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1.
Int J Mol Sci ; 24(8)2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-37108234

RESUMO

Therapeutic oligonucleotides are powerful tools for the inhibition of potential targets involved in cancer. We describe the effect of two Polypurine Reverse Hoogsteen (PPRH) hairpins directed against the ERBB2 gene, which is overexpressed in positive HER-2 breast tumors. The inhibition of their target was analyzed by cell viability and at the mRNA and protein levels. The combination of these specific PPRHs with trastuzumab was also explored in breast cancer cell lines, both in vitro and in vivo. PPRHs designed against two intronic sequences of the ERBB2 gene decreased the viability of SKBR-3 and MDA-MB-453 breast cancer cells. The decrease in cell viability was associated with a reduction in ERBB2 mRNA and protein levels. In combination with trastuzumab, PPRHs showed a synergic effect in vitro and reduced tumor growth in vivo. These results represent the preclinical proof of concept of PPRHs as a therapeutic tool for breast cancer.


Assuntos
Neoplasias da Mama , Genes erbB-2 , Humanos , Feminino , Trastuzumab/farmacologia , Trastuzumab/genética , Oncogenes , Células MCF-7 , RNA Mensageiro/genética , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Receptor ErbB-2/genética
2.
J Org Chem ; 87(22): 15693-15702, 2022 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-36329560

RESUMO

A Diels-Alder reaction leading to 4-nitrophenylcyclohexanones followed by a newly developed base-mediated reductive cyclization of the resulting ketone tethered to the nitrobenzene moiety gives access to the hexahydro-2,6-methano-1-benzazocine ring system present in several biologically interesting natural products such as aspernomine. The scope of the reaction was explored with eight substituted nitrobenzenes, obtaining yields of up to 87%. The highest cytotoxicity was observed in benzazocine 4h, bearing an enone moiety, which was active against eight cancer cell lines.


Assuntos
Compostos Heterocíclicos , Ciclização , Cetonas
3.
Int J Mol Sci ; 23(4)2022 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-35216221

RESUMO

KRAS is a GTPase involved in the proliferation signaling of several growth factors. The KRAS gene is GC-rich, containing regions with known and putative G-quadruplex (G4) forming regions. Within the middle of the G-rich proximal promoter, stabilization of the physiologically active G4mid structure downregulates transcription of KRAS; the function and formation of other G4s within the gene are unknown. Herein we identify three putative G4-forming sequences (G4FS) within the KRAS gene, explore their G4 formation, and develop oligonucleotides targeting these three regions and the G4mid forming sequence. We tested Polypurine Reverse Hoogsteen hairpins (PPRHs) for their effects on KRAS regulation via enhancing G4 formation or displacing G-rich DNA strands, downregulating KRAS transcription and mediating an anti-proliferative effect. Five PPRH were designed, two against the KRAS promoter G4mid and three others against putative G4FS in the distal promoter, intron 1 and exon 5. PPRH binding was confirmed by gel electrophoresis. The effect on KRAS transcription was examined by luciferase, FRET Melt2, qRT-PCR. Cytotoxicity was evaluated in pancreatic and ovarian cancer cells. PPRHs decreased activity of a luciferase construct driven by the KRAS promoter. PPRH selectively suppressed proliferation in KRAS dependent cancer cells. PPRH demonstrated synergistic activity with a KRAS promoter selective G4-stabilizing compound, NSC 317605, in KRAS-dependent pancreatic cells. PPRHs selectively stabilize G4 formation within the KRAS mid promoter region and represent an innovative approach to both G4-stabilization and to KRAS modulation with potential for development into novel therapeutics.


Assuntos
Oligonucleotídeos/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Purinas/metabolismo , Sequência de Bases , Linhagem Celular , DNA/genética , Éxons/genética , Células HEK293 , Humanos , Íntrons/genética , Regiões Promotoras Genéticas/genética , Transcrição Gênica/genética
4.
Int J Mol Sci ; 24(1)2022 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-36613820

