Objective To construct recombinant lentiviral vectors for gene delivery of the glial cell line-derived neurotropnic factor (GDNF), and evaluate the neuroprotective effect of GDNF on lactacystin-damaged PC12 cells by...Objective To construct recombinant lentiviral vectors for gene delivery of the glial cell line-derived neurotropnic factor (GDNF), and evaluate the neuroprotective effect of GDNF on lactacystin-damaged PC12 cells by transfecting it into bone marrow stromal cells (BMSCs). Methods pLenti6/V5-GDNF plasmid was set up by double restriction enzyme digestion and ligation, and then the plasmid was transformed into Top10 cells. Purified pLenti6/V5-GDNF plasmids from the positive clones and the packaging mixture were cotransfected to the 293FT packaging cell line by Lipofectamine2000 to produce lentivirus, then the concentrated virus was transduced to BMSCs. Overexpression of GDNF in BMSCs was tested by RT-PCR, ELISA and immunocytochemistry, and its neuroprotection for lactacystin-damaged PC12 cells was evaluated by MTT assay. Results Virus stock of GDNF was harvested with the titer of 5.6×10^5 TU/mL. After tmnsduction, GDNF-BMSCs successfully secreted GDNF to supematant with nigher concentration (800 pg/mL) than BMSCs did (less than 100 pg/mL). The supematant of GDNF-BMSCs could significantly alleviate the damage of PC12 cells induced by lactacystin (10 μmol/L). Conclusion Overexpression of lentivirus-mediated GDNF in the BMSCs cells can effectively protect PC12 cells from the injury by the proteasome inhibitor.展开更多
Objective: To construct Bifidobacterium Infantis/CD targeting gene therapy system. Methods: CD gene was amplified from E. Coli K12λ using PCR method, pGEX-1LamdaT plasmid and CD gene were digested with dual restric...Objective: To construct Bifidobacterium Infantis/CD targeting gene therapy system. Methods: CD gene was amplified from E. Coli K12λ using PCR method, pGEX-1LamdaT plasmid and CD gene were digested with dual restriction endonucleas of EcoR Ⅰ and BamH Ⅰ and two segments of 4.9 kb and 1.3 kb were obtained. T4 DNA ligase was added to these two segments to make a recombinant CD/pGEX-1LamdaT plasmid. Then the recombinant plasmid was transfected into Bifidobacterium Infantis by electroporation. The recombinant plasmid was extracted from the positively transfected Bifidobacterium Infantis and digested with dual restriction endonucleases. Then the size of digested fragments was detected and sequencing of the gene segment inserted in extracted recombinant plasmid was performed according to the method of Sanger dideoxynucleotide triphosphate chain termination. Results: 6.2 kb recombinant plasmid was obtained from the positively transfected bacterial colony of Bifidobacterium Infantis. After being digested with dual restriction endonucleases, two segments of approximate 4.9 kb and 1.3 kb were gained from the extracted recombinant plasmid, which were equal to the size of pGEX-1LamdaT plasmid and CD gene, respectively. The full length and sequence of nucleotide acid of the inserted gene in extracted recombinant plasmid was completely identical to the CD gene. Conclusion: The foreign gene, CD gene was correctly inserted into pGEX-1LambdaT plasmid and transferred into Bifidobacterium Infantis. Bifidobacterium Infantis/CD targeting gene therapy system was successfully constructed.展开更多
[ Objective] The study was to clone HN and F genes from GX1 strain of goose paramyxovirus and analyze their sequences. [ Method] According to the full nucleotide sequence of GPV-SF02 strain of goose paramyxovirus, two...[ Objective] The study was to clone HN and F genes from GX1 strain of goose paramyxovirus and analyze their sequences. [ Method] According to the full nucleotide sequence of GPV-SF02 strain of goose paramyxovirus, two pairs of pdmers were designed to amplify the HN and F genes from GX1 strain of goose paramyxovirus isolated from diseased goose in Guangxi Zhuang Autonomous Region; the amplified products were ligated into pMD18-T vector and sequenced. [ Result ] HN and F genes of this strain tested were 1 716 and 1 662 bp in full nucleotide length, respectively; both showed the homologues of about 97.3% with GPV- SF02 strain, of 80.3% -97.5% with strains LaSota, F48E9 and JS, of just 84.8% with Miyadera strain. [ Conclusion] The results show that isolated strain BX1 matches to virulent APMV-1 strain, belonging to genotype Ⅶ of APMV-1 strain.展开更多
ONYX-015 is an attractive therapeutic adenovirus for cancer because it can selectively replicate in tumor cells and kill them. To date, clinical trials of this adenovirus have demonstrated marked safety but not potent...ONYX-015 is an attractive therapeutic adenovirus for cancer because it can selectively replicate in tumor cells and kill them. To date, clinical trials of this adenovirus have demonstrated marked safety but not potent enough when it was used alone. In this paper, we put forward a novel concept of Gene-ViroTherapy strategy and in this way, we constructed an armed therapeutic oncolytic adenovirus system, ZD55-gene, which is not only deleted of ElB 55-kD gene similar to ONYX-015, but also armed with foreign antitumor gene. ZD55-gene exhibited similar cytopathic effects and replication kinetics to that of ONYX-015 in vitro. Importantly, the carried gene is expressed and the expression level can increase with the replication of virus. Consequently, a significant antitumoral efficacy was observed when ZD55-CD/5-FU was used as an example in nude mice with subcutaneous human SW620 colon cancer. Our data demonstrated that ZD55-gene, which utilizing the Gene-ViroTherapy strategy, is more efficacious than each individual component in vivo.展开更多
RNA interference (RNAi) is an evolutionally conserved gene silencing mechanism present in a variety of eukaryotic species. RNAi uses short double-stranded RNA (dsRNA) to trigger degradation or translation repression o...RNA interference (RNAi) is an evolutionally conserved gene silencing mechanism present in a variety of eukaryotic species. RNAi uses short double-stranded RNA (dsRNA) to trigger degradation or translation repression of homologous RNA targets in a sequence-specific manner. This system can be induced effectively in vitro and in vivo by direct application of small interfering RNAs (siRNAs), or by expression of short hairpin RNA (shRNA) with non-viral and viral vectors. To date, RNAi has been extensively used as a novel and effective tool for functional genomic studies, and has displayed great potential in treating human diseases, including human genetic and acquired disorders such as cancer and viral infections. In the present review, we focus on the recent development in the use of RNAi in the prevention and treatment of viral infections. The mechanisms, strategies, hurdles and prospects of employing RNAi in the pharmaceutical industry are also discussed.展开更多
