• Molecules and Cells
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• 제26권1호
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• pp.5-11
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• 2008

Stalled DNA replication forks activate specific DNA repair mechanism called post-replication repair (PRR) pathways that simply bypass DNA damage. The bypassing of DNA damage by PRR prevents prolonged stalling of DNA replication that could result in double strand breaks (DSBs). Proliferating cell nuclear antigen (PCNA) functions to initiate and choose different bypassing pathways of PRR. In yeast, DNA replication forks stalled by DNA damage induces monoubiquitination of PCNA at K164, which is catalyzed by Rad6/Rad18 complex. PCNA monoubiquitination triggers the replacement of replicative polymerase with special translesion synthesis (TLS) polymerases that are able to replicate past DNA lesions. The PCNA interaction motif and/or the ubiquitin binding motif in most TLS polymerases seem to be important for the regulation of TLS. The TLS pathway is usually error-prone because TLS polymerases have low fidelity and no proofreading activity. PCNA can also be further polyubiquitinated by Ubc13/ Mms2/Rad5 complex, which adds an ubiquitin chain onto monoubiquitinated K164 of PCNA. PCNA polyubiquitination directs a different PRR pathway known as error-free damage avoidance, which uses the newly synthesized sister chromatid as a template to bypass DNA damage presumably through template switching mechanism. Mammalian homologues of all of the yeast PRR proteins have been identified, thus PRR is well conserved throughout evolution. Mutations of some PRR genes are associated with a higher risk for cancers in mice and human patients, strongly supporting the importance of PRR as a tumor suppressor pathway.

• Biomolecules & Therapeutics
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• 제28권5호
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• pp.405-413
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• 2020

Fibroblast-like synoviocytes (FLS) play a crucial role in initiating rheumatoid arthritis. B-cell activating factor (BAFF) plays a role in FLS survival as well as in B cell maturation and maintenance. Here, we investigated whether tumor necrosis factor (TNF)-α-induced BAFF expression controls FLS migration and whether BAFF expression in FLS could be regulated by KR33426 which is the inhibitor of BAFF binding to BAFF receptors (BAFF-R) by using MH7A synovial cells transfected with the SV40 T antigen. More TNF-α-treated cells migrated compared to the control. TNF-α increased BAFF expression in FLS, significantly. FLS migration was inhibited by the transfection with BAFF-siRNA. KR33426 also inhibited BAFF expression increased by TNF-α treatment in FLS as judged by western blotting, PCR, and transcriptional activity assay. Kinases including JNK, p38 and Erk were activated by TNF-α treatment. While JNK and p38 were inhibited by KR33426 treatment, no changes in Erk were observed. Transcription factors including p65, c-Fos, CREB and SP1 were enhanced by TNF-α treatment. Among them, c-Fos was inhibited by KR33426 treatment. Small interference(si)-RNA of c-fos decreased BAFF transcriptional activity. FLS migration induced by TNF-α was inhibited by the transfection with BAFF-siRNA. KR33426 increased Twist, Snail, Cadherin-11 and N-Cadherin. In contrast, KR33426 decreased E-cadherin and TNF-α-enhanced CCL2. Taken together, our results demonstrate that synovial cell migration via CCL2 expression could be regulated by BAFF expression which is decreased by KR33426 and c-Fos-siRNA. It suggests for the first time that the role of BAFF-siRNA on FLS migration might be matched in the effect of KR33426 on BAFF expression.

• Biomolecules & Therapeutics
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• 제30권6호
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• pp.546-552
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• 2022

Epidermal cell adhesion molecule (EpCAM) is a tumor-associated antigen (TAA), which has been considered as a cancer vaccine candidate. The EpCAM protein fused to the fragment crystallizable region of immunoglobulin G (IgG) tagged with KDEL endoplasmic reticulum (ER) retention signal (EpCAM-FcK) has been successfully expressed in transgenic tobacco (Nicotiana tabacum cv. Xanthi) and purified from the plant leaf. In this study, we investigated the ability of the plant-derived EpCAM-FcK (EpCAM-FcK^P) to elicit an immune response in vivo. The animal group injected with the EpCAM-FcK^P showed a higher differentiated germinal center (GC) B cell population (~9%) compared with the animal group injected with the recombinant rhEpCAM-Fc chimera (EpCAM-Fc^M). The animal group injected with EpCAM-FcK^P (~42%) had more differentiated T follicular helper cells (Tfh) than the animal group injected with EpCAM-Fc^M (~7%). This study demonstrated that the plant-derived EpCAM-FcK fusion antigenic protein induced a humoral immune response in mice.

