• Nutrition Research and Practice
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• 제11권2호
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• pp.83-89
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• 2017

BACKGROUND/OBJECTIVES: Epithelial-mesenchymal transition (EMT) is involved in not only cancer development and metastasis but also non-cancerous conditions. Hypoxia is one of the proposed critical factors contributing to formation of chronic rhinosinusitis or nasal polyposis. Wheatgrass (Triticum aestivum) has antioxidant, anti-aging, and anti-inflammatory effects. In this study, we analyzed whether wheatgrass has an inhibitory effect on the EMT process in airway epithelial cells. MATERIALS/METHODS: A549 human lung adenocarcinoma cells were incubated in hypoxic conditions ($CO_2$ 5%/$O_2$ 1%) for 24 h in the presence of different concentrations of wheatgrass extract (50, 75, 100, and $150{\mu}g/mL$) and changes in expression of epithelial or mesenchymal markers were evaluated by immunoblotting and immunofluorescence. Accordingly, associated EMT-related transcriptional factors, Snail and Smad, were also evaluated. RESULTS: Hypoxia increased expression of N-cadherin and reduced expression of E-cadherin. Mechanistically, E-cadherin levels were recovered during hypoxia by silencing hypoxia inducible factor (HIF)-$1{\alpha}$ or administering wheatgrass extract. Wheatgrass inhibited the hypoxia-mediated EMT by reducing the expression of phosphorylated Smad3 (pSmad3) and Snail. It suppressed the hypoxia-mediated EMT processes of airway epithelial cells via HIF-$1{\alpha}$ and the pSmad3 signaling pathway. CONCLUSION: These results suggest that wheatgrass has potential as a therapeutic or supplementary agent for HIF-1-related diseases.

• Molecules and Cells
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• 제43권10호
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• pp.889-897
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• 2020

K-RAS is frequently mutated in human lung adenocarcinomas (ADCs), and the p53 pathway plays a central role in cellular defense against oncogenic K-RAS mutation. However, in mouse lung cancer models, oncogenic K-Ras mutation alone can induce ADCs without p53 mutation, and loss of p53 does not have a significant impact on early K-Ras-induced lung tumorigenesis. These results raise the question of how K-Ras-activated cells evade oncogene surveillance mechanisms and develop into lung ADCs. RUNX3 plays a key role at the restriction (R)-point, which governs multiple tumor suppressor pathways including the p14^ARF-p53 pathway. In this study, we found that K-Ras activation in a very limited number of cells, alone or in combination with p53 inactivation, failed to induce any pathologic lesions for up to 1 year. By contrast, when Runx3 was inactivated and K-Ras was activated by the same targeting method, lung ADCs and other tumors were rapidly induced. In a urethane-induced mouse lung tumor model that recapitulates the features of K-RAS-driven human lung tumors, Runx3 was inactivated in both adenomas (ADs) and ADCs, whereas K-Ras was activated only in ADCs. Together, these results demonstrate that the R-point-associated oncogene surveillance mechanism is abrogated by Runx3 inactivation in AD cells and these cells cannot defend against K-Ras activation, resulting in the transition from AD to ADC. Therefore, K-Ras-activated lung epithelial cells do not evade oncogene surveillance mechanisms; instead, they are selected if they occur in AD cells in which Runx3 has been inactivated.

• 대한의생명과학회지
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• 제29권4호
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• pp.280-286
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• 2023

In humic substances, fulvic acid (FA) is a subclass of diverse compounds known as humic substances, which are by-products of organic degradation from microorganisms. FA can suppress the proliferation of tumor cells. Despite numerous studies, the exact mechanism for the various effects of FA is not clearly understood. Based on results demonstrating anti-proliferation effects on human cancer, we investigated whether FA has similar effects on lung cancer in this study. Firstly, the anti-cancer effect of FA in pulmonary epithelial tumor cell lines (TC-1 cells) was examined by confirming its inhibitory effect on the cell proliferation of TC-1 cells. TC-1 cell proliferation was reduced by FA on a dose-dependent and time-dependent manner. After 24 hours of FA treatment, cell morphological changes such as cell volume decrease, non-adherence and increased number of apoptotic cells were clearly observed. In addition, FA induced a DNA ladder pattern by increased of DNA fragments in TC-1 cells. In the intracellular regulatory pathway by FA, we confirmed that FA induced the reduction of the anti-apoptotic protein, Bcl-2 protein levels. These results indicate that FA has anticancer effect by inducing intracellular apoptotic pathway. Further research on the mechanism of anticancer effects will be basic data for the development of potential anticancer drugs.