RESUMO

The oncogene MYC has key roles in transcription, proliferation, deregulating cellular energetics, and more. Modulating the expression or function of the MYC protein is a viable therapeutic goal in an array of cancer types, and potential inhibitors of MYC with high specificity and selectivity are of great interest. In cancer cells addicted to their aberrant MYC function, suppression can lead to apoptosis, with minimal effects on non-addicted, non-oncogenic cells, providing a wide therapeutic window for specific and efficacious anti-tumor treatment. Within the promoter of MYC lies a GC-rich, G-quadruplex (G4)-forming region, wherein G4 formation is capable of mediating transcriptional downregulation of MYC. Such GC-rich regions of DNA are prime targets for regulation with Polypurine Reverse Hoogsteen hairpins (PPRHs). The current study designed and examined PPRHs targeting the G4-forming and four other GC-rich regions of DNA within the promoter or intronic regions. Six total PPRHs were designed, examined in cell-free conditions for target engagement and in cells for transcriptional modulation, and correlating cytotoxic activity in pancreatic, prostate, neuroblastoma, colorectal, ovarian, and breast cancer cells. Two lead PPRHs, one targeting the promoter G4 and one targeting Intron 1, were identified with high potential for further development as an innovative approach to both G4 stabilization and MYC modulation.


Assuntos
Quadruplex G , Neoplasias , Oligonucleotídeos , Proteínas Proto-Oncogênicas c-myc , Humanos , Apoptose/genética , DNA/genética , Neoplasias/tratamento farmacológico , Neoplasias/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo
5.
Int J Mol Sci ; 23(23)2022 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-36499587

RESUMO

SARS-CoV-2, a positive-strand RNA virus has caused devastating effects. The standard method for COVID diagnosis is based on polymerase chain reaction (PCR). The method needs expensive reagents and equipment and well-trained personnel and takes a few hours to be completed. The search for faster solutions has led to the development of immunological assays based on antibodies that recognize the viral proteins that are faster and do not require any special equipment. Here, we explore an innovative analytical approach based on the sandwich oligonucleotide hybridization which can be adapted to several biosensing devices including thermal lateral flow and electrochemical devices, as well as fluorescent microarrays. Polypurine reverse-Hoogsteen hairpins (PPRHs) oligonucleotides that form high-affinity triplexes with the polypyrimidine target sequences are used for the efficient capture of the viral genome. Then, a second labeled oligonucleotide is used to detect the formation of a trimolecular complex in a similar way to antigen tests. The reached limit of detection is around 0.01 nM (a few femtomoles) without the use of any amplification steps. The triplex enhanced nucleic acid detection assay (TENADA) can be readily adapted for the detection of any pathogen requiring only the knowledge of the pathogen genome sequence.


Assuntos
COVID-19 , Ácidos Nucleicos , Humanos , SARS-CoV-2/genética , COVID-19/diagnóstico , Oligonucleotídeos/química , Reação em Cadeia da Polimerase , RNA Viral/genética , RNA Viral/análise , Técnicas de Amplificação de Ácido Nucleico/métodos
6.
Int J Mol Sci ; 22(7)2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33917446

RESUMO

Therapeutic strategies for rare diseases based on exon skipping are aimed at mediating the elimination of mutated exons and restoring the reading frame of the affected protein. We explored the capability of polypurine reverse-Hoogsteen hairpins (PPRHs) to cause exon skipping in NB6 cells carrying a duplication of exon 2 of the DHFR gene that causes a frameshift abolishing DHFR activity. METHODS: Different editing PPRHs were designed and transfected in NB6 cells followed by incubation in a DHFR-selective medium lacking hypoxanthine and thymidine. Surviving colonies were analyzed by DNA sequencing, RT-PCR, Western blotting and DHFR enzymatic activity. RESULTS: Transfection of editing PPRHs originated colonies in the DHFR-selective medium. DNA sequencing results proved that the DHFR sequence in all these colonies corresponded to the wildtype sequence with just one copy of exon 2. In the edited colonies, the skipping of the additional exon was confirmed at the mRNA level, the DHFR protein was restored, and it showed high levels of DHFR activity. CONCLUSIONS: Editing-PPRHs are able to cause exon skipping at the DNA level and could be applied as a possible therapeutic tool for rare diseases.


