Peptide nucleic acid (PNA) is a DNA surrogate in which the phosphate deoxyribose backbone of DNA is replaced by repeating N-(2-aminoethyl)glycine units. PNA can hybridize to the complementary DNA and RNA with higher affinity than their oligonucleotide counterparts. This character of PNA not only makes it a new tool for the studies of molecular biology but also the potential candidate for gene-targeting drugs. The non-ionic backbone of PNA leads to stable hybrids with the nucleic acids, but at the same time, the neutral backbone results in poor cellular uptake. To address this problem, studies on modified PNA progress rapidly in recent years. We reviewed literature reports combined with our study about the delivery methods, including backbone modified PNA and PNA-ligand conjugates, and the cellular uptake of modified PNA. In addition, we summarized the problems and future prospect of the cellular delivery of modified PNA.
DNA, Complementary ; Drug Delivery Systems ; Glycine ; analogs & derivatives ; Humans ; Nucleic Acid Hybridization ; Oligonucleotides ; Peptide Nucleic Acids ; chemistry ; RNA

OBJECTIVE: To study the safety and efficiency of the transfection of antisense oligonucletide into kidney mediated by lipid microbubbles, and to evaluate its potential clinical application. METHODS: The potential and conditions regarding the transfection self-made lipid microbubbles (CY5)-labeled-oligonucleotide (ODN) or CY5-labeled-ODN connective tissue growth factor (CTGF) into the rat kidney were evaluated. Th e safety was evaluated by HE staining, liver and renal function tests. The transfection efficiency was evaluated by fluorescence microscopy. Th e expression of CTGF was detected by RT-PCR and Western blot. RESULTS: Self-made lipid microbubble and/or ultrasound significantly enhanced the efficiency of gene transfer and expression in the kidney. Especially, 85%-90% of total glomerular could be transfected. CY5-labeled-ODN expression could be observed in glomerular, tubular and interstitial area. Th ere was no significant change in blood tests aft er gene transfer. Levels of LDH in 7 days were decreased compared with that at the fi rst day aft er the transfection (P<0.05). CTGF expression was successfully suppressed by transfection of CTGF-antisense-ODN into kidney. CONCLUSION The ultrasound-mediated gene transfer by self-made lipid microbubble could enhance the efficiency of ODN and expression in the rat kidney. Th is self-made lipid microbubbles supplement may be use for transfection of target genes.
Animals ; Connective Tissue Growth Factor ; genetics ; metabolism ; Kidney ; metabolism ; Lipids ; chemistry ; Microbubbles ; Oligonucleotides, Antisense ; genetics ; RNA, Messenger ; Rats ; Transfection ; Ultrasonics

BACKGROUND: Several molecular assays have been developed to detect the BRAF V600E mutation in fine needle aspirates (FNAs) for the diagnosis of papillary thyroid cancer. Using a multiplex PCR technique, we evaluated the Anyplex BRAF V600E Real-time Detection (Anyplex) assay and compared its efficacy with that of the Seeplex BRAF V600E ACE Detection (Seeplex) method. METHODS: We tested 258 consecutive FNA specimens using the Seeplex and Anyplex assays. Any conflicting results between the two assays were confirmed by using mutant enrichment with 3'-modified oligonucleotide (MEMO) sequencing. The limits of detection (LODs) and reproducibility for each assay were evaluated with serially diluted DNA from a BRAF V600E-positive cell line. RESULTS: The BRAF V600E mutation was detected in 36.4% (94/258) FNA specimens by either the Seeplex or Anyplex assay. Results for the two assays showed 93.4% (241/258) agreement, with a kappa value of 0.861 (95% confidence interval, 0.798-0.923). Of the eight specimens that were BRAF V600E-positive by the Anyplex assay but not by the Seeplex assay, five were found to be BRAF V600E-positive by MEMO sequencing. The mutation detection rate of the Seeplex and Anyplex assays was 79.0% and 84.0%, respectively, in the FNA specimens diagnosed as malignant (n=81). The LOD as determined by probit analysis was 0.046% (95% confidence interval, 0.019-0.532%). CONCLUSIONS: The Anyplex assay performed better than the Seeplex assay with respect to the detection of the BRAF V600E mutation.
Adult ; Aged ; Asian Continental Ancestry Group/genetics ; Biopsy, Fine-Needle ; DNA/chemistry/metabolism ; DNA Mutational Analysis/*methods ; DNA Primers/*metabolism ; Female ; Humans ; Male ; Middle Aged ; Multiplex Polymerase Chain Reaction ; Oligonucleotides/metabolism ; Polymorphism, Single Nucleotide ; Proto-Oncogene Proteins B-raf/*genetics ; Republic of Korea ; Thyroid Nodule/*metabolism/pathology

