Molecular therapy to inhibit NFkappaB activation by transcription factor decoy oligonucleotides

NF-κB Decoy Oligodeoxynucleotide-Loaded Poly Lactic-co-glycolic Acid Nanospheres Facilitate Socket Healing in Orthodontic Tooth Movement

Orthodontic space closure following tooth extraction is often hindered by alveolar bone deficiency. This study investigates the therapeutic use of nuclear factor-kappa B (NF-κB) decoy oligodeoxynucleotides loaded with polylactic-co-glycolic acid nanospheres (PLGA-NfDs) to mitigate alveolar bone loss during orthodontic tooth movement (OTM) following the bilateral extraction of maxillary first molars in a controlled experiment involving forty rats of OTM model with ethics approved. The decreased tendency of the OTM distance and inclination angle with increased bone volume and improved trabecular bone structure indicated minimized alveolar bone destruction. Reverse transcription-quantitative polymerase chain reaction and histomorphometric analysis demonstrated the suppression of inflammation and bone resorption by downregulating the expression of tartrate-resistant acid phosphatase, tumor necrosis factor-α, interleukin-1β, cathepsin K, NF-κB p65, and receptor activator of NF-κB ligand while provoking periodontal regeneration by upregulating the expression of alkaline phosphatase, transforming growth factor-β1, osteopontin, and fibroblast growth factor-2. Importantly, relative gene expression over the maxillary second molar compression side in proximity to the alveolus highlighted the pharmacological effect of intra-socket PLGA-NfD administration, as evidenced by elevated osteocalcin expression, indicative of enhanced osteocytogenesis. These findings emphasize that locally administered PLGA-NfD serves as an effective inflammatory suppressor and yields periodontal regenerative responses following tooth extraction.

Nuclear Factor-κB Decoy Oligodeoxynucleotide Attenuates Cartilage Resorption In Vitro

BACKGROUND

Cartilage harvest and transplantation is a common surgery using costal, auricular, and septal cartilage for craniofacial reconstruction. However, absorption and warping of the cartilage grafts can occur due to inflammatory factors associated with wound healing. Transcription factor nuclear factor-κB (NF-κB) is activated by the various stimulation such as interleukin-1 (IL-1), and plays a central role in the transactivation of this inflammatory cytokine gene. Inhibition of NF-κB may have anti-inflammatory effects. The aim of this study was to explore the potential of an NF-κB decoy oligodeoxynucleotide (Decoy) as a chondroprotective agent.

MATERIALS AND METHODS

Safe and efficacious concentrations of Decoy were assessed using rabbit nasal septal chondrocytes (rNSChs) and assays for cytotoxicity, proteoglycan (PG) synthesis, and PG turnover were carried out. The efficacious concentration of Decoy determined from the rNSChs was then applied to human nasal septal cartilage (hNSC) in vitro and analyzed for PG turnover, the levels of inflammatory markers, and catabolic enzymes in explant-conditioned culture medium.

RESULTS

Over the range of Decoy conditions and concentrations, no inhibition of PG synthesis or cytotoxicity was observed. Decoy at 10 μM effectively inhibited PG degradation in the hNSC explant, prolonging PG half-life by 63% and decreasing matrix metalloprotease 3 (MMP-3) by 70.7% (p = 0.027).

CONCLUSIONS

Decoy may be considered a novel chondroprotective therapeutic agent in cartilage transplantation due to its ability to inhibit cartilage degradation due to inflammation cytokines.

NF-κB Decoy ODN-Loaded Poly(Lactic-co-glycolic Acid) Nanospheres Inhibit Alveolar Ridge Resorption

Residual ridge resorption combined with dimensional loss resulting from tooth extraction has a prolonged correlation with early excessive inflammation. Nuclear factor-kappa B (NF-κB) decoy oligodeoxynucleotides (ODNs) are double-stranded DNA sequences capable of downregulating the expression of downstream genes of the NF-κB pathway, which is recognized for regulating prototypical proinflammatory signals, physiological bone metabolism, pathologic bone destruction, and bone regeneration. The aim of this study was to investigate the therapeutic effect of NF-κB decoy ODNs on the extraction sockets of Wistar/ST rats when delivered by poly(lactic-co-glycolic acid) (PLGA) nanospheres. Microcomputed tomography and trabecular bone analysis following treatment with NF-κB decoy ODN-loaded PLGA nanospheres (PLGA-NfDs) demonstrated inhibition of vertical alveolar bone loss with increased bone volume, smoother trabecular bone surface, thicker trabecular bone, larger trabecular number and separation, and fewer bone porosities. Histomorphometric and reverse transcription-quantitative polymerase chain reaction analysis revealed reduced tartrate-resistant acid phosphatase-expressing osteoclasts, interleukin-1β, tumor necrosis factor-α, receptor activator of NF-κB ligand, turnover rate, and increased transforming growth factor-β1 immunopositive reactions and relative gene expression. These data demonstrate that local NF-κB decoy ODN transfection via PLGA-NfD can be used to effectively suppress inflammation in a tooth-extraction socket during the healing process, with the potential to accelerate new bone formation.

Recent advances in inhibiting atherosclerosis and restenosis: from pathogenic factors, therapeutic agents to nano-delivery strategies

Due to dominant atherosclerosis etiology, cardiovascular diseases (CVDs) remain the leading cause of morbidity and mortality worldwide. In clinical trials, advanced atherosclerotic plaques can be removed by angioplasty and vascular...

Recent trends of NFκB decoy oligodeoxynucleotide-based nanotherapeutics in lung diseases

Nuclear factor κB (NFκB) is a unique protein complex that plays a major role in lung inflammation and respiratory dysfunction. The NFκB signaling pathway, therefore becomes an avenue for the development of potential pharmacological interventions, especially in situations where chronic inflammation is often constitutively active and plays a key role in the pathogenesis and progression of the disease. NFκB decoy oligodeoxynucleotides (ODNs) are double-stranded and carry NFκB binding sequences. They prevent the formation of NFκB-mediated inflammatory cytokines and thus have been employed in the treatment of a variety of chronic inflammatory diseases. However, the systemic administration of naked decoy ODNs restricts their therapeutic effectiveness because of their poor pharmacokinetic profile, instability, degradation by cellular enzymes and their low cellular uptake. Both structural modification and nanotechnology have shown promising results in enhancing the pharmacokinetic profiles of potent therapeutic substances and have also shown great potential in the treatment of respiratory diseases such as asthma, chronic obstructive pulmonary disease and cystic fibrosis. In this review, we examine the contribution of NFκB activation in respiratory diseases and recent advancements in the therapeutic use of decoy ODNs. In addition, we also highlight the limitations and challenges in use of decoy ODNs as therapeutic molecules, cellular uptake of decoy ODNs, and the current need for novel delivery systems to provide efficient delivery of decoy ODNs. Furthermore, this review provides a common platform for discussion on the existence of decoy ODNs, as well as outlining perspectives on the latest generation of delivery systems that encapsulate decoy ODNs and target NFκB in respiratory diseases.