• Tuberculosis and Respiratory Diseases
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• 제53권3호
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• pp.265-274
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• 2002

배 경 :종양 특이 항원인 MAGE 유전자는 여러 종류의 암조직에서 발현되지만 정상조직에서는 고환의 생식 세포를 제외하고는 발현이 없다. 본 연구에서는 MAGE 유전자의 암 특이적 발현을 폐암의 진단에 활용할 수 있는지를 유도객담을 이용하여 알아보고자 하였다. 방 법 :조직학적으로 폐암으로 진단된 환자 30명, 대조군으로 기타 폐질환 환자 14명에서 얻은 유도객담을 3cc의 보존제(guanidinium isothiocyanate, Triton X-100)와 잘 섞어 냉장보관 후 당일 MAGE A 1-6를 동시에 발견할 수 있도록 고안된 2종류의 primer(MAGE common primer C1/C2, C3/C4)를 이용하여 nested PT PCR를 실시하여 MAGE 유전자의 발현 유무를 조사하였다. 결 과 : MAGE common primer를 이용한 nested RT-PCR에서 폐암환자 30 명 중 24명 (80%)에서 MAGE가 양성으로 발현되었고 대조군에서는 전례에서 발견되지 않았다(p=0.001). 편평세포암 17례 중 13례(76.5%), 선암 9례 중 7례 (77.8%)에서 소세포암은 4례에서 모두 MAGE 양성이었으며 각 군간에 발현율의 차이는 없었다(p=0.56). MAGE양성인 환자 24명 중 약 반수인 11 명에서는 기관지 내시경검사에서 육안적으로 종양 병변이 발견되지 않는 경우였다. 결 론 : 유도객담에서 MAGE 유전자는 암 환자에서 선택적으로 높은 빈도의 발현을 보이는 것을 확인하였다. 이러한 결과로 객담을 이용한 MAGE 검사법이 폐암의 검색, 조기진단 그리고 치료 후 경과 관찰에 유용하게 사용될 수 있을 것으로 생각된다.

• 한국식품영양과학회지
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• 제40권12호
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• pp.1662-1667
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• 2011

안토시아닌(anthocyanins)은 플라보노이드에 속하고 항산화 활성들을 포함한 그들의 다양한 건강 유익성에 대해 알려져 있다. 그들 중 검정콩 껍질에서 분리한 주요 안토시아닌은 glycopyranose를 함유하고 있는 배당체이다. 천식은 호염기성 세포(basophils)와 비만세포(mast cells)를 포함한 다양한 면역세포와 관련된 알레르기 관련 질병이다. 호산구(eosinophils), 호염기성 세포, 비만세포는 탈과립화에 의한 천식-특이적 보조 2(T-helper 2) 사이토카인 분비 그리고 계속해서 일어나는 증폭과 같은 염증을 일으키는 매개체의 증가를 통해 알레르기 천식(allergic asthma)에서 중요한 역할을 한다. 흰쥐 호염기성 백혈병(rat basophilic leukemia) RBL-2H3 세포는 알레르기 반응을 측정하기 위해 가장 일반적으로 사용되는 in vitro 모델이다. 본 연구에서는 검정콩 껍질 안토시아닌이 항원으로 자극한 RBL-2H3 세포에서 탈 과립 그리고 Th2 사이토카인 생산에 미치는 효과를 조사하였다. 세포 탈과립은 ${\beta}$-hexosaminidase의 방출을 검출함으로써 평가하였다. IgE-항원 복합체로 자극한 RBL-2H3 세포내 ${\beta}$-hexosaminidase 방출과 Th2 사이토카인 생산이 무처리군의 그것과 비교하여 더 높았다. 안토시아닌은 RBL-2H3 세포의 IgE-항원 복합체 유도 탈과립을 현저하게 억제시켰고 RBL-2H3 세포내 IgE-항원 복합체-매개체 interleukin(IL)-4, IL-13 그리고 TNF-${\alpha}$ 생산을 저해하였다. 이러한 결과는 검정콩 껍질 유래 안토시아닌이 알레르기 반응(allergic reaction)을 현저히 저해하는 효과가 있음을 보였고, 이들 안토시아닌이 향후 알레르기 천식을 억제하거나 개선하는데 유용한 물질로 사용될 가능성이 있을 것으로 판단되었다.