In order to obtain nucleotides aptamers bind to IgE, 80 bp nucleotides single-stranded DNA library containing 40 random nucleotides was designed and synthesized. Oligonucleotides that bind to human Cepsilon3-Cepsilon4 protein were isolated from ssDNA pools by the systematic evolution of ligands by exponential enrichment (SELEX) method using nitrocellulose filters as screening medium. Through the optimization of critical PCR and asymmetric PCR parameters including annealing temperature, cycles, and molar ratios of target protein and ssDNA etc, a suitable screening system was established. The aptamers of Cepsilon3-Cepsilon4 protein with high affinity and high specificity were identified by ELISA with biotin-streptavidin-horseradish peroxidase system, and its primary sequence and second structure were analyzed by DNAMAN package and DNA folding sever after being cloned and sequenced. Moreover, target protein was bound to one aptamer and another aptamer modified with biotion together forming a sandwich-like complex, which was captured in microwell to detect IgE concentration using the optimal combination in the sandwich method named enzyme-linked aptamers sorption assay (ELASA). The method could be used for the quantitative detection of human IgE, and whose sensitivity reached to 120 ng x mL(-1).
Aptamers, Nucleotide ; chemistry ; genetics ; isolation & purification ; Base Sequence ; DNA, Single-Stranded ; chemistry ; Humans ; Immunoglobulin epsilon-Chains ; chemistry ; genetics ; Oligonucleotides ; chemistry ; SELEX Aptamer Technique ; methods ; Sensitivity and Specificity

BACKGROUNDThe signal transducer and activator of transcription 6 (STAT6) expression in lung epithelial cells plays a pivotal role in asthma pathogenesis. Activation of STAT6 expression results in T helper cell type 2 (Th2) cell differentiation leading to Th2-mediated IgE production, development of allergic airway inflammation and hyperreactivity. Therefore, antagonizing the expression and/or the function of STAT6 could be used as a mode of therapy for allergic airway inflammation.

METHODSIn this study, we synthesized a 20-mer phosphorothioate antisense oligonucleotide (ASODN) overlapping the translation starting site of STAT6 and constructed STAT6 antisense RNA (pANTI-STAT6), then transfected them into murine spleen lymphocytes and analyzed the effects of antagonizing STAT6 function in vitro and in a murine model of asthma.

RESULTSIn vitro, we showed suppression of STAT6 expression and interleukin (IL)-4 production of lymphocytes by STAT6 ASODN. This effect was more prominent when cells were cultured with pANTI-STAT6. In a murine model of asthma associated with allergic pulmonary inflammation in ovalbumin (OVA)-sensitized mice, local intranasal administration of fluorescein isothiocyanate (FITC)-labeled STAT6 ASODN to DNA uptake in lung cells was accompanied by a reduction of intracellular STAT6 expression. Such intrapulmonary blockade of STAT6 expression abrogated signs of lung inflammation, infiltration of eosinophils and Th2 cytokine production.

CONCLUSIONThese data suggest a critical role of STAT6 in the pathogenesis of asthma and the use of local delivery of STAT6 ASODN as a novel approach for the treatment of allergic airway inflammation such as in asthma.