Assuntos
Éxons , Sequências Repetidas Invertidas , RNA Mensageiro , Tetra-Hidrofolato Desidrogenase , Transfecção , Animais , Linhagem Celular Tumoral , Cricetulus , Feminino , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Tetra-Hidrofolato Desidrogenase/biossíntese , Tetra-Hidrofolato Desidrogenase/genética
7.
Int J Mol Sci ; 22(18)2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34576188

RESUMO

PolyPurine Reverse Hoogsteen Hairpins (PPRHs) are gene-silencing DNA-oligonucleotides developed in our laboratory that are formed by two antiparallel polypurine mirror repeat domains bound intramolecularly by Hoogsteen bonds. The aim of this work was to explore the feasibility of using viral vectors to deliver PPRHs as a gene therapy tool. After treatment with synthetic RNA, plasmid transfection, or viral infection targeting the survivin gene, viability was determined by the MTT assay, mRNA was determined by RT-qPCR, and protein levels were determined by Western blot. We showed that the RNA-PPRH induced a decrease in cell viability in a dose-dependent manner and an increase in apoptosis in PC-3 and HeLa cells. Both synthetic RNA-PPRH and RNA-PPRH intracellularly generated upon the transfection of a plasmid vector were able to reduce survivin mRNA and protein levels in PC-3 cells. An adenovirus type-5 vector encoding the PPRH against survivin was also able to decrease survivin mRNA and protein levels, leading to a reduction in HeLa cell viability. In this work, we demonstrated that PPRHs can also work as RNA species, either chemically synthesized, transcribed from a plasmid construct, or transcribed from viral vectors. Therefore, all these results are the proof of principle that viral vectors could be considered as a delivery system for PPRHs.


Assuntos
Inativação Gênica/fisiologia , Adenoviridae/genética , Apoptose/genética , Apoptose/fisiologia , Sobrevivência Celular/genética , Sobrevivência Celular/fisiologia , Células HeLa , Humanos , Oligonucleotídeos/genética , Oligonucleotídeos/metabolismo , Células PC-3 , Survivina/genética , Survivina/metabolismo
8.
Int J Mol Sci ; 21(14)2020 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-32708710

RESUMO

Thymidylate synthase (TYMS) enzyme is an anti-cancer target given its role in DNA biosynthesis. TYMS inhibitors (e.g., 5-Fluorouracil) can lead to drug resistance through an autoregulatory mechanism of TYMS that causes its overexpression. Since G-quadruplexes (G4) can modulate gene expression, we searched for putative G4 forming sequences (G4FS) in the TYMS gene that could be targeted using polypurine reverse Hoogsteen hairpins (PPRH). G4 structures in the TYMS gene were detected using the quadruplex forming G-rich sequences mapper and confirmed through spectroscopic approaches such as circular dichroism and NMR using synthetic oligonucleotides. Interactions between G4FS and TYMS protein or G4FS and a PPRH targeting this sequence (HpTYMS-G4-T) were studied by EMSA and thioflavin T staining. We identified a G4FS in the 5'UTR of the TYMS gene in both DNA and RNA capable of interacting with TYMS protein. The PPRH binds to its corresponding target dsDNA, promoting G4 formation. In cancer cells, HpTYMG-G4-T decreased TYMS mRNA and protein levels, leading to cell death, and showed a synergic effect when combined with 5-fluorouracil. These results reveal the presence of a G4 motif in the TYMS gene, probably involved in the autoregulation of TYMS expression, and the therapeutic potential of a PPRH targeted to the G4FS.


Assuntos
Quadruplex G , Inativação Gênica , Marcação de Genes , Timidilato Sintase/genética , Sequência de Bases , Sobrevivência Celular , DNA/genética , Células HeLa , Humanos , RNA Mensageiro/genética , Sequências Reguladoras de Ácido Nucleico
9.
Compr Rev Food Sci Food Saf ; 17(4): 808-826, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33350112

RESUMO

This paper reviews the potential of stilbenoids as nutraceuticals. Stilbenoid compounds in wine are considered key factors in health-promoting benefits. Resveratrol and resveratrol-related compounds are found in a large diversity of vegetal products. The stilbene composition varies from wine to wine and from one season to another. Therefore, the article also reviews how food science and technology and wine industry may help in providing wines and/or food supplements with efficacious concentrations of stilbenes. The review also presents results from clinical trials and those derived from genomic/transcriptomic studies. The most studied stilbenoid, resveratrol, is a very safe compound. On the other hand, the potential benefits of stilbene intake are multiple and are apparently due to downregulation more than upregulation of gene expression. The field may take advantage from identifying the mechanism of action(s) and from providing useful data to show evidence for specific health benefits in a given tissue or for combating a given disease.

