switzerland
| | - Roberto Corradini
- Dipartimento di Chimica, University of Parma, Italy, 43124, Italy
- National Institute for Biostructures and Biosystems (INBB)-Viale delle Medaglie d’Oro, 305, 00136 Roma, Italy
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Sharma S, Mathew AB, Chugh J. miRNAs: Nanomachines That Micromanage the Pathophysiology of Diabetes Mellitus. Adv Clin Chem 2017; 82:199-264. [PMID: 28939211 DOI: 10.1016/bs.acc.2017.06.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Diabetes mellitus (DM) refers to a combination of heterogeneous complex metabolic disorders that are associated with episodes of hyperglycemia and glucose intolerance occurring as a result of defects in insulin secretion, action, or both. The prevalence of DM is increasing at an alarming rate, and there exists a need to develop better therapeutics and prognostic markers for earlier detection and diagnosis. In this review, after giving a brief introduction of diabetes mellitus and microRNA (miRNA) biogenesis pathway, we first describe various in vitro and animal model systems that have been developed to study diabetes. Further, we elaborate on the significant roles played by miRNAs as regulators of gene expression in the context of development of diabetes and its secondary complications. The different approaches to quantify miRNAs and their potential to be used as therapeutic targets for alleviation of diabetes have also been discussed.
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Patil KM, Chen G. Recognition of RNA Sequence and Structure by Duplex and Triplex Formation: Targeting miRNA and Pre-miRNA. ACTA ACUST UNITED AC 2016. [DOI: 10.1007/978-3-319-34175-0_13] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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Ghidini A, Bergquist H, Murtola M, Punga T, Zain R, Strömberg R. Clamping of RNA with PNA enables targeting of microRNA. Org Biomol Chem 2016; 14:5210-3. [PMID: 27203783 DOI: 10.1039/c6ob00516k] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
To be able to target microRNAs also at stages where these are in a double stranded or hairpin form we have studied BisPNA designed to clamp the target and give sufficient affinity to allow for strand invasion. We show that BisPNA complexes are more stable with RNA than with DNA. In addition, 24-mer BisPNA (AntimiR) constructs form complexes with a hairpin RNA that is a model of the microRNA miR-376b, suggesting that PNA-clamping may be an effective way of targeting microRNAs.
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Affiliation(s)
- Alice Ghidini
- Department of Biosciences and Nutrition, Karolinska Institutet, Novum, 141 83 Huddinge, Stockholm, Sweden.
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Brognara E, Fabbri E, Montagner G, Gasparello J, Manicardi A, Corradini R, Bianchi N, Finotti A, Breveglieri G, Borgatti M, Lampronti I, Milani R, Dechecchi MC, Cabrini G, Gambari R. High levels of apoptosis are induced in human glioma cell lines by co-administration of peptide nucleic acids targeting miR-221 and miR-222. Int J Oncol 2015; 48:1029-38. [PMID: 26708164 DOI: 10.3892/ijo.2015.3308] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Accepted: 09/04/2015] [Indexed: 11/06/2022] Open
Abstract
The biological activity of a combined treatment of U251, U373 and T98G glioma cell lines with two anti-miR PNAs, directed against miR‑221 and miR‑222 and conjugated with an ocataarginine tail (R8-PNA-a221 and R8-PNA-a222) for efficient cellular delivery, was determined. Apoptosis was analyzed, and the effect of the combined treatment of glioma cells with either or both PNAs on the reversion of drug-resistance phenotype was assessed in the temozolomide-resistant T98G glioma cell line. Selectivity of PNA/miRNA interactions was studied by surface plasmon resonance (SPR)-based Biacore analysis. Specificity of the PNA effects at the cellular level was analyzed by RT-qPCR. These experiments support the concept that the effects of R8-PNA-a221 and R8-PNA-a222 are specific. The studies on apoptosis confirmed that the R8-PNA-a221 induces apoptosis and demonstrated the pro-apoptotic effects of R8-PNA-a222. Remarkably, increased pro-apoptotic effects were obtained with the co-administration of both anti-miR‑221 and anti-miR‑222 PNAs. In addition, co-administration of R8-PNA-a221 and R8-PNA-a222 induced apoptosis of TMZ-treated T98G cells at a level higher than that obtained following singular administration of R8-PNA-a221 or R8-PNA-a222.
