ObjectiveTo investigate target gene therapy for hepatocellular carcinoma (HCC). MethodsHerpes simplex virus thymidine kinase (HSVTK) gene was inserted into the gene of AFP enhancer/ALB promoter with adenoassociated virus (AAV) plasmid (WAV2) as a carrier, and a hybrid plasmid pWAV2/AFPALB/HYTK was constructed. Besides, plasmid pEGFP1/AFPALB was also constructed. Two kinds of plasmids were transferred into AFP positive cells HepG2 and AFP negative cells 7721, SPC and 7901.ResultsIt was found that enhance green fluorescence protein could only be seen in AFP positive cells HepG2. 710 bp DNA was amplified only in AFP positive HepG2 cells.ConclusionPlasmid pWAV2/AFPALB/HYTK for HCC demonstrates specificity in vitro.
Objective To study the effect of immunogene therapy on the improvement of the outcome of malignant tumor. Methods Literatures about immunogene therapy of malignant tumor were collected and reviewed. Results The major methods of immunogene therapy of malignant tumor were as follows： ①Transference of cytokin genes into lymphocytes. ②Genetically engineered autologous tumor cells used as vaccine. ③Combined gene therapy.Conclusion The therapeutic effect of malignant tumor can be improved by immunogene therapy.
Survivin-D53A (SVV-D53A) is a dominant-negative mutant survivin, which represents a potential promising target for cancer gene therapy. The present study was designed to determine whether SVV-D53A plasmid encapsuled by DOTAP: Chol liposome would have the anti-tumor activity against SPC-A1 lung adenocarcinoma, and to detect the possible mechanisms. In our experiment, SPC-A1 cells were transfected in vitro with SVV-D53A plasmid and examined for protein expression by Western blot, then flow cytometric analysis was used to detect apoptosis. SPC-A1 lung adenocarcinoma xenografts were established in vivo in the nude mice, which received the i.v. administrations of SVV-D53A plasmid/liposome complexes. After mice were sacrificed, the paraffin-embedded tumor tissue sections were used for proliferating cell nuclear antigen (PCNA) expression and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL)assay. Compared with the control group, the mice treated with SVV-D53A plasmid had an obviously reduced tumor volume, with high level of apoptosis and decreased cell proliferation in tumor tissue. The research results proved that the administration of SVV-D53A plasmid resulted in significant inhibition of SPC-A1 cells both in vitro and in vivo. The functional mechanism is that the anti-tumor response causes and induces tumor cell apoptosis.
PNAS-4 is a novel pro-apoptosis gene identified latetly. In recent years, there has been a large number of research reports on the basic studies about PNAS-4 in cancer gene therapy and gene therapy of PNAS-4 alone or combined with chemotherapy or radiotherapy manifested a good application prospect, but its molecular mechanisms to promote apoptosis is not clear yet. In this paper, recent research about PNAS-4 in cancer gene therapy is briefly reviewed, and recent hypotheses on its molecular mechanisms to promote apoptosis are especially elucidated. Based on its newly identified characteristics of structural domain, we made a point that PNAS-4 might regulate functions of some target protein related to apoptosis by deSumoylation as a new deSumoylating isopeptidase, and consequently promote apoptosis.
ObjectiveTo construct tumor specific tubercle bacillus antigen Ag85A gene lentiviral vector driven by murine telomerase catalytic subunit promoter (PmTERT), paving the way for further research in tumor targeting immuno-gene therapy. MethodsPmTERT was amplified by PCR method, with murine genomic DNA as template. Then, transcriptional activities of PmTERT in various murine and human cell strains were studied by luciferase assay. Ag85A expression lentiviral vectors driven by cytomegalo virus (CMV) promoter and PmTERT respectively (pLVX-Ag85ACMV and pLVX-Ag85A-PmTERT) were constructed with nucleic acid cloning approach. And above recombinants were verified with DNA sequencing and Western blot. ResultsLucifease assay revealed that 331 bp PmTERT cloned in present research had transcriptional activity in murine Lewis lung cancer cells, human lung adenocarcinoma cells A549, and human esophageal cancer cells EC-109, while no transcriptional activity in murine fibroblasts NIH3T3 and human embryo fibroblasts MRC-5. Western blot revealed expression of Ag85A in pLVX-Ag85A-CMV transfected Lewis and NIH3T3 cells, pLVX-Ag85A-PmTERT transfected Lewis cells, no expression in pLVX-Ag85A-PmTERT transfected NIH3T3 cells. ConclusionPmTERT has tumor specific transcriptional activity. Ag85A gene can express selectively in tumor cells, driven by PmTERT.