10.
Crit Rev Food Sci Nutr ; 57(16): 3373-3383, 2017 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-26713565

RESUMO

Walnuts are commonly found in our diet and have been recognized for their nutritious properties for a long time. Traditionally, walnuts have been known for their lipid profile, which has been linked to a wide array of biological properties and health-promoting effects. In addition to essential fatty acids, walnuts contain a variety of other bioactive compounds, such as vitamin E and polyphenols. Among common foods and beverages, walnuts represent one of the most important sources of polyphenols, hence their effect over human health warrants attention. The main polyphenol in walnuts is pedunculagin, an ellagitannin. After consumption, ellagitannins are hydrolyzed to release ellagic acid, which is converted by gut microflora to urolithin A and other derivatives such as urolithins B, C, and D. Ellagitannins possess well known antioxidant and anti-inflammatory bioactivity, and several studies have assessed the potential role of ellagitannins against disease initiation and progression, including cancer, cardiovascular, and neurodegenerative diseases. The purpose of this review is to summarize current available information relating to the potential effect of walnut polyphenols in health maintenance and disease prevention.


Assuntos
Juglans , Lipídeos/análise , Polifenóis/análise , Ácido Elágico , Humanos , Nozes/química
11.
Molecules ; 22(9)2017 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-28914822

RESUMO

The search for new alternatives for the prevention and treatment of cancer is extremely important to minimize human mortality. Natural products are an alternative to chemical drugs, since they are a source of many potential compounds with anticancer properties. In the present study, the (2S)-5,7-dihydroxy-6-prenylflavanone (semi-systematic name), also called (2S)-5,7-dihydroxy-6-(3-methyl-2-buten-1-yl)-2-phenyl-2,3-dihydro-4H-1-Benzopyran-4-one (CAS Name registered) (1) was isolated from Eysenhardtia platycarpa leaves. This flavanone 1 was considered as the lead compound to generate new cytotoxic derivatives 1a, 1b, 1c and 1d. These compounds 1, 1a, 1b, 1c, and 1d were then loaded in nanosized drug delivery systems such as polymeric nanoparticles (NPs). Small homogeneous spherical shaped NPs were obtained. Cytotoxic activity of free compounds 1, 1a, 1b, 1c, and 1d and encapsulated in polymeric NPs (NPs1, NPs1a, NPs1b, NPs1c and NPs1d) were evaluated against the pancreatic cancer cell line MiaPaCa-2. The obtained results demonstrated that NPs1a and NPs1b exhibited optimal cytotoxicity, and an even higher improvement of the cytotoxic efficacy was exhibited with the encapsulation of 1a. Based on these results, NPs1a were proposed as promising anticancer agent candidates.


Assuntos
Portadores de Fármacos/química , Fabaceae/química , Flavanonas/química , Nanopartículas/química , Extratos Vegetais/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Liberação Controlada de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Flavanonas/isolamento & purificação , Flavanonas/farmacologia , Humanos , Cinética , Neoplasias Pancreáticas , Tamanho da Partícula , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química , Propriedades de Superfície , Termodinâmica
12.
BMC Immunol ; 17(1): 32, 2016 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-27671753

RESUMO

BACKGROUND: In the context of tumor immunology, tumor cells have been shown to overexpress CD47, an anti-phagocytic signal directed to macrophages to escape from phagocytosis by interacting with Signal Regulatory Protein α SIRPα. In the present work, we designed Polypurine reverse Hoogsteen hairpins, PPRHs, to silence the expression of CD47 in tumor cells and SIRPα in macrophages with the aim to eliminate tumor cells by macrophages in co-culture experiments. METHODS: THP-1 cells were differentiated to macrophages with PMA. The mRNA levels of differentiation markers CD14 and Mcl-1 mRNA and pro-inflammatory cytokines (IL-1ß, IL-18, IL-6, IL-8 and TNF-α) were measured by qRT-PCR. The ability of PPRHs to silence CD47 and SIRPα was evaluated at the mRNA level by qRT-PCR and at the protein level by Western Blot. Macrophages were co-cultured with tumor cells in the presence of PPRHs to silence CD47 and/or SIRPα. Cell viability was assessed by MTT assays. RESULTS: THP-1 cells differentiated to macrophages with PMA showed an increase in macrophage surface markers (CD14, Mcl-1) and pro-inflammatory cytokines (IL-1ß, IL-18, IL-6, IL-8 and TNF-α). PPRHs were able to decrease both CD47 expression in MCF-7 cell line and SIRPα expression in macrophages at the mRNA and protein levels. In the presence of PPRHs, MCF-7 cells were eliminated by macrophages in co-culture experiments, whereas they survived in the absence of PPRHs. CONCLUSIONS: Our data support the usage of PPRHs to diminish CD47/SIRPα interaction by decreasing the expression of both molecules thus resulting in an enhanced killing of MCF-7 cells by macrophages, which might translate into beneficial effects in cancer therapy. These results indicate that PPRHs could represent a new approach with immunotherapeutic applications.