Gene and viral therapies for cancer have shown some therapeutic effects, but there has been a lack of real breakthrough. To achieve the goal of complete elimination of tumor xenograft in animal models, we have develop...Gene and viral therapies for cancer have shown some therapeutic effects, but there has been a lack of real breakthrough. To achieve the goal of complete elimination of tumor xenograft in animal models, we have developed a new strategy called Targeting Gene-Virotherapy of Cancer, which aims to combine the advantages of both gene therapy and virotherapy. This new strategy has produced stronger anti-tumor effects than either gene or viral therapy alone. A tumorspecific replicative adenovirus vector, designated as ZD55, was constructed by deletion of the 55kDa E1B region of adenovirus. The resulting viral construct not only retains a similar function to ONYX-015 by specifically targeting p53 negative tumors, but also allows for the insertion of various therapeutic genes to form appropriate ZD55 derivatives due to the newly introduced cloning site, a task not feasible with the original ONYX-015 virus. We showed that the anti-tumor effect of one such derivative, ZD55-IL-24, is at least 100 times more potent than that of either ZD55 virotherapy or Ad-IL-24 gene therapy. Nevertheless, complete elimination of tumor mass by the use of ZD55-1L-24 was only observed in some but not all mice, indicating that one therapeutic gene was not sufficient to "cure" these mice. When genes with complementary or synergetic effects were separately cloned into the ZD55 vector and used in combination (designated as the Dual Gene Therapy strategy), much better results were obtained; and it was possible to achieve complete elimination of all the xenograft tumor masses in all mice if two suitable genes were chosen. More comprehensive studies based on this new strategy will likely lead to a protocol for clinical trial. Finally, the concept of Double Controlled Targeting Virus-Dual Gene Therapy for cancer treatment, and the implication of the recent progress in cancer stem cells are also discussed.展开更多
Our purpose is to completely elimination of xenograft tumor in animal tumor model in order to work out a protocal for the cure of patient. Gene therapy and viral therapy for cancer have got some therapeutic effects, b...Our purpose is to completely elimination of xenograft tumor in animal tumor model in order to work out a protocal for the cure of patient. Gene therapy and viral therapy for cancer have got some therapeutic effects, but both have no great breakthrough. Therefore, we worked out a new strategy called Targeting Gene-Virotherapy of Cancer which is a combination of the advantage of gene therapy and virotherapy. This new strategy has stronger antitumor effect than either of them alone. A tumor specific replicative adenovirus vector ZD55 (E1B 55KD deleted Adv.) which is similar to ONYX-015 in targeting fuction but significant different in construction was produced and various single therapeutic gene was inserted into ZD55. Now such a conception as Targeting Gene-Virotherapy of Cancer was raised and systemically studied before, although there are some works on ONYX-015-tk, -cd or cd/-tk etc. separately. The antitumor effect of ZD55-Gene (for example IL-24 gene) is much better than ZD55 (virotherapy) alone and hundred fold high than that ofAd-IL-24 (gene therapy) alone. ZD55-IL-24 was in preclinal studying in the ZD55-IL-24 therapy, completely elimination of tumor mass was occurred in some mice but not in all mice, that means one gene was not effictive enough to eliminate all the tumor mass in all mice. Therefore two genes with compensative or synergetic effect were inserted into ZD55 sepearately and used in combinction. This strategy was called Targeting Dual Gene-Virotherapy of Cancer (with PCT patent). Then much better results were obtained and all the xenograft tumor masses were completely eliminated in all mice, if two suitable genes were chosen. On the basis of the initiation of two gene results, it was thought about that using two tumors promoter to control the virus vector will be better for the targeting effect and the safty of the drugs. Then double tumor controlled virus vector harboring two genes for cancer therapy was worked out. Better results have been obtained and another patent has been applied. This antitumor strategy could be used to kill all the tumor cells completely in all mice with minimum damage to normal cells.展开更多
Gene therapy is a new and promising approach which opens a new door to the treatment of human diseases. By direct transfer of genetic materials to the target cells, it could exert functions on the level of genes and m...Gene therapy is a new and promising approach which opens a new door to the treatment of human diseases. By direct transfer of genetic materials to the target cells, it could exert functions on the level of genes and molecules. It is hoped to be widely used in the treatment of liver disease, especially hepatic tumors by using different vectors encoding the aim gene for anti-tumor activity by activating primary and adaptive immunity, inhibiting oncogene and angiogenesis. Despite the huge curative potential shown in animal models and some pilot clinical trials, gene therapy has been under fierce discussion since its birth in academia and the public domain because of its unexpected side effects and ethical problems. There are other challenges arising from the technique itself like vector design, administration route test and standard protocol exploration. How well we respond will decide the fate of gene therapy clinical medical practice.展开更多
AIM: To investigate the prevalence of hepatitis C virus (HCV) genotypes in Serbia and Montenegro and their influence on some clinical characteristics in patients with chronic HCV infection. METHODS: A total of 164...AIM: To investigate the prevalence of hepatitis C virus (HCV) genotypes in Serbia and Montenegro and their influence on some clinical characteristics in patients with chronic HCV infection. METHODS: A total of 164 patients was investigated. Complete history, route of infection, assessment of alcohol consumption, an abdominal ultrasound, standard biochemical tests and liver biopsy were done. Gene sequencing of 5' NTR type-specific PCR or commercial kits was performed for HCV genotyping and subtyping. The SPSS for Windows (version 10.0) was used for univariate regression analysis with further multivariate analysis. RESULTS: The genotypes 1, 2, 3, 4, 1b3a and 1b4 were present in 57.9%, 3.7%, 23.2%, 6.7%, 6.7% and 1.8% of the patients, respectively. The genotype 1 (mainly the subtype 1b) was found to be independent of age in subjects older than 40 years, high viral load, more severe necro-inflammatory activity, advanced stage of fibrosis, and absence of intravenous drug abuse. The genotype 3a was associated with intravenous drug abuse and the age below 40. Multivariate analysis demonstrated age over 40 and intravenous drug abuse as the positive predictive factors for the genotypes lb and 3a, respectively.CONCLUSION: In Serbia and Montenegro, the genotypes 1b and 3a predominate in patients with chronic HCV infection. The subtype lb is characteristic of older patients, while the genotype 3a is common in drug abusers. Association of the subtype lb with advanced liver disease, higher viral load and histological activity suggests earlier infection with this genotype and eventually its increased pathogenicity.展开更多
Gastric cancer is one of the most common tumors worldwide. The therapeutic outcome of conventional therapies is inefficient. Thus, new therapeutic strategies are urgently needed. Gene therapy is a promising molecular ...Gastric cancer is one of the most common tumors worldwide. The therapeutic outcome of conventional therapies is inefficient. Thus, new therapeutic strategies are urgently needed. Gene therapy is a promising molecular alternative in the treatment of gastric cancer, including the replacement of defective tumor suppressor genes, the inactivation of oncogenes, the introduction of suicide genes, genetic immunotherapy, anti-angiogenetic gene therapy, and virotherapy. Improved molecular biological techniques and a better understanding of gastric carcinogenesis have allowed us to validate a variety of genes as molecular targets for gene therapy. This review provides an update of the new developments in cancer gene therapy, new principles, techniques, strategies and vector systems, and shows how they may be applied in the treatment of gastric cancer.展开更多
