• Molecular & Cellular Toxicology
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• 제2권3호
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• pp.159-165
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• 2006

To determine the anticancer effect of D-amygdalin (D-mandelinitrole-${\beta}$-D-gentiobioside) in human chronic myeloid leukemia cells K562, we profiled the gene expression between amygdalin treatment and control groups. Through 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay, the cytotoxicity of D-amygdalin was $57.79{\pm}1.83%$ at the concentration of 5 mg/mL for 24 h. We performed cDNA microarray analysis and compared the gene expression profiles between D-amygdalin (5 mg/mL, 24 h) treatment and control groups. Among the genes changed by D-amygdalin, we paid attention to cell cycle-related genes, and particularly cell cycle regulator genes; because arrest of cell cycle processing was ideal tactic in remedy for cancer. In our data, expressions of cyclin-dependent kinase inhibitor 1B (p27, Kip1) (CDKN1B), ataxia telangiectasia mutated (includes complementation groups A, C, and D) (ATM), cyclin-dependent kinase inhibitor 1C (p57, Kip2) (CDKN1C), and CHK1 checkpoint homolog (CHEK1, formally known as CHK1) were increased, while expressions of cyclin-dependent kinase 2 (CDK2), cell division cycle 25A (CDC25A), and cyclin E1 (CCNE1) were decreased. The pattern of these gene expressions were confirmed through RT-PCR. Our results showed that D-amygdalin might control cell cycle regulator genes and arrest S phase of cell cycle in K562 cells as the useful anticancer drug.

• Journal of Korean Neurosurgical Society
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• 제66권6호
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• pp.642-651
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• 2023

Objective : Endothelial colony-forming cells (ECFCs) have been reported to play an important role in the pathogenesis of moyamoya disease (MMD). We have previously observed stagnant growth in MMD ECFCs with functional impairment of tubule formation. We aimed to verify the key regulators and related signaling pathways involved in the functional defects of MMD ECFCs. Methods : ECFCs were cultured from peripheral blood mononuclear cells of healthy volunteers (normal) and MMD patients. Low-density lipoproteins uptake, flow cytometry, high content screening, senescence-associated β-galactosidase, immunofluorescence, cell cycle, tubule formation, microarray, real-time quantitative polymerase chain reaction, small interfering RNA transfection, and western blot analyses were performed. Results : The acquisition of cells that can be cultured for a long time with the characteristics of late ECFCs was significantly lower in the MMD patients than the normal. Importantly, the MMD ECFCs showed decreased cellular proliferation with G1 cell cycle arrest and cellular senescence compared to the normal ECFCs. A pathway enrichment analysis demonstrated that the cell cycle pathway was the major enriched pathway, which is consistent with the results of the functional analysis of ECFCs. Among the genes associated with the cell cycle, cyclin-dependent kinase inhibitor 2A (CDKN2A) showed the highest expression in MMD ECFCs. Knockdown of CDKN2A in MMD ECFCs enhanced proliferation by reducing G1 cell cycle arrest and inhibiting senescence through the regulation of CDK4 and phospho retinoblastoma protein. Conclusion : Our study suggests that CDKN2A plays an important role in the growth retardation of MMD ECFCs by inducing cell cycle arrest and senescence.

• Radiation Oncology Journal
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• 제21권4호
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• pp.306-314
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• 2003

