AIM To establish a tissue-specific gene therapy for colorectal carcinoma using bacterial ADP-ribosylating toxin genes.METHODS Pseudomonas exotoxin A domain Ⅱ+Ⅲ (PEA) was cloned from genomic DNA of Pseudomonas aerugi...AIM To establish a tissue-specific gene therapy for colorectal carcinoma using bacterial ADP-ribosylating toxin genes.METHODS Pseudomonas exotoxin A domain Ⅱ+Ⅲ (PEA) was cloned from genomic DNA of Pseudomonas aeruginosa. PEA and diphtheria toxin A chain gene (DTA) were modified to express eukaryotically. After sequencing, the toxin genes under the control of human carcinoembryonic antigen (CEA) promoter were cloned into retroviral vectors to construct CEAPEA and CEADTA respectively. In vitro cotransfection of the constructs with luciferase vectors and in vivo gene transfer in nude mice were subsequently carried out.RESULTS Both CEAPEA and CEADTA specifically inhibited the reporter gene expression in the CEA positive human colorectal carcinoma (CRC) cells in vitro. Direct injection of CEAPEA and CEADTA constructs into the established human tumors in BALB/c nude mice led to significant and selective reductions in CRC tumor size as compared with that in control groups.CONCLUSION The toxin genes, working as therapeutic genes, are suitable for the tissue-specific gene therapy for colorectal carcinoma.展开更多
AIM: To evaluate the possible value of FasL in gastric cancer gene therapy by investigating the effects of FasL expression on human gastric cancer cell line. METHODS: An adenoviral vector encoding the full-length huma...AIM: To evaluate the possible value of FasL in gastric cancer gene therapy by investigating the effects of FasL expression on human gastric cancer cell line. METHODS: An adenoviral vector encoding the full-length human FasL cDNA was constructed and used to infect a human gastric cancer (SGC-7901) cell line. FasL expression was confirmed by X-gal staining, flow cytometric analysis and RT-PCR. The effect of FasL on cell proliferation was determined by clonogenic assay, cytotoxicity was detected by MTT assay, and cell viability was measured by trypan blue exclusion. The therapeutic efficiency of Ad-FasL in vivo was investigated with a xenograft tumor model in nude mice. RESULTS: SGC-7901 cells infected with Ad-FasL showed increased expression of FasL, resulting in significantly decreased cell growth and colony-forming activity when compared with control adenovirus-infected cells. The cytotoxicity of anti-Fas antibody (CH-11) in gastric cancer cells was stronger than that of ActD (91±8 vs60±5,P<0.01), and the cytotoxicity of Ad-FasL was stronger than that of CH-11 (60±5 vs50±2, P<0.05). In addition, G1-phase arrest (67.75±0.39 vs 58.03±2.16, P<0.05) and apoptosis were observed in Ad-FasL-infected SGC-7901 cells, and the growth of SGC-7901 xenografts in nude mice was retarded after intra-tumoral injection with Ad-FasL (54% vs 0%,P<0.0001). CONCLUSION: Infection of human gastric carcinoma cells with Ad-FasL induces apoptosis, indicating that this target gene might be of potential value in gene therapy for gastric cancer.展开更多
To examine the ability of intrastriatal gene transfer of vascular endothelial growth factor 165 mediated by adenoviral vector to rescue dopaminergic neurons in a rat model of Parkinson's disease (PD), we constructe...To examine the ability of intrastriatal gene transfer of vascular endothelial growth factor 165 mediated by adenoviral vector to rescue dopaminergic neurons in a rat model of Parkinson's disease (PD), we constructed recombinant replication-deficent adenoviral vectors carrying the gene of VEGF165 (Ad-VEGF), and injected Ad-VEGF (or Ad-LacZ and PBS as controls) into the striatum of rats 7 days after the lesion by 6-hydroxydopamine. The rat rotational behavior analysis and tyrosine hydroxylase (TH) immunohistochemistry were performed to assess the change of dopaminergic neurons. Our results showed that the rats receiving Ad-VEGF injection displayed a significant improvement in apomorphine-induced rotational behavior and a significant preservation of TH-positive neurons and fibers compared with control animals, It is concluded that intrastriatal gene transfer by Ad-VEGF may rescue the dopaminergic neurons from degeneration in a rat model of PD.展开更多
Objective: To establish an efficient and safe gene transfer system mediated by retrovirus for gene marking and gene therapy of human leukemia. Method: The retroviral vector LXSN, containing the neomycin resistance (Ne...Objective: To establish an efficient and safe gene transfer system mediated by retrovirus for gene marking and gene therapy of human leukemia. Method: The retroviral vector LXSN, containing the neomycin resistance (NeoR) gene, was transferred into amphotropic packaging cells GP+envAm12 by liposome transfection or by ecotropic retrovirus transduction. Amphotropic retrovirus in supernatants with higher titer was used to infect human leukemic cell lines NB4, U937, and THP-1. The efficiency of gene transfer was assayed on colonies formed by transduced K562 cells. Results: The titer of DOSPER directly transfected GP+envAm12 cells determined on NIH3T3 cells was 8.0×105 CFU/ml, while that of producer infected with retrovirus was 1.6×107 CFU/ml. Integration of NeoR gene into all leukemia cells was confirmed by polymerase chain reaction (PCR). Absence of replication-competent virus was proved by both nested PCR for env gene and marker gene rescue assay. Gene transfer with the efficiency as high as 93.3 to 100% in K562 cells was verified by seminested PCR for integrated NeoR gene on colonies after 7 days’ culture. Conclusion: The efficiency and safety of retrovirus mediated gene transfer system might provide an optimal system in gene therapy for leukemia or genetic diseases.展开更多