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Affiliation(s)
- Eleonora Brognara
- Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy
| | - Enrica Fabbri
- Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy
| | - Giulia Montagner
- Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy
| | - Jessica Gasparello
- Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy
| | - Alex Manicardi
- Department of Chemistry, University of Parma, Parma, Italy
| | | | - Nicoletta Bianchi
- Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy
| | - Alessia Finotti
- Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy
| | - Giulia Breveglieri
- Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy
| | - Monica Borgatti
- Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy
| | - Ilaria Lampronti
- Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy
| | - Roberta Milani
- Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy
| | | | - Giulio Cabrini
- Laboratory of Molecular Pathology, University-Hospital of Verona, Verona, Italy
| | - Roberto Gambari
- Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy
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Avitabile C, Accardo A, Ringhieri P, Morelli G, Saviano M, Montagner G, Fabbri E, Gallerani E, Gambari R, Romanelli A. Incorporation of Naked Peptide Nucleic Acids into Liposomes Leads to Fast and Efficient Delivery. Bioconjug Chem 2015; 26:1533-41. [PMID: 26176882 DOI: 10.1021/acs.bioconjchem.5b00156] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The delivery of peptide nucleic acids (PNAs) to cells is a very challenging task. We report here that a liposomal formulation composed of egg PC/cholesterol/DSPE-PEG2000 can be loaded, according to different encapsulation techniques, with PNA or fluorescent PNA oligomers. PNA loaded liposomes efficiently and quickly promote the uptake of a PNA targeting the microRNA miR-210 in human erythroleukemic K562 cells. By using this innovative delivery system for PNA, down-regulation of miR-210 is achieved at a low PNA concentration.
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Affiliation(s)
- Concetta Avitabile
- †Institute of Biostructure and Bioimaging (IBB), CNR, via Mezzocannone 16, 80134 Napoli, Italy
| | - Antonella Accardo
- ‡Department of Pharmacy, University of Naples "Federico II", via Mezzocannone 16, 80134 Napoli, Italy.,§Interuniversity Research Centre on Bioactive Peptides (CIRPeB), via Mezzocannone 16, 80134 Napoli, Italy
| | - Paola Ringhieri
- ‡Department of Pharmacy, University of Naples "Federico II", via Mezzocannone 16, 80134 Napoli, Italy
| | - Giancarlo Morelli
- ‡Department of Pharmacy, University of Naples "Federico II", via Mezzocannone 16, 80134 Napoli, Italy.,§Interuniversity Research Centre on Bioactive Peptides (CIRPeB), via Mezzocannone 16, 80134 Napoli, Italy
| | - Michele Saviano
- §Interuniversity Research Centre on Bioactive Peptides (CIRPeB), via Mezzocannone 16, 80134 Napoli, Italy.,∥Institute of Crystallography (IC), CNR, Via Amendola 122, 70126 Bari, Italy
| | - Giulia Montagner
- ⊥Department of Life Sciences and Biotechnologies, University of Ferrara, via Fossato di Mortara 74, 44121 Ferrara, Italy
| | - Enrica Fabbri
- ⊥Department of Life Sciences and Biotechnologies, University of Ferrara, via Fossato di Mortara 74, 44121 Ferrara, Italy
| | - Eleonora Gallerani
- ⊥Department of Life Sciences and Biotechnologies, University of Ferrara, via Fossato di Mortara 74, 44121 Ferrara, Italy
| | - Roberto Gambari
- ⊥Department of Life Sciences and Biotechnologies, University of Ferrara, via Fossato di Mortara 74, 44121 Ferrara, Italy
| | - Alessandra Romanelli
- ‡Department of Pharmacy, University of Naples "Federico II", via Mezzocannone 16, 80134 Napoli, Italy.,§Interuniversity Research Centre on Bioactive Peptides (CIRPeB), via Mezzocannone 16, 80134 Napoli, Italy
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36
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Moccia M, Adamo MFA, Saviano M. Insights on chiral, backbone modified peptide nucleic acids: Properties and biological activity. ARTIFICIAL DNA, PNA & XNA 2014; 5:e1107176. [PMID: 26752710 PMCID: PMC5329900 DOI: 10.1080/1949095x.2015.1107176] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2015] [Revised: 10/02/2015] [Accepted: 10/07/2015] [Indexed: 12/14/2022]
Abstract
PNAs are emerging as useful synthetic devices targeting natural miRNAs. In particular 3 classes of structurally modified PNAs analogs are herein described, namely α, β and γ, which differ by their backbone modification. Their mode and binding affinity for natural nucleic acids and their use in medicinal chemistry as potential miRNA binders is discussed.