Selective recognition of double strands DNA (dsDNA) has been a research hot spot in molecular biology and biomedicine for a couple decades. Based on the selective interaction between natural nucleic acid/synthetic molecular ligands and dsDNA, gene diagnosis, gene therapy and gene editing would be realized. Hairpin oligopolyamide is a molecular ligand with excellent cellular permeability and nucleases-resistance which can target dsDNA sequence with high affinity and specificity at minor groove. This paper reviews the binding properties and biomedical applications of hairpin oligopolyamide targeting dsDNA, which provide references for further design and application of hairpin oligopolyamide.
Objective To summarize the research progress of microRNA (miRNA) and its non-viral vector in intervertebral disc degeneration (IDD) and to investigate the potential of non-viral vector delivery of miRNA in clinical application. Methods The related literature about the role of miRNA in IDD and its non-viral delivery system was reviewed and analyzed. Results MiRNA can regulate the related gene expression level and further participate in the pathophysiologic process in degenerated intervertebral disc, miRNA delivered by various non-viral vectors has obtained an ideal effect in some diseases. Conclusion MiRNA plays a great role in the cellular and molecular mechanisms of IDD, as a safe and effective strategy for gene therapy, non-viral vector provides new possibilities for IDD treated with miRNA.
Objective To investigate if the course of intervertebral disc degeneration (IDD) is delayed by injecting lentivirus (Lv) vector carrying bone morphogenetic protein 2 (BMP-2) and inhibitor of differentiation 1 (Id1) genes directly into the nucleus pulposus. Methods Thirty-two New Zealand white rabbits, 2.0-2.5 kg in weight and 4 months in age, were used to establish the IDD models at L3, 4, L4, 5, and L5, 6 discs with annular puncture via transabdominal approach. Thirty rabbits with successful modeling were randomly divided into 5 groups, 6 rabbits every group. At 4 weeks after modeling, rabbits were injected with Lv-BMP-2 (group A), with Lv-BMP-2 and Lv-Id1 (group B), with Lv-Id1 (group C), with Lv-green fluorescent protein (group D), and with PBS (group E). At 2, 4, and 8 weeks after injection, T2-mapping MRI was performed on 2 rabbits each group to obtain the T2 values, and then subsequently the lumbar disc tissues were harvested to test the mRNA expressions and contents of collagen type II and proteoglycan by real-time fluorescent quantitative PCR and ELISA methods. Results T2-mapping MRI demonstrated that there was no significant difference in the T2 value between different groups at immediate and 2 weeks after injection (P>0.05). The T2 value of groups A and B was significantly higher than that of groups C, D, and E at 4 weeks after injection (P<0.05), but no significant difference was observed between group A and group B (P>0.05). The T2 value of group B was significantly higher than that of the other groups at 8 weeks after injection (P<0.05). The real-time fluorescent quantitative PCR and ELISA showed that the expressions and contents of collagen type II and proteoglycan in group B were significantly higher than those in the other groups at 2, 4, and 8 weeks after injection (P<0.05). Conclusion Combined application of Lv-BMP-2 and Lv-Id1 can delay IDD changes in rabbit IDD models.
