Delivery of DNAzyme targeting aurora kinase A to inhibit the proliferation and migration of human prostate cancer

Phenylboronic Acid-Modified Polyamidoamine Mediated the Transfection of Polo-Like Kinase-1 siRNA to Achieve an Anti-Tumor Efficacy

Background

The construction of tumor-targeting carriers with favorable transfection efficiency was of great significance to achieve the tumor gene therapy. The phenylboronic acid-modified polyamidoamine (namely PP) was employed as a carrier for the delivery of Polo-like kinase-1 siRNA (siPlk-1), inducing an obvious anti-tumor response.

Materials and Methods

The interaction between PP and siPlk-1 was evaluated by gel retardation assay. The transfection efficiency and tumor-targeting ability were analyzed by flow cytometry and confocal laser scanning microscopy, using hepatocarcinoma cell line HepG2 as a model. The anti-proliferation effect of PP/siPlk-1 and related mechanism were studied using the strategies of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, cell apoptosis and cell cycle arrest. The anti-migration effect induced by PP/siPlk-1 delivery was assayed by wound healing and Transwell migration techniques. Finally, quantitative real-time PCR and Western blotting were performed to measure the expression level of Plk-1 and other key targets.

Results

The derivative PP could achieve the condensation of siPlk-1 into stable nanoparticles at nitrogen/phosphate groups ratio (N/P ratio) of >3.0, and it could facilitate the transfection of siPk-1 in a phenylboronic acid-dependent manner. The PP/siPlk-1 nanoparticles exhibited obvious anti-proliferation effect owing to the gene silence of Plk-1, which was identified to be associated with the cell apoptosis and cell cycle arrest at G2 phase. Meanwhile, PP/siPlk-1 transfection could efficiently suppress the migration and invasion of tumor cells.

Conclusion

The derivative PP has been demonstrated to be an ideal tumor-targeting carrier for the delivery of Plk-1 siRNA, exhibiting great potential in the gene therapy of malignant tumors.

DNAzymes, Novel Therapeutic Agents in Cancer Therapy: A Review of Concepts to Applications

The past few decades have witnessed a rapid evolution in cancer drug research which is aimed at developing active biological interventions to regulate cancer-specific molecular targets. Nucleic acid-based therapeutics, including ribozymes, antisense oligonucleotides, small interference RNA (siRNA), aptamer, and DNAzymes, have emerged as promising candidates regulating cancer-specific genes at either the transcriptional or posttranscriptional level. Gene-specific catalytic DNA molecules, or DNAzymes, have shown promise as a therapeutic intervention against cancer in various in vitro and in vivo models, expediting towards clinical applications. DNAzymes are single-stranded catalytic DNA that has not been observed in nature, and they are synthesized through in vitro selection processes from a large pool of random DNA libraries. The intrinsic properties of DNAzymes like small molecular weight, higher stability, excellent programmability, diversity, and low cost have brought them to the forefront of the nucleic acid-based therapeutic arsenal available for cancers. In recent years, considerable efforts have been undertaken to assess a variety of DNAzymes against different cancers. However, their therapeutic application is constrained by the low delivery efficiency, cellular uptake, and target detection within the tumour microenvironment. Thus, there is a pursuit to identify efficient delivery methods in vivo before the full potential of DNAzymes in cancer therapy is realized. In this light, a review of the recent advances in the use of DNAzymes against cancers in preclinical and clinical settings is valuable to understand its potential as effective cancer therapy. We have thus sought to firstly provide a brief overview of construction and recent improvements in the design of DNAzymes. Secondly, this review stipulates the efficacy, safety, and tolerability of DNAzymes developed against major hallmarks of cancers tested in preclinical and clinical settings. Lastly, the recent advances in DNAzyme delivery systems along with the challenges and prospects for the clinical application of DNAzymes as cancer therapy are also discussed.