Exogenous gene suture was used to achieve peripheral nerve anastomoses to probe into the feasibility that the sites of anastomoses of nerves directly transfer gene and thus enable gene to be expressed at the sites of...Exogenous gene suture was used to achieve peripheral nerve anastomoses to probe into the feasibility that the sites of anastomoses of nerves directly transfer gene and thus enable gene to be expressed at the sites of anastomoses under the condition that perfect nerve anastomoses are ensured. PCMVβ plasmid containing cytomegalovirus promoter (CMV promoter) and Escherichia coli (E.coli) β Galactosidase (β Gal) structural gene (lacZ gene) was conducted. A soaked medical 8 0nylon suture was used to perform epineurial repair of rabbit sciatic nerve. In the control group a suture soaked in sucrose PBS was used, while in the experimental group a suture soaked in PCMVβ plasmid solution was applied. The sites of anastomoses of nerves by stages were taken out, and β Gal histochemical staining was performed and β Gal enzyme activity was assayed with 5 bromo 4 chloro 3 indolyl β D galactoside. Results showed that the sites of anastomoses of nerves were taken out 2 days, 7 days, 14 days and 30 days respectively after the operation. The β Gal histochemical stains at the sites of anastomoses showed no indigo positive cells at different stages in the control group, whereas displayed indigo positive cells in the experimental group. In the control group, no β Gal enzyme activity was detected at different stages after operation, but in the experimental group, β Gal enzyme activity could be detected from the 3rd day to the 30th day after operation. It was concluded that by using exogenous gene suture, exogenous gene could be transferred to the sites of peripheral nerve and expressed the exogenous gene expression products with bioactivity, which provided the feasibility of using gene therapy to accelerate the recovery of nerve function.展开更多
Gene therapy has shown great potential to treat various diseases by repairing the abnormal gene function.However,a great challenge in bringing the nucleic acid formulations to the market is the safe and effective deli...Gene therapy has shown great potential to treat various diseases by repairing the abnormal gene function.However,a great challenge in bringing the nucleic acid formulations to the market is the safe and effective delivery to the specific tissues and cells.To be excited,the development of ionizable drug delivery systems(IDDSs)has promoted a great breakthrough as evidenced by the approval of the BNT162b2 vaccine for prevention of coronavirus disease 2019(COVID-19)in 2021.Compared with conventional cationic gene vectors,IDDSs can decrease the toxicity of carriers to cell membranes,and increase cellular uptake and endosomal escape of nucleic acids by their unique pH-responsive structures.Despite the progress,there remain necessary requirements for designing more efficient IDDSs for precise gene therapy.Herein,we systematically classify the IDDSs and summarize the characteristics and advantages of IDDSs in order to explore the underlying design mechanisms.The delivery mechanisms and therapeutic applications of IDDSs are comprehensively reviewed for the delivery of plasmid DNA(pDNA)and four kinds of RNA.In particular,organ selecting considerations and high-throughput screening are highlighted to explore efficiently multifunctional ionizable nanomaterials with superior gene delivery capacity.We anticipate providing references for researchers to rationally design more efficient and accurate targeted gene delivery systems in the future,and indicate ideas for developing next generation gene vectors.展开更多
Genetic diseases seriously threaten human health and have always been one of the refractory conditions facing humanity.Currently,gene therapy drugs such as siRNA,shRNA,antisense oligonucleotide,CRISPR/Cas9 system,plas...Genetic diseases seriously threaten human health and have always been one of the refractory conditions facing humanity.Currently,gene therapy drugs such as siRNA,shRNA,antisense oligonucleotide,CRISPR/Cas9 system,plasmid DNA and miRNA have shown great potential in biomedical applications.To avoid the degradation of gene therapy drugs in the body and effectively deliver them to target tissues,cells and organelles,the development of excellent drug delivery vehicles is of utmost importance.Viral vectors are the most widely used delivery vehicles for gene therapy in vivo and in vitro due to their high transfection efficiency and stable transgene expression.With the development of nanotechnology,novel nanocarriers are gradually replacing viral vectors,emerging superior performance.This review mainly illuminates the current widely used gene therapy drugs,summarizes the viral vectors and non-viral vectors that deliver gene therapy drugs,and sums up the application of gene therapy to treat genetic diseases.Additionally,the challenges and opportunities of the field are discussed from the perspective of developing an effective nano-delivery system.展开更多
OBJECTIVE: To determine the efficacy of adenovirus mediated suicide gene transduction combined with prodrug 5-fluorocytosine (5FC) as a therapeutic protocol for pancreatic cancer. METHODS: Cytosine Deaminase(CD) gene...OBJECTIVE: To determine the efficacy of adenovirus mediated suicide gene transduction combined with prodrug 5-fluorocytosine (5FC) as a therapeutic protocol for pancreatic cancer. METHODS: Cytosine Deaminase(CD) gene was cloned into pAdTrack-CMV-CD, pAdTrack-CMV-CD and pAdEasy-1 were recombined in bacteria. The newly recombined adenovirus (Ad)-CD containing green fluorescent protein (GFP) were packaged and propagated in 293 cells and purified by cesium chloride gradient centrifugation. Human pancreatic carcinoma cell line-Patu8988 was infected with this virus, then 5FC was added. XTT assay was used to estimate relative numbers of viable cells. In vivo model of pancreatic cancer was established by injecting 1.0 x 10(7) Patu8988 cells subcutaneously in Balb/c nude mice. When tumors were palpable, Ad-CD was injected into each tumor and 5FC was administered. RESULTS: Positive clones were selected using endonuclease to digest the recombinants and the concentration of viral liquids containing the CD gene was 2 x 10(11) pfu /ml. Significant cytotoxic activity as shown for 5FC in the CD gene transduced 8988 cell line, while little effect was found in the nontransduced pancreatic carcinoma cells. Antitumor effect was observed in Patu8988 xenograft nude mice with in situ CD gene transduction. CONCLUSIONS: CD gene mediated by adenovirus has high infectivity and may be useful for gene therapy in pancreatic carcinoma. These data demonstrate the use of an enzyme prodrug strategy in experimental pancreatic cancer.展开更多