Animals ; Asthma ; drug therapy ; metabolism ; Blotting, Western ; Cell Differentiation ; drug effects ; Cells, Cultured ; Female ; Interleukin-4 ; metabolism ; Lymphocytes ; drug effects ; metabolism ; Mice ; Mice, Inbred C57BL ; Oligonucleotides, Antisense ; chemistry ; pharmacology ; Phosphates ; pharmacology ; RNA, Antisense ; chemistry ; pharmacology ; Reverse Transcriptase Polymerase Chain Reaction ; STAT6 Transcription Factor ; genetics ; metabolism ; Th2 Cells ; drug effects ; metabolism

OBJECTIVETo establish a single-cell whole genome amplification (WGA) technique, in combination with comparative genomic hybridization (CGH), for analyzing chromosomal copy number changes, and to explore its clinical application in preimplantation genetic diagnosis (PGD).

METHODSTwelve single-cell samples with known karyotypes, including 5 chorionic villus samples, 4 human embryonic stem cell (hESC) samples and 3 peripheral lymphocyte samples, and 4 single blastomere samples carrying chromosomal abnormalities detected by PGD, were collected for whole genome amplification by combining primer extension preamplification (PEP) with degenerate oligonucleotide primed-PCR (DOP-PCR) amplification. The amplified products labeled by red fluorescence were mixed with control DNA labeled by green fluorescence, and then the mixture was analyzed by CGH. As a comparison, 10 single cell samples were amplified by DOP-PCR only and then CGH analysis was performed.

RESULTSThe amplification using PEP-DOP-PCR was more stable than traditional DOP-PCR. The products of PEP-DOP-PCR range from 100 bp to 1000 bp, with the mean size being about 400 bp. The CGH results were consistent with analyses by other methods. However, only 6 out of 10 single cell samples were successfully amplified by DOP-PCR, and CGH analysis showed a high background and 2 samples showed inconsistent results from other methods.

CONCLUSIONPEP-DOP-PCR can effectively amplify the whole genome DNA of single cell. Combined with CGH, this WGA method can successfully detect single-cell chromosomal copy number changes, while DOP-PCR was easy to fail to amplify and amplify inhomogeneously, and CGH analysis using this PCR product usually showed high background. These results suggest that PEP-DOP-CGH is a promising method for preimplantation genetic diagnosis.

Comparative Genomic Hybridization ; methods ; DNA Primers ; Genetic Testing ; methods ; Humans ; Karyotyping ; methods ; Nucleic Acid Amplification Techniques ; methods ; Nucleic Acid Hybridization ; methods ; Oligonucleotides ; chemistry ; Preimplantation Diagnosis ; methods

OBJECTIVETo investigate the specificity of the dual-functionalized nanoparticles probes (NPs) self-assembled with colloidal gold.

METHODS13-nm gold nanoparticles were prepared with citrate reduction of HAuCl(4). These gold nanoparticles were sequentially functionalized with the specific single-strand oligonucleotide of HA gene of influenza A virus (H1N1) and disulfide molecules of m/z at 693. The NPs solution showed the red formation. The magnetic microparticles (MPs) were modified with another specific single-strand oligonucleotide in HA gene of H1N1. The sandwich complexes (MP-Target-NPs) were formed by the target DNA with the MPs and the NPs. The color change in the solution was observed and the dehybridization product was detected by MALDI TOF MS. Moreover specificity of the probes was investigated with nano-water (as a blank control) and the different target DNAs including complementary DNA,non-complementary DNA and two DNAs of one base mismatch, respectively.

RESULTThe red formation and the positive signal in MS detection of reporter mass code 693 ([M+Na](+)) were observed,which indicated the formation of sandwich complexes formed only when the completely complementary target DNAs were presented in the solution. No color formation changes and no peak signal detected by MALDI TOF MS were observed,showing that none of target of interest (nano-pure water),non-complementary DNA and two DNAs of one base mismatch existed in the systems,which indicated no sandwich complexes formed between the target DNAs and the two probes.