Targeted degradation of transcription factors by TRAFTACs: TRAnscription Factor TArgeting Chimeras

Many diseases, including cancer, stem from aberrant activation or overexpression of oncoproteins that are associated with multiple signaling pathways. Although proteins with catalytic activity can be successfully drugged, the majority of other protein families, such as transcription factors, remain intractable due to their lack of ligandable sites. In this study, we report the development of TRAnscription Factor TArgeting Chimeras (TRAFTACs) as a generalizable strategy for targeted transcription factor degradation. We show that TRAFTACs, which consist of a chimeric oligonucleotide that simultaneously binds to the transcription factor of interest (TOI) and to HaloTag-fused dCas9 protein, can induce degradation of the former via the proteasomal pathway. Application of TRAFTACs to two oncogenic TOIs, NF-κB and brachyury, suggests that TRAFTACs can be successfully employed for the targeted degradation of other DNA-binding proteins. Thus, TRAFTAC technology is potentially a generalizable strategy to induce degradation of other transcription factors both in vitro and in vivo.

Engineered DNA nanodrugs alleviate inflammation in inflammatory arthritis

Rheumatoid arthritis (RA) is an autoimmune disease featured with chronic joint inflammation. Suppression of inflammation is critical to RA treatment and joint protection. In this study, DNA nanodrugs are prepared via the conjugation of NF-κB decoy oligodeoxynucleotides (dODNs) and VCAM-1 targeted peptides (P) onto self-assembled DNA tetrahedrons (TDs). Physicochemical properties of DNA nanodrugs are characterized using atomic force microscopy (AFM), gel electrophoresis and Fourier Transform Infrared Spectrometer (FTIR). Cytotoxicity, cellular uptake and anti-inflammatory efficacy of DNA nanodrugs are evaluated in vitro. Clinical arthritis index, inflammatory proteins in serum and joint pathophysiology are also investigated in vivo. TD-P-dODN possesses one dODN and one P and exhibits faster and higher cellular uptake by inflammatory cells compared with free dODNs. TD-P-dODN also significantly reduce inflammatory proteins in cells and adjuvant induced arthritis (AIA) mice. Reduced clinical arthritis index and improved joint rehabilitation are also achieved by TD-P-dODN treatment. This study demonstrates that an engineered DNA nanodrug (TD-P-dODN) enhances the efficacy of nucleic acid drugs and represents a promising strategy for RA treatment.

Nanotechnology in the Treatment of Inflammatory Bowel Disease

Due to the lack of cure for inflammatory bowel disease (IBD) and failure of current medical therapies in many patients with IBD, a need exists in finding novel ways to treat inflammation with a high benefit and the lowest risk possible. With current medical therapies, adverse events or risks of cancer/lymphoma and infections prevent patients-and sometimes providers-in using effective therapies for treatment. Some patients develop systemic side effects that preclude them from continuing a therapy that may have been efficacious, or in other cases, current medical therapies are not adequate to control disease. Nanotechnology is an emerging field where particles, in the size of nanometers, can be used to deliver medications directly to the area of inflammation thus avoiding drug-associated systemic side effects. When using nanoparticles (NPs), only a small amount of the drug is needed, and it can be delivered directly to the inflamed site without exposure to the rest of the body. Here we review conventional and unconventional therapies applied in the treatment of IBD underlying how the introduction of NPs has improved their safety and efficacy.

A Novel Bioabsorbable Sheet That Delivers NF-κB Decoy Oligonucleotide Restrains Abdominal Aortic Aneurysm Development in Rats

For the suppression of inflammation in the aneurysm development, we focused on inhibition of an important transcription factor, nuclear factor-kappa B (NF-κB), using a decoy strategy. We newly developed a novel bioabsorbable sheet that delivers NF-κB decoy oligodeoxynucleotide (ODN).We treated 5-week-old SD rats that were induced with abdominal aortic aneurysm (AAA) using 0.5 M CaCl₂ with an NF-κB decoy sheet. Four weeks after AAA induction, aortic tissue was excised for further examinations. We showed that this bioabsorbable sheet could deliver the decoy ODN into the target tissues and dissolve within a week. Treatment with the NF-κB decoy sheet reduced the aneurysm size compared with the controls. It also suppressed inflammation due to the effect of NF-κB decoy ODN. Immunohistochemistry revealed that the expression of CD31, CD4, and CD11b in the NF-κB decoy sheet group was significantly lower than in the control sheet group. The NF-κB decoy sheet was absorbed on the target tissue.We have revealed that the bioabsorbable sheet mediated decoy ODN is effective for transfection into target organs. We have also indicated that NF-κB decoy ODN transfection using this sheet has the potential to suppress the dilatation of aneurysm. The bioabsorbable sheet mediated transfection of the decoy ODN can be beneficial for the clinical treatment of AAA and other NF-κB-related cardiovascular diseases.

Suppression of chronic inflammation with engineered nanomaterials delivering nuclear factor κB transcription factor decoy oligodeoxynucleotides

As a prototypical pro-inflammatory transcription factor, constitutive activation of NF-κB signaling pathway has been reported in several chronic inflammatory disorders including inflammatory bowel disease, cystic fibrosis, rheumatoid arthritis and cancer. Application of decoy oligodeoxynucleotides (ODNs) against NF-κB, as an effective molecular therapy approach, has brought about several promising outcomes in treatment of chronic inflammatory disorders. However, systematic administration of these genetic constructs is mostly hampered due to their instability, rapid degradation by nucleases and poor cellular uptake. Both chemical modification and application of delivery systems have shown to effectively overcome some of these limitations. Among different administered delivery systems, nanomaterials have gained much attention for delivering NF-κB decoy ODNs owing to their high loading capacity, targeted delivery and ease of synthesis. In this review, we highlight some of the most recently developed nanomaterial-based delivery systems for overcoming limitations associated with clinical application of these genetic constructs.

Ultrasound microbubble-mediated transfection of NF-κB decoy oligodeoxynucleotide into gingival tissues inhibits periodontitis in rats in vivo

Periodontitis is a chronic infectious disease for which the fundamental treatment is to reduce the load of subgingival pathogenic bacteria by debridement. However, previous investigators attempted to implement a nuclear factor kappa B (NF-κB) decoy oligodeoxynucleotide (ODN) as a suppressor of periodontitis progression. Although we recently reported the effectiveness of the ultrasound-microbubble method as a tool for transfecting the NF-κB decoy ODN into healthy rodent gingival tissue, this technique has not yet been applied to the pathological gingiva of periodontitis animal models. Therefore, the aim of this study was to investigate the effectiveness of the technique in transfecting the NF-κB decoy ODN into rats with ligature-induced periodontitis. Micro computed tomography (micro-CT) analysis demonstrated a significant reduction in alveolar bone loss following treatment with the NF-κB decoy ODN in the experimental group. RT-PCR showed that NF-κB decoy ODN treatment resulted in significantly reduced expression of inflammatory cytokine transcripts within rat gingival tissues. Thus, we established a transcutaneous transfection model of NF-κB decoy ODN treatment of periodontal tissues using the ultrasound-microbubble technique. Our findings suggest that the NF-κB decoy ODN could be used as a significant suppressor of gingival inflammation and periodontal disease progression.