목적: K562 세포의 방사선에 의한 세포 사망은 mitotic catastrophe 현상이 위주로 나타나지만 herbimycin A (HMA)에 의하여 apoptosis 반응이 촉진되는 반면 genisteln에 의하여 두 가지 형태의 세포사망이 모두 억제된다. 본 연구에서는 HMA와 genistein에 의한 K562세포의 방사선 유도 세포주기 조절 변화와 세포 사망 양상의 연관성을 조사하였다. 대상 및 방법: 지수증식기의 KS62 세포에 6 MV 선형가속기(Clinac 1,m C, Varian)를 이용하여 200~300 cGy/min의 선량률로 10 Gy를 균일하게 조사하였다. HMA와 genistein은 각각 250 nM와 25$\mu$M농도로 방사선 조사 후 즉시 투여하였다. 실험에서는 세포주기, 오절인자의 발현 및 활성, 노화 및 분화정도 등에 있어서의 시간에 따른 변화를 조사하였다. 결과: 방사선 단독조사에서 KS62세포는 G2기의 정체를 보였으나 정상적인 053을 가지는 세포와는 달리 지속적인 세포주기의 정체를 보이지 않았다. G2정체가 유지되는 동안 cyclin Bl의 점진적인 증가를 관찰할 수 있었으며, 이는 염색체의 복제가 완료되지 않은 상태에서 M기로 진행하여 미성숙한 염색체 응축과 mitotic catastrophe 현상이 나타나는 것과 일치한다. 방사선 조사와 함께 HMA를 투여한 경우에는 G2정체가 빠르게 해소되었으며 동시에 Gl기에서 세포가 정체되는 양상을 보였다. 세포주기 조절인자 cdc2 kinase 활성 증가와 cyclln I와 A 발현 및 CDK2 활성의 감소 등의 현상으로 설명되며, 이는 apoptosis의 증가와 연관성을 갖는다. 반면 genistein의 경우에는 cyclin Bl과 떨cfsc 발현 및 cdc2활성이 모두 감소하는 등 G2정체를 계속 유지하였다. 이와 함께 방사선에 의한 노화와 megakaryocyte로의 분화도 지속되는 것을 관찰할 수 있었다. 결론: HMA와 genistein에 의한 KS62세포의 방사선 유도 세포사망의 변화는 세포주기 조절과 밀접하게 연관되어 있음을 확인하였다. 이는 다양한 방사선 유도 세포사망의 기전을 이해하는 데 독창적인 모델을 제공하며, 방사선을 이용한 암 치료법의 개발에 새로운 표적을 제공할 수 있을 것이다.

• Asian Pacific Journal of Cancer Prevention
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• 제16권3호
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• pp.965-970
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• 2015

Colorectal cancer is one of the most severe subtypes of cancer, and has the highest propensity to manifest as metastatic disease. Because of the lack of knowledge of events that correlate with tumor cell migration and invasion, few therapeutic options are available. The current study aimed to explore the mechanism of colorectal cancer in hope of identifying the ideal target for future treatment. We first discovered the pro-tumor effect of a controversial cell cycle regulator, cylin-dependent kinase inhibitor 3 (CDKN3), which is highly expressed in colorectal cancer, and the possible related signaling pathways, by bioinformatics tools. We found that CDKN3 had remarkable effects in suppressing colorectal cancer cell proliferation and migration, inducing cell cycle arrest and apoptosis in a colorectal cancer cell line, SW480 cells. Our study, for the first time, provided consistent evidence showing overexpression of cell cycle regulator CDKN3, in colorectal cancer. The in vitro studies in SW480 cells revealed a unique role of CDKN3 in regulating cellular behavior of colorectal cancer cells, and implied the possibility of targeting CDKN3 as a novel treatment for colorectal cancer.

• BMB Reports
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• 제49권10호
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• pp.527-528
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• 2016

In embryonic stem cells (ESCs), cell cycle regulation is deeply connected to pluripotency. Especially, core transcription factors (CTFs) which are essential to maintaining the pluripotency transcription programs should be reset during M/G1 transition. However, it remains unknown about how CTFs are governed during cell cycle progression. Here, we describe that the regulation of Oct4 by Aurora kinase b (Aurkb)/protein phosphatase 1 (PP1) axis during the cell cycle is important for resetting Oct4 to pluripotency and cell cycle related target genes in determining the identity of ESCs. Aurkb starts to phosphorylate Oct4(S229) at the onset of G2/M phase, inducing the dissociation of Oct4 from chromatin, whereas PP1 binds Oct4 and dephosphorylates Oct4(S229) during M/G1 transition, which resets Oct4-driven transcription for pluripotency and the cell cycle. Furthermore, Aurkb phosphormimetic and PP1 binding-deficient mutations in Oct4 disrupt the pluripotent cell cycle, lead to the loss of pluripotency in ESCs, and decrease the efficiency of somatic cell reprogramming. Based on our findings, we suggest that the cell cycle is directly linked to pluripotency programs in ESCs.