OBJECTIVE: To explore the inhibitory effect of human endostatin gene mediated by retroviral vector on the growth of human liver carcinoma. METHODS: A recombinant retroviral plasmid containing human endostatin gene and...OBJECTIVE: To explore the inhibitory effect of human endostatin gene mediated by retroviral vector on the growth of human liver carcinoma. METHODS: A recombinant retroviral plasmid containing human endostatin gene and signal peptide was engineered and transferred into PA317 cells to produce retrovirus. Human liver carcinoma cells (SMMC7721) were infected with the above retrovirus to build a stable endostatin-transfected liver carcinoma cell line (SMMC-endo). The control liver carcinoma cell line (SMMC-pLncx) was developed in a similar way except that the plasmid was replaced by an empty retroviral vector. Immunohistochemistry and Western blot were used to test the expression and secretion of human endostatin. The biological activity of the expressed human endostatin was assessed by endothelial cell proliferation assay. The growth rates of SMMC-endo and control SMMC-pLncx cells in vivo and in vitro were also observed. RESULTS: The expression and secretion of human endostatin by endostatin-transfected SMMC-endo cells were confirmed by immunohistochemistry and Western blot. Compared with the control group, concentrated supernatant of SMMC-endo cells remarkably inhibited the proliferation of human umbilical vein endothelial cells by 48%, significantly higher than the inhibition by the control (10.2%; P展开更多
OBJECTIVE: To specifically deliver the therapeutic gene to cancer cells and construct target retroviral vectors by inserting the single-chain variable antibody fragment into the retroviral envelope. METHODS: Single-ch...OBJECTIVE: To specifically deliver the therapeutic gene to cancer cells and construct target retroviral vectors by inserting the single-chain variable antibody fragment into the retroviral envelope. METHODS: Single-chain antibody expression vector pET -20bScfv was constructed. Binding activity of the genetically engineered single-chain variable antibody fragment was verified by enzyme-linked immunosorbent assay (ELISA) and Western blot. At the same time, by means of polymerase chain reaction (PCR)-directed mutagenesis, the appropriate cloning site EcoT22/Sal was generated at the N-terminus of receptor-binding SU domain in the MoMLV env polypeptide. Then the single- chain antibody gene, encoding a functional antibody, was inserted into the cloning site. The Scfv-env fusion gene fragment was subcloned into CMV expression vector. The Lac-Z retrovirus that co-displayed the Scfv-env chimeric protein and wild-type env protein was produced by transfection of Psi 2 cells with retroviral plasmid and the fusion gene expressing plasmid.To confirm the specificity of the recombinant retrovirus, infection assays and competitive inhibition assays were performed. RESULTS: The results of ELISA and Western blot showed that the genetically engineered single-chain variable antibody fragment could bind to the SHG44 cells surface membrane antigen. Virus-binding assay, viral infection and competitive inhibition assays confirmed that the harvested virus efficiently bound to and infected SHG44 cancer cells expressing the relative membrane antigen specially via the recognition of the target antigen. CONCLUSION: These results imply that insertion of Scfv into the retroviral envelope can specifically deliver the interested gene into specific antigen-producing cancer cells.展开更多
To investigate the feasibility and features of 3 catheter mediated approaches o f gene transfer into heart, including direct myocardial injection (DMI), coron ary artery perfusion (CAP), and intrapericardial cavity...To investigate the feasibility and features of 3 catheter mediated approaches o f gene transfer into heart, including direct myocardial injection (DMI), coron ary artery perfusion (CAP), and intrapericardial cavity injection (ICI) Methods Fifteen dogs were used, and 0 3?ml (1×10 9 pfu) of an adenovirus (Adex1SR La cZ) was injected into the heart by 3 methods The dogs were killed 5 days foll owing injection, and gene expressions in heart and liver were evaluated by histochemical analysis Results The results showed that ① the CAP method was relatively less damaging and indu ced sparse LacZ expression in the myocardium, and the gene expression was also f ound in both vessels within the myocardium and liver; ② gene transfer by DMI res ulted in intense LacZ expression around the injection accompanied by a local inf lammatory response; ③ LacZ expression elicited by ICI was detected in either t he inner surface of the parietal pericardium or epicardial surface of the heart, and also in the myocardium underlying the visceral pericardium Conclusion Three catheter mediated methods of gene transfer into the heart may be used a nd a reasonable approach should be chosen according to purpose展开更多
Gastric cancer is common in China [1-42],and its early diagnosis and treatment in advanced stage are difficult [31-50].In recent years ,gene study in cancer is a hotspot ,and great progress has been achieved [41-80] ....Gastric cancer is common in China [1-42],and its early diagnosis and treatment in advanced stage are difficult [31-50].In recent years ,gene study in cancer is a hotspot ,and great progress has been achieved [41-80] .Cancer gene therapy has shifted from the imagination into the laboratory and clinical trials.展开更多
Gene therapy appears as a promising strategy to treatincurable diseases. In particular, combined gene therapy has shown improved therapeutic efficiency. Internal ribosome entry sites(IRESs), RNA elements naturally pre...Gene therapy appears as a promising strategy to treatincurable diseases. In particular, combined gene therapy has shown improved therapeutic efficiency. Internal ribosome entry sites(IRESs), RNA elements naturally present in the 5' untranslated regions of a few m RNAs, constitute a powerful tool to co-express several genes of interest. IRESs are translational enhancers allowing the translational machinery to start protein synthesis by internal initiation. This feature allowed the design of multi-cistronic vectors expressing several genes from a single m RNA. IRESs exhibit tissue specificity, and drive translation in stress conditions when the global cell translation is blocked, which renders them useful for gene transfer in hypoxic conditions occurring in ischemic diseases and cancer. IRES-based viral and non viral vectors have been used successfully in preclinical and clinical assays of combined gene therapy and resulted in therapeutic benefits for various pathologies including cancers, cardiovascular diseases and degenerative diseases.展开更多