A new approach to transfect NF-κB decoy oligodeoxynucleotides into the periodontal tissue using the ultrasound-microbubble method

The objective of this study is to investigate the effect of the ultrasound-microbubble technique in nuclear factor kappa B (NF-κB) decoy oligodeoxynucleotide (ODN) transfection in the gingival tissue in mice. The 6-FAM-labeled scrambled decoy ODN with microbubbles was applied to the periodontal tissue in 8-week-old male C57BL/6J mice by ultrasound radiation at low (LUM-Sc) and high (HUM-Sc) intensities to optimize the transfection condition of the ultrasound-microbubble method. Histological inspections were performed two hours after transfection to compare the expression with that in the sham-operated group without ultrasound radiation (A-Sc). Then, an NF-κB decoy was transfected into the periodontal tissue using the high-intensity ultrasound-microbubble (HUM-NF) technique to examine the anti-inflammatory effects of the decoy ODN. Western blot analysis was performed to investigate the expression of interleukin(IL)-1β, IL-6 and intercellular adhesion molecule-1 (ICAM-1) in the gingival tissues in the HUM-Sc, the HUM-NF and control groups. The fluorescence microscopy results showed that the fluorescent intensity in the periodontal tissues in the LUM-Sc and HUM-Sc groups was significantly higher than that in the A-Sc and the control groups. The fluorescent intensity in the HUM-Sc group, especially in the gingival connective tissue, was the highest of all groups. Western blot analysis indicated that the protein expression levels of IL-1β, IL-6 and ICAM-1 in the HUM-NF group were significantly lower than those in the HUM-Sc and the control groups. These findings suggest that the high-intensity ultrasound-microbubble technique is an effective tool for decoy transfection into the periodontal tissue.

Investigation of the cytokine response to NF-κB decoy oligonucleotide coated polysaccharide based nanoparticles in rheumatoid arthritis in vitro models

Introduction

The transcription factor nuclear factor-kappa B (NF-κB) is highly involved in regulation of a number of cellular processes, including production of inflammatory mediators. Thus, this transcription factor plays a role in pathology of many diseases, including rheumatoid arthritis, an autoimmune disease hallmarked by an imbalance of pro and anti-inflammatory cytokines. Small nucleic acids with sequences that mimic the native binding site of NF-κB have been proposed as treatment options for RA; however due to low cellular penetration and a high degree of instability, clinical applications of these therapeutics have been limited.

Methods

Here, we describe the use of N-trimethyl chitosan-polysialic acid (PSA-TMC) nanoparticles coated with decoy oligodeoxynucleotides (ODNs) specific to transcription factor NF-κB (PSA-TMC-ODN) as a method to enhance the stability of the nucleic acids and facilitate increased cellular penetration. In addition to decoy ODN, PSA-TMC nanoparticles were loaded with RA therapeutic methotrexate (MTX), to assess the anti-inflammatory efficacy of a combination therapy approach. Two different in vitro models, a cell line based model as well as a primary RA cell model were used to investigate anti-inflammatory activity. One way ANOVA followed by Holm-Sidak stepdown comparisons was used to determine statistical significance.

Results

In general, free ODN did not significantly affect secretion of pro-inflammatory cytokines interleukin-6 (IL-6) and interleukin-8, (IL-8) while free MTX had variable efficacy. However, PSA-TMC-ODN and PSA-TMC-ODN-MTX resulted in significant decreases in the inflammatory mediators IL-6 and IL-8 in both cell models. In addition, PSA-TMC exhibited sufficient cellular uptake, as observed through fluorescence microscopy.

Conclusions

These results support our previous findings that PSA-TMC nanoparticles are an effective delivery vehicle for small nucleic acids, and effectively alter the pro-inflammatory state characteristic of RA.

The Role of STAT3 in Non-Small Cell Lung Cancer

Persistent phosphorylation of signal transducer and activator of transcription 3 (STAT3) has been demonstrated in 22%~65% of non-small cell lung cancers (NSCLC). STAT3 activation is mediated by receptor tyrosine kinases, such as epidermal growth factor receptor (EGFR) and MET, cytokine receptors, such as IL-6, and non-receptor kinases, such as Src. Overexpression of total or phosphorylated STAT3 in resected NSCLC leads to poor prognosis. In a preclinical study, overexpression of STAT3 was correlated with chemoresistance and radioresistance in NSCLC cells. Here, we review the role of STAT3 and the mechanisms of treatment resistance in malignant diseases, especially NSCLC. As STAT3 is a critical mediator of the oncogenic effects of EGFR mutations, we discuss STAT3 pathways in EGFR-mutated NSCLC, referring to mechanisms of EGFR tyrosine kinase inhibitor resistance.

Tumour-associated macrophages targeted transfection with NF-κB decoy/mannose-modified bubble lipoplexes inhibits tumour growth in tumour-bearing mice

Tumour-associated macrophages (TAM) exhibit an M2 phenotype that promotes tumour progression, and conversion of M2 TAM toward a tumouricidal M1 phenotype is a promising anti-cancer therapy. As NF-κB is a key regulator of macrophage polarization, we developed an in vivo TAM-targeting delivery system that combines mannose-modified bubble liposomes/NF-κB decoy complexes (Man-PEG bubble lipoplexes) and ultrasound (US) exposure. We investigated the effects of NF-κB decoy transfection on TAM phenotype in solid tumour-bearing mice. Post-transfection tumour growth and survival rates were also recorded. Th2 cytokine (IL-10) level in TAM was significantly lower by NF-κB decoy transfection using Man-PEG bubble lipoplexes and US exposure, while Th1 cytokine levels (IL-1β, TNF-α and IL-6) were significantly higher when compared with controls. In addition, mRNA levels of vascular endothelial growth factor, matrix metalloproteinase-9 and arginase were significantly lower in TAM post-NF-κB decoy transfection. Importantly, TAM-targeted NF-κB decoy transfection inhibited tumour growth and prolonged survival rates in mice. Therefore, TAM-targeted NF-κB decoy transfection using Man-PEG bubble lipoplexes and US exposure may be an effective approach for anti-cancer therapy based on TAM phenotypic conversion from M2 toward M1.

The role of oxidation in FSL-1 induced signaling pathways of an atopic dermatitis model in HaCaT keratinocytes

Oxidative stress (OS) is common in inflammatory conditions and may be important in atopic dermatitis (AD) etiology. The aim of this project was to study the involvement of oxidation in FSL-1 (deacylated lipoprotein)-triggered signaling pathways leading to AD-typical cytokine expression in HaCaT keratinocytes. HaCaT keratinocytes, pretreated with the inhibitor to OS N-acetylcysteine (NAC), were exposed to FSL-1, a stimulator of AD-related cytokines. Cytokines expression was studied by real time polymerase chain reaction (PCR); nuclear factor-kappa B (NF-κB) and p38 mitogen activated protein kinase (MAPK) activities were studied by western blotting; and the oxidative state of cells was determined by the dichlorofluorescein (DCF) assay. We found that endogenous OS in keratinocytes appeared 4 h after FSL-1 administration. OS activated NF-κB, but not p38 MAPK, and the inhibition of OS reduced FSL-1 induced interleukin (IL) 33, thymic stromal lymphopoietin (TSLP) and TNFα mRNA expression. We conclude that FSL-1 triggers an OS reaction in HaCaT keratinocytes, which is probably a secondary event affecting the expression of specific AD typical cytokines, possibly through the NF-κB pathways. This role of OS in the inflammatory response in AD is worth further investigating.