Lipoic Acid-Modified Oligoethyleneimine-Mediated miR-34a Delivery to Achieve the Anti-Tumor Efficacy

MiR-34a, an important tumor suppressor, has been demonstrated to possess great potential in tumor gene therapy. To achieve the upregulation of miR-34a expression level, an oligoethyleneimine (OEI) derivative was constructed and employed as the carrier through the modification with lipoic acid (LA), namely LA-OEI. In contrast to OEI, the derivative LA-OEI exhibited superior transfection efficiency measured by confocal laser scanning microscopy and flow cytometry, owing to rapid cargo release in the disulfide bond-based reduction sensitive pattern. The anti-proliferation and anti-migration effects were tested after the miR-34a transfection to evaluate the anti-tumor response, using human cervical carcinoma cell line HeLa as a model. The delivery of LA-OEI/miR-34a nanoparticles could achieve obvious anti-proliferative effect caused by the induction of cell apoptosis and cell cycle arrest at G1 phase. In addition, it could inhibit the migration of tumor cells via the downregulation of MMP-9 and Notch-1 level. Overall, the LA-OEI-mediated miR-34a delivery was potential to be used as an effective way in the tumor gene therapy.

Folate-Mediated Targeted Delivery of siPLK1 by Leucine-Bearing Polyethylenimine

BACKGROUND

siRNA-mediated polo-like kinase 1 (PLK1) silencing has been proposed as a promising therapeutic method for multiple cancers. However, the clinic application of this method is still hindered by the low specific delivery of siPLK1 to desired tumor lesions. Herein, folate (FA)-modified and leucine-bearing polyethylenimine was successfully synthesized and showed excellent targeted silencing to folate receptor overexpressed cells.

MATERIALS AND METHODS

The condensation of siPLK1 by FA-N-Ac-L-Leu-PEI (NPF) was detected by the gel retardation assay. The targeted and silencing efficiency was evaluated by flow cytometry and confocal laser scanning microscope. The PLK1 expressions at gene or protein levels were detected by quantitative real-time PCR and Western blotting assay. Further impacts of the PLK1 silencing on cell viability, cell cycle, migration, and invasion were studied by MTT, colony formation, wound healing and transwell assays.

RESULTS

The NPF and siPLK1 could efficiently assemble to stable nanoparticles at a weight ratio of 3.0 and showed excellent condensation and protection effect. Owing to the FA-mediated targeted delivery, the uptake and silencing efficiency of NPF/siPLK1 to SGC-7901 cells was higher than that without FA modification. Moreover, NPF-mediated PLK1 silencing showed significant antitumor activity in vitro. The anti-proliferation effect of PLK1 silencing was induced via the mitochondrial-dependent apoptosis pathway with the cell cycle arrest of 45% at G2 phase and the apoptotic ratio of 28.3%.

CONCLUSION

FA-N-Ac-L-Leu-PEI (NPF) could generate targeted delivery siPLK1 to FA receptor overexpressed cells and dramatically downregulate the expression of PLK1 expression.

Migration and Proliferation Effects of Thymoquinone-Loaded Nanostructured Lipid Carrier (TQ-NLC) and Thymoquinone (TQ) on In Vitro Wound Healing Models

Wound healing is a regulated biological event that involves several processes including infiltrating leukocyte subtypes and resident cells. Impaired wound healing is one of the major problems in diabetic patients due to the abnormal physiological changes of tissues and cells in major processes. Thymoquinone, a bioactive compound found in Nigella sativa has been demonstrated to possess antidiabetic, anti-inflammatory, and antioxidant effects. Today, the rapidly progressing nanotechnology sets a new alternative carrier to enhance and favour the speed of healing process. In order to overcome its low bioavailability, TQ is loaded into a colloidal drug carrier known as a nanostructured lipid carrier (NLC). This study aimed to determine the effect of TQ-NLC and TQ on cell proliferation and migration, mode of cell death, and the antioxidant levels in normal and diabetic cell models, 3T3 and 3T3-L1. Cytotoxicity of TQ-NLC and TQ was determined by MTT assay. The IC10 values obtained for 3T3-L1 treated with TQ-NLC and TQ for 24 hours were 4.7 ± 3.3 and 5.3 ± 0.6 μM, respectively. As for 3T3, the IC10 values obtained for TQ-NLC and TQ at 24 hours were 4.3 ± 0.17 and 3.9 ± 2.05 μM, respectively. TQ-NLC was observed to increase the number of 3T3 and 3T3-L1 healthy cells (87-95%) and gradually decrease early apoptotic cells in time- and dose-dependant manner compared with TQ. In the proliferation and migration assay, 3T3-L1 treated with TQ-NLC showed higher proliferation and migration rate (p < 0.05) compared with TQ. TQ-NLC also acted as an antioxidant by reducing the ROS levels in both cells after injury at concentration as low as 3 μM. Thus, this study demonstrated that TQ-NLC has better proliferation and migration as well as antioxidant effect compared with TQ especially on 3T3-L1 which confirms its ability as a good antidiabetic and antioxidant agent.