13.
Eur J Nutr ; 55(3): 1099-112, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25962506

RESUMO

PURPOSE: Walnuts contain several bioactive compounds, including pedunculagin, a polyphenol metabolized by microbiota to form urolithins, namely urolithin A (UA). The aim of this study was to determine gene expression changes in prostate cancer cells after incubation with UA. METHODS: We performed a genomic analysis to study the effect of UA on LNCaP prostate cells. Cells were incubated with 40 µM UA for 24 h, and RNA was extracted and hybridized to Affymetrix Human Genome U219 array. Microarray results were analyzed using GeneSpring v13 software. Differentially expressed genes (p < 0.05, fold change > 2) were used to perform biological association networks. Cell cycle was analyzed by flow cytometry and apoptosis measured by the rhodamine method and by caspases 3 and 7 activation. Cell viability was determined by MTT assay. RESULTS: We identified two nodes, FN-1 and CDKN1A, among the differentially expressed genes upon UA treatment. CDKN1A was validated, its mRNA and protein levels were significantly up-regulated, and the promoter activation measured by luciferase. Cell cycle analysis showed an increase in G1-phase, and we also observed an induction of apoptosis and caspases 3 and 7 activation upon UA treatment. CONCLUSION: Our results indicate a potential role of UA as a chemopreventive agent for prostate cancer.


Assuntos
Cumarínicos/farmacologia , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Regulação Neoplásica da Expressão Gênica , Neoplasias da Próstata/genética , Regulação para Cima , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Caspase 3/genética , Caspase 3/metabolismo , Caspase 7/genética , Caspase 7/metabolismo , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p21/genética , Fibronectinas/genética , Fibronectinas/metabolismo , Humanos , Juglans/química , Masculino , Nozes/química , Polifenóis/farmacologia , Neoplasias da Próstata/tratamento farmacológico , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
14.
Mol Pharm ; 12(3): 867-77, 2015 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-25615267

RESUMO

Nowadays, the modulation of gene expression by nucleic acids has become a routine tool in biomedical research for target validation and it is also used to develop new therapeutic approaches. Recently, we developed the so-called polypurine reverse Hoogsteen hairpins (PPRHs) that show high stability and a low immunogenic profile and we demonstrated their efficacy both in vitro and in vivo. In this work, we explored different characteristics of PPRHs to improve their usage as a tool for gene silencing. We studied the role of PPRH length in the range from 20 to 30 nucleotides. We also proved their higher affinity of binding and efficacy on cell viability compared to nonmodified TFOs. To overcome possible off-target effects, we tested wild-type PPRHs, which proved to be capable of binding to their target sequence with more affinity, displaying a higher stability of binding and a higher effect in terms of cell viability. Moreover, we developed a brand new molecule called Wedge-PPRH with the ability to lock the ds-DNA into the displaced structure and proved its efficacy in prostate and breast cancer cell lines.


Assuntos
Inativação Gênica , Sequências Repetidas Invertidas/genética , Biofarmácia , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/terapia , Linhagem Celular Tumoral , Sobrevivência Celular , DNA/química , DNA/genética , Desenho de Fármacos , Feminino , Engenharia Genética , Humanos , Proteínas Inibidoras de Apoptose/genética , Masculino , Conformação de Ácido Nucleico , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/terapia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Neoplásico/genética , RNA Neoplásico/metabolismo , Survivina , Telomerase/genética
15.
Mol Pharm ; 11(1): 254-64, 2014 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-24251728