Blockage of STAT3 signaling pathway with a decoy oligodeoxynucleotide inhibits growth of human ovarian cancer cells

Transcription factor decoy oligodeoxynucleotides (ODN) represent a novel tool for targeted inhibition of the STAT3 signaling pathway. To investigate its therapeutic potential in ovarian cancer, a double-stranded decoy ODN mimicking STAT3-specific cis-elements was transfected into two ovarian cancer cell lines OVCAR3 and SKOV3. The STAT3 decoy ODN treatment specifically blocked STAT3 signaling, and inhibited cell proliferation by inducing apoptosis and cell cycle arrest. These results suggest that targeted blockade of the STAT3 signaling pathway with a decoy ODN may represent a potential therapeutic approach in the treatment of ovarian cancer.

Transfection of nuclear factor-kappaB decoy oligodeoxynucleotide protects against ischemia/reperfusion injury in a rat epigastric flap model

BACKGROUND

Nuclear factor-kappaB (NF-κB) is considered to play an important role in the response to ischemia/reperfusion (I/R) injury in flap surgery. To inhibit NF-κB, synthetic double-stranded oligodeoxynucleotide (ODN) was used as a decoy. The present study aimed to evaluate the suppressive effects of NF-κB against I/R injury of experimental rat flap model.

METHODS

An extended epigastric island flap was raised and ischemia was induced for 3 h. NF-κB decoy ODN (group D) or single-strand ODN (control; group S) was injected via the contralateral artery when the pedicle was clamped. Transfection efficiency was evaluated with fluorescein isothiocyanate (FITC)-labeled ODN. The effects of NF-κB decoy ODN were analyzed in groups D and S, and an untreated group (group N).

RESULTS

FITC-labeled ODN was distributed over the entire flap. Mean survival rate of the flap was significantly higher in group D than in the other groups (group D: 57.9%; group S: 31.1%; group N 31.7%; p < 0.005). Injured muscle fibers, neutrophils and the expression of inducible nitric oxide synthase were significantly lower in group D. A real-time polymerase chain reaction also demonstrated a tendency for suppression of tumor necrosis factor-α, interleukin (IL)-1β and IL-6.

CONCLUSIONS

We show that NF-κB decoy ODN protected against flap necrosis as a result of I/R injury in rats. We also indicate that intra-arterial injection of naked NF-κB decoy ODN is effective for transfection into target organs. Therefore, transfection of NF-κB decoy ODN represents a novel therapeutic strategy for the treatment of flap surgery in I/R injury.

In vivo transfection of nuclear factor κB decoy protects pulmonary function against acute lung contusion in rabbits

BACKGROUND

The transcription factor nuclear factor κB (NF-κB) regulates the expression of numerous proinflammatory factors that may exacerbate the response to acute injury. We investigated the effect of an inhibitory NF-κB decoy oligodeoxynucleotide on proinflammatory factor expression and pulmonary function after acute lung contusion in rabbits.

METHODS

Thirty-minutes after acute lung contusion, the NF-κB decoy or a scrambled control oligodeoxynucleotide was injected via the jugular vein. Blood samples were collected for blood gas analysis and plasma tumor necrosis factor α, interleukin 1β (IL-1β), IL-13, and IL-10 were measured by enzyme-linked immunosorbent assay at 1, 2, 3, and 4 hours after contusion. In addition, NF-κB protein expression in lung tissue was detected by Western blot analysis.

RESULTS

The blood PO2 decreased immediately after lung contusion, whereas PAO2 increased significantly, indicative of disrupted respiratory function. Respiratory function improved after sense NF-κB decoy injection but not after injection of the inactive scrambled form. Injection of NF-κB decoy resulted in significant inhibition of NF-κB protein expression in lung tissue and a reduction in the serum concentrations of proinflammatory cytokines tumor necrosis factor α and IL-1β compared with those of control rabbits injected with the scrambled decoy. In contrast, serum levels of the anti-inflammatory cytokines IL-10 and IL-13 increased after decoy injection compared with those of control animals and rabbits injected with the scrambled decoy.

CONCLUSION

The sense NF-κB decoy protected respiratory function and reduced serum proinflammatory factor secretion after acute lung contusion. Inhibition of NF-κB may allow for preservation of pulmonary function for patients with acute lung injury.

Regression of intracranial aneurysms by simultaneous inhibition of nuclear factor-κB and Ets with chimeric decoy oligodeoxynucleotide treatment

BACKGROUND

Despite a high mortality and morbidity of subarachnoid hemorrhage due to an intracranial aneurysm (IA), there is no effective medical treatment to prevent the rupture of IAs. Recent studies have revealed the involvement of the transactivation of proinflammatory genes by nuclear factor-κB (NF-κB) and Ets-1 in the pathogenesis of IA formation and enlargement.

OBJECTIVE

To examine the regressive effect of chimeric decoy oligodeoxynucleotides (ODNs), which simultaneously inhibit NF-κB and Ets-1, on IA development in the rat model.

METHODS

One month after IA induction, rats were treated with NF-κB decoy ODNs or chimeric decoy ODNs. Size, media thickness, macrophage infiltration, and collagen biosynthesis in IA walls were analyzed in both groups.

RESULTS

The treatment with chimeric decoy ODNs decreased IA size and thickened IA walls of preexisting IAs induced in the rat model, although the treatment with NF-κB decoy ODNs failed to regress preexisting IAs. Chimeric decoy ODN-treated rats exhibited decreased expression of monocyte chemotactic protein-1 and macrophage infiltration in IA walls. In addition, decreased collagen biosynthesis in IA walls was ameliorated in the chimeric decoy ODN-treated group.

CONCLUSION

The results suggest the possibility of a minimally invasive molecular therapy targeting the inhibition of NF-κB and ets-1 for IAs in humans.

Recent patents on therapeutic applications of the transcription factor decoy approach

INTRODUCTION

Transcription is considered as an important target of drugs employed in biomedicine. Therefore, novel strategies to inhibit the biological effects of transcription factors (TFs) are of interest, such as targeting promoters with triple-helix-forming oligonucleotides and antisense targeting of mRNAs coding for TFs.

AREAS COVERED

The objective of this review is to describe studies considering inhibition of TF functions with molecules mimicking TF binding sites (transcription factor decoy approach, TFD) and to summarize the patents on possible clinical applications of this approach.

