• 제목/요약/키워드: K-Ras

검색결과 605건 처리시간 0.022초

Association between Ras association domain family 1A Promoter Methylation and Esophageal Squamous Cell Carcinoma: a Meta-analysis

  • Yang, Jian-Zhou;Ji, Ai-Fang;Wang, Jin-Sheng;Chen, Zhong-Yi;Wen, Shi Wu
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권9호
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    • pp.3921-3925
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    • 2014
  • RASSF1A has been reported to be a candidate tumor suppressor in esophageal squamous cell carcinoma (ESCC). However, the association between RASSF1A promoter methylation and ESCC remains unclear. Eligible studies were identified through searching PubMed, Medline, Web of Science, and the China National Knowledge Infrastucture database. Studies were pooled and odds ratios (ORs) with corresponding confidence intervals (CIs) were calculated. Funnel plots were also performed to evaluate publication bias. Twelve studies involving 859 cases and 675 controls were included in this meta-analysis. A significant association was observed between RASSF1A methylation and ESCC overall (OR = 11.7, 95% CI: 6.59-20.9, z=8.36, P<0.00001). Subgroup analysis showed that the OR for heterogeneous tissues was 5.35 (95% CI = 2.95-9.71) while for autologous tissues it was 16.0 (8.31-30.96). For patient sample size, the OR for the <50 subgroup was 9.92 (95% CI = 2.88-34.2) and for the 50 case group was 13.1 (95% CI = 6.59-25.91). The OR for a relationship between RASSF1A methylation and TNM stages was 0.27 (95% CI=0.10-0.77), whereas there were no significant differences in RASSF1A methylation in relation to gender and differentiation among ESCC cases. This meta-analysis suggests a significant association between RASSF1A methylation and ESCC.

Luteolin attenuates migration and invasion of lung cancer cells via suppressing focal adhesion kinase and non-receptor tyrosine kinase signaling pathway

  • Masraksa, Wuttipong;Tanasawet, Supita;Hutamekalin, Pilaiwanwadee;Wongtawatchai, Tulaporn;Sukketsiri, Wanida
    • Nutrition Research and Practice
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    • 제14권2호
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    • pp.127-133
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    • 2020
  • BACKGROUND/OBJECTIVES: Non-small cell lung cancer is mostly recognized among other types of lung cancer with a poor prognosis by cause of chemotherapeutic resistance and increased metastasis. Luteolin has been found to decrease cell metastasis. However, its underlying mechanisms remain unresolved. The objective of this study was to examine the effect (and its mechanism) of luteolin on the migration and invasion of human non-small cell lung cancer A549 cells. MATERIALS/METHODS: Cell viability was investigated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Wound healing and transwell assays were evaluated to assess migration and invasion, respectively. Western blot analysis and immunofluorescence were further performed to investigate the role of luteolin and its mechanisms of action. RESULTS: Administration with up to 40 μM luteolin showed no cytotoxic activity on lung cancer A549 cells or non-cancer MRC-5 cells. Additionally, luteolin at 20-40 μM significantly suppressed A549 cells' migration, invasion, and the formation of filopodia in a concentration-dependent manner at 24 h. This is similar with western blot analysis, which revealed diminished the phosphorylated focal adhesion kinase (pFAK), phosphorylated non-receptor tyrosine kinase (pSrc), Ras-related C3 botulinum toxin substrate 1 (Rac1), cell division control protein 42 (Cdc42), and Ras homolog gene family member A (RhoA) expression levels. CONCLUSIONS: Overall, our data indicate that luteolin plays a role in controlling lung cancer cells' migration and invasion via Src/FAK and its downstream Rac1, Cdc42, and RhoA pathways. Luteolin might be considered a promising candidate for suppressing invasion and metastasis of lung cancer cells.