• Journal of Chest Surgery
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• 제54권6호
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• pp.460-465
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• 2021

Background: Metastasis and recurrence of primary cancer are the main causes of cancer mortality. Disseminated tumor cells refer to cancer cells that cause metastasis from primary cancer to other organs. Several recent studies have suggested that circulating tumor cells (CTCs) are associated with the clinical stage, cancer recurrence, cancer metastasis, and prognosis. There are several methods of isolating CTCs from whole blood; in particular, using a membrane filtration system is advantageous due to its cost-effectiveness and availability in clinical settings. In this study, an animal model of lung cancer was established in nude mice using the human large cell lung cancer cell line H460. Methods: Six-week-old nude mice were used. The H460 lung cancer cell line was injected subcutaneously into the nude mice. Blood samples were obtained from the orbital area before cell line injection, 2 weeks after injection, and 2 weeks after tumor excision. Blood samples were filtered using a polycarbonate 12-well Transwell membrane (Corning Inc., Corning, NY, USA). An indirect immunofluorescence assay was performed with the epithelial cell adhesion molecule antibody. The number of stained cells was counted using fluorescence microscopy. Results: The average size of the tumor masses was 35.83 mm. The stained cells were counted before inoculation, 2 weeks after inoculation, and 2 weeks after tumor excision. Cancer cells generally increased after inoculation and decreased after tumor resection. Conclusion: The CTC detection method using the commercial polycarbonate 12-well Transwell (Corning Inc.) membrane is advantageous in terms of cost-effectiveness and convenience.

• 생명과학회지
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• 제21권2호
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• pp.286-291
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• 2011

본 연구는 인간 폐암세포의 저산소 상태를 재현하기 위한 $CoCl_2$의 처리 조건을 최적화 하였고, 최적화 된 저산소 상태에서 인간 폐암세포의 암화 과정 및 기전을 규명하였다. 인간 폐암세포, A549와 H460에 500 ${\mu}M$ $CoCl_2$를 24시간 처리하였을 때 저산소 상태의 대표적인 전사인자, HIF-$1{\alpha}$의 발현이 증가함을 확인하였고 인간 폐암세포들의 성장에는 전혀 영향을 미치지 않음을 확인하였다. 또한 $CoCl_2$를 처리한 인간 폐암 세포에서 상피-중간엽 이행(epithelial-to-mesenchymal-like transition)의 대표적인 마커인 E-cadherin 발현의 감소와 ${\alpha}$-SMA의 증가를 확인하였고, 세포-세포 간 junction 부위가 깨어짐을 E-cadherin 형광염색 실험을 통하여 확인하였다. 더 나아가 $CoCl_2$를 처리한 인간 폐암 세포에서 상피-중간엽 이행의 분자적 기전을 밝히기 위해 세포벽에 존재하는 인테그린(integrin)의 발현을 웨스턴 블랏팅과 FACS분석을 통하여 알아본 결과, $CoCl_2$를 처리한 인간 폐암세포에서 인테그린 ${\beta}3$발현의 증가를 확인하였다. 뿐만 아니라, $CoCl_2$를 처리한 인간 폐암세포에서 인테그린 ${\beta}3$의 하부 신호전달 물질인 국소부착 카이네이즈(FAK)의 인산화가 증가함을 확인하였다. 상기의 결과로서, 국소부착 카이네이즈의 인산화를 저해함으로써 인간 폐암세포가 악성세포로 전이되는 것을 저해할 수 있을 것으로 기대 되어진다.

• 대한본초학회지
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• 제30권3호
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• pp.1-12
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• 2015

Objectives : In this study, we investigated the effects of Agastachis Herba water (AH-W) extract on compound 48/80-induced mast cell degranulation and histamine release in human mast cells and also anti-asthmatic effect of AH-W extract on ovalbumin (OVA)-induced asthma in mice. Methods : Human mast cells, HMC-1 were treated with AH-W extract in the presence or absence of compound 48/80 (C48/80). Mast cell degranulation was observed by microscope, and the histamine release was measured in culture medium by ELISA. For preparation of asthmatic in vivo model, mice were sensitized (0, 7, and 14 days) with OVA and airway challenged (21, 23, 25, 27, and 29 days). AH-W extract at doses of 100 and 300 mg/kg/body weight was orally administered during OVA challenge once per a day. The levels of immunoglobulin (Ig) E, and Th1/Th2 cytokines, IFN-$\gamma$ and IL-4 were measured in the sera of mice by ELISA. The histopathological change of lung tissues was observed by hematoxylin and eosin (H&E) and Periodic Acid Schiff (PAS) staining. Results : The treatment of AH-W extract significantly decreased the mast cell degranulation and histamine release in C48/80-stimulated HMC-1 cells. In addition, The administration of AH-W extract at does of 100 and 300 mg/kg significantly decreased the serum levels of OVA-specific IgE compared with those of OVA control group. In H&E and PAS staining, AH-W extract inhibited OVA-induced airway inflammation, and inflammatory cells infiltration, and also histopathological damages on lung tissues such as bronchiole epithelial desquamation, goblet cells hyperplasia, and mucin releasing. Conclusions : These results indicate that AH-W extract may improve asthmatic symptoms through mast cell stabilization and inhibiting the lung inflammation in bronchial asthma.