Objective: To study the induction of sensitivity toganciclovir (GCV) or acyclovir (ACV) in humanhepatocellular carcinoma (HCC) cell line trans-ferred by an Epstein-Barr virus (EBV)-based repli-con expression vector ca...Objective: To study the induction of sensitivity toganciclovir (GCV) or acyclovir (ACV) in humanhepatocellular carcinoma (HCC) cell line trans-ferred by an Epstein-Barr virus (EBV)-based repli-con expression vector carrying the herpes simplex vi-rus thymidine kinase (HSV-tk) gene, including kill-ing and "bystander" effect, and also the gene delive-ry procedure and route of gene therapy in vivo forHCC.Methods: Liposome-entrapped plasmid pDR2/tk wastransferred into HCC cells, and then different con-centrations of GCV or ACV were added. The trans-ferred cells were mixed with untransferred HCC cellsin different proportion and 200 μmol/L GCV wasthen added into each well. After 72 hours, all sam-ples were measured by MTT colorimetric assay. AnEBV-based plasmid eukarotic expression vector car-rying IL-2 cDNA was used. Three models of gene di-rect injection in the local liver, injection through theportal vein, and injection through the embolized he-patic artery were established in closed Wister rats.For each model, two subgroups, injected either na-ked plasmid DNA or lipofectin-plasmid complex wereincluded. The expression of the IL-2 gene was regu-larly examined immunohistochemically.Results: GCV or ACV could apparently kill thetransferred HCC cells at a concentration of 0. 2μmol/L. The inhibition rate was changed with dif-ferent drug concentrations. The "bystander" effectwas obviously induced at a transferred to untrans-ferred HCC cells ratio of 1:5. IL-2 gene expressionwas observed in liver cells of all animals on day 3,which reached peak within 3-7 days, and declined af-ter day 7. Injection of naked plasmid DNA throughthe hepatic artery plus embolization obtained a bestexpression.Conclusions: EBV-based vector is suitable for carry-ing suicide gene therapy for hepatocellular carcino-ma. Gene direct delivery in vivo combined with in-terventional surgery can be used to treat hepatocellu-lar carcinoma.展开更多
AIM:rAAV mediated endostatin gene therapy has been examined as a new method for treating cancer.However, a sustained and high protein delivery is required to achieve the desired therapeutic effects.We evaluated the im...AIM:rAAV mediated endostatin gene therapy has been examined as a new method for treating cancer.However, a sustained and high protein delivery is required to achieve the desired therapeutic effects.We evaluated the impact of topoisomerase inhibitors in rAAV delivered endostatin gene therapy in a liver tumor model. METHODS:rAAV containing endostatin expression cassettes were transduced into hepatoma cell lines.To test whether the topoisomerase inhibitor pretreatment increased the expression of endostatin,Western blotting and ELISA were performed.The biologic activity of endostatin was confirmed by endothelial cell proliferation and tube formation assays. The anti-tumor effects of the rAAV-endostatin vector combined with a topoisomerase inhibitor,etoposide,were evaluated in a mouse liver tumor model. RESULTS:Topoisomerase inhibitors,including camptothecin and etoposide,were found to increase the endostatin exPression level in vitro.The over-expressed endostatin, as a result of pretreatment with a topoisomerase inhibitor, was also biologically active.In animal experiments,the combined therapy of topoisomerase inhibitor,etoposide with the rAAV-endostatin vector had the best tumor- suppressive effect and tumor foci were barely observed in livers of the treated mice.Pretreatment with an etoposide increased the level of endostatin in the liver and serum of rAAV-endostatin treated mice.Finally,the mice treated With rAAV-endostatin in combination with etoposide showed the longest survival among the experimental models. CONCLUSION:rAAV delivered endostatin gene therapy in combination with a topoisomerase inhibitor pretreatment is an effective modality for anticancer gene therapy.展开更多
Apoptosis,a key mechanism of programmed cell death,is triggered by caspase-3 protein and lowering its levels with gene therapy may rescue cell death after central nervous system damage.We developed a novel,non-viral g...Apoptosis,a key mechanism of programmed cell death,is triggered by caspase-3 protein and lowering its levels with gene therapy may rescue cell death after central nervous system damage.We developed a novel,non-viral gene therapy to block caspase-3 gene expression using small interfering RNA(siRNA)delivered by polybutylcyanoacrylate nanoparticles(CaspNPs).In vitro CaspNPs significantly blocked caspase-3 protein expression in C6 cells,and when injected intraocularly in vivo,CaspNPs lowered retinal capsase-3 immunofluorescence by 57.9%in rats with optic nerve crush.Longitudinal,repeated retinal ganglion cell counts using confocal neuroimaging showed that post-traumatic cell loss after intraocular CaspNPs injection was only 36.1%versus 63.4%in lesioned controls.Because non-viral gene therapy with siRNA-nanoparticles can selectively silence caspace-3 gene expression and block apoptosis in post-mitotic neurons,siRNA delivery with nanoparticles may be promising for neuroprotection or restoration of central visual system damage and other neurological disorders.The animal study procedures were approved by the German National Act on the use of experimental animals(Ethic Committee Referat Verbraucherschutz,Veterinärangelegenheiten;Landesverwaltungsamt Sachsen-Anhalt,Halle,Germany,#IMP/G/01-1150/12 and#IMP/G/01-1469/17).展开更多