RESUMO

Gene silencing by either small-interference RNAs (siRNA) or antisense oligodeoxynucleotides (aODN) is widely used in biomedical research. However, their use as therapeutic agents is hindered by two important limitations: their low stability and the activation of the innate immune response. Recently, we developed a new type of molecule to decrease gene expression named polypurine reverse Hoogsteen hairpins (PPRHs) that bind to polypyrimidine targets in the DNA. Herein, stability experiments performed in mouse, human, and fetal calf serum and in PC3 cells revealed that the half-life of PPRHs is much longer than that of siRNAs in all cases. Usage of PPRHs with a nicked-circular structure increased the binding affinity to their target sequence and their half-life in FCS when bound to the target. Regarding the innate immune response, we determined that the levels of the transcription factors IRF3 and its phosphorylated form, as well as NF-κB were increased by siRNAs and not by PPRHs; that the expression levels of several proinflammatory cytokines including IL-6, TNF-α, IFN-α, IFN-ß, IL-1ß, and IL-18 were not significantly increased by PPRHs; and that the cleavage and activation of the proteolytic enzyme caspase-1 was not triggered by PPRHs. These determinations indicated that PPRHs, unlike siRNAs, do not activate the innate inflammatory response.


Assuntos
Neoplasias da Mama/imunologia , Inativação Gênica/imunologia , Neoplasias da Próstata/imunologia , Nucleotídeos de Purina/química , Nucleotídeos de Purina/imunologia , Animais , Western Blotting , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Proliferação de Células , Citocinas/genética , Citocinas/metabolismo , Ensaio de Desvio de Mobilidade Eletroforética , Feminino , Meia-Vida , Humanos , Fator Regulador 3 de Interferon/genética , Fator Regulador 3 de Interferon/metabolismo , Masculino , Camundongos , NF-kappa B/genética , NF-kappa B/metabolismo , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Nucleotídeos de Purina/farmacologia , RNA Mensageiro/genética , RNA Interferente Pequeno/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas
16.
Biomolecules ; 14(4)2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38672408

RESUMO

Transfection agents play a crucial role in facilitating the uptake of nucleic acids into eukaryotic cells offering potential therapeutic solutions for genetic disorders. However, progress in this field needs the development of improved systems that guarantee efficient transfection. Here, we describe the synthesis of a set of chemical delivery agents (TRIFAPYs) containing alkyl chains of different lengths based on the 1,3,5-tris[(4-alkyloxy-1pyridinio)methyl]benzene tribromide structure. Their delivery properties for therapeutic oligonucleotides were evaluated using PolyPurine Reverse Hoogsteen hairpins (PPRHs) as a silencing tool. The binding of liposomes to PPRHs was evaluated by retardation assays in agarose gels. The complexes had a size of 125 nm as determined by DLS, forming well-defined concentrical vesicles as visualized by Cryo-TEM. The prostate cancer cell line PC-3 was used to study the internalization of the nanoparticles by fluorescence microscopy and flow cytometry. The mechanism of entrance involved in the cellular uptake was mainly by clathrin-mediated endocytosis. Cytotoxicity analyses determined the intrinsic toxicity caused by each TRIFAPY and the effect on cell viability upon transfection of a specific PPRH (HpsPr-C) directed against the antiapoptotic target survivin. TRIFAPYs C12-C18 were selected to expand these studies in the breast cancer cell line SKBR-3 opening the usage of TRIFAPYs for both sexes and, in the hCMEC/D3 cell line, as a model for the blood-brain barrier. The mRNA levels of survivin decreased, while apoptosis levels increased upon the transfection of HpsPr-C with these TRIFAPYs in PC-3 cells. Therefore, TRIFAPYs can be considered novel lipid-based vehicles for the delivery of therapeutic oligonucleotides.


Assuntos
Oligonucleotídeos , Transfecção , Humanos , Transfecção/métodos , Oligonucleotídeos/química , Oligonucleotídeos/farmacologia , Linhagem Celular Tumoral , Lipossomos/química , Sobrevivência Celular/efeitos dos fármacos , Nanopartículas/química , Células PC-3 , Masculino
17.
Int J Biol Macromol ; 264(Pt 1): 130540, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38430998