Transcatheter arterial chemoembolization (TACE) has become the standard treatment for unresectable hepatocellular carcinoma (HCC). But this method has some shortages. p53 gene, which was found to be mutant in many hum...Transcatheter arterial chemoembolization (TACE) has become the standard treatment for unresectable hepatocellular carcinoma (HCC). But this method has some shortages. p53 gene, which was found to be mutant in many human tumors, has been proved with broadspectrum anti-tumor effects. We reported a 23-year-old patient with recurrent HCC after irregular hepatectomy. The p53 gene was applied to this patient. We injected percutaneously and infused transcatheterally p53 gene (Gendicine, Shenzhen Sibiono Bentech, China) into his recurrent nodules in liver respectively and 4 d later, the patient received TACE therapy. In the 2 mo follow-up, the patient was in good clinical condition with normal liver function and no recurrence was identified. The case report proposed that recurrent HCC could be successfully treated with p53 gene therapy combining TACE.展开更多
Gastric cancer is one of the most common malignancies worldwide. With current therapeutic approaches the prognosis of gastric cancer is very poor, as gastric cancer accounts for the second most common cause of death i...Gastric cancer is one of the most common malignancies worldwide. With current therapeutic approaches the prognosis of gastric cancer is very poor, as gastric cancer accounts for the second most common cause of death in cancer related deaths. Gastric cancer like almost all other cancers has a molecular genetic basis which relies on disruption in normal cellular regulatory mechanisms regarding cell growth, apoptosis and cell division. Thus novel therapeutic approaches such as gene therapy promise to become the alternative choice of treatment in gastric cancer. In gene therapy, suicide genes, tumor suppressor genes and anti-angiogenesis genes among many others are introduced to cancer cells via vectors. Some of the vectors widely used in gene therapy are Adenoviral vectors. This review provides an update of the new developments in adenoviral cancer gene therapy including strategies for inducing apoptosis, inhibiting metastasis and targeting the cancer cells.展开更多
Recent developments in tumor immunology and biotechnology have made cancer gene therapy and immunotherapy feasible. The current efforts for cancer gene therapy mainly focus on using immunogenes, chemogenes and tumor s...Recent developments in tumor immunology and biotechnology have made cancer gene therapy and immunotherapy feasible. The current efforts for cancer gene therapy mainly focus on using immunogenes, chemogenes and tumor suppressor genes. Central to all these therapies is the development of efficient vectors for gene therapy. By far, adenovirus (AdV)-mediated gene therapy is one of the most promising approaches, as has confirmed by studies relating to animal tumor models and clinical trials. Dendritic cells (DCs) are highly efficient, specialized antigen-presenting cells, and DC- based tumor vaccines are regarded as having much potential in cancer immunotherapy. Vaccination with DCs pulsed with tumor peptides, lysates, or RNA, or loaded with apoptotic/necrotic tumor cells, or engineered to express certain cytokines or chemokines could induce significant antitumor cytotoxic T lymphocyte (CTL) responses and antitumor immunity. Although both AdV-mediated gene therapy and DC vaccine can both stimulate antitumor immune responses, their therapeutic efficiency has been limited to generation of prophylactic antitumor immunity against re-challenge with the parental tumor cells or to growth inhibition of small tumors. However, this approach has been unsuccessful in combating well-established tumors in animal models. Therefore, a major strategic goal of current cancer immunotherapy has become the development of novel therapeutic strategies that can combat well-established tumors, thus resembling real clinical practice since a good proportion of cancer patients generally present with significant disease. In this paper, we review the recent progress in AdV-mediated cancer gene therapy and DC-based cancer vaccines, and discuss combined immunotherapy including gene therapy and DC vaccines. We underscore the fact that combined therapy may have some advantages in combating well-established tumors vis-a-vis either modality administered as a monotherapy.展开更多
AIM: To evaluate the therapeutic efficiency of replicative adenovirus CNHK300 targeted in telomerase-positive hepatoceUular carcinoma.METHODS: CNHK300, ONYX-015 (55 kDa protein deleted adenovirus) and wtAd5 (wild...AIM: To evaluate the therapeutic efficiency of replicative adenovirus CNHK300 targeted in telomerase-positive hepatoceUular carcinoma.METHODS: CNHK300, ONYX-015 (55 kDa protein deleted adenovirus) and wtAd5 (wild type adenovirus 5) were compared, and virus proliferation assay, cell viability assay, Western blot and fluorescence microscopy were used to evaluate the proliferation and cytolysis selectivity of CNHK300.RESULTS: The replicative multiples in Hep3B and HepG Ⅰ after 48 Ⅱ of CNHK300 proliferation were 40625 and 65326 fold, respectively, similar to that of wtAd5.. However, CNHK300 exhibited attenuated replicative ability in normal fibroblast cell line BJ. CNHK300 could lyse hepatocellular carcinoma cells at a low multiplicity of infection (MOI), but could not affect growth of normal cells even at a high MOI.CONCLUSION: CNHK300 is a cancer-selective replication-competent adenovirus which can cause oncolysis of liver cancer cells as well as wtAd5 (wild type adenovirus 5), but had severely attenuated replicative and cytolytic ability in normal cells. This novel strategy of cancer treatment offers a promising treatment platform.展开更多
AIM: To investigate whether the recombinant adenovirus induces the TNF-α-mediated apoptosis in vivo. METHODS: Human hepatocarcinoma cell line (HepG2) cells were transfected into BALB/c nude mice, and the tumor gr...AIM: To investigate whether the recombinant adenovirus induces the TNF-α-mediated apoptosis in vivo. METHODS: Human hepatocarcinoma cell line (HepG2) cells were transfected into BALB/c nude mice, and the tumor growth curve was drawn. We analyzed apoptosis in HepG2 cells by TUNEL, HE staining and electron microscopy. RESULTS: AdIκBαM was expressed stably and efficiently in HepG2 and could not be degraded by induction of TNF-α. Tumor growth in mice could be reduced remarkably if treated by AdIκBαM plus TNF-α. There was apoptosis of 〉 70% of cells treated with AdIκBαM plus TNF-α and about 50% of cells treated with AdIκBαM. In contrast, there was few cell apoptosis in HepG2 cells treated with phosphate buffered saline and AdIκBαM. HepG2 cells in mice also exhibited a high level of apoptosis after in vivo injection with AdIκBαM. The tumor growth curve indicated the tumor transfected with AdIκBαM could be restrained. CONCLUSION: AdIκBαM gene therapy greatly enhances apoptosis due to inhibition of an NF-κB-mediated antiapoptosis signaling pathway.展开更多