• Asian Pacific Journal of Cancer Prevention
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• 제15권22호
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• pp.9635-9641
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• 2014

Background: This retrospective study was aimed to investigate the efficacy of prophylactic agents in hepatocellular carcinoma (HCC) patients receiving TACE and compare the difference between lamivudine and entecavir. Materials and Methods: A consecutive series of 203 HBV-related HCC patients receiving TACE were analyzed including 91 patients given prophylactic agents. Virologic events, defined as an increase in serum HBV DNA level to more than 1 log10 IU/ml higher than the nadir level, hepatitis flares due to HBV reactivation and progression free survival (PFS) were the main endpoints. Results: Some 48 (69.6%) reached virologic response. Prophylaxis significantly reduced virologic events (8.8% vs 58.0%, p=0.000) and hepatitis flares (1.1% vs 13.4%, p=0.001). Patients presenting undetectable HBV DNA levels displayed a significantly improved PFS as compared to those who never achieved undetectable HBV DNA. Prophylaxis and e-antigen positivity were the only significant variables associated with virologic events. In addition, prophylaxis was the only independent protective factor for hepatitis flares. Liver cirrhosis, more cycles of TACE, HBV DNA negativity, a lower Cancer of the Liver Italian Program score, non-metastasis and no hepatitis flares were protective factors for PFS. Prophylactic lamivudine demonstrated similar efficacy as entecavir. Conclusions: Prophylactic agents are efficacious for prevention of HBV reactivation in HCC patients receiving TACE. Achievement of undetectable HBV DNA levels displayed a significant capability in improving PFS. Moreover, persistent tumor residual lesions, positive HBV DNA and hepatitis B flares might be causes of tumor progression in these patients.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제32권2호
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• pp.101-106
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• 2006

Purpose: The purpose of this study is to evaluate the value of proliferation factors, Ki67 and PCNA, as prognostic markers predicting the survival and neck metastasis in patients with oral cancer. Methods: 101 patients with HNSCCs, were followed retrospectively for a median period of 60 months(from 16 to 82 months). All tumors were resected surgically and examined by conventional light microscopy, immunohistochemistry. The age, sex, tumor location, clinical stage(size), metastasis, proliferative activity index(assessed by proliferating cell nuclear antigen(PCNA) and Ki67 immunoreactivity) were considered as potential prognostic factors and were correlated with patient survival. Results: Ki67 staining results ranged from 5% to 80% of tumor cell nuclei, with a median of 25%. PCNA staining results ranged from 1% to 90% with a median of 50%. With a cut-off point of 25%, patients with lower Ki67 scores showed survival advantages over those with higher Ki67 scores (p=0.0089). With cut-off point of 50%, patients with lower PCNA scores showed survival advantages over those with higher PCNA scores (p=0.0104). Pathologically neck node positive patients(n=27) showed higher PCNA expression(p=0.02) than pathologically negative neck node patients(n=39). Conclusions: The lower expressions of Ki67 and PCNA were associated with favorable prognosis such as higher survival rate and lower neck node metastasis.

• Tuberculosis and Respiratory Diseases
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• 제51권2호
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• pp.135-146
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• 2001

배 경 : 암세포는 정상 세포와 다르므로 면역 기전에 의해 제거되어야 함에도 불구하고 암이 발생하는 것은 암세포가 면역 감시 체계를 회피하기 때문이다. 약제감수성 증강 유전자인 herpes simplex thymidine kinase(HSTK) 유전자를 이용하여 암세포를 파괴하여 종양 특이항원이 더 잘 유리되도록 하고 사이토카인 유전자를 이용하여 면역세포를 유도하여 이 장애를 극복할 수 있는지 보고자 이 실험을 하였다. 방 법 : Lewis 폐암 세포주(LLC)에 adenovirus를 이용하여 HSTK를 형질도입하고 이에 의해 ganciclovir에 대한 LLC의 감수성을 증강시키는지를 관찰하고 mixed population assay를 이용하여 bystander 효과를 관찰하였다. Ad-HSTK, Ad-IL-2, Ad-GMCSF의 형질도입이 LLC의 종양 형성 능력에 영향을 미치는지 관찰하였다. 또한 그러한 형질 도입이 기존의 종양에 대한 항암 효과를 가져오는지 관찰하였다. 항암 효과의 기전을 확인하기 위해 쥐의 비장을 관찰하였다. 결 과 : Ad-HSTK의 형질도입은 ganciclovir에 대한 LLC의 감수성을 현저하게 증강시켰다. Ad-HSTK, Ad-IL-2, Ad-GM-CSF를 형질도입한 LLC를 쥐에 주사하고 ganciclovir로 처리하였을 때 종양 형성 능력이 감소하였다. Ad-HSTK, Ad-IL-2, Ad-GM-CSF를 형질도입한 LLC를 종양백신으로 사용하였을때 종양 성장이 어느 정도 저해되는 것을 관찰하였다. 특히 HSTK와 GM-CSF를 복합 형질도입했을 때 더 강력한 항암효과가 일어나는 것을 관찰하였다. 그러나 HSTK와 IL-2을 복합 형질도입했을 때는 각각을 단독으로 형질도입했을 때보다 항암효과가 상승되지 않았다. HSTK와 GM-CSF의 복합 형질도입한 LLC를 종양백신으로 사용하였을 때 비장의 수상세포 침윤이 현저히 증가하였다. 결 론 : HSTK와 GM-CSF의 복합 형질도입으로 만든 종양백신은 수상세포를 활성화시키므로써 항암면역기능을 유의하게 증강시킬 수 있었다.