RESUMO

Polypyrimidine sequences can be targeted by antiparallel clamps forming triplex structures either for biosensing or therapeutic purposes. Despite its successful implementation, their biophysical properties remain to be elusive. In this work, PAGE, circular dichroism and multivariate analysis were used to evaluate the properties of PPRHs directed to SARS-CoV-2 genome. Several PPRHs designed to target various polypyrimidine sites within the viral genome were synthesized. These PPRHs displayed varying binding affinities, influenced by factors such as the length of the PPRH and its GC content. The number and position of pyrimidine interruptions relative to the 4 T loop of the PPRH was found a critical factor, affecting the binding affinity with the corresponding target. Moreover, these factors also showed to affect in the intramolecular and intermolecular equilibria of PPRHs alone and when hybridized to their corresponding targets, highlighting the polymorphic nature of these systems. Finally, the functionality of the PPRHs was evaluated in a thermal lateral flow sensing device showing a good correspondence between their biophysical properties and detection limits. These comprehensive studies contribute to the understanding of the critical factors involved in the design of PPRHs for effective targeting of biologically relevant genomes through the formation of triplex structures under neutral conditions.

18.
Colloids Surf B Biointerfaces ; 221: 112968, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36335823

RESUMO

In this study, we assessed the capacity of a previously reported engineered liposomal formulation, which had been tested against model membranes mimicking the lipid composition of the HeLa plasma membrane, to fuse and function as a nanocarrier in cells. We used atomic force microscopy to observe physicochemical changes on the cell surface and confocal microscopy to determine how the liposomes interact with cell membranes and released their load. In addition, we performed viability assays using methotrexate as an active drug to obtain proof of concept of the formulation´s capacity to function as a drug delivery-system. The interaction of engineered liposomes with living cells corroborates the information obtained using model membranes and supports the capacity of the engineered liposomal formulation to serve as a potential nanocarrier.


Assuntos
Sistemas de Liberação de Medicamentos , Lipossomos , Humanos , Lipossomos/química , Transporte Biológico , Membrana Celular/metabolismo , Elasticidade , Cátions/análise
19.
Pharmaceutics ; 15(2)2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36839742

RESUMO

BACKGROUND: One of the most significant limitations that therapeutic oligonucleotides present is the development of specific and efficient delivery vectors for the internalization of nucleic acids into cells. Therefore, there is a need for the development of new transfection agents that ensure a proper and efficient delivery into mammalian cells. METHODS: We describe the synthesis of 1,3,5-tris[(4-oelyl-1-pyridinio)methyl]benzene tribromide (TROPY) and proceeded to the validation of its binding capacity toward oligonucleotides, the internalization of DNA into the cells, the effect on cell viability, apoptosis, and its capability to transfect plasmid DNA. RESULTS: The synthesis and chemical characterization of TROPY, which can bind DNA and transfect oligonucleotides into mammalian cells through clathrin and caveolin-mediated endocytosis, are described. Using a PPRH against the antiapoptotic survivin gene as a model, we validated that the complex TROPY-PPRH decreased cell viability in human cancer cells, increased apoptosis, and reduced survivin mRNA and protein levels. TROPY was also able to stably transfect plasmid DNA, as demonstrated by the formation of viable colonies upon the transfection of a dhfr minigene into dhfr-negative cells and the subsequent metabolic selection. CONCLUSIONS: TROPY is an efficient transfecting agent that allows the delivery of therapeutic oligonucleotides, such as PPRHs and plasmid DNA, inside mammalian cells.

20.
Pharmaceutics ; 15(6)2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37376079

RESUMO

The increasing number of skin cancer cases worldwide and the adverse side effects of current treatments have led to the search for new anticancer agents. In this present work, the anticancer potential of the natural flavanone 1, extracted from Eysenhardtia platycarpa, and four flavanone derivatives 1a-d obtained by different reactions from 1 was investigated by an in silico study and through cytotoxicity assays in melanoma (M21), cervical cancer (HeLa) cell lines and in a non-tumor cell line (HEK-293). The free compounds and compounds loaded in biopolymeric nanoparticles (PLGA NPs 1, 1a-d) were assayed. A structure-activity study (SAR) was performed to establish the main physicochemical characteristics that most contribute to cytotoxicity. Finally, ex vivo permeation studies were performed to assess the suitability of the flavanones for topical administration. Results revealed that most of the studied flavanones and their respective PLGA NPs inhibited cell growth depending on the concentration; 1b should be highlighted. The descriptors of the energetic factor were those that played a more important role in cellular activity. PLGA NPs demonstrated their ability to penetrate (Qp of 17.84-118.29 µg) and be retained (Qr of 0.01-1.44 g/gskin/cm2) in the skin and to exert their action for longer. The results of the study suggest that flavanones could offer many opportunities as a future anticancer topical adjuvant treatment.

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