• 제목/요약/키워드: Tumor suppressor protein p53

검색결과 99건 처리시간 0.022초

Promoter Methylation of CDKN2A, $RAR{\beta}$, and RASSF1A in Non-Small Cell Lung Carcinoma: Quantitative Evaluation Using Pyrosequencing

  • Lee, Jung Uee;Sul, Hae Joung;Son, Ji Woong
    • Tuberculosis and Respiratory Diseases
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    • 제73권1호
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    • pp.11-21
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    • 2012
  • Background: While qualitative analysis of methylation has been reviewed, the quantitative analysis of methylation has rarely been studied. We evaluated the methylation status of CDKN2A, $RAR{\beta}$, and RASSF1A promoter regions in non-small cell lung carcinomas (NSCLCs) by using pyrosequencing. Then, we evaluated the association between methylation at the promoter regions of these tumor suppressor genes and the clinicopathological parameters of the NSCLCs. Methods: We collected tumor tissues from a total of 53 patients with NSCLCs and analyzed the methylation level of the CDKN2A, $RAR{\beta}$, and RASSF1A promoter regions by using pyrosequencing. In addition, we investigated the correlation between the hypermethylation of CDKN2A and the loss of $p16^{INK4A}$ immunoexpression. Results: Hypermethylation of CDKN2A, $RAR{\beta}$, and RASSF1A promoter regions were 16 (30.2%), 22 (41.5%), and 21 tumors (39.6%), respectively. The incidence of hypermethylation at the CDKN2A promoter in the tumors was higher in undifferentiated large cell carcinomas than in other subtypes (p=0.002). Hyperrmethylation of CDKN2A was significantly associated with $p16^{INK4A}$ immunoexpression loss (p=0.045). With regard to the clinicopathological characteristics of NSCLC, certain histopathological subtypes were found to be strongly associated with the loss of $p16^{INK4A}$ immunoexpression (p=0.016). Squamous cell carcinoma and undifferentiated large cell carcinoma showed $p16^{INK4A}$ immunoexpression loss more frequently. The Kaplan-Meier survival curves analysis showed that methylation level and patient survival were barely related to one another. Conclusion: We quantitatively analyzed the promoter methylation status by using pyrosequencing. We showed a significant correlation between CDKN2A hypermethylation and $p16^{INK4A}$ immunoexpression loss.

Structural characterization of As-MIF and hJAB1 during the inhibition of cell-cycle regulation

  • Park, Young-Hoon;Jeong, Suk;Ha, Ki-Tae;Yu, Hak Sun;Jang, Se Bok
    • BMB Reports
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    • 제50권5호
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    • pp.269-274
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    • 2017
  • The biological activities of macrophage migration inhibitory factor (MIF) might be mediated through a classical receptor-mediated or non-classical endocytic pathway. JAB1 (C-Jun activation domain-binding protein-1) promotes the degradation of the tumor suppressor, p53, and the cyclin-dependent kinase inhibitor, p27. When MIF and JAB1 are bound to each other in various intracellular sites, MIF inhibits the positive regulatory effects of JAB1 on the activity of AP-1. The intestinal parasite, Anisakis simplex, has an immunomodulatory effect. The molecular mechanism of action of As-MIF and human JAB1 are poorly understood. In this study, As-MIF and hJAB1 were expressed and purified with high solubility. The structure of As-MIF and hJAB1 interaction was modeled by homology modeling based on the structure of Ace-MIF. This study provides evidence indicating that the MIF domain of As-MIF interacts directly with the MPN domain of hJAB1, and four structure-based mutants of As-MIF and hJAB1 disrupt the As-MIF-hJAB1 interaction.

