• Asian Pacific Journal of Cancer Prevention
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• v.13 no.3
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• pp.781-784
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• 2012

The aim of this study was to evaluate the effect of the adenovirus-mediated double suicide gene (CD/TK) for selective killing of gastric cancer cells. Gastric cancer cells SCG7901 and normal gastric epithelial cell lines were infected by adenoviruses Ad-survivin/GFP and Ad-survivin/CD/TK. GFP expression and CD-TK were detected by fluorescence microscopy and reverse transcriptase polymerase chain reaction (RT-PCR), respectively. After treatment of the infected cells with the pro-drugs ganciclovir (GCV) and/or 5-FC, the cell growth status was evaluated by methyl thiazolyl tetrazolium assay. Cell cycle changes were detected using flow cytometry. In nude mice bearing human gastric cancer, the recombinant adenovirus vector was injected directly into the tumor followed by an intraperitoneal injection of GCV and/or 5-FC. The subsequent tumor growth was then observed. The GFP gene driven by survivin could be expressed within the gastric cancer line SCG7901, but not in normal gastric epithelial cells. RT-PCR demonstrated the presence of the CD/TK gene product in the infected SCG7901 cells, but not in the infected normal gastric epithelial cells. The infected gastric cancer SCG7901, but not the gastric cells, was highly sensitive to the pro-drugs. The CD/TK fusion gene system showed significantly greater efficiency than either of the single suicide genes in killing the target cells (P<0.01). Treatment of the infected cells with the pro-drugs resulted in increased cell percentage in G0-Gl phase and decreased percentage in S phase. In nude mice bearing SCG7901 cells, treatment with the double suicide gene system significantly inhibited tumor growth, showing much stronger effects than either of the single suicide genes (P<0.01). The adenovirus-mediated CD/TK double suicide gene driven by survivin promoter combined with GCV an 5-FC treatment could be an effective therapy against experimental gastric cancer with much greater efficacy than the single suicide gene CD/TK combined with GCV or 5-FC.

• Nutrition Research and Practice
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• v.13 no.1
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• pp.58-63
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• 2019

BACKGROUND/OBJECTIVES: Telomeres are located at the chromosomal ends and progressively shortened during each cell cycle. Telomerase, which is regulated by hTERT and c-MYC, maintains telomeric DNA sequences. Especially, telomerase is active in cancer and stem cells to maintain telomere length for replicative immortality. Recently we reported that walnut phenolic extract (WPE) can reduce cell viability in a colon cancer stem cell (CSC) model. We, therefore, investigated the effect of WPE on telomere maintenance in the same model. MATERIALS AND METHODS: $CD133^+CD44^+$ cells from HCT116, a human colon cancer cell line, were sorted by Fluorescence-activated cell sorting (FACS) and treated with WPE at the concentrations of 0, 10, 20, and $40{\mu}g/mL$ for 6 days. Telomere lengths were assessed by quantitative real-time PCR (qRT-PCR) using telomere specific primers and DNA extracted from the cells, which was further adjusted with single-copy gene and reference DNA ($ddC_t$). Telomerase activity was also measured by qRT-PCR after incubating the PCR mixture with cell protein extracts, which was adjusted with reference DNA ($dC_t$). Transcriptions of hTERT and c-MYC were determined using conventional RT-PCR. RESULTS: Telomere length of WPE-treated cells was significantly decreased in a dose-dependent manner ($5.16{\pm}0.13$ at $0{\mu}g/mL$, $4.79{\pm}0.12$ at $10{\mu}g/mL$, $3.24{\pm}0.08$ at $20{\mu}g/mL$ and $3.99{\pm}0.09$ at $40{\mu}g/mL$; P = 0.0276). Telomerase activities concurrently decreased with telomere length ($1.47{\pm}0.04$, $1.09{\pm}0.01$, $0.76{\pm}0.08$, and $0.88{\pm}0.06$; P = 0.0067). There was a positive correlation between telomere length and telomerase activity (r = 0.9090; P < 0.0001). Transcriptions of both hTERT and c-MYC were also significantly decreased in the same manner. CONCLUSION: In the present cell culture model, WPE reduced telomere maintenance, which may provide a mechanistic link to the effect of walnuts on the viability of colon CSCs.