EXPERT OPINION

Treatment of cells with TFD molecules leads to inhibition (or activation) of genes regulated by the target transcription factors. The studies and patents on this specific issue have taken in great consideration the delivery strategy, which is a very important parameter. The TFD strategy has been proven effective in vivo. The stability of the TFD molecules in vivo should be carefully considered, as well as the possible toxicity and/or possible effects on innate and adaptive immune response. In order to improve clinical parameters, many patents suggest the use of the TFD molecules in combination with drugs already employed in therapy. We are expecting in the near future relevant clinical trials based on the TFD strategy.

PGE(2) -EP(2) signalling in endothelium is activated by haemodynamic stress and induces cerebral aneurysm through an amplifying loop via NF-κB

BACKGROUND AND PURPOSE

Cerebral aneurysm is a frequent cerebrovascular event and a major cause of fatal subarachnoid haemorrhage, but there is no medical treatment for this condition. Haemodynamic stress and, recently, chronic inflammation have been proposed as major causes of cerebral aneurysm. Nevertheless, links between haemodynamic stress and chronic inflammation remain ill-defined, and to clarify such links, we evaluated the effects of prostaglandin E(2) (PGE(2) ), a mediator of inflammation, on the formation of cerebral aneurysms.

EXPERIMENTAL APPROACH

Expression of COX and prostaglandin E synthase (PGES) and PGE receptors were examined in human and rodent cerebral aneurysm. The incidence, size and inflammation of cerebral aneurysms were evaluated in rats treated with COX-2 inhibitors and mice lacking each prostaglandin receptor. Effects of shear stress and PGE receptor signalling on expression of pro-inflammatory molecules were studied in primary cultures of human endothelial cells (ECs).

KEY RESULTS

COX-2, microsomal PGES-1 and prostaglandin E receptor 2 (EP(2) ) were induced in ECs in the walls of cerebral aneurysms. Shear stress applied to primary ECs induced COX-2 and EP(2) . Inhibition or loss of COX-2 or EP(2) in vivo attenuated each other's expression, suppressed nuclear factor κB (NF-κB)-mediated chronic inflammation and reduced incidence of cerebral aneurysm. EP(2) stimulation in primary ECs induced NF-κB activation and expression of the chemokine (C-C motif) ligand 2, essential for cerebral aneurysm.

CONCLUSIONS AND IMPLICATIONS

These results suggest that shear stress activated PGE(2) -EP(2) pathway in ECs and amplified chronic inflammation via NF-κB. We propose EP(2) as a therapeutic target in cerebral aneurysm.

Nanomedical system for nucleic acid drugs created with the biodegradable nanoparticle platform

Nanomedical applications of biodegradable poly(DL-lactide-co-glycolide) (PLGA) nanoparticles (NPs) developed are discussed in this review. A surface-functionalized PLGA NP platform for drug delivery was established to encapsulate a number of macromolecular drugs such as peptides and nucleic acids as well as low-molecular-weight drugs by the emulsion solvent diffusion method. The interaction of PLGA NPs with cells and tissues could be controlled by changing the surface properties of NPs, suggesting their potential utility for the intracellular drug delivery of nucleic acid-based drugs. Furthermore, orally administered NF-κB decoy oligonucleotide-loaded CS-PLGA NPs are also useful in treating experimental colitis. These approaches using surface-modified PLGA NPs could be able to open new possibilities for nucleic acid-based drug delivery via noninvasive administration method.

Tyrosine kinases in rheumatoid arthritis

Rheumatoid arthritis (RA) is an inflammatory, polyarticular joint disease. A number of cellular responses are involved in the pathogenesis of rheumatoid arthritis, including activation of inflammatory cells and cytokine expression. The cellular responses involved in each of these processes depends on the specific signaling pathways that are activated; many of which include protein tyrosine kinases. These pathways include the mitogen-activated protein kinase pathway, Janus kinases/signal transducers and activators transcription pathway, spleen tyrosine kinase signaling, and the nuclear factor κ-light-chain-enhancer of activated B cells pathway. Many drugs are in development to target tyrosine kinases for the treatment of RA. Based on the number of recently published studies, this manuscript reviews the role of tyrosine kinases in the pathogenesis of RA and the potential role of kinase inhibitors as new therapeutic strategies of RA.

TNFRp55 modulates IL-6 and nitric oxide responses following Yersinia lipopolysaccharide stimulation in peritoneal macrophages

While cytokines are major regulators of macrophage activation following host-pathogen interactions, they also act to limit inflammation to avoid tissue damage. In previous studies we reported the development of progressive Yersinia enterocolitica-induced reactive arthritis (ReA) in mice lacking the tumor necrosis factor receptor p55 (TNFRp55). In this work, we analyzed the response of TNFRp55⁻/⁻ macrophages to Y. enterocolitica antigens. We found higher concentration of nitric oxide (NO) in TNFRp55⁻/⁻ compared to wild-type macrophages in response to heat-killed Yersinia (HKY) and Yersinia outer membranes (OM). Moreover, Toll-like receptor (TLR)4 expression was increased in OM-stimulated TNFRp55⁻/⁻ versus wild-type (WT) macrophages. Accordingly, NO production was inhibited in TLR4-deficient macrophages following stimulation with OM, suggesting that LPS may function as a major OM component implicated in these responses. Thus, augmented NO production together with enhanced expression of inducible nitric oxide synthase (iNOS) and higher IL-6 production, may provide a pro-inflammatory setting in Yersinia LPS-stimulated TNFRp55⁻/⁻ macrophages. Augmented synthesis of NO and IL-6 was prevented by treatment with Polymyxin B, or by exposure to a specific NF-κB p65 oligonucleotide antisense, indicating the involvement of TLR4-mediated NF-κB activation in the unleashed pro-inflammatory response triggered by TNFRp55 deficiency. Thus, TNFRp55 modulates macrophage functions in response to Yersinia LPS stimulation through mechanisms involving NO, IL-6 and NF-κB pathways, suggesting an essential regulatory role of TNF via TNFRp55 signaling.

Herbal medicinal products target defined biochemical and molecular mediators of inflammatory autoimmune arthritis

Rheumatoid arthritis (RA) is a chronic debilitating disease characterized by synovial inflammation, damage to cartilage and bone, and deformities of the joints. Several drugs possessing anti-inflammatory and immunomodulatory properties are being used in the conventional (allopathic) system of medicine to treat RA. However, the long-term use of these drugs is associated with harmful side effects. Therefore, newer drugs with low or no toxicity for the treatment of RA are actively being sought. Interestingly, several herbs demonstrate anti-inflammatory and anti-arthritic activity. In this review, we describe the role of the major biochemical and molecular mediators in the pathogenesis of RA, and highlight the sites of action of herbal medicinal products that have anti-arthritic activity. With the rapidly increasing use of CAM products by patients with RA and other inflammation-related disorders, our review presents timely information validating the scientific rationale for the use of natural therapeutic products.