AIM: To determine the gene expression profile data for the whole liver during development of dimethylni-trosamine (DMN)-induced hepatic fibrosis.METHODS: Marker genes were identified for different types of hepatic cel...AIM: To determine the gene expression profile data for the whole liver during development of dimethylni-trosamine (DMN)-induced hepatic fibrosis.METHODS: Marker genes were identified for different types of hepatic cells, including hepatic stellate cells (HSCs), Kupffer cells (including other inflammatory cells), and hepatocytes, using independent temporal DNA microarray data obtained from isolated hepatic cells. RESULTS: The cell-type analysis of gene expression gave several key results and led to formation of three hypotheses: (1) changes in the expression of HSC-specific marker genes during fibrosis were similar to gene expression data in in vitro cultured HSCs, suggesting a major role of the self-activating characteristics of HSCs in formation of fibrosis; (2) expression of mast cell-specific marker genes reached a peak during liver fibrosis, suggesting a possible role of mast cells in formation of fibrosis; and (3) abnormal expression of hepatocyte-specific marker genes was found across several metabolic pathways during fibrosis, including sulfur-containing amino acid metabolism, fatty acid metabolism, and drug metabolism, suggesting a mechanistic relationship between these abnormalities and symptoms of liver fibrosis. CONCLUSION: Analysis of marker genes for specific hepatic cell types can identify the key aspects of fibro-genesis. Sequential activation of inflammatory cells and the self-supporting properties of HSCs play an important role in development of fibrosis.展开更多
AIM: To clone and characterize the porcine aquaporins (AQPs) in the gastrointestinal system.METHODS: A PCR-based cloning strategy and RACE were used to clone full-length AQP coding sequence from reversely transcri...AIM: To clone and characterize the porcine aquaporins (AQPs) in the gastrointestinal system.METHODS: A PCR-based cloning strategy and RACE were used to clone full-length AQP coding sequence from reversely transcribed pig liver cDNA. Stopped-flow light scattering and a YFP-based fluorescence method were used to measure the osmotic water permeability of erythrocytes and the stably transfected CHO cells. RT-PCR, Northern blot, and immunohistochemistry were used to determine the gastrointestinal expression and localization of cloned AQPs. Protein expression in transfected cells and red blood cells was analyzed by Western blot.RESULTS: An 813 bp cDNA encoding a 271 amino acid porcine aquaporin (designated pAQP1) was cloned from liver mRNA (pAQP1 has a 93% identity with human AQP1 and contains two NPA motifs conserved in AQP family, one consensus sequence for N-linked glycosylation, and one mercury-sensitive site at cysteine 191). RT-PCR analysis revealed extensive expression of pAQP1 mRNA in porcine digestive glands and gut. Northern blot showed a single 3.0 kb transcript in selected digestive organs, pAQP1 protein was localized at central lacteals of the small intestine, microvessles of salivary glands, as well as epithelium of intrahepatic bile ducts by immunoperoxydase. High osmotic water permeability that is inhibitable by HgCI2 was detected in porcine erythrocytes and CHO cells stably transfected with pAQP1 cDNA. Immunoblot analysis of porcine erythrocytes and pAQP-transfected CHO cells revealed an unglycosylated 28 ku band and larger glycosylated proteins.CONCLUSION: pAQP1 is the first porcine aquaporin that can be molecularly identified so far. The broad distribution of pAQP1 in epithelium and endothelium of porcine digestive organs may suggest an important role of channel-mediated water transport in fluid secretion/absorption as well as in digestive function and pathophysiology of the gastrointestinal system.展开更多
Objective To investigate the methylation status of LRP15 gene in acute leukemia (AL) patients and its role in the tumorigenesis. Methods The methylation of LRP15 promoter and first exon of bone marrow mononuclear ce...Objective To investigate the methylation status of LRP15 gene in acute leukemia (AL) patients and its role in the tumorigenesis. Methods The methylation of LRP15 promoter and first exon of bone marrow mononuclear cells in 73 patients with AL, 10 with chronic leukemia (CL), 9 with hematological benign diseases, and 20 healthy transplantation donors was analyzed by using methylation specific polymerase chain reaction. The methylation of LRP15 gene promoter and first exon in COS7, K562, and HL60 cell lines was also assayed. Resuits No LRP15 gene promoter methylation was detected in COS7 cell line. LRP15 gene promoter was methylated in K562 and HL60 cell lines. No deletion of LRP15 gene was detected in all samples. In nearly all French-American-British leukemia subtypes, we found that frequency of LRP15 methylation in adult patients with AL was 71.23% ( 52/73 ). There was no detectable methylation in any of the 20 healthy donors and 8 chronic myeloid leukemia patients. The difference in frequency of LRP15 methylation between AL patients and healthy donors or CL patients ( 10.00%, 1/10) was significant (P 〈0.01 ). Hypermethylation of LRP15 gene was found in 57.14% (16/28) of newly diagnosed AL patients, 83.33% of relapsed AL patients respectively, which was significantly different ( P 〈 0.05 ). We also demonstrated LRP15 methylation in 55.56% (5/9) adults with benign hematological diseases. Conclusions LRP15 methylation changes are common abnormalities in leukemia. LRP15 is postulated to be a tumor suppressor gene.展开更多
Gene therapy offers a new approach for treatment of cancer. Transfer of genes encoding immunostimulatory cytokines has been used with remarkable success to eliminate cancer in animals. However, clinical trials in pati...Gene therapy offers a new approach for treatment of cancer. Transfer of genes encoding immunostimulatory cytokines has been used with remarkable success to eliminate cancer in animals. However, clinical trials in patients with this strategy had limited efficacy. Therefore, improvement ofgene transfer vector system is necessary. A hybrid viral vector, consisting of SFV replicon with either murine IL-12 or reporter LacZ gene, was constructed. This hybrid vector showed specificity and high level of expression in HCC both in vitro and in vivo. In a rat orthotropic liver tumor model, treatment of established tumors by the hybrid vector with raiL- 12 gene resulted in a strong anti-tumor activity without accompanying toxicity. Subsequently, a helper-dependent adenovirus vectors containing a mifepristone (RU486) inducible system was constructed for controlled and liver-specific expression of human interleukin 12 (hIL- 12) (HD-Ad/RUhIL- 12) and mouse IL-12 (mIL-12) (HD-Ad/RUmIL-12). Data showed that high and sustained serum levels of hlL-12 could be attained by continuing administration of RU486 every 12 or 24 h. Repetitive induction ofhlL-12 could be obtained over, at least, a period of 48 weeks after a single injection of HD-Ad/RUhlL-12. Treatment of liver metastases with of HD-Ad/RUmIL- 12 plus RU846 resulted in complete tumor regression in all animals. Then, different cytokine genes were inserted into conditional replicative adenoviruses vectors (also called oncolytic adenovirus). Replication ofadenovirus in tumor cells would kill tumor cells and release viruses, which infect surrounding tumor cells. The combination of cytopathic effect by oncolytic adenovirus and biological effect of transgene would exert strong antitumor activity. These new types of vectors may provide a potent and safe tool for cancer gene therapy.展开更多
基金This work was supported by the Natural Science Foundation of Shanghai Municipality(No.03ZR14016).