• Journal of Microbiology and Biotechnology
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• 제13권4호
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• pp.607-612
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• 2003

To elucidate the action mechanism of MCS-C2, a novel analogue of toyocamycin and sangivamycin, its effect on the expression of cell cycle-related proteins in the human myelocytic leukemia cell line HL-60 was examined using Western blotting and a flow cytometric analysis. MCS-C2, a selective inhibitor of cyclin-dependent kinases, was found to inhibit cell growth in a time- and dose-dependent manner, and inhibits cell cycle progression by inducing the arrest at G1 and G2/M phases, in HL-60 cells. The flow cytometric analysis revealed an appreciable arrest of cells in the G2/M phase of the cell cycle after treatment with MCS-C2. The HL-60 cell population increased gradually from 13% at 0 h, to 28% at 12 h in the G2/M phase, after exposure to $2{\;}\mu\textrm{M}$ MCS-C2. Furthermore, Western blot analysis demonstrated that MCS-C2 induced the cell cycle arrest at G1 phase through the inhibition of pRb phosphorylation. Hypophosphorylated pRb accumulated after treatment with $5{\;}\mu\textrm{M}$ MCS-C2 for 12 h, whereas, the level of hyperphosphorylated pRb was reduced. Thus, treatment of the cell with MCS-C2 suppressed the hyperphosphorylated form of pRb with a commensurate increase in the hypophosphorylated form.

• BMB Reports
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• 제43권4호
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• pp.273-278
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• 2010

The cell cycle is regulated by cyclin-dependent kinase (CDK)-cyclin complexes as well as other regulators. We isolated Kip-related protein 4 (KRP4) cDNA that encodes 289 amino acids including six conserved domains. To investigate the expression pattern of KRP4 as well as of other cell cycle-related genes associated with plant hormones, Arabidopsis seedlings were cultured on MS medium containing auxin or cytokinin. All seedlings treated with phytohormones displayed an increased proportion of cells in S phase. A higher proportion of cells in G2 phase was observed in seedlings treated with NAA. RT-PCR confirmed that the expression of KRP4 was decreased after treatment with phytohormones, and that CDKA and D-type cyclin transcription was increased. Additionally, mitotic cyclins were up-regulated by NAA treatment. These results suggest that KRP4 as well as other cell cycle-related genes might contribute to the control of plant growth in response to exogenous hormones.

• Tuberculosis and Respiratory Diseases
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• 제44권4호
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• pp.796-805
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• 1997