A genipin-crosslinked protein-polymer hybrid system for the intracellular delivery of ribonuclease A

BACKGROUND

Therapeutic proteins have been widely used in the treatment of various diseases, and effective carriers are highly required for achieving protein delivery to obtain favorable treatment potency.

MATERIALS AND METHODS

A protein-polymer hybrid system was constructed through the genipin-mediated crosslinking of polyethyleneimine with a weight-average molecular weight of 25,000 g/mol (PEI25K) and ribonuclease A (RNase A), namely RGP.

RESULTS

The RGP nanoparticles were observed to be easily internationalized in HeLa cells owing to the introduction of positively charged PEI25K, thereby triggering the antiproliferative effects by cleaving RNA molecules in the tumor cells. Moreover, red fluorescence could be obviously visualized in the tumor cells after RGP delivery, which was attributed to the intrinsic characteristics of genipin.

CONCLUSION

The protein-polymer hybrid system prepared via the genipin-mediated crosslinking has exhibited potential to be used as a theranostic platform for both in vivo imaging and delivering diverse therapeutic proteins.

Optimization of an Ultrasound-Assisted Extraction for Simultaneous Determination of Antioxidants in Sesame with Response Surface Methodology

Sesame is a nutritional agricultural product with medicinal properties. Accurate determination of micronutrients is important for the improvement of sesame quality and nutrition assessments. Our previous study showed that 10 antioxidants—d-homoproline, vitamin B₂, coniferyl aldehyde, hesperidin, phloretin, N-acetyl-l-leucine, l-hyoscyamine, ferulic acid, 5-methoxypsoralen, and 8-methoxypsoralen—in sesame were potential characteristic nutrients in sesame. Herein, simultaneous detection of 10 different types of antioxidants was developed by using ultrasound-assisted extraction coupled with liquid chromatography-tandem mass spectrometry (UAE-LC-MS/MS) with the help of response surface methodology. The significant variables and levels were screened and optimized by combining the single factor experiment, Plackett–Burman test, and Box–Behnken design. The optimal conditions for extraction of target antioxidants in sesame were methanol solution of 75.0%, liquid-to-material ratio of 20:1 (mL/g), extraction temperature of 50 °C, extraction power of 410.0 W, extraction time of 65 min. The total yield of targets was 21.74 μg/g under the optimized conditions. The mobile phase used was 0.1% formic acid in acetonitrile and 0.1% formic acid in water, and the column was a Thermo Syncronis C18 reverse phase column (100 mm × 2.1 mm, 3 μm). All targets required only one injection and could be quickly separated and assayed within 7 min. The limits of detection and limits of quantification for these 10 nutritional compounds ranged from 0.01 to 0.11 µg/kg and from 0.04 to 0.34 µg/kg, respectively. The validation results indicated that the method had reasonable linearity (R² ≥ 0.9990), good recoveries (71.1%–118.3%), satisfactory intra-day precision (≤9.6%) and inter-day precision (≤12.9%), and negligible matrix effects (≤13.8%). This simultaneous quantification method was accurate, fast, and robust for the assessment of sesame nutrition.

