• Tuberculosis and Respiratory Diseases
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• v.51 no.2
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• pp.135-146
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• 2001

Background : One of the important mechanisms responsible for a tumor escaping the immune response is an absence of the tumor associated antigen (TAA) on the cancer cell surface. To overcome this, combination gene therapy using a herpes simplex thymidine kinase (HSTK) gene, prototype of drug sensitizing gene, was conducted to enhance T AA release by cell destruction, as well as the cytokine genes for immune cell attraction. Methods : We investigated whether or not transduction with the adenovirus-HSTK (Ad-HSTK) enhanced the sensitivity of Lewis lung carcinoma (LLC) to ganciclovir (GCV) and induced a bystander effect. A Tumor vaccine trial was performed using LLC with ad-HSTK$\pm$ad-GM-CSF$\pm$ad-IL-2 to determine if they exhibit some antitumor effect on established lung cancer xenografts. Results : LLC with ad-HSTK revealed a much higher sensitivity to ganciclovir (GCV). LLC transduced with ad-HSTK and/or ad-IL-2, ad-GM-CSF showed a lower in vivo tumorigenicity. In the treatment experiment, vaccination with LLC transduced with ad-HSTK, ad-IL-2, or ad-GM-CSF alone modestly suppressed the growth of an established tumor. Combined transduction with HSTK and GM-CSF induced stronger growth suppression of a established lung cancer, while HSTK and IL-2 combination transduction did not have any antitumor effect on individual transduction. Vaccination with LLC-HSTK-GM-CSF increased the infiltration of dendritic cells in the spleen. Conclusion : It was concluded that a tumor vaccine transduced with HSTK and GM-CSF induces strong antitumor immunity by activating the dendritic cells.

• 대한두경부종양학회:학술대회논문집
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• 2001.05a
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• pp.71-71
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• 2001

• Journal of Industrial Technology
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• v.42 no.1
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• pp.29-36
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• 2022

The CRISPR system has revolutionized gene editing field. Cas9-mediated gene editing such as Indel induction or HDR enable targeted gene disruption or precise correction of mutation. Moreover, CRISPR-based new editing tools have been developed such as base editors. In this review, we focus on gene editing in human pluripotent stem cells, which is principal technique for gene correction therapy and disease modeling. Pluripotent stem cell-specific drug YM155 enabled selection of target gene-edited pluripotent stem cells. Also, we discussed base editing for treatment of congenital retina disease. Adenine base editor delivery as RNP form provide an approach for genetic disease treatment with safe and precise in vivo gene correction.

• Journal of Pharmaceutical Investigation
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• v.32 no.3
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• pp.153-159
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• 2002

Gene therapy is fundamentally a sophisticated drug delivery technology to cure a disease by the transfer of genetic material to modify living cells. In other words, the gene is used as a therapeutic drug much like a chemical compound is employed in chemotherapy. Currently almost 600 clinical trials are underway worldwide since the first clinical trials carried out in 1990 to treat adenosine deaminase deficiency using retroviral vectors. Despite the great progress still is there no gene therapy product being approved as a new drug. This is partly due to a lack of an ideal gene delivery system that is safe and can provide stable, optimal level production of the therapeutic proteins in the cell. This review covers the current status of several different biological and physico-chemical agents that are being developed as gene delivery vehicles. Although gene therapy promises great hopes toward the cure of a broad spectrum of genetic and acquired diseases, the success of gene therapy heavily asks for the development of vector systems for safe and efficient application in humans.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.5
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• pp.2309-2312
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• 2014

Esophageal squamous cell carcinoma (ESCC) is the most common histologic subtype of esophageal cancer and is characterized by a poor prognosis. Determining gene changes in ESCCs should improve understanding of putative risk factors and provide potential targets for therapy. We sequenced about 55 million pair-end reads from a pair of adjacent normal and ESCC samples to identify the gene expression level and gene fusion. Sanger sequencing was used to verify the result. About 17 thousand genes were expressed in the tissues, of which approximately 2400 demonstrated significant differences between tumor and adjacent non tumor tissue. GO and KEGG pathway analysis revealed that many of these genes were associated with cellular adherence and movement, simulation responses and immune responses. Notably we identified and validated one fusion gene, HLA-E and HLA-B, located 1 MB apart. We also identified thousands of remarkably expressed transcripts. In conclusion, a novel fusion gene HLA-E and HLA-B was identified in ESCC via whole transcriptome sequencing, which would be a biomarker for ESCC diagnosis and target for therapy, shedding new light for better understanding of ESCC tumorigenesis.

• Journal of Photoscience
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• v.9 no.3
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• pp.41-43
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• 2002

PDT-mediated cyototoxicity basically depends on the penetrated light-dose into the tumor tissue. This limits the efficiency of PDT to the superficial tumor region typically less than 1 cm. The localized photochemical generation of reactive oxygen species, including singlet oxygen is known to increase expression of assortment of early response genes including heat shock protein. In order to increase PDT cytotoxicity in the treatment of solid tumor, it is desirable to combine PDT with other therapeutic effects. In this preliminary study we evaluated enhanced cytotoxicity from the PDT-mediated expression of thymidine kinase in a transfected tumor cell line. Two types of photo sensitizers, a hematoporphyrin derivative(Photogem, Russia) and aluminium sulphonated phthalocyanine(Photosense, Russia) were used to evaluate the overexpression of hsp-70 in PDT-treated cell. Transient increase of hsp-70 was observed at 6-8 hrs later following irradiation in the photosense-treated cell whereas it was not observed in Photogem-treated cell. In the presence of ganciclovia, transfected cell showed a 17％ increase in the cytotoxicity compared to the PDT only cell.

