• 제목/요약/키워드: Small G protein

검색결과 399건 처리시간 0.026초

Knockdown of Med19 Suppresses Proliferation and Enhances Chemo-sensitivity to Cisplatin in Non-small Cell Lung Cancer Cells

  • Wei, Ling;Wang, Xing-Wu;Sun, Ju-Jie;Lv, Li-Yan;Xie, Li;Song, Xian-Rang
    • Asian Pacific Journal of Cancer Prevention
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    • 제16권3호
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    • pp.875-880
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    • 2015
  • Mediator 19 (Med19) is a component of the mediator complex which is a coactivator for DNA-binding factors that activate transcription via RNA polymerase II. Accumulating evidence has shown that Med19 plays important roles in cancer cell proliferation and tumorigenesis. The involvement of Med19 in sensitivity to the chemotherapeutic agent cisplatin was here investigated. We employed RNA interference to reduce Med19 expression in human non-small cell lung cancer (NSCLC) cell lines and analyzed their phenotypic changes. The results showed that after Med19 siRNA transfection, expression of Med19 mRNA and protein was dramatically reduced (p<0.05). Meanwhile, impaired growth potential, arrested cell cycle at G0/G1 phase and enhanced sensitivity to cisplatin were exhibited. Apoptosis and caspase-3 activity were increased when cells were exposed to Med19 siRNA and/or cisplatin. The present findings suggest that Med19 facilitates tumorigenic properties of NSCLC cells and knockdown of Med19 may be a rational therapeutic tool for lung cancer cisplatin sensitization.

폐암세포에 p16 (MTS1) 유전자 주입후 암생성능의 변화 및 세포주기관련 단백질의 변동에 관한 연구 (The Change of Cell-cycle Related Proteins and Tumor Suppressive Effect in Non-small Cell Lung Cancer Cell Line after Transfection of p16(MTS1) Gene)

  • 김영환;김재열;유철규;한성구;심영수;이계영
    • 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.

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Association between PCR-RFLP of Melatonin Receptor 1a Gene and High Prolificacy in Small Tail Han Sheep

  • Chu, M.X.;Ji, C.L.;Chen, G.H.
    • Asian-Australasian Journal of Animal Sciences
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    • 제16권12호
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    • pp.1701-1704
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    • 2003
  • Melatonin regulates circadian rhythms and reproduction changes in seasonally reproductive mammals through binding to high-affinity, G-protein-coupled receptors. Small Tail Han sheep that has significant characteristics of high prolificacy and nonseasonal ovulatory activity is an excellent local sheep breed in P. R. China. The exon 2 of the ovine melatonin receptor 1a (MTNR1A) gene was amplified and a uniform fragment of 824 bp was obtained in 150 ewes of Small Tail Han sheep. The 824 bp PCR product was digested with restriction endonucleases Mnl I and Rsa I, and genetic polymorphism was detected by PCR-RFLP. Polymorphic Mnl I site was detected at base position 605 of the exon 2 of the MTNR1A gene. There were two kinds of genotypes in Small Tail Han sheep, AB (303 bp, 236 bp/67 bp) and BB (236 bp/67 bp, 236 bp/67 bp). The results indicated that genotype AA (303 bp, 303 bp) at Mnl I-RFLP site did not exist in non-seasonal estrous Small Tail Han sheep, which suggested that there was an association between genotype AA (303 bp, 303 bp) and reproductive seasonality in sheep. Polymorphic Rsa I site was detected at base position 604 of the exon 2 of the MTNR1A gene. Three kinds of genotypes were found in Small Tail Han sheep, AA (290 bp, 290 bp), AB (290 bp, 267 bp/23 bp) and BB (267 bp/23 bp, 267 bp/23 bp). Least squares means of litter size in the first parity and the second parity for genotype AA (290 bp, 290 bp) at Rsa I-RFLP site were 0.43 and 1.06 more than those for genotype AB (290 bp, 267 bp/23 bp) in Small Tail Han sheep.