연구배경 : 세포주기의 활성화, 그 중에서도 특히 $G_1$/S 이행에 관여하는 세포주기관련 단백질들은 암발생에 있어서 매우 중요한 역할을 하는 것으로 알려져 있다. $G_1$ 세포주기 관련 단백질 중의 하나인 cdk4 (cyclin dependent kinase 4)의 억제제로 알려져 있는 p16 유전자는 최근에 밝혀진 종양억제유전자중의 하나로서 MTS1 (multiple tumor suppressor 1)이라고도 불린다. p16 유전자는 지금까지 알려진 어느 종양관련 유전자보다도 유전자변이의 빈도가 높은 암억제유전자인데, 특히 비소세포폐암인 경우는 70% 이상의 세포주에서 p16 단백질의 발현이 없는 것으로 밝혀져 있어 p16 유전자는 비소세포폐암 발생에 매우 중요한 역할을 할 것이라고 알려져 있다. 본 연구에서는 비소세포폐암에서 p16을 이용한 유전자치료의 타당성을 입증하기 위하여 다음과 같은 연구를 시행하였다. 방 법 : p16이 결여된 비소세포폐암 세포주 (NCI-H441)에, 정상섬유아세포에서 총 RNA를 추출하여 역전사효소 및 DNA 중합효소반응으로 증폭된 p16 cDNA를 유핵세포 발현 vector인 pRC-CMV plasmid에 subcloning하여 구축된 pRC-CMV-p16 plasmid vector를 lipofectin을 이용하여 유전자 이입한 후, 단백질을 추출하여 Western blot 분석과 면역침전법으로 $G_1$ 세포주기관련 단백질의 변동을 관찰하고, colony 형성능을 비교함으로써 암억제효과를 확인하였다. 결 과 : p16이 유전자주입된 NCI-H441 세포주에서 p16과 cdk4가 복합체를 형성하고 있고 인산화 Rb가 대조 세포주에 비해 감소되어 있음을 확인할 수 있어, p16이 cdk4와 결합함으로써 cdk4에 의한 Rb의 인산화를 방해하고 이에 따른 $G_1$ 세포주기 정체에 의해 종양억제효과가 나타난다는 설명을 뒷받침할 수 있었다. Clonogenic assay 결과는 p16 유전자주입된 NCI-H441 세포주의 colony 형성능이 대조 세포주에 비하여 현격히 감소함을 관찰하였다. 결 론 : 이상의 결과로 p16(MTS1) 유전자를 p16 단백질을 발현하지 못하는 비소세포폐암 세포주에 주입할 경우, 주입한 유전자에서 생성되는 p16 단백질이 cdk와 결합하여 Rb 단백질의 인산화를 저하시켜 궁극적으로 암억제 효과를 일으킬 수 있음이 확인되었고, 이는 향후 비소세포폐암의 유전자치료에 있어서 p16 유전자의 이용 가능성을 확인한 기초자료가 된다고 생각된다.

• International Journal of Oral Biology
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• 제37권4호
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• pp.189-195
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• 2012

Resistance to the induction of apoptosis is a possible mechanism by which tumor cells can survive anti-neoplastic treatments. Melanoma is notoriously resistant to anti-neoplastic therapy. Previous studies have demonstrated focal adhesion kinase (FAK) overexpression in melanoma cell lines. Given its probable role in mediating resistance to apoptosis, many researchers have sought to determine whether the downregulation of FAK in melanoma cells would confer a greater sensitivity to anti-neoplastic agents. Genistein is a known inhibitor of protein-tyrosine kinase (PTK), which may attenuate the growth of cancer cells by inhibiting the PTK-mediated signaling pathway. This present study was undertaken to investigate the effect of genistein on the expression of FAK and cell cycle related proteins in the G361 melanoma cell line. Genistein was found to have a preferential cytotoxic effect on G361 melanoma cells over HaCaT normal keratinocytes. Genistein decreased the expression of 125 kDa phosphotyrosine kinase and the FAK protein in particular. Genistein treatment did not affect the expression of p53 in G361 cells in which p21 is upregulated. The expression of cyclin B and cdc2 was downregulated by genistein treatment. Taken together, our data indicate that genistein induces the decreased proliferation of G361 melanoma cells via the inhibition of FAK expression and regulation of cell cycle genes. This suggests that the use of genistein may be a viable approach to future melanoma treatments.

• 약학회지
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• 제46권1호
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• pp.18-23
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• 2002

Ailanthus altissima has been used to settle an upset stomach, to alleviate a fever and as an insecticide. We reported that the water extract of A. altissima induced apoptotic cell death in Jurkat T-acute Iymphoblastic leukemia cells. Here, we showed the dose-dependent inhibitions of cell viability by the extract, as measured by cell morphology. The cell cycle control genes are considered to play important roles in tumorigenesis. The purpose of the present study is also to investigate the effect of A. altissima on cell cycle progression and its molecular mechanism in the cells. The level of p21 protein was increased after treatment of the extract, whereas both Bcl-2 and Bax protein levels were not changed. These results suggest that A. altissima induces apoptotic cell death via p21-dependent signaling pathway in Jurkat cells which delete wild type p53. Gl checkpoint related gene products tested (cyclin D3, cyclin dependent kinase 4, retinoblastoma, E2Fl) were decreased in their protein levels in a dose-dependent manner after treatment of the extract Taken together, these results indicate that the increase of apoptotic cell death by A. altissima may be due to the inhibition of cell cycle in Jurkat cells.