文摘Objective To construct recombinant lentiviral vectors for gene delivery of the glial cell line-derived neurotropnic factor (GDNF), and evaluate the neuroprotective effect of GDNF on lactacystin-damaged PC12 cells by transfecting it into bone marrow stromal cells (BMSCs). Methods pLenti6/V5-GDNF plasmid was set up by double restriction enzyme digestion and ligation, and then the plasmid was transformed into Top10 cells. Purified pLenti6/V5-GDNF plasmids from the positive clones and the packaging mixture were cotransfected to the 293FT packaging cell line by Lipofectamine2000 to produce lentivirus, then the concentrated virus was transduced to BMSCs. Overexpression of GDNF in BMSCs was tested by RT-PCR, ELISA and immunocytochemistry, and its neuroprotection for lactacystin-damaged PC12 cells was evaluated by MTT assay. Results Virus stock of GDNF was harvested with the titer of 5.6×10^5 TU/mL. After tmnsduction, GDNF-BMSCs successfully secreted GDNF to supematant with nigher concentration (800 pg/mL) than BMSCs did (less than 100 pg/mL). The supematant of GDNF-BMSCs could significantly alleviate the damage of PC12 cells induced by lactacystin (10 μmol/L). Conclusion Overexpression of lentivirus-mediated GDNF in the BMSCs cells can effectively protect PC12 cells from the injury by the proteasome inhibitor.
文摘Objective: To construct Bifidobacterium Infantis/CD targeting gene therapy system. Methods: CD gene was amplified from E. Coli K12λ using PCR method, pGEX-1LamdaT plasmid and CD gene were digested with dual restriction endonucleas of EcoR Ⅰ and BamH Ⅰ and two segments of 4.9 kb and 1.3 kb were obtained. T4 DNA ligase was added to these two segments to make a recombinant CD/pGEX-1LamdaT plasmid. Then the recombinant plasmid was transfected into Bifidobacterium Infantis by electroporation. The recombinant plasmid was extracted from the positively transfected Bifidobacterium Infantis and digested with dual restriction endonucleases. Then the size of digested fragments was detected and sequencing of the gene segment inserted in extracted recombinant plasmid was performed according to the method of Sanger dideoxynucleotide triphosphate chain termination. Results: 6.2 kb recombinant plasmid was obtained from the positively transfected bacterial colony of Bifidobacterium Infantis. After being digested with dual restriction endonucleases, two segments of approximate 4.9 kb and 1.3 kb were gained from the extracted recombinant plasmid, which were equal to the size of pGEX-1LamdaT plasmid and CD gene, respectively. The full length and sequence of nucleotide acid of the inserted gene in extracted recombinant plasmid was completely identical to the CD gene. Conclusion: The foreign gene, CD gene was correctly inserted into pGEX-1LambdaT plasmid and transferred into Bifidobacterium Infantis. Bifidobacterium Infantis/CD targeting gene therapy system was successfully constructed.
基金Supported by the Development Program for Guangxi Science andTechnology(0719004-3G)~~
文摘[ Objective] The study was to clone HN and F genes from GX1 strain of goose paramyxovirus and analyze their sequences. [ Method] According to the full nucleotide sequence of GPV-SF02 strain of goose paramyxovirus, two pairs of pdmers were designed to amplify the HN and F genes from GX1 strain of goose paramyxovirus isolated from diseased goose in Guangxi Zhuang Autonomous Region; the amplified products were ligated into pMD18-T vector and sequenced. [ Result ] HN and F genes of this strain tested were 1 716 and 1 662 bp in full nucleotide length, respectively; both showed the homologues of about 97.3% with GPV- SF02 strain, of 80.3% -97.5% with strains LaSota, F48E9 and JS, of just 84.8% with Miyadera strain. [ Conclusion] The results show that isolated strain BX1 matches to virulent APMV-1 strain, belonging to genotype Ⅶ of APMV-1 strain.
基金supported by the Key Project of the Chinese Academy of Sciences(No.KSCX2-3-06)the National Natural Science Foundation of China(No.30120160823)the Chinese National“863”High Tech Project Foundation grant(No.2002AA216021).
文摘ONYX-015 is an attractive therapeutic adenovirus for cancer because it can selectively replicate in tumor cells and kill them. To date, clinical trials of this adenovirus have demonstrated marked safety but not potent enough when it was used alone. In this paper, we put forward a novel concept of Gene-ViroTherapy strategy and in this way, we constructed an armed therapeutic oncolytic adenovirus system, ZD55-gene, which is not only deleted of ElB 55-kD gene similar to ONYX-015, but also armed with foreign antitumor gene. ZD55-gene exhibited similar cytopathic effects and replication kinetics to that of ONYX-015 in vitro. Importantly, the carried gene is expressed and the expression level can increase with the replication of virus. Consequently, a significant antitumoral efficacy was observed when ZD55-CD/5-FU was used as an example in nude mice with subcutaneous human SW620 colon cancer. Our data demonstrated that ZD55-gene, which utilizing the Gene-ViroTherapy strategy, is more efficacious than each individual component in vivo.