• Journal of Chest Surgery
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• 제36권9호
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• pp.666-673
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• 2003

폐암의 주된 원인으로 알려진 흡연은 그 악성세포 발현기전이 아직 정확히 규명된 바 없다. 이에 저자들은 흡연에 의한 발암성의 지표로 흡연 중에 특이적으로 존재하는 강력한 발암물질인 NNK(4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone)를 이용하여 흡연에 따른 폐암의 발생과 그 Protein kinase C (PKC) isoform과 관련된 기전에 관한 연구를 시도하였다. 대상 및 방법: 인체 상피세포를 NNK에 노출시킨 후 saturation density, soft agar colony formation, cell aggregation 및 foci의 출현 등의 양상을 파악하여 세포 발암성 여부를 관찰하였으며 NNK를 15분간 노출시킨 후 PKC의 변화는 세포 내 PKC isoform의 양을 cytosolic fraction과 membrane fraction으로 분리하여 측정하여 분석하였다. 결과: NNK 투여군에서 saturation density, soft agar colony formation, cell aggregation 및 foci의 출현 시기 등의 세포 발암성을 뚜렷이 나타내었으며 PKC isoform분석의 경우 PKC-$\alpha$의 membrane fraction의 뚜렷한 증가를 보였으며 이러한 활성은 용량-의존적인 형태를 유지하였다. PKC-$\varepsilon$은 NNK 처리 시 용량-의존적으로 cytosol fraction의 감소 및 membrane fraction의 증가를 뚜렷하게 보였고 NNK에 의한 PKC-λ의 변화는 감지되지 않았다. 결론: 본 연구는 화학적 발암물질인 NNK가 인체발암화에 관여함을 재차 확인하면서 초기 과정에 관여하는 PKC isoform의 변화를 분석함으로써 total PKC활성이 아닌 isoform 각각에 대한 변화를 확인하였다는 점에서 앞으로 인체상피세포 기원의 폐암 생성 기전 연구에 기여할 것으로 생각한다.

• 생명과학회지
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• 제23권8호
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• pp.1050-1056
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• 2013

Streptococcus pneumoniae는 전 세계적으로 급성 호흡기 질환 높은 사망률 나타내며, 정상인의 비인후부에 존재하여 호흡기 감염을 통해 폐렴, 수막염, 중이염, 패혈증, 복막염, 골수염 등을 일으킨다. 그러나 S. pneumoniae가 폐 조직에 침입하는 분자적 메커니즘과 혈류를 통한 침입은 많은 연구에도 불구하고 아직 명확하게 알려지지 않았다. 그러므로 본 실험에서는 S. pneumoniae D39의 감염 및 침입에 대한 분자 메카니즘을 알고자 사람의 폐암상피 세포 유래 A549 세포를 이용하여 감염 후 시간의 경과에 따라 변화되는 A549 세포의 모양을 관찰하였으며, 또한 숙주세포의 단백질 패턴 변화를 조사하였다. 일부 A549 세포는 감염 후 2 시간부터 세포의 모양이 둥근형태로 변화된 것으로 관찰되었으며, 감염 3 시간째에는 세포의 모양이 둥글며 filopodia가 아주 잘 발달하였다. 감염 4 시간에 도달하게 되면 거의 모든 A549 세포가 둥글며 잘 발달된 filopodia를 형성하였다. 감염 후 각 시간 별 A549 세포의 총 단백질들을 추출하여 시간의 경과에 따라 특이적으로 양 적인 변화를 나타내는 단백질을 MALDI-TOF 분석법을 사용하여 동정하였다. Streptococcus pneumoniae D39 감염 후 시간에 따라 변화하는 단백질 중 대다수가 특이하게도 molecular chaperone에 속하는 단백질들이었다. 대표적인 cytosol chaperone인 Hsp90과 Hsp70의 경우 감소하는 패턴을 나타낸 반면에 endoplasmic reticulum (ER)에 존재하는 chaperone인 Grp94와 Grp78 (BiP)은 감염 후 점차 증가하는 패턴을 나타내었다. ER chaperone인 Grp94와 Grp78의 증가는 ER stress signaling pathway와 관련 있는 것으로 알려져 있어, S. pneumoniae D39의 감염에 의한 이들 단백질의 변화 패턴을 ER stress를 유발 시켰을 때와 비교하였다. Tunicamycin 또는 thapsigargin으로 처리하여 ER stress를 유발시킨 A549 세포의 형태는 변화하지 않았으며 흡착세포의 형태를 유지하였다. 그러나 Western blot을 통한 molecular chaperone의 분석 결과는 S. pneumoniae D39 감염의 경우와 일치하였다. 본 연구에서 얻은 결과는 S. pneumoniae D39의 감염은 A549 세포의 형태적 변화를 유발하며 또한 molecular chaperone 증가와 감소를 유발한다는 것을 보여주며, 특이적으로 Grp94와 Grp78이 증가되는 것으로 보아 S. pneumoniae D39 감염은 A549 세포 내 ER stress를 유발한다고 생각된다.