This narrative review highlights routes of ocular drug delivery for age-related macular degeneration(AMD).AMD is the leading cause of irreversible blindness in industrialized countries and accounts for 8.7%of blindnes...This narrative review highlights routes of ocular drug delivery for age-related macular degeneration(AMD).AMD is the leading cause of irreversible blindness in industrialized countries and accounts for 8.7%of blindness worldwide.Advanced AMD can be classified into two subtypes:late-stage dry AMD[known as geographic atrophy(GA)]and neovascular AMD(nAMD).GA is often bilateral and results from progressive and irreversible loss of photoreceptors and areas of the retinal pigment epithelium.Wet AMD is characterized by angiogenesis from the choroid to the normally avascular regions underneath the retinal pigment epithelium(RPE)or retina,a process known as choroidal neovascularization(CNV).Various targeted therapeutic options are currently available to reduce the progression rate and maintain vision in patients with nAMD.Intravitreal delivery of anti-VEGF protein treatments to halt CNV is currently the gold-standard of care for nAMD.Subretinal and suprachoroidal delivery approaches are also being explored for gene and molecular therapies.Advancements in nanotechnology and biomaterials have also led to the development of microscopic drug delivery systems,including hydrogels,microparticles,nanoparticles,implants,and liposomes.Gene therapy and stem cell therapy has recently emerged as a potential candidate treatment modality for AMD and other retinal degenerations.New drug targets and modalities have stimulated exciting developments in ocular drug delivery with the promise of greater efficacy and durability of AMD treatment.展开更多
文摘AIM To establish a tissue-specific gene therapy for colorectal carcinoma using bacterial ADP-ribosylating toxin genes.METHODS Pseudomonas exotoxin A domain Ⅱ+Ⅲ (PEA) was cloned from genomic DNA of Pseudomonas aeruginosa. PEA and diphtheria toxin A chain gene (DTA) were modified to express eukaryotically. After sequencing, the toxin genes under the control of human carcinoembryonic antigen (CEA) promoter were cloned into retroviral vectors to construct CEAPEA and CEADTA respectively. In vitro cotransfection of the constructs with luciferase vectors and in vivo gene transfer in nude mice were subsequently carried out.RESULTS Both CEAPEA and CEADTA specifically inhibited the reporter gene expression in the CEA positive human colorectal carcinoma (CRC) cells in vitro. Direct injection of CEAPEA and CEADTA constructs into the established human tumors in BALB/c nude mice led to significant and selective reductions in CRC tumor size as compared with that in control groups.CONCLUSION The toxin genes, working as therapeutic genes, are suitable for the tissue-specific gene therapy for colorectal carcinoma.
基金Supported by the Medical Scientific Foundation of Jiangsu Province, No. H200147
文摘AIM: To evaluate the possible value of FasL in gastric cancer gene therapy by investigating the effects of FasL expression on human gastric cancer cell line. METHODS: An adenoviral vector encoding the full-length human FasL cDNA was constructed and used to infect a human gastric cancer (SGC-7901) cell line. FasL expression was confirmed by X-gal staining, flow cytometric analysis and RT-PCR. The effect of FasL on cell proliferation was determined by clonogenic assay, cytotoxicity was detected by MTT assay, and cell viability was measured by trypan blue exclusion. The therapeutic efficiency of Ad-FasL in vivo was investigated with a xenograft tumor model in nude mice. RESULTS: SGC-7901 cells infected with Ad-FasL showed increased expression of FasL, resulting in significantly decreased cell growth and colony-forming activity when compared with control adenovirus-infected cells. The cytotoxicity of anti-Fas antibody (CH-11) in gastric cancer cells was stronger than that of ActD (91±8 vs60±5,P<0.01), and the cytotoxicity of Ad-FasL was stronger than that of CH-11 (60±5 vs50±2, P<0.05). In addition, G1-phase arrest (67.75±0.39 vs 58.03±2.16, P<0.05) and apoptosis were observed in Ad-FasL-infected SGC-7901 cells, and the growth of SGC-7901 xenografts in nude mice was retarded after intra-tumoral injection with Ad-FasL (54% vs 0%,P<0.0001). CONCLUSION: Infection of human gastric carcinoma cells with Ad-FasL induces apoptosis, indicating that this target gene might be of potential value in gene therapy for gastric cancer.
文摘To examine the ability of intrastriatal gene transfer of vascular endothelial growth factor 165 mediated by adenoviral vector to rescue dopaminergic neurons in a rat model of Parkinson's disease (PD), we constructed recombinant replication-deficent adenoviral vectors carrying the gene of VEGF165 (Ad-VEGF), and injected Ad-VEGF (or Ad-LacZ and PBS as controls) into the striatum of rats 7 days after the lesion by 6-hydroxydopamine. The rat rotational behavior analysis and tyrosine hydroxylase (TH) immunohistochemistry were performed to assess the change of dopaminergic neurons. Our results showed that the rats receiving Ad-VEGF injection displayed a significant improvement in apomorphine-induced rotational behavior and a significant preservation of TH-positive neurons and fibers compared with control animals, It is concluded that intrastriatal gene transfer by Ad-VEGF may rescue the dopaminergic neurons from degeneration in a rat model of PD.
文摘Objective: To establish an efficient and safe gene transfer system mediated by retrovirus for gene marking and gene therapy of human leukemia. Method: The retroviral vector LXSN, containing the neomycin resistance (NeoR) gene, was transferred into amphotropic packaging cells GP+envAm12 by liposome transfection or by ecotropic retrovirus transduction. Amphotropic retrovirus in supernatants with higher titer was used to infect human leukemic cell lines NB4, U937, and THP-1. The efficiency of gene transfer was assayed on colonies formed by transduced K562 cells. Results: The titer of DOSPER directly transfected GP+envAm12 cells determined on NIH3T3 cells was 8.0×105 CFU/ml, while that of producer infected with retrovirus was 1.6×107 CFU/ml. Integration of NeoR gene into all leukemia cells was confirmed by polymerase chain reaction (PCR). Absence of replication-competent virus was proved by both nested PCR for env gene and marker gene rescue assay. Gene transfer with the efficiency as high as 93.3 to 100% in K562 cells was verified by seminested PCR for integrated NeoR gene on colonies after 7 days’ culture. Conclusion: The efficiency and safety of retrovirus mediated gene transfer system might provide an optimal system in gene therapy for leukemia or genetic diseases.