基金RFCID, No 01030152, RGC, CUHK4428/06M, ITF ITS091/03 of Hong Kong Government, and Faculty Direct Fund of the Chinese University of Hong Kong
文摘RNA interference (RNAi) is an evolutionally conserved gene silencing mechanism present in a variety of eukaryotic species. RNAi uses short double-stranded RNA (dsRNA) to trigger degradation or translation repression of homologous RNA targets in a sequence-specific manner. This system can be induced effectively in vitro and in vivo by direct application of small interfering RNAs (siRNAs), or by expression of short hairpin RNA (shRNA) with non-viral and viral vectors. To date, RNAi has been extensively used as a novel and effective tool for functional genomic studies, and has displayed great potential in treating human diseases, including human genetic and acquired disorders such as cancer and viral infections. In the present review, we focus on the recent development in the use of RNAi in the prevention and treatment of viral infections. The mechanisms, strategies, hurdles and prospects of employing RNAi in the pharmaceutical industry are also discussed.
文摘Gene and viral therapies for cancer have shown some therapeutic effects, but there has been a lack of real breakthrough. To achieve the goal of complete elimination of tumor xenograft in animal models, we have developed a new strategy called Targeting Gene-Virotherapy of Cancer, which aims to combine the advantages of both gene therapy and virotherapy. This new strategy has produced stronger anti-tumor effects than either gene or viral therapy alone. A tumorspecific replicative adenovirus vector, designated as ZD55, was constructed by deletion of the 55kDa E1B region of adenovirus. The resulting viral construct not only retains a similar function to ONYX-015 by specifically targeting p53 negative tumors, but also allows for the insertion of various therapeutic genes to form appropriate ZD55 derivatives due to the newly introduced cloning site, a task not feasible with the original ONYX-015 virus. We showed that the anti-tumor effect of one such derivative, ZD55-IL-24, is at least 100 times more potent than that of either ZD55 virotherapy or Ad-IL-24 gene therapy. Nevertheless, complete elimination of tumor mass by the use of ZD55-1L-24 was only observed in some but not all mice, indicating that one therapeutic gene was not sufficient to "cure" these mice. When genes with complementary or synergetic effects were separately cloned into the ZD55 vector and used in combination (designated as the Dual Gene Therapy strategy), much better results were obtained; and it was possible to achieve complete elimination of all the xenograft tumor masses in all mice if two suitable genes were chosen. More comprehensive studies based on this new strategy will likely lead to a protocol for clinical trial. Finally, the concept of Double Controlled Targeting Virus-Dual Gene Therapy for cancer treatment, and the implication of the recent progress in cancer stem cells are also discussed.
文摘Our purpose is to completely elimination of xenograft tumor in animal tumor model in order to work out a protocal for the cure of patient. Gene therapy and viral therapy for cancer have got some therapeutic effects, but both have no great breakthrough. Therefore, we worked out a new strategy called Targeting Gene-Virotherapy of Cancer which is a combination of the advantage of gene therapy and virotherapy. This new strategy has stronger antitumor effect than either of them alone. A tumor specific replicative adenovirus vector ZD55 (E1B 55KD deleted Adv.) which is similar to ONYX-015 in targeting fuction but significant different in construction was produced and various single therapeutic gene was inserted into ZD55. Now such a conception as Targeting Gene-Virotherapy of Cancer was raised and systemically studied before, although there are some works on ONYX-015-tk, -cd or cd/-tk etc. separately. The antitumor effect of ZD55-Gene (for example IL-24 gene) is much better than ZD55 (virotherapy) alone and hundred fold high than that ofAd-IL-24 (gene therapy) alone. ZD55-IL-24 was in preclinal studying in the ZD55-IL-24 therapy, completely elimination of tumor mass was occurred in some mice but not in all mice, that means one gene was not effictive enough to eliminate all the tumor mass in all mice. Therefore two genes with compensative or synergetic effect were inserted into ZD55 sepearately and used in combinction. This strategy was called Targeting Dual Gene-Virotherapy of Cancer (with PCT patent). Then much better results were obtained and all the xenograft tumor masses were completely eliminated in all mice, if two suitable genes were chosen. On the basis of the initiation of two gene results, it was thought about that using two tumors promoter to control the virus vector will be better for the targeting effect and the safty of the drugs. Then double tumor controlled virus vector harboring two genes for cancer therapy was worked out. Better results have been obtained and another patent has been applied. This antitumor strategy could be used to kill all the tumor cells completely in all mice with minimum damage to normal cells.
文摘Gene therapy is a new and promising approach which opens a new door to the treatment of human diseases. By direct transfer of genetic materials to the target cells, it could exert functions on the level of genes and molecules. It is hoped to be widely used in the treatment of liver disease, especially hepatic tumors by using different vectors encoding the aim gene for anti-tumor activity by activating primary and adaptive immunity, inhibiting oncogene and angiogenesis. Despite the huge curative potential shown in animal models and some pilot clinical trials, gene therapy has been under fierce discussion since its birth in academia and the public domain because of its unexpected side effects and ethical problems. There are other challenges arising from the technique itself like vector design, administration route test and standard protocol exploration. How well we respond will decide the fate of gene therapy clinical medical practice.
文摘AIM: To investigate the prevalence of hepatitis C virus (HCV) genotypes in Serbia and Montenegro and their influence on some clinical characteristics in patients with chronic HCV infection. METHODS: A total of 164 patients was investigated. Complete history, route of infection, assessment of alcohol consumption, an abdominal ultrasound, standard biochemical tests and liver biopsy were done. Gene sequencing of 5' NTR type-specific PCR or commercial kits was performed for HCV genotyping and subtyping. The SPSS for Windows (version 10.0) was used for univariate regression analysis with further multivariate analysis. RESULTS: The genotypes 1, 2, 3, 4, 1b3a and 1b4 were present in 57.9%, 3.7%, 23.2%, 6.7%, 6.7% and 1.8% of the patients, respectively. The genotype 1 (mainly the subtype 1b) was found to be independent of age in subjects older than 40 years, high viral load, more severe necro-inflammatory activity, advanced stage of fibrosis, and absence of intravenous drug abuse. The genotype 3a was associated with intravenous drug abuse and the age below 40. Multivariate analysis demonstrated age over 40 and intravenous drug abuse as the positive predictive factors for the genotypes lb and 3a, respectively.CONCLUSION: In Serbia and Montenegro, the genotypes 1b and 3a predominate in patients with chronic HCV infection. The subtype lb is characteristic of older patients, while the genotype 3a is common in drug abusers. Association of the subtype lb with advanced liver disease, higher viral load and histological activity suggests earlier infection with this genotype and eventually its increased pathogenicity.