Overexpression of Anti-apoptotic Molecules and Sax Translocation to Mitochondria by Pharbitis Nil Extracts in AGS

  • Ko Seong-Gyu
    • 동의생리병리학회지
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    • 제18권6호
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    • pp.1843-1849
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    • 2004
  • Conventional medicines have usually sorted to a number of treatments such asoperation, radiotherapy, and chemotherapy. The existing anti-cancer agents, designed to eradicate cancer cells, have strong toxicities, also with leading to harmful side effects. Recently, a number of researches on natural products have been actively carried out in efforts to develop new treatments that can decrease side effects or increase anti-cancer effects. We performed this study to understand the molecular basis underlying the antitumor effects of Pharbitis nil, and Plantago asiatica, which have been used for herbal medicinal treatments against cancers in East Asia. We analyzed the effects of these medicinal herbs on proliferation and on expression of cell growth/apoptosis related molecules, with using an AGS gastric cancer cell line. The treatment of Pharbitis nil dramatically reduced cell viabilities in a dose and time-dependent manner, but Plantago asiatica didn't. FACS analysis and Annexin V staining assay also showed that Pharbitis nil induce apoptotic cell death of AGS. Expression analyses via RT-PCR and Western blots revealed that Pharbitis nil didn't increase expression of the p53 and its downstream effector p21/sup wafl/, and that the both increased expression of apoptosis related Sax and cleavage of active caspase-3 protein. We also confirmed the translocation of Sax to mitochondria. Collectively, our data demonstrate that Pharbitis nilinduce growth inhibition and apoptosis of human gastric cancer cells, and these effects are correlated with down- and up-regulation of growth-regulating apoptotic and tumor suppressor genes, respectively.

인체 방광암 및 백혈병세포에서 genistein에 의한 세포주기 G2/M arrest 유발에 관한 연구 (Induction of G2/M Arrest of the Cell Cycle by Genistein in Human Bladder Carcinoma and Leukemic Cells)

  • 김의겸;명유호;송관성;이기홍;류충호;최영현
    • 생명과학회지
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    • 제16권4호
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    • pp.589-597
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    • 2006
  • 본 연구에서는 T24 인체방광암 및 U937 백혈병 세포의 증식에 미치는 genistein의 영향을 조사 하였다. Genistein이 처리된 T24 및 U937 세포는 처리 농도 의존적으로 세포의 증식이 현저히 감소되었으며 심한 형태적 변형이 동반되었으나, U937 세포에서 보다 높은 감수성을 보였다. 이러한 T24 및 U937 세포의 증식억제 및 형태 변형은 G2/M기의 세포주기 억제 및 apoptosis 유발과 연관성이 있음을 flow cytometry를 이용한 세포주기의 분석을 통하여 확인하였다. T24 세포에서 genistein에 의한 G2/M arrest는 cyclin A, cyclin B1 및 Cdc25C 등의 단백질 발현 감소와 연관성이 있었으나, 종양억제 유전자 p53 및 Cdk inhibitor p21의 발현에는 큰 변화가 없었다. U937 세포에서 genistein에 의한 G2/M arrest는 cyclin B1 및 p53 비의존적인 p21의 발현 증가와 연관성이 있었다. 이상의 결과들은 현재까지 거의 연구가 진행된 바 없는 인체방광암 및 백혈병 세포에서 genistein의 항암작용을 이해하는데 중요한 자료가 될 것이고 나아가 genistein을 포함한 그와 유사한 항암제 후보물질들의 연구에 있어서 기초 자료로서 사용될 수 있을 것으로 생각된다.