• Journal of Life Science
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• v.18 no.10
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• pp.1395-1399
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• 2008

We have recently reported the PRC1 promoter as a promoter candidate to control expression of transcriptionally targeted genes for breast cancer gene therapy. We tested whether the PRC1 promoter could be also applied for the lung cancer gene therapy. In the transient transfection assay with naked plasmids containing the luciferase fused to the PRC1 promoter, the promoter showed little activity in the normal lung cell line, MRC5. However, in the lung cancer A549 cells, PRC1 showed approximately 30-fold activation which was similar to the survivin promoter, the gene whose promoter has been already reportedas a candidate for the gene therapy of lung cancer. In viral systems, the PRC1 promoter showed approximately 75% and 66% of transcriptional activity compared to the CMV promoter in the adeno-associated virus (AAV) and the adenovirus (AV) systems, respectively. However, the PRC1 promoter in either AAV or AV showed approximately 20% activity compared to the CMV promoter in the normal lung cells. In addition, human lung tumor xenograft mice showed that the PRC1 promoter activity was as strong as the CMV activity in vivo. Taken together, these results suggested that PRC1 might be a potential promoter candidate for transcriptionally targeted lung cancer gene therapy.

• Journal of Korean Neurosurgical Society
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• v.29 no.4
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• pp.471-476
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• 2000

Objective : p16/INK4a, a kind of tumor suppressor genes, encodes a specific inhibitor of the cyclin D-dependent kinases CDK4 and CDK6. This prevents the association of CDK4 with cyclin D1, and subsequently inhibits phosphorylation of retinoblastoma tumor suppressor protein(pRb), thus preventing exit from the G1 phase. According to previous reports, over 50% of glioma tissue and 80% of glioma cell lines have been demonstrated inactivation of p16/INK4a gene. The purpose of this study was to determine whether recombinant adenovirus-p16 virus is a suitable candidate for gene replacement therapy in cases of glioma. Methods : Three human glioma cell lines(U251MG, U87MG and U373MG) that express mutant p16 protein were used. Replication-deficient adenovirus was utilized as an expression vector to transfer exogenous p16 cDNA into the cells ; control cells were infected with the Ad-${\beta}$-gal expressing ${\beta}$-galactosidase. To monitor gene transfer and the expression of exogenous genes, we used Western Blotting analysis. Flow cytometry studies of cellular DNA content were performed to determine the cell cycle phenotype of the glioma cells before and after treatment. Results : We showed here that restoration of p16/INK4a expression in p16 negative U87MG, U251MG and partially deleted U373MG by Ad-CMV-p16 induced growth suppression in vitro. Flow cytometric study revealed that Ad-CMV-p16 infected U87MG cells were arrested during the G0-G1 phase of the cell cycle. Expression of p16 transferred by Ad-CMV-p16 in glioma cells was highly efficient and maintained for more than seven days. Conclusions : Our results suggest that Ad-CMV-p16 gene therapy strategy is potentially useful and warrants further clinical investigation for the treatment of gliomas.

• IMMUNE NETWORK
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• v.1 no.1
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• pp.45-52
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• 2001

Background: Many types of cancer become resistant to current chemotherapeutic and radiotherapeutic intervention. To overcome this situation application of gene therapy by the introduction of suicide genes followed by their prodrugs may be promising. A viral enzyme, Herpes simplex thymidine kinase (HSV-tk), which converts ganciclovir from an inactive prodrug to a cytotoxic agent by phosphorylation, are being actively investigated for use in gene therapy for cancer. The purpose of this study was to determine whether combining prodrug-activating gene therapy and irradiation might result in enhanced antitumor effects. Methods: The HSV-tk gene was cloned into the retroviral vector, pLXSN and established the clones producing retroviruses carrying the HSV-tk gene. The carcinoma cell line, HCT116 and Huh-7 were transduced with high-titer recombinant retroviruses. These cell lines were treated with ganciclovir before or after irradiation for the defining combinational effect of suicide gene therapy and radiotherapy. Results: The titers of cloned PA3 17 amphotropic retroviruses ranged from 4 to 6 X $10^6CFU/ml4$. After selectional periods, the expression of HSV-tk was confirmed by reverse-transcriptase polymerase chain reaction (RT-PCR). The growth of cells expressing HSV-tk was inhibited as increase of GCV dose after 48 hr and the growth inhibitory effect of GCV was much higher after 72 hr. When the cells transduced with HSV-tk gene were exposed to radiation, the growth inhibitory effect of GCV was significantly increased, as compared with non-transduced parental cells. Conclusions: The results suggest that the addition of HSV-tk gene therapy to standard radiation therapy may improve the effectiveness of treatment for solid tumors.

• IMMUNE NETWORK
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• v.9 no.4
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• pp.115-121
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• 2009

Natural killer (NK) cells play key roles in innate and adaptive immune defenses. NK cell responses are mediated by two major mechanisms: the direct cytolysis of target cells, and immune regulation by production of various cytokines. Many previous reports show that the complex NK cell activation process requires de novo gene expression regulated at both transcriptional and post-transcriptional levels. Specialized un-translated regions (UTR) of mRNAs are the main mechanisms of post-transcriptional regulation. Analysis of posttranscriptional regulation is needed to clearly understand NK cell biology and, furthermore, harness the power of NK cells for therapeutic aims. This review summarizes the current understanding of mRNA metabolism during NK cell activation, focusing primarily on post-transcriptional regulation.