基金a grant from the ScientificCommittee of Hebei Province(No.982 76 110 1)
文摘Exogenous gene suture was used to achieve peripheral nerve anastomoses to probe into the feasibility that the sites of anastomoses of nerves directly transfer gene and thus enable gene to be expressed at the sites of anastomoses under the condition that perfect nerve anastomoses are ensured. PCMVβ plasmid containing cytomegalovirus promoter (CMV promoter) and Escherichia coli (E.coli) β Galactosidase (β Gal) structural gene (lacZ gene) was conducted. A soaked medical 8 0nylon suture was used to perform epineurial repair of rabbit sciatic nerve. In the control group a suture soaked in sucrose PBS was used, while in the experimental group a suture soaked in PCMVβ plasmid solution was applied. The sites of anastomoses of nerves by stages were taken out, and β Gal histochemical staining was performed and β Gal enzyme activity was assayed with 5 bromo 4 chloro 3 indolyl β D galactoside. Results showed that the sites of anastomoses of nerves were taken out 2 days, 7 days, 14 days and 30 days respectively after the operation. The β Gal histochemical stains at the sites of anastomoses showed no indigo positive cells at different stages in the control group, whereas displayed indigo positive cells in the experimental group. In the control group, no β Gal enzyme activity was detected at different stages after operation, but in the experimental group, β Gal enzyme activity could be detected from the 3rd day to the 30th day after operation. It was concluded that by using exogenous gene suture, exogenous gene could be transferred to the sites of peripheral nerve and expressed the exogenous gene expression products with bioactivity, which provided the feasibility of using gene therapy to accelerate the recovery of nerve function.
文摘Gene therapy has shown great potential to treat various diseases by repairing the abnormal gene function.However,a great challenge in bringing the nucleic acid formulations to the market is the safe and effective delivery to the specific tissues and cells.To be excited,the development of ionizable drug delivery systems(IDDSs)has promoted a great breakthrough as evidenced by the approval of the BNT162b2 vaccine for prevention of coronavirus disease 2019(COVID-19)in 2021.Compared with conventional cationic gene vectors,IDDSs can decrease the toxicity of carriers to cell membranes,and increase cellular uptake and endosomal escape of nucleic acids by their unique pH-responsive structures.Despite the progress,there remain necessary requirements for designing more efficient IDDSs for precise gene therapy.Herein,we systematically classify the IDDSs and summarize the characteristics and advantages of IDDSs in order to explore the underlying design mechanisms.The delivery mechanisms and therapeutic applications of IDDSs are comprehensively reviewed for the delivery of plasmid DNA(pDNA)and four kinds of RNA.In particular,organ selecting considerations and high-throughput screening are highlighted to explore efficiently multifunctional ionizable nanomaterials with superior gene delivery capacity.We anticipate providing references for researchers to rationally design more efficient and accurate targeted gene delivery systems in the future,and indicate ideas for developing next generation gene vectors.
基金supported by the National Natural Science Foundation of China(No.51472115)Double Firstclass Innovation Team of China Pharmaceutical University(CPU2018GY40).
文摘Genetic diseases seriously threaten human health and have always been one of the refractory conditions facing humanity.Currently,gene therapy drugs such as siRNA,shRNA,antisense oligonucleotide,CRISPR/Cas9 system,plasmid DNA and miRNA have shown great potential in biomedical applications.To avoid the degradation of gene therapy drugs in the body and effectively deliver them to target tissues,cells and organelles,the development of excellent drug delivery vehicles is of utmost importance.Viral vectors are the most widely used delivery vehicles for gene therapy in vivo and in vitro due to their high transfection efficiency and stable transgene expression.With the development of nanotechnology,novel nanocarriers are gradually replacing viral vectors,emerging superior performance.This review mainly illuminates the current widely used gene therapy drugs,summarizes the viral vectors and non-viral vectors that deliver gene therapy drugs,and sums up the application of gene therapy to treat genetic diseases.Additionally,the challenges and opportunities of the field are discussed from the perspective of developing an effective nano-delivery system.
基金ThisworkwassurpportedbyScientificCommitteeFoundationofShanghai (No 9941190 44 )
文摘OBJECTIVE: To determine the efficacy of adenovirus mediated suicide gene transduction combined with prodrug 5-fluorocytosine (5FC) as a therapeutic protocol for pancreatic cancer. METHODS: Cytosine Deaminase(CD) gene was cloned into pAdTrack-CMV-CD, pAdTrack-CMV-CD and pAdEasy-1 were recombined in bacteria. The newly recombined adenovirus (Ad)-CD containing green fluorescent protein (GFP) were packaged and propagated in 293 cells and purified by cesium chloride gradient centrifugation. Human pancreatic carcinoma cell line-Patu8988 was infected with this virus, then 5FC was added. XTT assay was used to estimate relative numbers of viable cells. In vivo model of pancreatic cancer was established by injecting 1.0 x 10(7) Patu8988 cells subcutaneously in Balb/c nude mice. When tumors were palpable, Ad-CD was injected into each tumor and 5FC was administered. RESULTS: Positive clones were selected using endonuclease to digest the recombinants and the concentration of viral liquids containing the CD gene was 2 x 10(11) pfu /ml. Significant cytotoxic activity as shown for 5FC in the CD gene transduced 8988 cell line, while little effect was found in the nontransduced pancreatic carcinoma cells. Antitumor effect was observed in Patu8988 xenograft nude mice with in situ CD gene transduction. CONCLUSIONS: CD gene mediated by adenovirus has high infectivity and may be useful for gene therapy in pancreatic carcinoma. These data demonstrate the use of an enzyme prodrug strategy in experimental pancreatic cancer.