Objective To investigate the effect and mechanism of calcitonin gene-related peptide (CGRP) on the prevention and treatment of transplant vein graft disease. Methods The 25 New Zealand white rabbits were divided into three groups: an experimental group [n=8, the rabbit jugular veins transfected with adeno-associated virus vector tipe 2/1 containing CGRP gene (AAV2/1-CGRP)], a carrier group [n=9, transfected with mosaic adeno-associated virus vector tipe 2/1 containing LacZ gene (AAV2/1-LacZ)] and a control group (n=8, saline) and then the cervical veins were implantated into the ipsilateral carotid artery by reverse end-side anastomosis. At 4 weeks after surgery, the pathology of the specimens, CD68 immunohistochemistry, in situ β-galactosidase staining were obtained. The expression of CGRP gene was detected by reverse transcription-polymerase chain reaction (RT-PCR). Monocyte chemoattractant protein-1(MCP-1), tumour necrosis factor-α (TNF-α), inducible nitric oxide synthase (iNOS) and matrix metalloproteinase-9 (MMP-9) were detected by real-time polymerase chain reaction (real-time PCR). Results The CGRP and LacZ gene expression was positive at postoperative 4 weeks. The intima/media ratio was significantly inhibited in the experimental group. Macrophage infiltration and expression of inflammatory mediators including MCP-1, TNF-α, iNOS and MMP-9 were also significantly inhibited in the experimental group. Conclusion Transfection of AAV2/1-CGRP inhibits inflammatory mediator expression, macrophage infiltration and neointimal hyperplasia in experimental vein graft disease.
ObjectiveTo construct a cationic microbubble (CMB), and investigate the enhancement of gene transfection efficiency and therapeutic effect of ultrasound-targeted microbubble destruction (UTMD) in vivo with CMB compared to definity MB (DMB).Methods In vitro, the CMB was prepared by the method of thin film hydration. The morphology, size, zeta potential, and gene-carrying capacity of CMB were compared with the DMB. In vivo, the firefly luciferase gene which was used as a reporter gene was targeted transfected into myocardium of 16 rats with CMB and DMB, respectively. The gene transfection efficiency and targeting were observed dynamically. Then, ischemia-reperfusion (I/R) model was performed on 64 rats. The models of 60 rats were successfully confirmed by using ultrasonography at 5 days after I/R. The rats were divided into 3 groups (n=20) randomly. The control group received DMB carrying empty plasmid for transfection; DMB group received DMB carrying AKT plasmid for transfection; and CMB group received CMB carrying AKT plasmid for transfection. The cardiac perfusion, cardiac function, infarct size, and infarct thickness were measured by ultrasonography and histological observations after treatment. In addition, the capillary and arteriolar densities were measured with immunohistochemical staining. The myocyte apoptosis was measured with TUNEL staining. The protein expressions of AKT, phospho-AKT (P-AKT), Survivin, and phospho-BAD (P-BAD) were measured by Western blot.ResultsThe size of CMB was uniformly. The zeta potential of CMB was significantly higher than that of DMB (t=28.680, P=0.000). The CMB bound more plasmid DNA than the DMB (P<0.05). The luciferase activity of myocardium were higher in CMB group than in DMB group bothin vitro and in vivo measurements (P<0.05). There was no significant difference between groups in the ratio of signal intensity in anterior wall to posterior wall, ejection fraction (EF), and fractional shortening (FS) at 5 days after I/R (P>0.05), but the above indexes were significant higher in CMB and DMB groups than in control group at 21 days after I/R (P<0.05). Besides, the above indexes were significant higher in CMB group than in DMB group at 21 days after I/R (P<0.05). The infarct size was the smallest and infarct thickness was the thickest in the CMB group, followed by DMB group, control group at 21 days after I/R. The capillary and arteriolar densities of CMB and DMB groups were significant higher than those of control group at 21 days after I/R (P<0.05). Besides, the capillary and arteriolar densities of CMB group were significant higher than those of DMB group (P<0.05). The apoptotic cells were the most in the control group, followed by DMB group, CMB group at 3 days after gene transfection, showing significant differences between groups (P<0.05). The protein expressions of AKT, P-AKT, Survivin, and P-BAD were significant higher in CMB and DMB groups than those in control group at 3 days after gene transfection (P<0.05). Besides, these protein expressions were significant higher in CMB group than those in DMB group (P<0.05).ConclusionThe DNA-carrying capacity and gene transfection efficiency are elevated by CMB, although its physicochemical property is the same as DMB. When ultrasound-targeted AKT gene transfection is used to treat myocardial I/R injury in rats, delivery of AKT with the CMB can result in higher transfection efficiency and greater cardiac functional improvements compared to the DMB.