중북부지역에서 재배한 소립 검정콩의 품질 및 이화학 특성 (Quality and Physicochemical Characteristics of Small Black Soybean Cultivar Cultivated in the North-central Region)

  • 김현주;정건호;이지혜;이병원;이유영;김성국;이병규;우관식
    • 한국식품영양학회지
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    • 제31권6호
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    • pp.792-801
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    • 2018
  • Proximate compositions, quality and physicochemical characteristics of small black soybean cultivar, cultivated in the north-central region of South Korea with different seeding periods, were evaluated. Proximate compositions, chromaticity, water binding capacity, water solubility index, swelling power, and antioxidant properties were significantly different among cultivars and different seeding periods. Moisture, crude ash, fat, protein, and carbohydrate contents of small black soybean cultivar were 5.53~6.69, 5.47~6.54, 15.38~19.14, 34.17~40.26, and 32.04~36.85 g/100 g, respectively. Lightness, redness and yellowness were 35.60~38.61, -0.02~0.07 and -0.56~-0.13, and water binding capacity, water solubility index and swelling power were 84.48~148.31, 46.65~54.89 and 29.87~35.12%, respectively. Total polyphenol contents of first, second, and third seedings on small black soybean cultivar were 10.40~15.48, 9.86~14.85 and 8.61~15.39 mg GAE/g; total flavonoid contents were 5.81~7.25, 5.81~7.34 and 5.52~7.64 mg CE/g, respectively. DPPH radical scavenging activity was 4.55~7.86, 3.99~8.79, and 3.74~9.43 mg TE/g, and ABTS radical scavenging activity was 9.32~12.90, 8.64~13.39, and 8.51~14.35 mg TE/g, respectively. Phenol compound of Tawonkong and Socheong cultivars decreased with delay of seeding periods. Radical scavenging activity of Socheong and Jununi cultivars decreased with delay of seeding periods, but Socheong 2 and Socheongja cultivars increased. In the study, phenol compound and radical scavenging activity of small black soybean cultivar were different, depending on cultivars and seeding periods.

Comparison of the Efficiency of Absorbed Nitrogen Use from Different Protein Sources in Diets Having Similar Amino Acid Balance

  • Lee, K.U.;Boyd, R.D.;Austic, R.E.;Ross, D.A.;Han, In K.
    • Asian-Australasian Journal of Animal Sciences
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    • 제11권6호
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    • pp.725-731
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    • 1998
  • Nine crossbred female pigs fitted with the bladder catheters were used to investigate the effects of dietary protein form on the efficiency of absorbed nitrogen for nitrogen retention in growing pigs. Combinations of the main protein sources were corn-soybean meal (CSM; slow + slow absorption rate form), corn-hydrolyzed casein (CAS; slow + rapid absorption rate form) and corn-porcine plasma (CPL; slow + intermediate absorption rate form). All experimental diets were formulated to be isonitrogenous (CP 11%) and isocaloric (3.5 Mcal/kg) and synthetic amino acids were added to the diet as required to maintain an equivalent amino acid profile among diets. Fecal digestibility of nitrogen was not different among treatments (p > 0.10). Ingested nitrogen was absorbed with an apparent efficiency of 82% to 84%. Mean nitrogen retention in pigs fed the CSM diet was as high as for pigs fed the CPL diet (0.74 g N/kg $BW^{0.75}$ per d), which was higher than the N retention rate in pigs fed CAS diet (0.68 g/kg $BW^{0.75}$ per d; P < 0.05). Apparent biological values (ABV = 100 ${\times}$ N retention/absorbed nitrogen) were 63.3%, 58.0% and 61.6% for CSM, CAS, and CPL groups, respectively (p < 0.05). There was no difference in mean energy digestibility among treatments. The efficiency of absorbed lysine utilization was significantly different among treatments (p < 0.05). Pigs fed the CAS diet were inferior to counterparts on the other diets in utilizing absorbed lysine. The ratios of free (and small peptide-bound) to protein-bound amino acids in CSM diet differed considerably from the CAS diet. This may affect the efficiency of amino acids utilization for nitrogen retention if hydrolyzed and intact amino acid pools reach the blood at different times.

Expression in Escherichia coli of a Putative Human Acetohydroxyacid Synthase

  • Duggleby, Ronald G.;Kartikasari, Apriliana E.R.;Wunsch, Rebecca M.;Lee, Yu-Ting;Kil, Mee-Wha;Shin, Ju-Young;Chang, Soo-Ik
    • BMB Reports
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    • 제33권3호
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    • pp.195-201
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    • 2000
  • A human gene has been reported that may encode the enzyme acetohydroxyacid synthase. Previously this enzyme was thought to be absent from animals although it is present in plants and many microorganisms. In plants, this enzyme is the target of a number of commercial herbicides and the use of these compounds may need to be reassessed if the human enzyme exists and proves to be susceptible to inhibition. Here we report the construction of several plasmid vectors containing the cDNA sequence for this protein, and their expression in Escherichia coli. High levels of expression were observed, but most of the protein proved to be insoluble. The small amounts of soluble protein contained little or no acetohydroxyacid synthase activity. Attempts to refold the insoluble protein were successful insofar as the protein became soluble. However, the refolded protein did not gain any acetohydroxyacid synthase activity. In vivo complementation tests of an E. coli mutant produced no evidence that the protein is active. Incorrect folding, or the lack of another subunit, may explain the data but we favor the interpretation that this gene does not encode an acetohydroxyacid synthase.