Inhibition of proliferation and migration of tumor cells through phenylboronic acid-functionalized polyamidoamine-mediated delivery of a therapeutic DNAzyme Dz13

BACKGROUND

The phenylboronic acid-functionalized polyamidoamine (PP) was employed as a gene carrier for Dz13 delivery, inducing an obvious anticancer response.

MATERIALS AND METHODS

The Dz13 condensation ability of PP was evaluated through gel retardation assay. The cellular uptake mechanism of PP/Dz13 nanoparticles was studied using confocal laser scanning microscope and flow cytometer. The inhibition ability of cell proliferation, migration and invasion was investigated through MTT assay, flow cytometry, wound healing and Transwell migration assays, using hepatocarcinoma cell line HepG2 as a model. Finally, Western blotting analysis was used to detect the signaling pathway associated with the inhibition of cell apoptosis and migration induced by Dz13 delivery.

RESULTS

The carrier PP could efficiently condense Dz13 into stable nanoparticles at mass ratios of >1.5. The hydrodynamic diameter and zeta potential of PP/Dz13 nanoparticles were measured to be 204.77 nm and +22.00 mV at a mass ratio of 10.0, respectively. The nanoparticles could realize an efficient cellular uptake in sialic acid-dependent endocytosis manner. Moreover, the nanoparticles exhibited an obvious antiproliferation effect through the induction of cell apoptosis and cell cycle arrest due to the cleavage of c-Jun mRNA. Besides, the suppression of cell migration and invasion could be achieved after the PP/Dz13 transfection, attributing to the decreased expression level of MMP-2 and MMP-9.

CONCLUSION

The PP provided a potential delivery system to achieve the tumor-targeting gene therapy.

A chemoenzymatically synthesized cholesterol-g-poly(amine-co-ester)-mediated p53 gene delivery for achieving antitumor efficacy in prostate cancer

BACKGROUND

An amphiphilic cationic copolymer cholesterol-g-poly(amine-co-ester), namely Chol-g-PMSC-PPDL synthesized in a chemoenzymatic route has been utilized as a carrier for p53 gene delivery to check its antitumor efficacy, using human prostate cancer cell line PC-3 (p53 null) as a model.

MATERIALS AND METHODS

The transfection efficiency was measured by quantitative PCR and Western blotting assay. The anti-proliferative effect was detected using MTT method, colony formation assay and Live/Dead staining. The anti-migration effect was evaluated through wound healing and Transwell migration assays.

RESULTS

The transfection efficiency assay indicated that the carrier-mediated p53 gene transfection could dramatically enhance the intracellular p53 expression level. Through p53 gene delivery, obvious anti-proliferative effect could be detected which was elucidated to be associated with the simultaneous activation of mitochondrial-dependent apoptosis pathway and cell cycle arrest at G1 phase. Meanwhile, the anti-migration effect could be obtained after p53 gene transfection.

CONCLUSION

Chol-g-PMSC-PPDL-mediated p53 gene transfection could potentially be employed as a promising strategy for achieving effective anti-tumor response.

In vitro cellular localization and efficient accumulation of fluorescently tagged biomaterials from monodispersed chitosan nanoparticles for elucidation of controlled release pathways for drug delivery systems

Background

Inefficient cellular delivery and poor intracellular accumulation are major drawbacks towards achieving favorable therapeutic responses from many therapeutic drugs and biomolecules. To tackle this issue, nanoparticle-mediated delivery vectors have been aptly explored as a promising delivery strategy capable of enhancing the cellular localization of biomolecules and improve their therapeutic efficacies. However, the dynamics of intracellular biomolecule release and accumulation from such nanoparticle systems has currently remained scarcely studied.

Objectives

The objective of this study was to utilize a chitosan-based nanoparticle system as the delivery carrier for glutamic acid, a model for encapsulated biomolecules to visualize the in vitro release and accumulation of the encapsulated glutamic acid from chitosan nanoparticle (CNP) systems.