Emerging Genomics Technologies in Nutritional Sciences: Applications to obesity and hypertension research

  • Mouss, Naima-Moustaid;Sumithra Urs;Kim, Suyeon;Heo, Young-Ran
    • 한국영양학회:학술대회논문집
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    • 한국영양학회 2002년도 춘계학술대회
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    • pp.29-41
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    • 2002
  • While the sequencing of several genomes was underway, several advanced techniques in genetics, molecular biology and protein chemistry emerged. Within the nutritional sciences, while the focus on nutrition education, epidemiology and public health aspects remains essential; it is crucial to incorporate the new advances in gene and protein discovery in nutritional studies. Nutrition is a discipline that has always integrated social, biochemical and physiological sciences from the studies at the molecule level to studies at the population level. For this reason, nutritionists are in a prime position to readily incorporate the current genomics approaches in nutrition research, All the available analytical techniques can and should be used in modern nutritional sciences. These include genetics, genomics, proteomics and metabolomics which also require integration and use of bioinformatics and computational methods for data analysis and management. These applications will be briefly reviewed with a primary focus on what the genomics and genetics approaches offer to nutritionists. We will use one of our research focus areas to illustrate uses of some of these applications in obesity-hypertension research. Our central hypothesis is that adipose tissue is an endocrine organ that plays a major role in obesity and related hypertension. We are primarily studying the renin angiotensin system (RAS). We provide evidence from our own studies and others for the paracrine as well as endocrine role of adipocyte-derived angiotensin II in adipocyte gene expression, adiposity and blood pressure regulation. Both cell culture studies as well as knockout and transgenic mice models are used to test our hypothesis. Genomics and proteomics technologies are currently developed to complement our physiological and molecular studies on the RAS and for a fine analysis of this system and its function in health and disease.

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Emerging Genomics Technologies in Nutritional Sciences : Applications to Obesity and Hypertension Research

  • Moustaid-Moussa;Sumithra Urs;Kim, Suyeon;Heo, Young-Ran
    • 한국영양학회:학술대회논문집
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    • 한국영양학회 2002년도 춘계 심포지움초록
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    • pp.598-603
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    • 2002
  • While the sequencing of several genomes was underway, several advanced techniques in genetics, molecular biology and protein chemistry emerged. Within the notritional sciences, while the focus on nutrition education, epidemiology and public health aspects remains essential; it is crucial to incorporate the new advances in gene and protein discovery in nutritional studies. Nutrition is a discipline that has always integrated social, biochemical and physiological sciences from the studies at the molecule level to studies at the population level. for this reason, nutritionists are in a prime position to readily incorporate the current genomics approaches in nutrition research. All the available analytical techniques can and should be used in modem nutritional sciences. These include genetics, genomics, proteomics and metabolomics which also require integration and use of bioinformatics and computational methods for data analysis and management. These applications will be briefly reviewed with a primary focus on what the genomics and genetics approaches offer to nutritionists. We will use one of our research focus areas to illustrate uses of some of these applications in obesity-hypertension research. Our central hypothesis is that adipose tissue is an endocrine organ that plays a major role in obesity and related hypertension. We are primarily studying the renin angiotensin system (RAS). We provide evidence from our own studies and others for the paracrine as well as endocrine role of adipocyte-derived angiotensin II in adipocyte gene expression, adiposity and blood pressure regulation. Both cell culture studies as well as knockout and transgenic mice models are used to test our hypothesis. Genomics and proteomics technologies are currently developed to complement our physiological and molecular studies on the RAS and for a fine analysis of this system and its function in health and disease.

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두경부 편평세포암종에서 전이와 예후 인자에 대한 연구 (CORRELATION OF METASTASIS AND PROGNOSTIC FACTORS IN SQUAMOUS CELL CARCINOMA OF HEAD AND NECK)

  • 서구종;유선열;김옥준;최홍란
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • 제28권1호
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    • pp.7-15
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    • 2002
  • The present study was carried out to evaluate the correlation of metastasis and prognostic factors in squamous cell carcinoma of head and neck. Examination was performed on a series of thirty-seven patients who were confirmed to squamous cell carcinoma and its lymphatic metastasis by pathologist. Correlations of metastasis and other factors such as angiogenesis, histologic grading, and p53 expression and ras oncogene were studied. The depth of tumors was around 1 to 27mm. Twenty cases were more than 10mm deep, of which seventeen cases were shown lymphatic metastasis. Total score of histologic grading including keratinization, nuclear atypia, growth pattern and intensity of inflammation was ranged from 5 to 10 points. Of these factors, nuclear atypia with intensity of inflammation, and nuclear atypia with growth pattern was correlated with nuclear atypia each. For angiogenesis, number of new-formed vessels were counted 13 to 58 each. Twenty-eight cases were shown to lymphatic metastasis. No correlation with histologic grading and lymphatic metastasis was found. The results of immunohistochemical staining for p53 and ras oncogene revealed that positive cases were 16 and 22, negative for 21 and 15 each. However, both were not correlated with histologic grading and lymphatic metastasis. These results were revealed that angiogenesis was not correlated with lymphatic metastasis of squamous cell carcinoma arising in head and neck. Nuclear atypia with intensity of inflammation and dysplasia with growth pattern were correlated with histologic grading, which suggested that more careful and adequate advice is needed for effective treatment.