• Proceedings of the KSAR Conference
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• 2002.06a
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• pp.69-69
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• 2002

To investigate the effects of two antioxidants, aesculeitin and taurine, expression of apoptosis related genes and antioxidant enzyme gene in preimplantation Hanwoo embryos was determined by modified semi-quantitative single cell RT-PCR. Hanwoo embryos derived from in vitro maturation /in vitro fertilization were cultured in 5% CO₂ and 5% O₂ in CR₁aa medium at 37℃. Aesculeitin and taurine were added to medium at concentration of l㎍/㎖ and 2.5mM, respectively. (omitted)

• Korean Journal of Animal Reproduction
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• v.27 no.3
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• pp.225-231
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• 2003

Transgenic mice containing Diphtheria Toxin-A (DT-A) gene fused to proximal lck promoter sequences was used for analysis of DT-A gene expression and thymocyte development. The diphtheria toxin gene was expressed in thymus, spleen and liver of transgenic mice confirmed by RT-PCR and Northern blotting. A FACS analysis with thymocyte cell surface antigens antibodies (CD4 and CD8) showed that the number of peripheral mature single positive thymocytes ($CD4^{+}\;and\;CD8^{+}$ cells) T-cells was severely reduced in transgenic mice compared to that in the non-transgenic littermates. A relative portion of $CD8^{+}$ single positive thymocytes was about 33.2% in transgenic peripheral T-cells while 50.6% in wild type. Reduction of $CD4^{+}$ cell numbers in transgenic mice was observed (5.9% in transgenic versus 10.3% in non-transgenic). The data from analysis of these transgenic mice indicate that the proximal lck promoter regulated the expression of DT-A gene at high level in developing thymocytes and the DT-A disrupted developing thymocytes in transgenic mice.

• Journal of Preventive Veterinary Medicine
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• v.43 no.4
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• pp.214-220
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• 2019

Although canine brucellosis has been known to be an important re-emerging zoonosis, the pathophysiological mechanisms of Brucella canis infection remains clues to be solved. Different culture models, single and co-culture models, were constructed with canine epithelial cells, D17 and macrophage, DH82 to investigate the induction of immune responses in in vivo B. canis infection. Expression of genes related with induction of immune responses, Th1, Th2 and Th17, was compared in the two different models after the bacterial infection. In this study, expression of cytokine genes, IL-1β, IL-5, IL-6, IL-10, IL-23, and TNF-α was quantified in the DH82 at different time points using RT-qPCR in the two different culture systems after the infection. Cytokine genes related with Th1, IL-1β and TNF-α and Th17, IL-6 and IL-23 were expressed with time-dependent manners in the both systems (p<0.05). However, increase of Th2-related cytokine genes expression was not detectable in the both systems by comparison with control. The expression of Th1 and Th17 related cytokine genes was earlier in single cell culture than those in co-culture model (p<0.05). In general, amounts of the expressed genes were shown higher in single cell model than those in co-culture models. This study indicate that Th1 and Th17-associated immune responses are central to B. canis infection in dogs. In addition, it suggests a specific role of epithelial cells in the B. canis infection in vivo, which should resolved in the further study.

• Korean Journal of Microbiology
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• v.51 no.2
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• pp.115-125
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• 2015

A monoclonal antibody AP64 IgM binds to human acute nonlymphocytic leukemia (ANLL) cell line HL60 and also cross-reacts with the homologous antigen in a rat ANLL cell. This antibody mediated by complement, has leukemia a suppression effect. In this study, we generated a recombinant single-chain variable domain fragment (ScFv) which were derived from $V_H$ and $V_L$ cDNA of AP64 IgM-secreting hybridoma by RT-PCR. The two variable regions were joined with a single 15 amino acid linker $(G_4S)_3$. This recombinant ScFv was expressed as a single polypeptide chain from Escherichia coli BMH 71-18. The recombinant ScFv was purified by applying the periplasmic extract to $Ni^+$-NTA-agarose affinity column and detected with westernblot. The purified recombinant ScFv recognized a surface antigen (about 30 kDa) of HL60 cell line which is the same antigen detected by parental AP64 IgM. But the affinity of ScFv for a surface antigen of HL60 was lower than that of the parental AP64 IgM, which needs to be further improved. Overall, the recombinant ScFv specific to HL60 might be a useful bioreagent for either diagnostic or therapeutic purposes.

• Imaging Science in Dentistry
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• v.37 no.1
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• pp.35-43
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• 2007

Purpose : To observe direct effect of irradiation on cariogenic Streptooccus mutans. Materials and Methods : S. mutans GS5 was exposed to irradiation with a single absorbed dose of 10, 20, 30, and 40Gy. Viability and changes in antibiotic sensitivity, morphology, transcription of virulence factors, and protein profile of bacterium after irradiation were examined by pour plate, disc diffusion method, transmission electron microscopy, RT-PCR, and SDS-PAGE, respectively. Results : After irradiation with 10 and 20Gy, viability of S. mutans was reduced. Further increase in irradiation dose, however, did not affect the viability of the remaining cells of S. mutans. Irradiated 5. mutans was found to have become sensitive to antibiotics. In particular, the bacterium irradiated with 40Gy increased its susceptibility to cefotaxime, penicillin, and tetracycline. Under the transmission electron microscope, number of morphologically abnormal cells was increased as the irradiation dose was increased. S. mutans irradiated with 10 Gy revealed a change in the cell wall and cell membrane. As irradiation dose was increased, a higher number of cells showed thickened cell wall and cell membrane and Iysis, and appearance of ghost cells was noticeable. In RT-PCR, no difference was detected in expression of gtfB and spap between cells with and without irradiation of 40Gy. In SDS-PAGE, proteins with higher molecular masses were gradually diminished as irradiation dose was increased. Conclusion : These results suggest that irradiation affects the cell Integrity of S. mutans, as observed by SDS-PAGE, and as manifested by the change in cell morphology, antibiotic sensitivity, and eventually viability of the bacterium.