Methods

CNP was synthesized via ionic gelation routes utilizing tripolyphosphate (TPP) as a cross-linker. In order to track glutamic acid release, the glutamic acid was fluorescently-labeled with fluorescein isothiocyanate prior encapsulation into CNP.

Results

Light Scattering data concluded the successful formation of small-sized and mono-dispersed CNP at a specific volume ratio of chitosan to TPP. Encapsulation of glutamic acid as a model cargo into CNP led to an increase in particle size to >100 nm. The synthesized CNP exhibited spherical shape under Electron Microscopy. The formation of CNP was reflected by the reduction in free amine groups of chitosan following ionic crosslinking reactions. The encapsulation of glutamic acid was further confirmed by Fourier Transform Infrared (FTIR) analysis. Cell viability assay showed 70% cell viability at the maximum concentration of 0.5 mg/mL CS and 0.7 mg/mL TPP used, indicating the low inherent toxicity property of this system. In vitro release study using fluorescently-tagged glutamic acids demonstrated the release and accumulation of the encapsulated glutamic acids at 6 hours post treatment. A significant accumulation was observed at 24 hours and 48 hours later. Flow cytometry data demonstrated a gradual increase in intracellular fluorescence signal from 30 minutes to 48 hours post treatment with fluorescently-labeled glutamic acids encapsulated CNP.

Conclusion

These results therefore suggested the potential of CNP system towards enhancing the intracellular delivery and release of the encapsulated glutamic acids. This CNP system thus may serves as a potential candidate vector capable to improve the therapeutic efficacy for drugs and biomolecules in medical as well as pharmaceutical applications through the enhanced intracellular release and accumulation of the encapsulated cargo.

N-AC-l-Leu-PEI-mediated miR-34a delivery improves osteogenic differentiation under orthodontic force

Rare therapeutic genes or agents are reported to control orthodontic bone remodeling. MicroRNAs have recently been associated with bone metabolism. Here, we report the in vitro and in vivo effects of miR-34a on osteogenic differentiation under orthodontic force using an N-acetyl-L-leucine-modified polyethylenimine (N-Ac-l-Leu-PEI) carrier. N-Ac-l-Leu-PEI exhibited low cytotoxicity and high miR-34a transfection efficiency in rat bone mineral stem cells and local alveolar bone tissue. After transfection, miR-34a enhanced the osteogenic differentiation of Runx2 and ColI, Runx2 and ColI protein levels, and early osteogenesis function under orthodontic strain in vitro. MiR-34a also enhanced alveolar bone remodeling under orthodontic force in vivo, as evidenced by elevated gene and protein expression, upregulated indices of alveolar bone anabolism, and diminished tooth movement. We determined that the mechanism miR-34a in osteogenesis under orthodontic force may be associated with GSK-3β. These results suggested that miR-34a delivered by N-Ac-l-Leu-PEI could be a potential therapeutic target for orthodontic treatment.

Gold nanoparticles-based electrochemical method for the detection of protein kinase with a peptide-like inhibitor as the bioreceptor

This article presents a general method for the detection of protein kinase with a peptide-like kinase inhibitor as the bioreceptor, and it was done by converting gold nanoparticles (AuNPs)-based colorimetric assay into sensitive electrochemical analysis. In the colorimetric assay, the kinase-specific aptameric peptide triggered the aggregation of AuNPs in solution. However, the specific binding of peptide to the target protein (kinase) inhibited its ability to trigger the assembly of AuNPs. In the electrochemical analysis, peptides immobilized on a gold electrode and presented as solution triggered together the in situ formation of AuNPs-based network architecture on the electrode surface. Nevertheless, the formation of peptide-kinase complex on the electrode surface made the peptide-triggered AuNPs assembly difficult. Electrochemical impedance spectroscopy was used to measure the change in surface property in the binding events. When a ferrocene-labeled peptide (Fc-peptide) was used in this design, the network of AuNPs/Fc-peptide produced a good voltammetric signal. The competitive assay allowed for the detection of protein kinase A with a detection limit of 20 mU/mL. This work should be valuable for designing novel optical or electronic biosensors and likely lead to many detection applications.