文摘OBJECTIVE: To explore the inhibitory effect of human endostatin gene mediated by retroviral vector on the growth of human liver carcinoma. METHODS: A recombinant retroviral plasmid containing human endostatin gene and signal peptide was engineered and transferred into PA317 cells to produce retrovirus. Human liver carcinoma cells (SMMC7721) were infected with the above retrovirus to build a stable endostatin-transfected liver carcinoma cell line (SMMC-endo). The control liver carcinoma cell line (SMMC-pLncx) was developed in a similar way except that the plasmid was replaced by an empty retroviral vector. Immunohistochemistry and Western blot were used to test the expression and secretion of human endostatin. The biological activity of the expressed human endostatin was assessed by endothelial cell proliferation assay. The growth rates of SMMC-endo and control SMMC-pLncx cells in vivo and in vitro were also observed. RESULTS: The expression and secretion of human endostatin by endostatin-transfected SMMC-endo cells were confirmed by immunohistochemistry and Western blot. Compared with the control group, concentrated supernatant of SMMC-endo cells remarkably inhibited the proliferation of human umbilical vein endothelial cells by 48%, significantly higher than the inhibition by the control (10.2%; P
文摘OBJECTIVE: To specifically deliver the therapeutic gene to cancer cells and construct target retroviral vectors by inserting the single-chain variable antibody fragment into the retroviral envelope. METHODS: Single-chain antibody expression vector pET -20bScfv was constructed. Binding activity of the genetically engineered single-chain variable antibody fragment was verified by enzyme-linked immunosorbent assay (ELISA) and Western blot. At the same time, by means of polymerase chain reaction (PCR)-directed mutagenesis, the appropriate cloning site EcoT22/Sal was generated at the N-terminus of receptor-binding SU domain in the MoMLV env polypeptide. Then the single- chain antibody gene, encoding a functional antibody, was inserted into the cloning site. The Scfv-env fusion gene fragment was subcloned into CMV expression vector. The Lac-Z retrovirus that co-displayed the Scfv-env chimeric protein and wild-type env protein was produced by transfection of Psi 2 cells with retroviral plasmid and the fusion gene expressing plasmid.To confirm the specificity of the recombinant retrovirus, infection assays and competitive inhibition assays were performed. RESULTS: The results of ELISA and Western blot showed that the genetically engineered single-chain variable antibody fragment could bind to the SHG44 cells surface membrane antigen. Virus-binding assay, viral infection and competitive inhibition assays confirmed that the harvested virus efficiently bound to and infected SHG44 cancer cells expressing the relative membrane antigen specially via the recognition of the target antigen. CONCLUSION: These results imply that insertion of Scfv into the retroviral envelope can specifically deliver the interested gene into specific antigen-producing cancer cells.
文摘To investigate the feasibility and features of 3 catheter mediated approaches o f gene transfer into heart, including direct myocardial injection (DMI), coron ary artery perfusion (CAP), and intrapericardial cavity injection (ICI) Methods Fifteen dogs were used, and 0 3?ml (1×10 9 pfu) of an adenovirus (Adex1SR La cZ) was injected into the heart by 3 methods The dogs were killed 5 days foll owing injection, and gene expressions in heart and liver were evaluated by histochemical analysis Results The results showed that ① the CAP method was relatively less damaging and indu ced sparse LacZ expression in the myocardium, and the gene expression was also f ound in both vessels within the myocardium and liver; ② gene transfer by DMI res ulted in intense LacZ expression around the injection accompanied by a local inf lammatory response; ③ LacZ expression elicited by ICI was detected in either t he inner surface of the parietal pericardium or epicardial surface of the heart, and also in the myocardium underlying the visceral pericardium Conclusion Three catheter mediated methods of gene transfer into the heart may be used a nd a reasonable approach should be chosen according to purpose
文摘Gastric cancer is common in China [1-42],and its early diagnosis and treatment in advanced stage are difficult [31-50].In recent years ,gene study in cancer is a hotspot ,and great progress has been achieved [41-80] .Cancer gene therapy has shifted from the imagination into the laboratory and clinical trials.
文摘Gene therapy appears as a promising strategy to treatincurable diseases. In particular, combined gene therapy has shown improved therapeutic efficiency. Internal ribosome entry sites(IRESs), RNA elements naturally present in the 5' untranslated regions of a few m RNAs, constitute a powerful tool to co-express several genes of interest. IRESs are translational enhancers allowing the translational machinery to start protein synthesis by internal initiation. This feature allowed the design of multi-cistronic vectors expressing several genes from a single m RNA. IRESs exhibit tissue specificity, and drive translation in stress conditions when the global cell translation is blocked, which renders them useful for gene transfer in hypoxic conditions occurring in ischemic diseases and cancer. IRES-based viral and non viral vectors have been used successfully in preclinical and clinical assays of combined gene therapy and resulted in therapeutic benefits for various pathologies including cancers, cardiovascular diseases and degenerative diseases.