The development and the use of experimental animal models to study the underlying mechanisms of CA formation

Cerebral aneurysms (CAs) have a high prevalence and can cause a lethal subarachnoid hemorrhage. Currently, CAs can only be treated with invasive surgical procedures. To unravel the underlying mechanisms of CA formation and to develop new therapeutic drugs for CAs, animal models of CA have been established, modified, and analyzed. Experimental findings from these models have clarified some of the potential mechanisms of CA formation, especially the relationship between hemodynamic stress and chronic inflammation. Increased hemodynamic stress acting at the site of bifurcation of cerebral arteries triggers an inflammatory response mediated by various proinflammatory molecules in arterial walls, inducing pathological changes in the models similar to those observed in the walls of human CAs. Findings from animal studies have provided new insights into CA formation and may contribute to the development of new therapeutic drugs for CAs.

Transfection of NF-κB decoy oligodeoxynucleotide suppresses pulmonary metastasis by murine osteosarcoma

Nuclear factor-kappa B (NF-κB) has a pivotal role in the progression and distant metastasis of cancers, including malignant bone tumors. To inhibit NF-κB activation, a new molecular therapy using synthetic double-stranded oligodeoxynucleotide (ODN) as a 'decoy' cis element against NF-κB has been developed. To determine whether pulmonary metastasis of osteosarcoma is reduced by inhibiting the action of NF-κB, NF-κB decoy ODN was transfected into the nuclei of murine osteosarcoma cells with high pulmonary metastatic potential, the LM8 cell line, using a three-dimensional alginate spheroid culture model. An in vitro study demonstrated the successful transfection of LM8 cells cultured in alginate beads by 'naked' NF-κB decoy ODN and that the activation of NF-κB signaling was significantly suppressed. Tumor growth was not affected by transfection of NF-κB decoy ODN, however, the expression of vascular endothelial growth factor (VEGF) and intercellular adhesion molecule 1 (ICAM-1) mRNA was markedly decreased. Furthermore, the transfection of 'naked' NF-κB decoy ODN effectively suppressed pulmonary metastasis in an in vivo alginate bead transplantation model. Our results suggest that NF-κB has a central and specific role in the regulation of tumor metastasis and could be a molecular target for development of anti-metastatic treatments for osteosarcoma.

Chemosensitization in non-small cell lung cancer cells by IKK inhibitor occurs via NF-kappaB and mitochondrial cytochrome c cascade

In this study, we demonstrated with mechanistic evidence that parthenolide, a sesquiterpene lactone, could antagonize paclitaxel-mediated NF-κB nuclear translocation and activation by selectively targeting I-κB kinase (IKK) activity. We also found that parthenolide could target IKK activity and then inhibit NF-κB; this promoted cytochrome c release and activation of caspases 3 and 9. Inhibition of caspase activity blocked the activation of caspase cascade, implying that the observed synergy was related to caspases 3 and 9 activation of parthenolide. In contrast, paclitaxel individually induced apoptosis via a pathway independent of the mitochondrial cytochrome c cascade. Finally, exposure to parthenolide resulted in the inhibition of several NF-κB transcript anti-apoptotic proteins such as c-IAP1 and Bcl-xl. These data strengthen the rationale for using parthenolide to decrease the apoptotic threshold via caspase-dependent processes for treatment of non-small cell lung cancer with paclitaxel chemoresistance.

Decoy oligodeoxyribonucleotides and peptide nucleic acids-DNA chimeras targeting nuclear factor kappa-B: inhibition of IL-8 gene expression in cystic fibrosis cells infected with Pseudomonas aeruginosa

Cystic fibrosis (CF) is characterized by a deep inflammatory process, with production and release of cytokines and chemokines, among which interleukin 8 (IL-8) represents one of the most important. Accordingly, there is a growing interest in developing therapies against IL-8, with the aim of reducing the excessive inflammatory response in the airways of CF patients. Since transcription factor NF-kappaB plays a critical role in IL-8 expression, the transcription factor decoy (TFD) strategy might be of interest. TFD is based on biomolecules mimicking the target sites of transcription factors (TFs) and able to interfere with TF activity when delivered to target cells. Here, we review the inhibitory effects of decoy oligodeoxyribonucleotides (ODNs) on expression of IL-8 gene and secretion of IL-8 by cystic fibrosis cells infected by Pseudomonas aeruginosa. In addition, the effects of decoy molecules based on peptide nucleic acids (PNAs) are discussed. In this respect PNA-DNA-PNA (PDP) chimeras are interesting: (a) unlike PNAs, they can be complexed with liposomes and microspheres; (b) unlike oligodeoxyribonucleotides (ODNs), they are resistant to DNAses, serum and cytoplasmic extracts; (c) unlike PNA/PNA and PNA/DNA hybrids, they are potent decoy molecules. Interestingly, PDP/PDP NF-kappaB decoy chimeras inhibit accumulation of pro-inflammatory mRNAs (including IL-8 mRNA) in P. aeruginosa infected IB3-1, cells reproducing the effects of decoy oligonucleotides. The effects of PDP/PDP chimeras, unlike ODN-based decoys, are observed even in absence of protection with lipofectamine. Since IL-8 is pivotal in pro-inflammatory processes affecting cystic fibrosis, inhibition of its functions might have a clinical relevance.

Gene therapy targeting nuclear factor-kappaB: towards clinical application in inflammatory diseases and cancer

Nuclear factor (NF)-κB is regarded as one of the most important transcription factors and plays an essential role in the transcriptional activation of pro-inflammatory cytokines, cell proliferation and survival. NF-κB can be activated via two distinct NF-κB signal transduction pathways, the so-called canonical and non-canonical pathways, and has been demonstrated to play a key role in a wide range of inflammatory diseases and various types of cancer. Much effort has been put in strategies to inhibit NF-κB activation, for example by the development of pharmacological compounds that selectively inhibit NF-κB activity and therefore would be beneficial for immunotherapy of transplantation, autoimmune and allergic diseases, as well as an adjuvant approach in patients treated with chemotherapy for cancer. Gene therapy targeting NF-κB is a promising new strategy with the potential of long-term effects and has been explored in a wide variety of diseases, ranging from cancer to transplantation medicine and autoimmune diseases. In this review we discuss recent progress made in the development of NF-κB targeted gene therapy and the evolution towards clinical application.

NFkappaB decoy delivery using dendritic poly(l-lysine) for treatment of endotoxin-induced hepatitis in mice

Mono-dispersed, 6th generation dendritic poly(l-lysine) (KG6) forms a stable complex with plasmid DNA and this complex can circulate in vivo for extended times before the DNA finally accumulates in the liver. In this study, we attempted to use KG6 as a carrier of NFkappaB decoy oligonucleotide to the liver to treat hepatitis, induced by lipopolysaccharide and d-galactosamine. KG6 formed a complex with the NFkappaB decoy. Serum aspartate aminotransferase and alanine aminotransferase were dramatically suppressed in the hepatitis mouse model after intravenous injection of KG6/NFkappaB decoy complexes. Expression levels of several cytokines and proteins related to the inflammatory reaction were also suppressed by intravenous administration of KG6/NFkappaB decoy complexes. Because [(32)P] NFkappaB decoy was found in non-parenchymal cells after intravenous injection, KG6 has been shown to be a promising carrier molecule of various oligonucleotides to non-parenchymal liver cells, including Kupffer cells.