文摘Gastric cancer is one of the most common tumors worldwide. The therapeutic outcome of conventional therapies is inefficient. Thus, new therapeutic strategies are urgently needed. Gene therapy is a promising molecular alternative in the treatment of gastric cancer, including the replacement of defective tumor suppressor genes, the inactivation of oncogenes, the introduction of suicide genes, genetic immunotherapy, anti-angiogenetic gene therapy, and virotherapy. Improved molecular biological techniques and a better understanding of gastric carcinogenesis have allowed us to validate a variety of genes as molecular targets for gene therapy. This review provides an update of the new developments in cancer gene therapy, new principles, techniques, strategies and vector systems, and shows how they may be applied in the treatment of gastric cancer.
文摘Transcatheter arterial chemoembolization (TACE) has become the standard treatment for unresectable hepatocellular carcinoma (HCC). But this method has some shortages. p53 gene, which was found to be mutant in many human tumors, has been proved with broadspectrum anti-tumor effects. We reported a 23-year-old patient with recurrent HCC after irregular hepatectomy. The p53 gene was applied to this patient. We injected percutaneously and infused transcatheterally p53 gene (Gendicine, Shenzhen Sibiono Bentech, China) into his recurrent nodules in liver respectively and 4 d later, the patient received TACE therapy. In the 2 mo follow-up, the patient was in good clinical condition with normal liver function and no recurrence was identified. The case report proposed that recurrent HCC could be successfully treated with p53 gene therapy combining TACE.
文摘Gastric cancer is one of the most common malignancies worldwide. With current therapeutic approaches the prognosis of gastric cancer is very poor, as gastric cancer accounts for the second most common cause of death in cancer related deaths. Gastric cancer like almost all other cancers has a molecular genetic basis which relies on disruption in normal cellular regulatory mechanisms regarding cell growth, apoptosis and cell division. Thus novel therapeutic approaches such as gene therapy promise to become the alternative choice of treatment in gastric cancer. In gene therapy, suicide genes, tumor suppressor genes and anti-angiogenesis genes among many others are introduced to cancer cells via vectors. Some of the vectors widely used in gene therapy are Adenoviral vectors. This review provides an update of the new developments in adenoviral cancer gene therapy including strategies for inducing apoptosis, inhibiting metastasis and targeting the cancer cells.
文摘Recent developments in tumor immunology and biotechnology have made cancer gene therapy and immunotherapy feasible. The current efforts for cancer gene therapy mainly focus on using immunogenes, chemogenes and tumor suppressor genes. Central to all these therapies is the development of efficient vectors for gene therapy. By far, adenovirus (AdV)-mediated gene therapy is one of the most promising approaches, as has confirmed by studies relating to animal tumor models and clinical trials. Dendritic cells (DCs) are highly efficient, specialized antigen-presenting cells, and DC- based tumor vaccines are regarded as having much potential in cancer immunotherapy. Vaccination with DCs pulsed with tumor peptides, lysates, or RNA, or loaded with apoptotic/necrotic tumor cells, or engineered to express certain cytokines or chemokines could induce significant antitumor cytotoxic T lymphocyte (CTL) responses and antitumor immunity. Although both AdV-mediated gene therapy and DC vaccine can both stimulate antitumor immune responses, their therapeutic efficiency has been limited to generation of prophylactic antitumor immunity against re-challenge with the parental tumor cells or to growth inhibition of small tumors. However, this approach has been unsuccessful in combating well-established tumors in animal models. Therefore, a major strategic goal of current cancer immunotherapy has become the development of novel therapeutic strategies that can combat well-established tumors, thus resembling real clinical practice since a good proportion of cancer patients generally present with significant disease. In this paper, we review the recent progress in AdV-mediated cancer gene therapy and DC-based cancer vaccines, and discuss combined immunotherapy including gene therapy and DC vaccines. We underscore the fact that combined therapy may have some advantages in combating well-established tumors vis-a-vis either modality administered as a monotherapy.
基金International Cooperative Key Project of the National Natural Science Foundation of China, No. 30120160824the State 863 High Technology R&D Project of China, No. 2001AA217031
文摘AIM: To evaluate the therapeutic efficiency of replicative adenovirus CNHK300 targeted in telomerase-positive hepatoceUular carcinoma.METHODS: CNHK300, ONYX-015 (55 kDa protein deleted adenovirus) and wtAd5 (wild type adenovirus 5) were compared, and virus proliferation assay, cell viability assay, Western blot and fluorescence microscopy were used to evaluate the proliferation and cytolysis selectivity of CNHK300.RESULTS: The replicative multiples in Hep3B and HepG Ⅰ after 48 Ⅱ of CNHK300 proliferation were 40625 and 65326 fold, respectively, similar to that of wtAd5.. However, CNHK300 exhibited attenuated replicative ability in normal fibroblast cell line BJ. CNHK300 could lyse hepatocellular carcinoma cells at a low multiplicity of infection (MOI), but could not affect growth of normal cells even at a high MOI.CONCLUSION: CNHK300 is a cancer-selective replication-competent adenovirus which can cause oncolysis of liver cancer cells as well as wtAd5 (wild type adenovirus 5), but had severely attenuated replicative and cytolytic ability in normal cells. This novel strategy of cancer treatment offers a promising treatment platform.
基金Supported by the Foundation of Hi-tech Research and Develop-ment Program of China (863 Program), No. 2001AA217121Co-fi rst-author: Li-Ping Jia
文摘AIM: To investigate whether the recombinant adenovirus induces the TNF-α-mediated apoptosis in vivo. METHODS: Human hepatocarcinoma cell line (HepG2) cells were transfected into BALB/c nude mice, and the tumor growth curve was drawn. We analyzed apoptosis in HepG2 cells by TUNEL, HE staining and electron microscopy. RESULTS: AdIκBαM was expressed stably and efficiently in HepG2 and could not be degraded by induction of TNF-α. Tumor growth in mice could be reduced remarkably if treated by AdIκBαM plus TNF-α. There was apoptosis of 〉 70% of cells treated with AdIκBαM plus TNF-α and about 50% of cells treated with AdIκBαM. In contrast, there was few cell apoptosis in HepG2 cells treated with phosphate buffered saline and AdIκBαM. HepG2 cells in mice also exhibited a high level of apoptosis after in vivo injection with AdIκBαM. The tumor growth curve indicated the tumor transfected with AdIκBαM could be restrained. CONCLUSION: AdIκBαM gene therapy greatly enhances apoptosis due to inhibition of an NF-κB-mediated antiapoptosis signaling pathway.