하도 합류부의 정류.부정류해석에 따른 수리학적 변화 특성 분석 (Hydraulic Behavior and Characteristic Analysis by Steady & Unsteady Flow Analysis of Natural Stream)

  • 안승섭;임동희;박노삼;곽태화
    • 한국환경과학회지
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    • 제17권9호
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    • pp.957-968
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    • 2008
  • The purpose of this study is to analyze the characteristics of hydraulic behavior of the natural channel flow according to the temporal classification mode, and thus propose the hydraulic analysis method for future channel design. For analysis, the temporal flow characteristics of the channel section was divided into the steady flow and the unsteady flow. For hydraulic analysis, the HEC-RAS model, which is a one-dimensional numerical analysis model, and the SMS-RAM2 model, which is a two-dimensional model, were used and the factors used for analysis of hydraulic characteristics were flood elevation and flow rate. The flow state was analyzed on the basis of the one-dimensional steady flow and unsteady flow for review. In the unsteady flow analysis the flow rate changed by $(-)0.16%{\sim}(+)0.26%$, and the flood elevation varied by $(-)0.35%{\sim}(+)0.51%$ as compared to the values in the steady flow analysis. Given these results, in the one-dimensional flow analysis based on the unsteady flow the flood elevation and flow rate were greater than when the analysis was done on the basis of the steady flow. The flow state was analyzed on the basis of the two-dimensional steady flow and unsteady flow. In the unsteady flow analysis the flow rate varied by $(-)0.16%{\sim}(+)1.08%$, and the flood elevation changed by $(-)0.24%{\sim}(+)0.41%$ as compared to the values in the steady flow analysis. Given these analysis results, in the two dimensional flow analysis based on the unsteady flow, the flood elevation and flow rate were greater than when the analysis was done on the basis of the steady flow.

Characterization of Effective Capacity in Antenna Selection MIMO Systems

  • Lari, Mohammad;Mohammadi, Abbas;Abdipour, Abdolali;Lee, Inkyu
    • Journal of Communications and Networks
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    • 제15권5호
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    • pp.476-485
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    • 2013
  • In this paper, the effective capacity of a multiple-input multiple-output (MIMO) system in two different cases with receive antenna selection (RAS) and transmit antenna selection (TAS) schemes is investigated. A closed-form solution for the maximum constant arrival rate of this network with statistical delay quality of service (QoS) constraint is extracted in the quasi-static fading channel. This study is conducted in two different cases.When channel state information (CSI) is not available at the MIMO transmitter, implementation of TAS is difficult. Therefore, RAS scheme is employed and one antenna with the maximum instantaneous signal to noise ratio is chosen at the receiver. On the other hand, when CSI is available at the transmitter, TAS scheme is executed. In this case, one antenna is selected at the transmitter. Moreover, an optimal power-control policy is applied to the selected antenna and the effective capacity of the MIMO system is derived. Finally, this optimal power adaptation and the effective capacity are investigated in two asymptotic cases with the loose and strict QoS requirements. In particular, we show that in the TAS scheme with the loose QoS restriction, the effective capacity converges to the ergodic capacity. Then, an exact closed-form solution is obtained for the ergodic capacity of the channel here.