• The Journal of Advanced Prosthodontics
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• 제7권2호
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• pp.138-145
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• 2015

PURPOSE. The objective of this study was to conduct an in vitro comparative evaluation of polished and laser-dimpled titanium (Ti) surfaces to determine whether either surface has an advantage in promoting the attachment of epithelial-like cells and fibroblast to Ti. MATERIALS AND METHODS. Forty-eight coin-shaped samples of commercially pure, grade 4 Ti plates were used in this study. These discs were cleaned to a surface roughness (Ra: roughness centerline average) of 180 nm by polishing and were divided into three groups: SM (n=16) had no dimples and served as the control, SM15 (n=16) had $5-{\mu}m$ dimples at $10-{\mu}m$ intervals, and SM30 (n=16) had $5-{\mu}m$ dimples at $25-{\mu}m$ intervals in a $2{\times}4mm^2$ area at the center of the disc. Human gingival squamous cell carcinoma cells (YD-38) and human lung fibroblasts (MRC-5) were cultured and used in cell proliferation assays, adhesion assays, immunofluorescent staining of adhesion proteins, and morphological analysis by SEM. The data were analyzed statistically to determine the significance of differences. RESULTS. The adhesion strength of epithelial cells was higher on Ti surfaces with $5-{\mu}m$ laser dimples than on polished Ti surfaces, while the adhesion of fibroblasts was not significantly changed by laser treatment of implant surfaces. However, epithelial cells and fibroblasts around the laser dimples appeared larger and showed increased expression of adhesion proteins. CONCLUSION. These findings demonstrate that laser dimpling may contribute to improving the peri-implant soft tissue barrier. This study provided helpful information for developing the transmucosal surface of the abutment.

• Tuberculosis and Respiratory Diseases
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• 제45권4호
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• pp.760-765
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• 1998

연구배경: 암세포에서 포도당의 유입이 증가되어 있다는 사실이 오래 전부터 알려져 왔고 이런 현상을 이용하여 FDG-PET 영상이 암의 진단에 이용되고 있다. 그러나, 암세포에서 포도당 유입이 증가하는 기전에 대해서는 모르고 있다. 최근, 여러 연구에서 소화기계의 악성종양과 두경부종양에서 포도당 운반체의 mRNA 의 존재가 증명되었고, 포도당 운반체가 암세포에서의 포도당 유입 증가와 관련이 있을 가능성을 시사하였다. 폐암에서도 포도당대사가 항진되어 있다. 저자등은 폐암에서의 포도당 유입이 증가하는 기전에 대해 알아 보기 위하여 사람 폐암세포주에서 포도당 mRNA의 발현여부를 확인하였다. 방 법: 15종의 사람 폐암 세포주와 불멸화시킨 기관지 상피세포주에서 total RNA를 추출하였다. $20{\mu}g$의 total RNA를 전기영동시킨후, 포도당 운반체 1형과 3 형에 대한 cDNA를 probe로 Northern blot analysis를 시행하였다. 결 과: 14종의 사람 폐암 세포주중에서 13종에서 포도당 운반체 1형의 mRNA 발현을 확인하였고, 14종의 사람 폐암 세포주중에서 10종에서 포도당 운반체 3형의 mRNA 발현을 확인하였다. 불멸화시킨 기관지 상피세포주의 포도당 운반체 1형의 mRNA 발현을 확인할 수 있었고 3형의 mRNA 발현은 확인할 수 없었다. 결 론: 폐암에서 포도당 대사의 증가는 포도당 운반체 1형과 3형의 발현과 관련이 있을 것으로 사료된다.