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Affiliation(s)
- Maria Moccia
- Consiglio Nazionale delle Ricerche-Institute of Cristallography; Bari, Italy
| | - Mauro F A Adamo
- Centre for Synthesis and Chemical Biology (CSCB); Department of Pharmaceutical & Medicinal Chemistry; Royal College of Surgeons in Ireland; Dublin, Ireland
| | - Michele Saviano
- Consiglio Nazionale delle Ricerche-Institute of Cristallography; Bari, Italy
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37
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Manicardi A, Corradini R. Effect of chirality in gamma-PNA: PNA interaction, another piece in the picture. ARTIFICIAL DNA, PNA & XNA 2014; 5:e1131801. [PMID: 26744081 PMCID: PMC5329894 DOI: 10.1080/1949095x.2015.1131801] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2015] [Revised: 12/09/2015] [Accepted: 12/10/2015] [Indexed: 12/23/2022]
Abstract
Modification of the PNA backbone can be used to broaden their utility by introducing new functional groups. In particular, gamma-modified PNA have been found to be quite effective in a number of applications, and exhibit particularly high DNA binding affinity. The introduction of one side chain imply that the achiral backbone of PNA becomes chiral, and binding properties depend on the stereochemistry. A new paper on gamma-modified PNA by Ly and co-workers complete the existing knowledge by displaying that in binding to complementary PNA stereochemical orthogonality can be demonstrated. This opens the way to the exploitation of stereochemical features in diagnostic assays and in nanofabrication.
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Affiliation(s)
- Alex Manicardi
- Dipartimento di Chimica; University of Parma; Parma, Italy
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Bertucci A, Lülf H, Septiadi D, Manicardi A, Corradini R, De Cola L. Intracellular delivery of peptide nucleic acid and organic molecules using zeolite-L nanocrystals. Adv Healthc Mater 2014; 3:1812-7. [PMID: 24789252 DOI: 10.1002/adhm.201400116] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2014] [Revised: 03/19/2014] [Indexed: 12/12/2022]
Abstract
The design and synthesis of smart nanomaterials can provide interesting potential applications for biomedical purposes from bioimaging to drug delivery. Manufacturing multifunctional systems in a way to carry bioactive molecules, like peptide nucleic acids able to recognize specific targets in living cells, represents an achievement towards the development of highly selective tools for both diagnosis and therapeutics. This work describes a very first example of the use of zeolite nanocrystals as multifunctional nanocarriers to deliver simultaneously PNA and organic molecules into living cells. Zeolite-L nanocrystals are functionalized by covalently attaching the PNA probes onto the surface, while the channel system is filled with fluorescent guest molecules. The cellular uptake of the PNA/Zeolite-L hybrid material is then significantly increased by coating the whole system with a thin layer of biodegradable poly-L-lysine. The delivery of DAPI as a model drug molecule, inserted into the zeolite pores, is also demonstrated to occur in the cells, proving the multifunctional ability of the system. Using this zeolite nanosystem carrying PNA probes designed to target specific RNA sequences of interest in living cells could open new possibilities for theranostic and gene therapy applications.