Amelioration of murine dextran sulfate sodium-induced colitis by nuclear factor-kappaB decoy oligonucleotides

BACKGROUND

Activation of nuclear factor (NF)-kappaB has been shown to play a critical role in the pathogenesis of ulcerative colitis (UC). The purpose of the current study was to investigate the effects of NF-kappaB decoy oligonucleotides (ODNs) on an experimental model of UC.

METHODS

NF-kappaB decoy ODNs were administered in experimental colitis induced by dextran sulfate sodium (DSS). The disease activity index (DAI) and histological score were observed. NF-kappaB DNA binding activity was assessed by electrophoretic mobility shift assay (EMSA). The expression of tumor necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta) were measured by reverse transcription polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA).

RESULTS

A significant improvement was observed in DAI and histological score in mice with NF-kappaB decoy ODNs, and the increase in NF-kappaB DNA binding activity, myeloperoxidase (MPO) activity, IL-1beta, and TNF-a in mice with DSS-induced colitis was significantly reduced following administration of NF-kappaB decoy ODNs.

CONCLUSIONS

The administration of NF-kappaB decoy ODNs leads to an amelioration of DSS-induced colitis, suggesting administration of NF-kappaB decoy ODNs may provide a therapeutic approach for UC.

Molecular aspects of rheumatoid arthritis: role of transcription factors

Rheumatoid arthritis is a multifactorial disease characterized by chronic inflammation of the joints. Both genetic and environmental factors are involved in the pathogenesis leading to joint destruction and ultimately disability. In the inflamed RA joint the synovium is highly infiltrated by CD4+ T cells, B cells and macrophages, and the intimal lining becomes hyperplastic owing to the increased number of macrophage-like and fibroblast-like synoviocytes. This hyperplastic intimal synovial lining forms an aggressive front, called pannus, which invades cartilage and bone structures, leading to the destruction and compromised function of affected joints. This process is mediated by a number of cytokines (tumor necrosis factor-alpha, interleukin-1, interleukin-6, interleukin-17 interferon-gamma, etc.), chemokines (monocyte chemoattractant protein-1, monocyte chemoattractant protein-4 CCL18, etc.), cell adhesion molecules (intercellular adhesion molecule-1, vascular cell adhesion molecule-1, etc.) and matrix metalloproteinases. Expression of these molecules is controlled at the transcription level and activation of a limited number of transcription factors is involved in this process.

The IKK-NF-kappaB pathway: a source for novel molecular drug targets in pain therapy?

Several studies indicate that the nuclear factor-kappa B (NF-kappaB) -activation cascade plays a crucial role not only in immune responses, inflammation, and apoptosis but also in the development and processing of pathological pain. Accordingly, a pharmacological intervention into this pathway may have antinociceptive effects and could provide novel treatment strategies for pain and inflammation. In this review we summarize the role of NF-kappaB in the nervous system, its impact on nociception, and several approaches that investigated the effects of various modulators of the classical I-kappaB-kinase-NF-kappaB signal transduction pathway in inflammatory nociception and neuropathic pain. The results indicate that NF-kappaB has an impact on nociceptive transmission and processing and that a number of substances that inhibit the NF-kappaB-activating cascade are capable of reducing the nociceptive response in different animal models. Therefore, a modulation of specific participants in the NF-kappaB signal transduction might exert a useful approach for the development of new painkillers.

Decoy oligodeoxynucleotide targeting activator protein-1 (AP-1) attenuates intestinal inflammation in murine experimental colitis

Various therapies are used for inflammatory bowel diseases (IBD), though none seem to be extremely effective. AP-1 is a major transcription factor that upregulates genes involved in immune and proinflammatory responses. We investigated decoy oligodeoxynucleotide (ODN) targeting AP-1 to prevent dextran sulfate sodium (DSS)-induced colitis in mice. Functional efficacies of synthetic decoy and scrambled ODNs were evaluated in vitro by a reporter gene luciferase assay and measuring flagellin-induced IL-8 expression by HCT-15 cells transfected with ODNs. Experimental colitis was induced in mice with a 2.5% DSS solution in drinking water for 7 days, and decoy or scrambled ODNs were intraperitoneally injected from days 2 to 5. Colitis was assessed by weight loss, colon length, histopathology, and detection of myeloperoxidase (MPO), IL-1beta, and TNF-alpha in colon tissue. Therapeutic effects of AP-1 and NF-kappaB decoy ODNs were compared. Transfection of AP-1 decoy ODN inhibited AP-1 transcriptional activity in reporter assays and flagellin-induced IL-8 production in vitro. In mice, AP-1 decoy ODN, but not scrambled ODN, significantly inhibited weight loss, colon shortening, and histological inflammation induced by DSS. Further, AP-1 decoy ODN decreased MPO, IL-1beta, and TNF-alpha in colonic tissue of mice with DSS-induced colitis. The AP-1 decoy therapeutic effect was comparable to that of NF-kappaB decoy ODN, which also significantly decreased intestinal inflammation. Double-strand decoy ODN targeting AP-1 effectively attenuated intestinal inflammation associated with experimental colitis in mice, indicating the potential of targeting proinflammatory transcription factors in new therapies for IBD.

Blockage of the STAT3 signaling pathway with a decoy oligonucleotide suppresses growth of human malignant glioma cells

Gliomas are the most common type of primary tumor in the human central nervous system. STAT3, a signal transducer and activator of transcription 3, is over expressed in gliomas. Its involvement in tumorgenesis can be attributed to its ability to induce cell proliferation and inhibit apoptosis. Double-stranded decoy oligodeoxynucleotides (ODNs) which correspond closely to the STAT3 response element within the c-fos promoter are a potential tool for inhibiting a variety of tumor cell growth. To investigate its therapeutic potential in malignant gliomas, a 15-mer double-stranded decoy ODN mimicking STAT3-specific cis-elements was transfected into two glioma cell lines, U251 and A172. The STAT3 decoy ODN treatment specifically blocked STAT3 signaling and subsequently inhibited U251 and A172 cell proliferation by inducing apoptosis and cell-cycle arrest. The ODN treatment also decreased transcription and translation of downstream STAT3 target genes including c-myc, cyclin D1 and bcl-xl in both cell lines. Thus, targeted blockade of the STAT3 signaling pathway with a decoy ODN is a potential anti-glioma therapeutic approach.

[Development of cell-selective targeting systems of NFkappaB decoy for inflammation therapy]

NFkappaB regulate several inflammatory related molecules and evoke immune and inflammatory response by several stimuli, therefore inhibition of NFkappaB activation would be a novel therapeutic strategy. To date, there are many conventional drugs including nonsteroldal or steroldal anti-inflammatory drugs or immune suppressors etc. were known to inhibit NFkappaB activation, however, several side effects were also reported. Recently, double stranded oligonucleotide including NFkappaB binding sequence, called NFkappaB decoy, was developed to prevent NFkappaB activation, which is powerful tool in a new class of anti-gene strategy for molecular therapy with low side effect. However, NFkappaB decoy is easily degraded by nuclease and rapidly excreted to urine, therefore it is necessary to develop carrier for NFkappaB decoy therapy. Here, we shall review delivery system for NFkappaB decoy and introduce our cell-selective delivery system for NFkappaB decoy using sugar decorated cationic liposomes.