국내 지방하천의 유사량과 하상변동 특성에 관한 연구 (A Study of Sediment Discharge and Bed Change Characteristics of the Local Rivers in Korea)

  • 손호근;이정식;신사철;문창건
    • 한국지반환경공학회 논문집
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    • 제15권6호
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    • pp.31-39
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    • 2014
  • 본 연구는 하천 계획수립 및 활용을 위하여 국내 하천을 대상으로 적합한 유사량 추정공식과 장 단기 하상변동을 정량적으로 제시한다. 산지 및 도시하천을 대상으로 유사특성을 분석하고, 총유사량 과 장 단기 하상변동을 검토하기 위하여 기존의 유사량 추정공식과 HEC-RAS 4.1 모형 및 CCHE2D 모형을 적용하였다. 본 연구의 수행으로 인해 얻어진 결과를 요약하면 다음과 같다. 첫째, 수정 Einstein 공식을 적용하여 추정한 총유사량이 해당 하천에 가장 적합한 것으로 판단되었다. 둘째, 대상하천의 중 장기적인 하도관리를 위하여 수위-유량 관계곡선, 부유사량-유량 관계곡선과 총유사량-유량 관계곡선을 제시하였다. 셋째, 단기하상 변동 분석에서는 산지하천이 도시하천보다 하상변동이 크게 발생하였으며, 장기하상 분석에서 도시하천은 현재 안정하상에 도달한 것으로 나타났다.

Differential Display Analysis of 2,3,7,8-Tetrachlorodibenzo-p-dioxin Identified Induction of Ras-related Nuclear Protein Binding Protein2 (RanBP2) Gene

  • Kim, Dong-Hak;Lim, Young-Ran;Park, Hyoung-Goo;Kim, Beom-Joon;Chun, Young-Jin
    • Toxicological Research
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    • 제25권1호
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    • pp.35-40
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    • 2009
  • TCDD (2,3,7,8-tetrachlorodibenzo-p-dioxin) and related halogenated aromatic hydrocarbons elicit a diverse spectrum of biochemical and toxic responses in laboratory animals and mammalian cells in culture. Toxicity and carcinogenicity of TCDD is well established but the molecular mechanism is still poorly understood. Here, we found the noble responsive genes to TCDD using the differential display analysis. Treatment of HepG2 cells with TCDD showed a significantly different mRNA expression pattern from the untreated cells in differential display analysis. The differentially displayed bands were isolated and used as probes in dot blot and Northern blot analyses. Of thirty-five isolated differentially displayed bands, only two bands were confirmed as positive in dot blot and Northern blot analyses. The nucleotides sequences of these clones were analyzed and the search of Genebank database revealed that one clone is highly homologous with RanBP2 (Ras-related nuclear protein binding protein2; 92%) and the other is an unknown gene. RanBP2 is a nucleoporin with SUMO E3 ligase activity that functions in both nucleocytoplasmic transport and mitosis and its role as a novel tumor suppressor has been recently proposed. Thus, these results may suggest the clue elucidating the toxic mechanism of TCDD through RanBP2.

Diamond-Like Carbon Films Deposited by Pulsed Magnetron Sputtering System with Rotating Cathode

  • Chun, Hui-Gon;You, Yong-Zoo;Nikolay S. Sochugov;Sergey V. Rabotkin
    • 한국표면공학회지
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    • 제36권4호
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    • pp.296-300
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    • 2003
  • Extended cylindrical magnetron sputtering system with rotating 600-mm long and 90-mm diameter graphite cathode and pulsed power supply voltage generator were developed and fabricated. Time-dependent Langmuir probe characteristics as well as carbon films thickness were measured. It was shown that ratio of ions flux to carbon atoms flux for pulsed magnetron discharge mode was equal to $\Phi_{i}$ $\Phi$sub C/ = 0.2. It did not depend on the discharge current in the range of $I_{d}$ / = 10∼60 A since both the plasma density and the film deposition rate were found approximately proportional to the discharge current. In spite of this fact carbon film structure was found to be strongly dependent on the discharge current. Grain size increased from 100 nm at $I_{d}$ = 10∼20 A to 500 nm at $I_{d}$ = 40∼60 A. To deposit fine-grained hard nanocrystalline or amorphous carbon coating current regime with $I_{d}$ = 20 A was chosen. Pulsed negative bias voltage ($\tau$= 40 ${\mu}\textrm{s}$, $U_{b}$ = 0∼10 ㎸) synchronized with magnetron discharge pulses was applied to a substrate and voltage of $U_{b}$ = 3.4 ㎸ was shown to be optimum for a hard carbon film deposition. Lower voltages were not sufficient for amorphization of a growing graphite film, while higher voltages led to excessive ion bombardment and effects of recrystalization and graphitization.