文摘Objective: To study the induction of sensitivity toganciclovir (GCV) or acyclovir (ACV) in humanhepatocellular carcinoma (HCC) cell line trans-ferred by an Epstein-Barr virus (EBV)-based repli-con expression vector carrying the herpes simplex vi-rus thymidine kinase (HSV-tk) gene, including kill-ing and "bystander" effect, and also the gene delive-ry procedure and route of gene therapy in vivo forHCC.Methods: Liposome-entrapped plasmid pDR2/tk wastransferred into HCC cells, and then different con-centrations of GCV or ACV were added. The trans-ferred cells were mixed with untransferred HCC cellsin different proportion and 200 μmol/L GCV wasthen added into each well. After 72 hours, all sam-ples were measured by MTT colorimetric assay. AnEBV-based plasmid eukarotic expression vector car-rying IL-2 cDNA was used. Three models of gene di-rect injection in the local liver, injection through theportal vein, and injection through the embolized he-patic artery were established in closed Wister rats.For each model, two subgroups, injected either na-ked plasmid DNA or lipofectin-plasmid complex wereincluded. The expression of the IL-2 gene was regu-larly examined immunohistochemically.Results: GCV or ACV could apparently kill thetransferred HCC cells at a concentration of 0. 2μmol/L. The inhibition rate was changed with dif-ferent drug concentrations. The "bystander" effectwas obviously induced at a transferred to untrans-ferred HCC cells ratio of 1:5. IL-2 gene expressionwas observed in liver cells of all animals on day 3,which reached peak within 3-7 days, and declined af-ter day 7. Injection of naked plasmid DNA throughthe hepatic artery plus embolization obtained a bestexpression.Conclusions: EBV-based vector is suitable for carry-ing suicide gene therapy for hepatocellular carcino-ma. Gene direct delivery in vivo combined with in-terventional surgery can be used to treat hepatocellu-lar carcinoma.
基金Supported by a faculty research grant of Yonsei University College of Medicine for 2002,No.2002-06
文摘AIM:rAAV mediated endostatin gene therapy has been examined as a new method for treating cancer.However, a sustained and high protein delivery is required to achieve the desired therapeutic effects.We evaluated the impact of topoisomerase inhibitors in rAAV delivered endostatin gene therapy in a liver tumor model. METHODS:rAAV containing endostatin expression cassettes were transduced into hepatoma cell lines.To test whether the topoisomerase inhibitor pretreatment increased the expression of endostatin,Western blotting and ELISA were performed.The biologic activity of endostatin was confirmed by endothelial cell proliferation and tube formation assays. The anti-tumor effects of the rAAV-endostatin vector combined with a topoisomerase inhibitor,etoposide,were evaluated in a mouse liver tumor model. RESULTS:Topoisomerase inhibitors,including camptothecin and etoposide,were found to increase the endostatin exPression level in vitro.The over-expressed endostatin, as a result of pretreatment with a topoisomerase inhibitor, was also biologically active.In animal experiments,the combined therapy of topoisomerase inhibitor,etoposide with the rAAV-endostatin vector had the best tumor- suppressive effect and tumor foci were barely observed in livers of the treated mice.Pretreatment with an etoposide increased the level of endostatin in the liver and serum of rAAV-endostatin treated mice.Finally,the mice treated With rAAV-endostatin in combination with etoposide showed the longest survival among the experimental models. CONCLUSION:rAAV delivered endostatin gene therapy in combination with a topoisomerase inhibitor pretreatment is an effective modality for anticancer gene therapy.
基金MT was funded by the Leistungsorientierte Mittelvergabe(LOM)scholarship offered by the medical faculty of Magdeburg and the Deutscher Akademischer Austauschdienst(DAAD).
文摘Apoptosis,a key mechanism of programmed cell death,is triggered by caspase-3 protein and lowering its levels with gene therapy may rescue cell death after central nervous system damage.We developed a novel,non-viral gene therapy to block caspase-3 gene expression using small interfering RNA(siRNA)delivered by polybutylcyanoacrylate nanoparticles(CaspNPs).In vitro CaspNPs significantly blocked caspase-3 protein expression in C6 cells,and when injected intraocularly in vivo,CaspNPs lowered retinal capsase-3 immunofluorescence by 57.9%in rats with optic nerve crush.Longitudinal,repeated retinal ganglion cell counts using confocal neuroimaging showed that post-traumatic cell loss after intraocular CaspNPs injection was only 36.1%versus 63.4%in lesioned controls.Because non-viral gene therapy with siRNA-nanoparticles can selectively silence caspace-3 gene expression and block apoptosis in post-mitotic neurons,siRNA delivery with nanoparticles may be promising for neuroprotection or restoration of central visual system damage and other neurological disorders.The animal study procedures were approved by the German National Act on the use of experimental animals(Ethic Committee Referat Verbraucherschutz,Veterinärangelegenheiten;Landesverwaltungsamt Sachsen-Anhalt,Halle,Germany,#IMP/G/01-1150/12 and#IMP/G/01-1469/17).
文摘This narrative review highlights routes of ocular drug delivery for age-related macular degeneration(AMD).AMD is the leading cause of irreversible blindness in industrialized countries and accounts for 8.7%of blindness worldwide.Advanced AMD can be classified into two subtypes:late-stage dry AMD[known as geographic atrophy(GA)]and neovascular AMD(nAMD).GA is often bilateral and results from progressive and irreversible loss of photoreceptors and areas of the retinal pigment epithelium.Wet AMD is characterized by angiogenesis from the choroid to the normally avascular regions underneath the retinal pigment epithelium(RPE)or retina,a process known as choroidal neovascularization(CNV).Various targeted therapeutic options are currently available to reduce the progression rate and maintain vision in patients with nAMD.Intravitreal delivery of anti-VEGF protein treatments to halt CNV is currently the gold-standard of care for nAMD.Subretinal and suprachoroidal delivery approaches are also being explored for gene and molecular therapies.Advancements in nanotechnology and biomaterials have also led to the development of microscopic drug delivery systems,including hydrogels,microparticles,nanoparticles,implants,and liposomes.Gene therapy and stem cell therapy has recently emerged as a potential candidate treatment modality for AMD and other retinal degenerations.New drug targets and modalities have stimulated exciting developments in ocular drug delivery with the promise of greater efficacy and durability of AMD treatment.