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Affiliation(s)
- Alessandro Bertucci
- Institut de science et d'ingénierie supramoléculaire (ISIS), icFRC and CNRS; Université de Strasbourg; 8 Rue Gaspard Monge, BP 70028 67000 Strasbourg France
- Dipartimento di Chimica; Università di Parma; Parco Area delle Scienze, 17/A 43124 Parma Italy
| | - Henning Lülf
- Dipartimento di Chimica; Università di Parma; Parco Area delle Scienze, 17/A 43124 Parma Italy
| | - Dedy Septiadi
- Institut de science et d'ingénierie supramoléculaire (ISIS), icFRC and CNRS; Université de Strasbourg; 8 Rue Gaspard Monge, BP 70028 67000 Strasbourg France
| | - Alex Manicardi
- Dipartimento di Chimica; Università di Parma; Parco Area delle Scienze, 17/A 43124 Parma Italy
| | - Roberto Corradini
- Dipartimento di Chimica; Università di Parma; Parco Area delle Scienze, 17/A 43124 Parma Italy
| | - Luisa De Cola
- Institut de science et d'ingénierie supramoléculaire (ISIS), icFRC and CNRS; Université de Strasbourg; 8 Rue Gaspard Monge, BP 70028 67000 Strasbourg France
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Second generation, arginine-rich (R–X′–R)4-type cell-penetrating α–ω–α-peptides with constrained, chiral ω-amino acids (X′) for enhanced cargo delivery into cells. Bioorg Med Chem Lett 2014; 24:4198-202. [DOI: 10.1016/j.bmcl.2014.07.040] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Revised: 07/02/2014] [Accepted: 07/15/2014] [Indexed: 11/23/2022]
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Brognara E, Fabbri E, Bianchi N, Finotti A, Corradini R, Gambari R. Molecular methods for validation of the biological activity of peptide nucleic acids targeting microRNAs. Methods Mol Biol 2014; 1095:165-76. [PMID: 24166312 DOI: 10.1007/978-1-62703-703-7_14] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The involvement of microRNAs in human pathologies is a firmly established fact. Accordingly, the pharmacological modulation of their activity appears to be a very appealing issue in the development of new types of drugs (miRNA therapeutics). One of the most interesting issues is the possible development of miRNA therapeutics for development of anti-cancer molecules. In this respect appealing molecules are based on peptide nucleic acids (PNAs), displaying a pseudo-peptide backbone composed of N-(2-aminoethyl)glycine units and found to be excellent candidates for antisense and antigene therapies. The major limit in the use of PNAs for alteration of gene expression is the low uptake by eukaryotic cells. The aim of this chapter is to describe methods for determining the activity of PNAs designed to target oncomiRNAs, using as model system miR-221 and its target p27(Kip1) mRNA. The effects of PNAs targeting miR-221 are here presented discussing data obtained using as model system the human breast cancer cell line MDA-MB-231, in which miR-221 is up-regulated and p27(Kip1) down-regulated.
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Affiliation(s)
- Eleonora Brognara
- Department of Life Sciences and Biotechnology, Ferrara University, Ferrara, Italy
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Exploitation of a very small peptide nucleic acid as a new inhibitor of miR-509-3p involved in the regulation of cystic fibrosis disease-gene expression. BIOMED RESEARCH INTERNATIONAL 2014; 2014:610718. [PMID: 24829907 PMCID: PMC4009323 DOI: 10.1155/2014/610718] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/06/2013] [Accepted: 03/18/2014] [Indexed: 12/13/2022]
Abstract
Computational techniques, and in particular molecular dynamics (MD) simulations, have been successfully used as a complementary technique to predict and analyse the structural behaviour of nucleic acids, including peptide nucleic acid- (PNA-) RNA hybrids. This study shows that a 7-base long PNA complementary to the seed region of miR-509-3p, one of the miRNAs involved in the posttranscriptional regulation of the CFTR disease-gene of Cystic Fibrosis, and bearing suitable functionalization at its N- and C-ends aimed at improving its resistance to nucleases and cellular uptake, is able to revert the expression of the luciferase gene containing the 3′UTR of the gene in A549 human lung cancer cells, in agreement with the MD results that pointed at the formation of a stable RNA/PNA heteroduplex notwithstanding the short sequence of the latter. The here reported results widen the interest towards the use of small PNAs as effective anti-miRNA agents.