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Induction of cytoprotective autophagy by morusin via AMP-activated protein kinase activation in human non-small cell lung cancer cells

  • Park, Hyun-Ji;Park, Shin-Hyung
    • Nutrition Research and Practice
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    • 제14권5호
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    • pp.478-489
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    • 2020
  • BACKGROUND/OBJECTIVES: Morusin, a marker component of Morus alba L., possesses anti-cancer activity. The objective of this study was to determine autophagy-inducing effect of morusin in non-small cell lung cancer (NSCLC) cells and investigate the underlying mechanism. SUBJECTS/METHODS: Autophagy induction and the expression of autophagy-related proteins were analyzed by LC3 immunofluorescence and western blot, respectively. The role of autophagy and AMP-activated protein kinase (AMPK) was determined by treating NSCLC cells with bafilomycin A1, an autophagy inhibitor, and compound C, an AMPK inhibitor. Cytotoxicity and apoptosis induction were determined by MTT assay, trypan blue exclusion assay, annexin V-propidium iodide (PI) double staining assay, and cell cycle analysis. RESULTS: Morusin increased the formation of LC3 puncta in the cytoplasm and upregulated the expression of autophagy-related 5 (Atg5), Atg12, beclin-1, and LC3II in NSCLC cells, demonstrating that morusin could induce autophagy. Treatment with bafilomycin A1 markedly reduced cell viability but increased proportions of sub-G1 phase cells and annexin V-positive cells in H460 cells. These results indicate that morusin can trigger autophagy in NSCLC cells as a defense mechanism against morusin-induced apoptosis. Furthermore, we found that AMPK and its downstream acetyl-CoA carboxylase (ACC) were phosphorylated, while mammalian target of rapamycin (mTOR) and its downstream p70S6 kinase (p70S6K) were dephosphorylated by morusin. Morusin-induced apoptosis was significantly increased by treatment with compound C in H460 cells. These results suggest that morusin-induced AMPK activation could protect NSCLC cells from apoptosis probably by inducing autophagy. CONCLUSIONS: Our findings suggest that combination treatment with morusin and autophagy inhibitor or AMPK inhibitor might enhance the clinical efficacy of morusin for NSCLC.

Cytotoxicity Effects of Mouse IgG Produced against Three Nanoliposomal Human DR5 Receptor Epitopes on Breast Cancer Cells

  • Amirijavid, Shaghayegh;Entezari, Maliheh;Movafagh, Abolfazl;Hashemi, Mehrdad;Mosavi-Jarahi, Alireza;Dehghani, Hossein
    • Asian Pacific Journal of Cancer Prevention
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    • 제17권sup3호
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    • pp.257-261
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    • 2016
  • Cancer causes cells to avoid death while being the second cause of death in the world itself. Damaged cells in the absence of apoptosis will increasingly amplify their inefficient genome. Of the two main apoptosis inducing pathways in cells, the first has p53 protein as the main initiating factor in the cascade. According to research results this protein s mutated in 50% of cancers and sointerest has cooncentrated on the second pathway that features death receptors. Among these receptors TRAIL1/DR5 is especially expressed in cancer cells. So targeting such receptors can initiate the apoptotic cascade in cells. Interestingly by substitution of activating ligands with antibodies as agonists, we could efficiently turn on the apoptosis pathway. First of all, three small peptides from the DR5 protein extracellular domain were synthesized and injected with two different kind of adjuvants (Fround and liposomal encapsulation) separately into mice at 15 day intervals. As a result, liposomal peptides induced the immune system more efficient than Frounds adjuvant and at the end point the antibodies which were obtained from liposomal peptide injection induced much more effective death. Liposomal formol could be used as an adjuvant in immunization utilizing small peptides. They carry, protect and deliver peptides very efficiently. In addition, small peptides of a certain size from the extracellular domain of DR5 proteins not only can induce immune system but also produce antibodies playing a remarkable anti-cancer roles against breast cancer cells (MCF-7).