Growth inhibition of human hepatocellular carcinoma cells by blocking STAT3 activation with decoy-ODN

More and more studies show that signal transducer and activator of transcription 3 (STAT3) is frequently constitutively activated in a wide number of malignancies and named as an attractive molecular target for tumor treatment. Here, we employed STAT3-decoy ODN, which specifically block over-activated STAT3, to treat human hepatocellular carcinoma (HCC) cells, and evaluated the cellular proliferation ability and investigated the molecular mechanisms in vitro. The results demonstrated that the proliferation of HCC cells was suppressed significantly by STAT3-decoy ODN, being associated with the increased apoptosis and cell arrest at G0/G1 to S phase transition. Further investigates showed the expression of STAT3-regulated genes including bcl-x1, cyclin D1 and c-myc, which involved in cell apoptosis and cell cycle progression, were down-regulated significantly both at transcription and translation levels. These data suggested that STAT3 may be potentially used as a molecular target in HCC therapy.

Therapeutic effects of STAT3 decoy oligodeoxynucleotide on human lung cancer in xenograft mice

Background

Signal transducer and activator of transcription 3 (STAT3) is usually constitutively activated in a variety of malignancies. Therefore, STAT3 may be a promising target for treatment of tumor cells. To explore the possibility of a double-stranded decoy oligodeoxynucleotide (ODN) targeted blocking STAT3 over-activated tumor cells, we, here, evaluate the efficacy of STAT3 decoy ODN on human lung cancer cells in vitro and in vivo.

Methods

A STAT3 decoy ODN was transfected into A549 lung cancer cell line in vitro by using lipofectamine. The flow cytometry and fluorescent microscopy were used to detect the transfection efficiency and the sub-cellular localization of STAT3 decoy ODN in A549 cells. Cell proliferation was determined by counting cell numbers and [³H]-thymidine uptake. Cell apoptosis was examined with Annexin V and propidum iodide by flow cytometry. The expression levels of STAT3 target genes were identified by RT-PCR and immunoblot. For in vivo experiment, A549 lung carcinoma-nude mice xenograft was used as a model to examine the effect of the STAT3 decoy by intratumoral injection. At the end of treatment, TUNEL and immunohistochemistry were used to examine the apoptosis and the expression levels of bcl-xl and cyclin D1 in tumor tissues.

Results

STAT3 decoy ODN was effectively transfected into A549 lung cancer cells and mainly located in nucleus. STAT3-decoy ODN significantly induced apoptosis and reduced [³H]-thymidine incorporation of A549 cells as well as down-regulated STAT3-target genes in vitro. STAT3 decoy ODN also dramatically inhibited the lung tumor growth in xenografted nude mice and decreased gene expression of bcl-xl and cyclin D1.

Conclusion

STAT3 decoy ODN significantly suppressed lung cancer cells in vitro and in vivo, indicating that STAT3 decoy ODN may be a potential therapeutic approach for treatment of lung cancer.

Transcription factor decoy oligonucleotide-based therapeutic strategy for renal disease

Renal disease, including slight renal injuries, has come to be seen as one of the risk factors for cardiovascular events. At present, most conventional therapy is inefficient, and tends to treat the symptoms rather than the underlying causes of the disorder. Gene therapy based on oligonucleotides (ODN) offers a novel approach for the prevention and treatment of renal diseases. Gene transfer into somatic cells to interfere with the pathogenesis contributing to renal disease may provide such an approach, leading to the better prevention and treatment of renal disease. The major development of gene transfer methods has made an important contribution to an intense investigation of the potential of gene therapy in renal diseases. Amazing advances in molecular biology have provided the dramatic improvement in the technology that is necessary to transfer target genes into somatic cells. Gene transfer methods, especially when mediated by several viral vectors, have improved to a surprising extent. In fact, some (retroviral vectors, adenoviral vectors, or liposome-based vectors, etc.) have already been used in clinical trials. On the other hand, recent progress in molecular biology has provided new techniques to inhibit target gene expression. The transfer of cis-element double-stranded ODN (= decoy) has been reported to be a powerful novel tool in a new class of antigene strategies for gene therapy. The transfer of decoy ODN corresponding to the cis sequence will result in attenuation of the authentic cis-trans interaction, leading to the removal of trans-factors from the endogenous cis-elements with a subsequent modulation of gene expression.

Characterization of particles fabricated with poly(D, L-lactic-co-glycolic acid) and an ornithine-histidine peptide as carriers of oligodeoxynucleotide for delivery into primary dendritic cells

We report the formulation of particles to deliver oligodeoxynucleotides (ODN) into primary murine dendritic cells (DCs), the most potent antigen-presenting cells (APCs) known, using poly(D,L-lactic-co-glycolic acid) (PLGA) and a small cationic peptide. PLGA polymer and the ODN were fabricated into nano-sized spherical particles with the aid of O10H6 (O = ornithine, H = histidine). We have previously determined that O10H6 condenses DNA and is less toxic to DCs than a similar lysine-based peptide. The colloidal particles are stabilized by negative surface potentials. The peptide and the ODN can be detected in the fabricated particles with reflectance infrared spectroscopy. Significant ODN uptake can be observed in DCs exposed to the particles. Confocal imaging studies reveal that ODN can be internalized and escape from lysosomes in DCs. Taken together, these data suggest that combining PLGA and O10H6 is a feasible method to generate ODN-containing nano-sized particles for applications in DCs.

Inhibitory effect of ribbon-type NF-kappaB decoy oligodeoxynucleotides on osteoclast induction and activity in vitro and in vivo

In this study we examined the effect of ribbon-type (circular-type) NF-κB decoy oligodeoxynucleotides (RNODN) on osteoclast induction and activity. We extracted bone marrow cells from the femurs of rats and incubated non-adherent cells with receptor activator of nuclear factor κB ligand (RANKL) and macrophage colony-stimulating factor (M-CSF). First, transfer efficiency into osteoclasts and their precursors, resistance to exonuclease, and binding activity of decoy to NF-κB were examined. Next, to examine the effect of RNODN on osteoclast induction and activity, osteoclast differentiation and pit formation assays were performed. RNODN were injected into the ankle joints of rats with collagen-induced arthritis. Joint destruction and osteoclast activity were examined by histological study. The resistance of RNODN to exonuclease and their binding activity on NF-κB were both greater than those of phosphorothionated NF-κB decoy oligodeoxynucleotides. The absolute number of multinucleate cells scoring positive for tartrate-resistant acid phosphatase was significantly decreased in the RNODN-treated group. The average calcified matrix resorbed area was significantly decreased in the RNODN-treated group. Histological study showed marked suppression of joint destruction and osteoclast activity by intra-articular injection of RNODN. These results suggest the inhibitory effect of RNODN on the induction and activity of osteoclasts. Direct intra-articular injection of RNODN into the joints may be an effective strategy for the treatment of arthritis.