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42
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Uptake by human glioma cell lines and biological effects of a peptide-nucleic acids targeting miR-221. J Neurooncol 2014; 118:19-28. [PMID: 24595467 DOI: 10.1007/s11060-014-1405-6] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2013] [Accepted: 02/17/2014] [Indexed: 10/25/2022]
Abstract
MicroRNAs are a family of small noncoding RNAs regulating gene expression by sequence-selective mRNA targeting, leading to a translational repression or mRNA degradation. The oncomiR miR-221 is highly expressed in human gliomas, as confirmed in this study in samples of low and high grade gliomas, as well in the cell lines U251, U373 and T98G. In order to alter the biological functions of miR-221, a peptide nucleic acid targeting miR-221 (R8-PNA-a221) was produced, bearing a oligoarginine peptide (R8) to facilitate uptake by glioma cells. The effects of R8-PNA-a221 were analyzed in U251, U373 and T98G glioma cells and found to strongly inhibit miR-221. In addition, the effects of R8-PNA-a221 on p27(Kip1) (a target of miR-221) were analyzed in U251 and T98G cells by RT-qPCR and by Western blotting. No change of p27(Kip1) mRNA content occurs in U251 cells in the presence of PNA-a221 (lacking the R8 peptide), whereas significant increase of p27(Kip1) mRNA was observed with the R8-PNA-a221. These data were confirmed by Western blot assay. A clear increment of p27(Kip1) protein expression in the samples treated with R8-PNA-a221 was detected. In addition, R8-PNA-a221 was found able to increase TIMP3 expression (another target of miR-221) in T98G cells. These results suggest that PNAs against oncomiRNA miR-221 might be proposed for experimental treatment of human gliomas.
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Gambari R. Peptide nucleic acids: a review on recent patents and technology transfer. Expert Opin Ther Pat 2014; 24:267-94. [PMID: 24405414 DOI: 10.1517/13543776.2014.863874] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
INTRODUCTION DNA/RNA-based drugs are considered of major interest in molecular diagnosis and nonviral gene therapy. In this field, peptide nucleic acids (PNAs, DNA analogs in which the sugar-phosphate backbone is replaced by N-(2-aminoethyl)glycine units or similar building blocks) have been demonstrated to be excellent candidates as diagnostic reagents and biodrugs. AREAS COVERED Recent (2002 - 2013) patents based on studies on development of PNA analogs, delivery systems for PNAs, applications of PNAs in molecular diagnosis, and use of PNA for innovative therapeutic protocols. EXPERT OPINION PNAs are unique reagents in molecular diagnosis and have been proven to be very active and specific for alteration of gene expression, despite the fact that solubility and uptake by target cells can be limiting factors. Accordingly, patents on PNAs have taken in great consideration delivery strategies. PNAs have been proven stable and effective in vivo, despite the fact that possible long-term toxicity should be considered. For possible clinical applications, the use of PNA molecules in combination with drugs already employed in therapy has been suggested. Considering the patents available and the results on in vivo testing on animal models, we expect in the near future relevant PNA-based clinical trials.