봉독약침액(蜂毒藥鍼液)에 의한 인체유방암세포(人體乳房癌細胞)의 성장억제(成長抑制) 및 세포사(細胞死)에 관한 연구(硏究) (Induction of the Growth Inhibition and Apoptosis by Beevenom in Human Breast Carcinoma MCF-7 Cells)

  • 여성원;서정철;최영현;장경전
    • Journal of Acupuncture Research
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    • 제20권3호
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    • pp.45-62
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    • 2003
  • Objective : To examine the effects of Beevenom on the cell proliferation of human breast carcinoma cell line MCF-7, we performed various experiments such as does-dependent effect of Beevenom on cell proliferation and viability, morphological changes, and alterations of apoptosis/cell cycle-regulatory gene products. Methods : Beevenom induced cell viability and proliferation of MCF-7 cells in a concentration-dependent manner. The anti-proliferative effect by Beevenom treatment in MCF-7 cells was associated with morphological changes such as membrance shrinking and cell rounding up. Results : Beevenom induced apoptotic cell death in a concentration-dependent manager, which was associated with degradation of ${\beta}$-catenin, an apoptotic target protein. Beevenom induced the Bax expressions, a pro-apoptotic gene, both in protein and mRNA levels, however, the levels of Bcl-$X_{S/L}$ expression, an anti-apoptotic gene, were down-regulated in Beevenom-treated cells. Western blot analysis and RT-PCT data revealed that the levels of cyclin of B1 protein and cyclin E mRNA were reduced by Beevenom treatment in MCF-7 cells, respectively, where as the expression of tumor suppressor p53 and cyclin dependent kinase inhibitor p21 mRNA were markedly increased in a concentration-dependent fashion. Conclusions : Taken together, these findings suggest that Beevenom induced inhibition of human breast cancer cell proliferation is associated with the induction of apoptotic cell death and Beevenom may have therapeutic potential in human breast cancer.

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Prognostic Involvement of Nucleophosmin Mutations in Acute Myeloid Leaukemia

  • Shahab, Sadaf;Shamsi, Tahir Sultan;Ahmed, Nuzhat
    • Asian Pacific Journal of Cancer Prevention
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    • 제14권10호
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    • pp.5615-5620
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    • 2013
  • Nucleophosmin (NPM1) is a protein of highly conserved nature which works as a molecular chaperone and is mostly found in nucleoli. NPM also involved in the maturation of preribosomes and duplication of centrosomes. Furthermore, it is also active in control and regulation of the ARF-p53 tumor suppressor pathway. A high rate of incidence and prognostic involvement is reported by various authors in AML patients. In AML it behaves as a favorable prognostic marker. NPM mutations are more frequently associated with normal-karyotype AML and are usually absent in patients having abnormal or poor cytogenetic. NPM mutations are not frequent in other hematopoietic tumors. Two main types of mutations have been described to date. Both of these cause abnormal cytoplasmic localization of NPM1. Their high incidence rate in normal karyoptype and their favorable nature m ake those mutations hot spot or front face mutations which should be checked before treatment starts.

A Fermented Ginseng Extract, BST204, Inhibits Proliferation and Motility of Human Colon Cancer Cells

  • Park, Jong-Woo;Lee, Jae-Cheol;Ann, So-Ra;Seo, Dong-Wan;Choi, Wahn-Soo;Yoo, Young-Hyo;Park, Sun-Kyu;Choi, Jung-Young;Um, Sung-Hee;Ahn, Seong-Hoon;Han, Jeung-Whan
    • Biomolecules & Therapeutics
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    • 제19권2호
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    • pp.211-217
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    • 2011
  • Panax ginseng CA Meyer, a herb from the Araliaceae, has traditionally been used as a medicinal plant in Asian countries. Ginseng extract fermented by ginsenoside-${\beta}$-glucosidase treatment is enriched in ginsenosides such as Rh2 and Rg3. Here we show that a fermented ginseng extract, BST204, has anti-proliferative and anti-invasive effects on HT-29 human colon cancer cells. Treatment of HT-29 cells with BST204 induced cell cycle arrest at $G_1$ phase without progression to apoptosis. This cell cycle arrest was accompanied by up-regulation of tumor suppressor proteins, p53 and p21$^{WAF1/Cip1}$, down-regulation of the cyclin-dependent kinase/cyclins, Cdk2, cyclin E, and cyclin D1 involved in $G_1$ or $G_1/S$ transition, and decrease in the phosphorylated form of retinoblastoma protein. In addition, BST204 suppressed the migration of HT-29 cells induced by 12-O-tetradecanoylphorbol-13-acetate, which correlated with the inhibition of metalloproteinase-9 activity and extracellular signal-regulated kinase activity. The effects of BST204 on the proliferation and the invasiveness of HT-29 cells were similar to those of Rh2. Taken together, the results suggest that fermentation of ginseng extract with ginsenoside-${\beta}$-glucosidase enhanced the anti-proliferative and the anti-invasive activity against human colon cancer cells and these anti-tumor effects of BST204 might be mediated in part by enriched Rh2.