CONCLUSIONConsidering the simple preparation procedure and high specificity,the dual-functionalized gold nanoparticle probes would be widely and increasingly used in nucleic acid analysis. In particular,it would have broad application prospects in early diagnosis of diseases,single nucleotide polymorphism (SNP) typing and so on.

DNA Probes ; chemistry ; Gold Colloid ; chemistry ; Influenza A Virus, H1N1 Subtype ; genetics ; Metal Nanoparticles ; chemistry ; Oligonucleotides ; genetics ; Sensitivity and Specificity

OBJECTIVETo investigate the inhibitory effect on HBV replication of antisense locked nucleic acid (LNA) targeting to both S and C genes in HBV transgenic mice.

METHODSThirty HBV transgenic mice were randomly divided into five groups (n = 6): glucose control group were treated with 5% glucose solution, liposome control group were treated with liposome alone, S group were treated with LNA targeting to S gene, C group were treated with LNA targeting to C gene, and dual-target group were treated with LNA targeting to both S and C genes. Antisense LNA was injected into mice via the tail vein. Serum HBsAg was quantified by TRFIA. Serum HBV DNA was quantified by real-time PCR. The expression of HBV C-mRNA in the liver was detected by RT-PCR. The expression of HBsAg and HBcAg in the liver was detected by immunohistochemistry. Serum ALB, ALT, BUN and CR were measured using an automatic biochemical analyzer. The effects of antisense LNA on mouse organs were investigated by HE staining.

RESULTS5 days after LNA injection, serum HBsAg levels in the dual-target group were reduced by 72.8%, and serum HBV DNA levels were decreased by 52.9%. These values were significantly higher than those in the control groups (all P < 0.05). No significant differences were noted in serum ALB, ALT, BUN and CR between the experiment groups and the control groups (all P > 0.05). The expression levels of HBsAg and HBcAg in the liver of dual-target group were significantly lower than those in the control groups. No significant histopathological abnormality was found in liver and kidney tissues in all groups.

CONCLUSIONAntisense LNA targeting to both S and C genes can significantly inhibit HBV replication in transgenic mice.

Animals ; Antiviral Agents ; pharmacology ; DNA, Viral ; blood ; Female ; Hepatitis B Core Antigens ; analysis ; blood ; Hepatitis B Surface Antigens ; analysis ; blood ; Hepatitis B virus ; drug effects ; genetics ; physiology ; Immunohistochemistry ; Injections, Intravenous ; Liposomes ; Liver ; chemistry ; Male ; Mice ; Mice, Transgenic ; Oligonucleotides ; pharmacology ; Oligonucleotides, Antisense ; pharmacology ; Random Allocation ; Transcription, Genetic ; Virus Replication ; drug effects