文摘AIM: To determine the gene expression profile data for the whole liver during development of dimethylni-trosamine (DMN)-induced hepatic fibrosis.METHODS: Marker genes were identified for different types of hepatic cells, including hepatic stellate cells (HSCs), Kupffer cells (including other inflammatory cells), and hepatocytes, using independent temporal DNA microarray data obtained from isolated hepatic cells. RESULTS: The cell-type analysis of gene expression gave several key results and led to formation of three hypotheses: (1) changes in the expression of HSC-specific marker genes during fibrosis were similar to gene expression data in in vitro cultured HSCs, suggesting a major role of the self-activating characteristics of HSCs in formation of fibrosis; (2) expression of mast cell-specific marker genes reached a peak during liver fibrosis, suggesting a possible role of mast cells in formation of fibrosis; and (3) abnormal expression of hepatocyte-specific marker genes was found across several metabolic pathways during fibrosis, including sulfur-containing amino acid metabolism, fatty acid metabolism, and drug metabolism, suggesting a mechanistic relationship between these abnormalities and symptoms of liver fibrosis. CONCLUSION: Analysis of marker genes for specific hepatic cell types can identify the key aspects of fibro-genesis. Sequential activation of inflammatory cells and the self-supporting properties of HSCs play an important role in development of fibrosis.
基金Supported by National Natural Science Foundation for Distinguished Young Scholars,No.30325011National Natural Science Foundation of China,No.30470405Distinguished Young Scholar Foundation of Jilin Province,No.20030112.
文摘AIM: To clone and characterize the porcine aquaporins (AQPs) in the gastrointestinal system.METHODS: A PCR-based cloning strategy and RACE were used to clone full-length AQP coding sequence from reversely transcribed pig liver cDNA. Stopped-flow light scattering and a YFP-based fluorescence method were used to measure the osmotic water permeability of erythrocytes and the stably transfected CHO cells. RT-PCR, Northern blot, and immunohistochemistry were used to determine the gastrointestinal expression and localization of cloned AQPs. Protein expression in transfected cells and red blood cells was analyzed by Western blot.RESULTS: An 813 bp cDNA encoding a 271 amino acid porcine aquaporin (designated pAQP1) was cloned from liver mRNA (pAQP1 has a 93% identity with human AQP1 and contains two NPA motifs conserved in AQP family, one consensus sequence for N-linked glycosylation, and one mercury-sensitive site at cysteine 191). RT-PCR analysis revealed extensive expression of pAQP1 mRNA in porcine digestive glands and gut. Northern blot showed a single 3.0 kb transcript in selected digestive organs, pAQP1 protein was localized at central lacteals of the small intestine, microvessles of salivary glands, as well as epithelium of intrahepatic bile ducts by immunoperoxydase. High osmotic water permeability that is inhibitable by HgCI2 was detected in porcine erythrocytes and CHO cells stably transfected with pAQP1 cDNA. Immunoblot analysis of porcine erythrocytes and pAQP-transfected CHO cells revealed an unglycosylated 28 ku band and larger glycosylated proteins.CONCLUSION: pAQP1 is the first porcine aquaporin that can be molecularly identified so far. The broad distribution of pAQP1 in epithelium and endothelium of porcine digestive organs may suggest an important role of channel-mediated water transport in fluid secretion/absorption as well as in digestive function and pathophysiology of the gastrointestinal system.
基金Supported by National Natural Science Foundation (39970318)Millitary Medical Research Foundation (01J007)National Basic Research Program (2005CB522400).
文摘Objective To investigate the methylation status of LRP15 gene in acute leukemia (AL) patients and its role in the tumorigenesis. Methods The methylation of LRP15 promoter and first exon of bone marrow mononuclear cells in 73 patients with AL, 10 with chronic leukemia (CL), 9 with hematological benign diseases, and 20 healthy transplantation donors was analyzed by using methylation specific polymerase chain reaction. The methylation of LRP15 gene promoter and first exon in COS7, K562, and HL60 cell lines was also assayed. Resuits No LRP15 gene promoter methylation was detected in COS7 cell line. LRP15 gene promoter was methylated in K562 and HL60 cell lines. No deletion of LRP15 gene was detected in all samples. In nearly all French-American-British leukemia subtypes, we found that frequency of LRP15 methylation in adult patients with AL was 71.23% ( 52/73 ). There was no detectable methylation in any of the 20 healthy donors and 8 chronic myeloid leukemia patients. The difference in frequency of LRP15 methylation between AL patients and healthy donors or CL patients ( 10.00%, 1/10) was significant (P 〈0.01 ). Hypermethylation of LRP15 gene was found in 57.14% (16/28) of newly diagnosed AL patients, 83.33% of relapsed AL patients respectively, which was significantly different ( P 〈 0.05 ). We also demonstrated LRP15 methylation in 55.56% (5/9) adults with benign hematological diseases. Conclusions LRP15 methylation changes are common abnormalities in leukemia. LRP15 is postulated to be a tumor suppressor gene.
文摘Gene therapy offers a new approach for treatment of cancer. Transfer of genes encoding immunostimulatory cytokines has been used with remarkable success to eliminate cancer in animals. However, clinical trials in patients with this strategy had limited efficacy. Therefore, improvement ofgene transfer vector system is necessary. A hybrid viral vector, consisting of SFV replicon with either murine IL-12 or reporter LacZ gene, was constructed. This hybrid vector showed specificity and high level of expression in HCC both in vitro and in vivo. In a rat orthotropic liver tumor model, treatment of established tumors by the hybrid vector with raiL- 12 gene resulted in a strong anti-tumor activity without accompanying toxicity. Subsequently, a helper-dependent adenovirus vectors containing a mifepristone (RU486) inducible system was constructed for controlled and liver-specific expression of human interleukin 12 (hIL- 12) (HD-Ad/RUhIL- 12) and mouse IL-12 (mIL-12) (HD-Ad/RUmIL-12). Data showed that high and sustained serum levels of hlL-12 could be attained by continuing administration of RU486 every 12 or 24 h. Repetitive induction ofhlL-12 could be obtained over, at least, a period of 48 weeks after a single injection of HD-Ad/RUhlL-12. Treatment of liver metastases with of HD-Ad/RUmIL- 12 plus RU846 resulted in complete tumor regression in all animals. Then, different cytokine genes were inserted into conditional replicative adenoviruses vectors (also called oncolytic adenovirus). Replication ofadenovirus in tumor cells would kill tumor cells and release viruses, which infect surrounding tumor cells. The combination of cytopathic effect by oncolytic adenovirus and biological effect of transgene would exert strong antitumor activity. These new types of vectors may provide a potent and safe tool for cancer gene therapy.