• Korean Journal of Microbiology
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• v.42 no.4
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• pp.277-285
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• 2006

The most biofilm forming bacteria in catheter, Esctherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus were isolated and identified from a patient's catheter occuring catheter-associated urinary tract infection (CA-UTI). We examined mRNA expression and its quantification of AIs synthetic genes encoding signal substance of quorum sensing from each bacterial species in order to elucidated quorum sensing mechanism. Both pure cultures for each bacterial strains and a mixed cultures with three were grown for 24 hr and 30 days. Initial densities to be able to detect mRNA expression oil single strains culture were shown at $2.4{\times}10^5$ CFU/ml, $5.4{\times}10^6$ CFU/ml of E. coli for ygaG and S. aureus for luxS, and at $6.9{\times}10^4$ CFU/ml of P. aeruginosa for rhlI and lasI. Also, in mixed culture of three, initial cell densities of mRNA expression were appear to at $7.3{\times}10^5$ CFU/ml, $1.6{\times}10^7$ CFU/ml of E. coli for ygaG and S. aureus for luxS, and at $2.1{\times}10^5$ CFU/ml of P. aeruginosa for rhlI and lasI. Each AIs synthetic gene was expressed in initial cell density and the mRNA expression of the genes were detected continously during 30 days. And then, the quantification of mRNA expression level of ygaG, rhlI, last, and luxS which were related AIs synthesis was done each time point by real-time RT-PCR. Interestingly, the mRNA levels of ygaG, rhlI, lasI, and luxS from the mixed culture was higher than those from each single strain culture. In the case of E. coli ygaG, the amount of transcript from the mixed culture was at least 30 times for that from single culture. In the case of P. aeruginosa rhlI and lasI, the amount of transcript from the mixed culture was at least 40 times and 250 times for that from single strain culture. In the case of S. aureus luxS, the amount of transcript from the mixed culture was at least 5 times for that from single strain culture. And specially, the mRNA expression of rhlI and lasI of P. aeruginosa showed the highest efficency among four AIs synthetic genes.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.6
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• pp.3871-3875
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• 2013

Purpose: MicroRNAs (miRNAs) are small endogenous, non-coding, single-stranded RNAs (approximately 22 nt). Accumulating evidence has shown that aberrant miRNA expression is pronounced and correlated with gastric cancer genesis and progression. Materials and Methods: Expression levels of miR-181a-5p in GC tissues and cell lines were assessed by qRT-PCR and tested for correlation with clinical features. In addition, effects of miR-181a-5p on GC cell growth were investigated. Results: Our findings indicate that miR-181a-5p is upregulated in GC, in correlation with lymph node invasion, nerve invasion and vascular invasion (P<0.05). Enforced expression of miR-181a -5p promoted cell proliferation ability. Conclusions: This study suggested that increased miR-181a-5p is related to GC progression. MiR-181a-5p may represent a potential therapeutic target for GC.

• Biomedical Science Letters
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• v.9 no.3
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• pp.111-121
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• 2003

Recombinant single chain Fv (scFv) antibodies offer many advantages over mouse monoclonal antibodies such as faster clearance from blood, improved tumor localization, reduced human anti-mouse antibody (HAMA) response, and the availability to manipulate the scFv through genetic approaches. The recombinant phage display was constructed using lym-l hybridoma cells as a source of genetic starting material. mRNA was isolated from the corresponding antibodies hybridoma cells. VH and VL cDNA were amplified with RT-PCR and linked with ScFv by linker DNA to form ScFv DNA, which then were inserted into phagemid pCANTAB5E. The phage of positive clones selected with tube containing raji lymphoma cell and infected by competent E. coli HB2151 to express soluble scFv. The scFv lym-l was secreted into the cytosol and culture supernatant and shown to be of expected size (approximately 32 kDa) by western blot. An active scFv lym-l could be produced in E. coli with soluble form and high yield from hybridoma cell line, using phage display system. Immunoreactivity indicated that scFv lym1 showed a potential biding affinity against the raji lymphoma cell as its parental antibody (intact lym-l Ab).