미세소관-손상 항암제 처리에 의한 세포주기의 정지 및 에폽토시스 유도 (Microtubule-damaging Chemotherapeutic Agent-mediated Mitotic Arrest and Apoptosis Induction in Tumor Cells)

  • 전도연;김영호
    • 생명과학회지
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    • 제26권3호
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    • pp.376-386
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    • 2016
  • 에폽토시스에 의한 세포자멸사는 암세포에 대한 항암제 효능의 핵심적 기전이다. 항암제의 대표적인 두 종류로 알려진 DNA-손상 약제(DNA-damaging agents, DDAs)와 미세소관-손상 약제(microtubule-damaging agents, MDAs)가 암세포에 야기하는 초기 항암신호전달 기전은 다르지만, 최종적으로는 대부분 미토콘드리아 의존-에폽토시스를 통해 암세포를 사멸시킨다. 한편, DDAs에 의한 에폽토시스 유도에는 wild-type 종양억제 단백질 p53의 역할이 매우 중요하다. 그러나 인체 암의 약 50% 이상이 p53유전자의 돌연변이 때문에 종양억제 단백질로서의 p53 기능이 불활성화 되어 있다. 따라서 p53과 무관하게 에폽토시스를 유도할 수 있는 MDAs를 이용한 항암치료는 돌연변이 p53을 지닌 암세포에 대해 유리한 화학요법으로 이해된다. 최근 본 연구진은 인체 급성 백혈병 세포주인 Jurkat T 세포를 모델로 하여, MDAs (nocodazole, 17-α-estradiol, 혹은 2-methoxyestradiol)의 항암작용과 관련된 세포주기 정지 및 에폽토시스 유도 기전을 구명하였다. 그 결과, Jurkat T 세포를 MDAs로 처리할 경우, 유사분열방추사의 결함에 의한 세포주기(전중기, prometaphase) 정지, 장시간에 걸친 Cdk1의 활성화, 활성화된 Cdk1에 의한 에폽토시스 조절인자들(Bcl-2, Bcl-xL, Mcl-1 및 Bim)의 인산화, 이에 따른 Bak 활성화, 미토콘드리아막 손상 및 카스파아제 연쇄 활성화에 의해 에폽토시스가 유도됨을 밝혔다. 또한 동일한 MDA 처리 조건하에서 Bcl-2 혹은 Bcl-xL의 과발현시켜 에폽토시스 진행을 차단할 경우, Jurkat T 세포는 약제처리 후에 전중기 정지된 4N 상태에 도달하지만, 이어서 유사분열 불이행(mitotic slippage) 및 내재복제(endoreduplication)가 진행되어 다배수체들(polyploids; 8N, 16N)을 생성하게 됨을 확인하였다. 이러한 결과는 MDAs처리에 따른 다배수체들의 생성을 차단하는 세포 내 기전으로서, 전중기 정지된 4N 세포의 에폽토시스에 의한 제거가 매우 중요함을 보여준다. 특히, 다배수체는 유전적으로 매우 불안정하여 암세포의 항암제 내성 획득 및 암 재발과 직접 연관되는 것으로 알려져 있으므로, 에폽토시스 기전에 결함이 있는 암세포를 대상으로 MDAs를 이용한 항암 화학요법을 시행할 경우에는 다배수체 세포의 생성을 차단하기 위한 새로운 수단이 반드시 병행되어야 할 것으로 사료된다.