• Asian-Australasian Journal of Animal Sciences
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• 제33권9호
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• pp.1507-1519
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• 2020

Objective: The current research was aimed to profile the transcriptomic picture of the peripheral blood lymphocytes (PBLs) associated with immunity in Chinese Holsteins supplemented orally with coated folic acid during the periparturient period. Methods: The total of 123 perinatal cows were selected for this study and divided into three groups; group A (n = 41, 240 mg/500 kg cow/d), group B (n = 40, 120 mg/500 kg cow/d) and group C (n = 42, 0 mg/cow/d) based on the quantity of folic acid fed. Three samples of PBLs were selected from each folic acid treated group (high, low, and control) and RNA sequencing method was carried out for transcriptomic analysis. Results: The analysis revealed that a higher number of genes and pathways were regulated in response to high and low folic acid supplementation compared to the controls. We reported the novel pathways tumor necrosis factor (TNF) signaling, antigen processing and presentation, Staphylococcus aureus infection and nuclear factor (NF)-kappa B signaling pathways) and the key genes (e.g. C-X-C motif chemokine ligand 10, TNF receptor superfamily member 1A, cluster difference 4, major histocompatibility complex, class II, DQ beta, NF-kappa-B inhibitor alpha, and TNF superfamily 13) having great importance in immunity and anti-inflammation in the periparturient cows in response to coated folic acid treatment. Conclusion: Collectively, our study profiled first-time transcriptomic analysis of bovine lymphocytes and compared the involved cytokines, genes, and pathways between high vs control and low vs control. Our data suggest that the low folic acid supplementation (120 mg/500 kg) could be a good choice to boost appropriate immunity and anti-inflammation as well as might being applied to the health improvement of perinatal dairy cows.

• 한국수의병리학회지
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• 제2권2호
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• pp.95-106
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• 1998

The prevalence of primary liver carcinoma (PLC) is relatively high in Clonorchis sinensis (CS) endemic areas in Korea. PLC is a malignant tumor which can be subclassified into hepatocellular carcinoma and cholangiocarcinoma(CC). CC has been associated with clonorchiasis, but it is unclear whether clonorchiasis is associated with hepatocarcinogenesis. This experiment was designed to investigate relationships between clonorchiasis and early changes of hepatocarcinogenesis. Sixteen Sprague-Dawley rats weighing 150g were divided into two groups of 8 rats in each. All rats were fed choline-devoid(CD) diet for 4 weeks. Group 1 was given 0.015-0.020% diethylnitrosamine(DEN) as drinking water for 1 week. After one week, the rats were treated orally with 1% N-acetylaminofluorene(AAF) (5 times per week for 2 weeks). Group 2 was treated equally to group 1 except for CS infection during AAF treatment. Two rats in each group were sacrificed at 4th, 5th, 6th and 7th week of the experiment. Livers were stained with OV -6, proliferating cell nuclear antigen(PCNA) and GST-p. Results were as follows: Group 2 livers showed more oval cell proliferation in parenchyma and portal areas at the 4th, 5th, 6th and 7th weeks than did livers of group 1 (p＜0.01). PCNA was mostly localized in oval cell populations, rather than hepatocytes and biliary cells. The ratio of oval cells to hepatocytes was much higher in group 2 than in group l(p＜0.01 The ratio of hepatocytes to biliary cells is higher in group 2 than in group 1 (p＜0.05), More group 2 acidophilic foci reacted to GST-p monoclonal antibody than in the noninfected group. It appeared that CS infection promoted potentially precancerous acidophilic foci and oval cell proliferation.