Isoflavone Content and its Relationship with Other Seed Quality Traits of Soybean Cultivars Collected in South Korea

  • Kim, Sun-Lim;Chi, Hee-Youn;Kim, Jung-Tae;Lee, Yeong-Ho;Park, Nam-Kyu;Son, Jong-Rok;Kim, Si-Ju
    • 한국작물학회지
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    • 제51권1호
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    • pp.81-88
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    • 2006
  • The 117 soybean cultivars were collected from nine provinces in Korea, and various seed quality traits along with isoflavone contents were evaluated to elucidate their relationship. The 100-seed weight of the black soybean (31.2 g) was significantly higher (p<0.05) than yellow soybeans (28.6 g). The composition of genistein, daidzein, and glycitein accounted for 75.8, 22.8, and 1.4 % of total isoflavone in yellow soybean cultivars, while their compositions in black soybeans were 58.5, 39.7, and 1.8%, respectively. The mean contents of total isoflavone in yellow and black soybean were $l,561.6{\mu}g\;g^{-1}\;and\;l,018.3{\mu}g\;g^{-1}$. The isofalvone content showed significant variation among cultivars when classified by the seed size. In the yellow soybeans, total isoflavone content was higher in small size soybean cultivars $(1,776.0{\mu}g\;g^{-1})$ and medium size soybean cultivars $(1,714.3{\mu}g\;g^{-1})$ compared to large size ones $(1,518.5{\mu}g\;g^{-1})$. Genistein content was proved as the major factor determining the relationship between isoflavone content and 100-seed weights (r =-0.206*). Daidzein and glycitein, however, showed no significant relationship with the 100-seed weights. Isoflavone content was not significantly correlated with color parameters L (lightness) and a (redness) values, but color parameter b (yellowness) was positively correlated with glycitein (r=0.264*) in the yellow soybeans, while its negative correlation between daidzein (r=-0.245*) and total isoflavone (r=-0.256*) were observed in black soybeans. However, these findings suggested that the seed color value may not serve as an effective parameter for estimating the isoflavone intensity of the soybeans. Variation of protein and lipid contents between yellow soybeans (n=58) and black soybeans (n=59) was relatively stable, however, protein and lipid contents have no significant relationship with isoflavone content.

Effects of Down-regulation of HDAC6 Expression on Proliferation, Cell Cycling and Migration of Esophageal Squamous Cell Carcinoma Cells and Related Molecular Mechanisms

  • Li, Ning;Tie, Xiao-Jing;Liu, Pei-Jie;Zhang, Yan;Ren, Hong-Zheng;Gao, Xin;Xu, Zhi-Qiao
    • Asian Pacific Journal of Cancer Prevention
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    • 제14권2호
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    • pp.685-689
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    • 2013
  • Objective: To study the effects of down-regulation of HDAC6 expression on proliferation, cell cycling and migration of esophageal squamous cell carcinoma (ESCC) cells and related molecular mechanisms. Methods: ESCC cell line EC9706 cells were randomly divided into untreated (with no transfection), control siRNA (transfected with control siRNA) and HDAC6 siRNA (transfected with HDAC6 small interfering RNA) groups. Effects of HDAC6 siRNA interference on expression of HDAC6 mRNA and protein in EC9706 cells were investigated by semi-quantitative RT-PCR, Western blotting and immunocytochemistry methods. Effects of down-regulation of HDAC6 expression on cell proliferation, cell cycle, and cell migration were studied using a CCK-8 kit, flow cytometry and Boyden chambers, respectively. Changes of mRNA and protein expression levels of cell cycle related factor (p21) and cell migration related factor (E-cadherin) were investigated by semi-quantitative RT-PCR and Western blotting methods. Results: After transfection of HDAC6 siRNA, the expression of HDAC6 mRNA and protein in EC9706 cells was significantly downregulated. In the HDAC6 siRNA group, cell proliferation was markedly inhibited, the percentage of cells in G0/G1 phase evidently increased and the percentage of cells in S phase decreased, and the number of migrating cells significantly and obviously decreased. The mRNA and protein expression levels of p21 and E-cadherin in the HDAC6 siRNA group were significantly higher than those in the untreated group and the control siRNA group, respectively. Conclusions: HDAC6 siRNA can effectively downregulate the expression of HDAC6 mRNA and protein in EC9706 cells. Down-regulation of HDAC6 expression can obviously inhibit cell proliferation, arrest cell cycling in the G0/G1 phase and reduce cell migration. The latter two functions may be closely related with the elevation of mRNA and protein expression of p21 and E-cadherin.