HepG2 인체간암세포의 세포주기조절인자 발현에 미치는 sulforaphane의 영향 (Modulation of Cell Cycle Regulators by Sulforaphane in Human Mepatocarcinoma HepG2 Cells)

  • 배송자;김기영;유영현;최병태;최영현
    • 생명과학회지
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    • 제16권7호
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    • pp.1235-1242
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    • 2006
  • 브로콜리를 포함한 십자화과 식물에서 glucoraphanin의 가수분해를 통해 생성되는 isothiocyanate의 일종인 sulforaphane은 역학적 조사를 포함한 다양한 선행 연구에서 강력한 암예방 효과를 가지는 것으로 알려져 있다. 항암효과에 관한 최근 연구 결과에 따르면 sulforaphane은 다양한 인체암세포의 증식을 억제하고 apoptosis를 유발할 수 있는 것으로 알려지고 있으나, 정확한 분자생물학적 기전은 밝혀져 있지 않은 상태이다. 본 연구에서는 sulforaphane의 항암작용 기전을 조사하기 위하여 HepG2 인체간암세포의 증식에 미치는 sulforaphane의 영 향을 조사하였다. Sulforaphane의 처리에 의한 HepG2 세포의 증식억제 및 형태적 변형은 세포주기 G2/M arrest 및 apoptosis 유발과 밀접한 관련이 있음을 알 수 있었다. RT-PCR 및 Western blot 분석 결과, sulforaphane 처리에 의하여 cyclin A 및 cyclin B1, Cdc2의 발현이 단백질 수준에서 선택적으로 저하되었으며, 종양억제 유전자 p53 및 Cdk inhibitor p21의 발현은 전사 및 번역 수준에서 sulforaphane 처리 농도 의존적으로 증가되었다. Sulforaphane의 항암 기전을 규명하기 위해서는 더 많은 연구가 부가적으로 필요하겠지만, 본 연구의 결과들에 의하면 sulforaphane은 강력한 인체암세포의 증식 억제 및 항암작용이 있을 것을 시사하여 준다고 할 수 있다.

산두근 추출물이 인체폐암세포의 COX-2 발현 및 PGE2 생성에 미치는 영향 (Antiproliferative Effect of RST Associated with the Inhibition of Cyclooxygenase-2 Expression and Prostaglandin E2 Release in Human Lung Carcinoma Cells)

  • 김강태;엄현섭;지규용
    • 동의생리병리학회지
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    • 제21권4호
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    • pp.907-915
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    • 2007
  • In this study the effect of water extract of Sophora tonkinensis Gapnep (RST) was investigated on the growth of human lung carcinoma A549 cells. Exposure of A549 cells to RST resulted in the growth inhibition in a dose-dependent manner as measured by MTT assay. The antiproliferative effect by RST treatment in A549 cells was associated with morphological changes such as membrane shrinking and cell rounding up. RST treatment did not induce the cell cycle arrest and the levels of tumor suppressor p53 as well as cyclin-dependent kinase inhibitor p21(WAF1/CIP1). It was found that RST treatment decreased the levels of cyclooxygenase (COX) -2 mRNA and protein expression without significant changes in the expression of COX-1 and inducible nitric oxide synthase (iNOS), which was correlated with a decrease in prostaglandin E2 (PGE2) synthesis. RST treatment also slightly inhibited the levels of human telomerase reverse transcriptase (hTERT) mRNA and protein expression, and the activity of telomerase. Taken together, these findings suggested that RST-induced inhibition of human lung carcinoma A549 cell growth was aoosciated with the inhibition of COX-2 expression and PGE2 production. These results provided important new insights into the possible molecular mechanisms of the anti-cancer activity of RST.