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Affiliation(s)
- Roberto Gambari
- University of Ferrara, Department of Life Sciences and Biotechnology, Biochemistry and Molecular Biology Section , Via Fossato di Mortara n.74, 44100 Ferrara , Italy +39 532 974443 ; +39 532 974500 ;
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Amato F, Tomaiuolo R, Borbone N, Elce A, Amato J, D'Errico S, De Rosa G, Mayol L, Piccialli G, Oliviero G, Castaldo G. Design, synthesis and biochemical investigation, by in vitro luciferase reporter system, of peptide nucleic acids as new inhibitors of miR-509-3p involved in the regulation of cystic fibrosis disease-gene expression. MEDCHEMCOMM 2014. [DOI: 10.1039/c3md00257h] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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Piva R, Spandidos DA, Gambari R. From microRNA functions to microRNA therapeutics: novel targets and novel drugs in breast cancer research and treatment (Review). Int J Oncol 2013; 43:985-94. [PMID: 23939688 PMCID: PMC3829774 DOI: 10.3892/ijo.2013.2059] [Citation(s) in RCA: 99] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2013] [Accepted: 08/12/2013] [Indexed: 12/12/2022] Open
Abstract
MicroRNAs (miRNAs or miRs) are a family of small non-coding RNAs that regulate gene expression by the sequence-selective targeting of mRNAs, leading to translational repression or mRNA degradation, depending on the degree of complementarity with target mRNA sequences. miRNAs play a crucial role in cancer. In the case of breast tumors, several studies have demonstrated a correlation between: i) the expression profile of oncogenic miRNAs (oncomiRs) or tumor suppressor miRNAs and ii) the tumorigenic potential of triple-negative [estrogen receptor (ER), progesterone receptor (PR) and Her2/neu] primary breast cancers. Among the miRNAs involved in breast cancer, miR-221 plays a crucial role for the following reasons: i) miR-221 is significantly overexpressed in triple-negative primary breast cancers; ii) the oncosuppressor p27
Kip1
, a validated miR-221 target, is downregulated in aggressive cancer cell lines; and iii) the upregulation of a key transcription factor, Slug, appears to be crucial, since it binds to the miR-221/miR-222 promoter and is responsible for the high expression of the miR-221/miR-222 cluster in breast cancer cells. A Slug/miR-221 network has been suggested, linking miR-221 activity with the downregulation of a Slug repressor, leading to Slug/miR-221 upregulation and p27
Kip1
downregulation. Interference with this process can be achieved using antisense miRNA (antagomiR) molecules targeting miR-221, inducing the down-regulation of Slug and the upregulation of p27
Kip1
.
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Affiliation(s)
- Roberta Piva
- Department of Biomedical and Specialty Surgical Sciences, Ferrara University, Ferrara, Italy
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Sugiyama T, Kittaka A. Chiral peptide nucleic acids with a substituent in the N-(2-aminoethy)glycine backbone. Molecules 2012; 18:287-310. [PMID: 23271467 PMCID: PMC6269907 DOI: 10.3390/molecules18010287] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2012] [Revised: 12/19/2012] [Accepted: 12/19/2012] [Indexed: 11/16/2022] Open
Abstract
A peptide nucleic acid (PNA) is a synthetic nucleic acid mimic in which the sugar-phosphate backbone is replaced by a peptide backbone. PNAs hybridize to complementary DNA and RNA with higher affinity and superior sequence selectivity compared to DNA. PNAs are resistant to nucleases and proteases and have a low affinity for proteins. These properties make PNAs an attractive agent for biological and medical applications. To improve the antisense and antigene properties of PNAs, many backbone modifications of PNAs have been explored under the concept of preorganization. This review focuses on chiral PNAs bearing a substituent in the N-(2-aminoethyl)glycine backbone. Syntheses, properties, and applications of chiral PNAs are described.
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Affiliation(s)
- Toru Sugiyama
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902, Japan
- Author to whom correspondence should be addressed; E-Mail: ; Tel./Fax: +81-3-5465-8743
| | - Atsushi Kittaka
- Faculty of Pharmaceutical Sciences, Teikyo University, Kaga, Itabashi-ku, Tokyo 173-8605, Japan; E-Mail:
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Hong L, Han Y, Zhang H, Zhao Q, Qiao Y. miR-210: a therapeutic target in cancer. Expert Opin Ther Targets 2012; 17:21-8. [DOI: 10.1517/14728222.2012.732066] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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Recent advances in chemical modification of Peptide nucleic acids. J Nucleic Acids 2012; 2012:518162. [PMID: 22991652 PMCID: PMC3443988 DOI: 10.1155/2012/518162] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2012] [Revised: 07/12/2012] [Accepted: 07/20/2012] [Indexed: 12/14/2022] Open
Abstract
Peptide nucleic acid (PNA) has become an extremely powerful tool in chemistry and biology. Although PNA recognizes single-stranded nucleic acids with exceptionally high affinity and sequence selectivity, there is considerable ongoing effort to further improve properties of PNA for both fundamental science and practical applications. The present paper discusses selected recent studies that improve on cellular uptake and binding of PNA to double-stranded DNA and RNA. The focus is on chemical modifications of PNA's backbone and heterocyclic nucleobases. The paper selects representative recent studies and does not attempt to provide comprehensive coverage of the broad and vibrant field of PNA modification.
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