CpG-Oligodeoxynucleotide (ODN) has two backbones. Phosphorothioate backbone (PS) shows a strong immunostimulating effect while phosphodiester (PE) shows little in vivo. 3' hexameric deoxyriboguanosine-run (3' dG6-run) conjugation to PE CpG-ODN has been reported to enhance immunostimulation and to protect against asthma when injected at the time of sensitization in mice. We evaluated the treatment effects of PE and PS CpG-ODN with or without 3' dG6-run on asthma in presensitized mice. BALB/c mice sensitized with ovalbumin and alum were challenged with 1% ovalbumin on three days. CpG-ODNs (100 microgram) or PBS were injected 4 times; 27 hr before challenge and 3 hr before each challenge (CpG-dG6: CpG-ODN with 3' dG6-run, PE*-CpG-dG6: PE-CpG-dG6 with two PS backbones at the 5' terminus). PE-CpG showed no treatment effect. PE-CpG-dG6 only increased ovalbumin-specific IgG2a. PE*-CpG-dG6 increased ovalbumin-specific IgG2a but also reduced BAL fluid eosinophils and airway hyperresponsiveness. PS-CpG increased ovalbumin-specific IgG2a, reduced airway inflammation and airway hyperresponsiveness. PS-CpG-dG6 was less effective than PS-CpG on airway inflammation and airway hyperresponsiveness. In pre-sensitized mice, PE-CpG required not only 3' dG6-run but also the modification of two PS linkages at 5' terminus to inhibit features of asthma. PS-CpG was strong enough to inhibit asthma but PS-CpG-dG6 was less effective.
Animals ; Anti-Asthmatic Agents/*therapeutic use ; Asthma/*drug therapy/physiopathology ; Bronchial Hyperreactivity/drug therapy ; Bronchoalveolar Lavage Fluid/immunology ; Deoxyguanosine/*analogs & derivatives/*chemistry ; Female ; Immunoglobulin G/metabolism ; Interleukin-12/analysis ; Interleukin-4/analysis ; Interleukin-5/analysis ; Lung/pathology ; Mice ; Mice, Inbred BALB C ; Oligodeoxyribonucleotides/*therapeutic use ; Phosphorothioate Oligonucleotides/therapeutic use ; Splenomegaly/pathology

BACKGROUNDThe failure of hormone treatment for advanced prostate cancer might be related to aberrant activation of the androgen receptor. We have shown that (125)I labeled triple-helix forming oligonucleotide (TFO) against the androgen receptor gene inhibits androgen receptor expression and cell proliferation of LNCaP prostate cancer cells in vitro. This study aimed at exploring the effects of the (125)I-TFO on prostate tumor growth in vivo using a nude mouse xenograft model.

METHODSTFO was labeled with (125)I by the iodogen method. Thirty-two nude mice bearing LNCaP xenograft tumors were randomized into 4 groups and were intratumorally injected with (125)I-TFO, unlabeled TFO, Na(125)I and normal saline. Tumor size was measured weekly. The tumor growth inhibition rate (RI) was calculated by measurement of tumor weight. The expression of the androgen receptor gene was performed by RT-PCR and immunohistochemical study. The prostate specific antigen (PSA) serum levels were measured by enzyme linked immunosorbent assay. The tumor cell apoptosis index (AI) was detected by TUNEL assay.

RESULTSTumor measurements showed that tumor development was significantly inhibited by either (125)I-TFO or TFO, with tumor RIs of 50.79% and 32.80% respectively. (125)I-TFO caused greater inhibition of androgen receptor expression and higher AIs in tumor tissue than TFO. Both the tumor weight and the PSA serum levels in (125)I-TFO treated mice ((0.93 +/- 0.15) g and (17.43 +/- 1.85) ng/ml, respectively) were significantly lower than those ((1.27 +/- 0.21) g and (28.25 +/- 3.41) ng/ml, respectively) in TFO treated mice (all P < 0.05). Na(125)I did not significantly affect tumor growth and androgen receptor expression in tumor tissue.

CONCLUSIONSThe (125)I-TFO can effectively inhibit androgen receptor expression and tumor growth of human prostate cancer xenografts in vivo. The inhibitory efficacy of (125)I-TFO is more potent than that of TFO, providing a reference for future studies of antigen radiotherapy.

Androgen Receptor Antagonists ; Animals ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Enzyme-Linked Immunosorbent Assay ; Humans ; Immunohistochemistry ; Iodine Radioisotopes ; Male ; Mice ; Mice, Inbred BALB C ; Mice, Nude ; Oligonucleotides ; chemistry ; pharmacology ; therapeutic use ; Prostate-Specific Antigen ; blood ; Prostatic Neoplasms ; drug therapy ; metabolism ; pathology ; Receptors, Androgen ; genetics ; metabolism ; Reverse Transcriptase Polymerase Chain Reaction ; Tumor Burden ; drug effects ; Xenograft Model Antitumor Assays ; methods