• Title/Summary/Keyword: Cell Polarity

Search Result 111, Processing Time 0.03 seconds

EXPRESSION OF E-CADHERIN WITH CORRELATION TO CLINICOPATHOLOGIC PARAMETERS IN ORAL SQUAMOUS CELL CARCINOMA (구강 편평세포암종에서 E-cadherin의 발현과 임상병리학적 지표와의 관계)

  • Shin, Jae-Myoung;Kim, Young-Sill;Kim, Chang-Hyen;Pyo, Sung-Woon
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
    • /
    • v.31 no.1
    • /
    • pp.1-6
    • /
    • 2005
  • It becomes more concerned that the cell adhesion molecule plays an important role in the process of malignant transformation and tumor behaviors including invasive growth and metastasis. It is postulated if the expression of adhesion molecule is reduced in tumor tissue, the tumor cell will be undifferentiated and lose their cell adhesion ability and polarity. So the tumor cells lost the adhesion of cell to cell and to basement membrane that they became more aggressive. Reduced cadherin expression enhances invasiveness through infiltrative growth and metastasis of tumor cells is well known and mostly accepted in many epithelia tumors. We explored the expression of E-cadherin by immunohistochemical staining in 50 oral squamous cell carcinomas and investigated the correlation between the expression of E-cadherin and clinicopathologic parameters and prognosis. The expression of E-cadherin was reduced in 40/50(80%) of primary tumors, and 21/22(95.5%) of lymph nodes. The reduced expression of the E-cadherin was associated with lymph node metastasis(P=0.029), invasive mode(P=0.030) and marginal status(P=0.038). Survival analysis showed that predictive period of E-cadherin reduced group(37 months) was lower than that of E-cadherin preserved group(60 months), but there was no statistical significant difference.

The I/LWEQ Domain in RapGAP3 Required for Posterior Localization in Migrating Cells

  • Lee, Mi-Rae;Kim, Hyeseon;Jeon, Taeck J.
    • Molecules and Cells
    • /
    • v.37 no.4
    • /
    • pp.307-313
    • /
    • 2014
  • Cell migration requires a defined cell polarity which is formed by diverse cytoskeletal components differentially localized to the poles of cells to extracellular signals. Rap-GAP3 transiently and rapidly translocates to the cell cortex in response to chemoattractant stimulation and localizes to the leading edge of migrating cells. Here, we examined localization of truncated RapGAP3 proteins and found that the I/LWEQ domain in the central region of RapGAP3 was sufficient for posterior localization in migrating cells, as opposed to leading-edge localization of full-length Rap-GAP3. All truncated proteins accumulated at the leading edge of migrating cells exhibited clear translocation to the cell cortex in response to stimulation, whereas proteins localized to the posterior in migrating cells displayed no translocation to the cortex. The I/LWEQ domain appears to passively accumulate at the posterior region in migrating cells due to exclusion from the extended front region in response to chemoattractant stimulation rather than actively being localized to the back of cells. Our results suggest that posterior localization of the I/LWEQ domain of RapGAP3 is likely related to F-actin, which has probably different properties compared to newly formed F-actin at the leading edge of migrating cells, at the lateral and posterior regions of the cell.

Cytotoxicity on Human Cancer Cells and Antitumorigenesis of Chungkookjang, a Fermented Soybean Product, in DMBA-Treated Rats (청국장의 암세포생장억제효과 및 흰쥐에서 DMBA 투여에 의한 유방종양발생 억제효과)

  • Kwak Chune-Shil;Kim Mee-Yeon;Kim Sung-Ae;Lee Mee-Sook
    • Journal of Nutrition and Health
    • /
    • v.39 no.4
    • /
    • pp.347-356
    • /
    • 2006
  • It is reported that a fermented soybean food, Doenjang, has srong antimutagenic and cytotoxic effect on cancer cells. This study investigated the effect of Chungkookjang, another traditional popular Korean soybean fermented food, on growth of cancer cells: HL-60, SNU-638 and MCF-7, and also its in vivo antitumorigenic effect in DMBA-induced mammary tumor rat model. For the in vitro study, Chungkookjang and steamed soybeans were extracted with ethanol and sequentially fractioned with 5 kinds of solvents differing in grades of polarity such as hexane, dichloromethane, ethylacetate, butanol and water. Almost all Chungkookjang extracts significantly inhibited the growth of HL-60 (human leukemic cancer cell), SNU-638 (human gastric cancer cell) and MCF-7 (human breast cancer cell) when compared to steamed soybean extracts. Butanol fraction of Chungkookjang extract especially showed a remarkable inhibitory effect in all the three kinds of cancer cells. To induce a mammary gland tumor, DMBA (50 mg/BW) was administered to 50 day-old female rats and followed by Chungkookjang or steamed soybean supplemented diets. Freezedried Chungkookjang powder (20% of diet in wet weight) was added to AIN-93G based diet for the Chungkookjang group of rats. Likewise, steamed soybean powder containing equal protein content to that of Chungkookjang powder was supplemented to soybean group of rats. At 13 weeks later, the mammary tumor incidence, average tumor number and tumor weight a rat were lower in Chungkookjang group compared to the control or soybean group. In conclusion, Chungkookjang showed a strong inhibitory effect on cancer cell growth in vitro, as well as a more preventive effect against chemically induced mammary tumorigenesis in vivo, while steamed soybeans did not. Therefore, these results suggest that Chungkookjang acquire its anticancer activity through the fermentation process.

Energy-band model on photoresponse transitions in biased asymmetric dot-in-double-quantum-well infrared detector

  • Sin, Hyeon-Uk;Choe, Jeong-U;Kim, Jun-O;Lee, Sang-Jun;No, Sam-Gyu;Lee, Gyu-Seok;Krishna, S.
    • Proceedings of the Korean Vacuum Society Conference
    • /
    • 2010.08a
    • /
    • pp.234-234
    • /
    • 2010
  • The PR transitions in asymmetric dot-in-double-quantum-well (DdWELL) photodetector is identified by bias-dependent spectral behaviors. Discrete n-i-n infrared photodetectors were fabricated on a 30-period asymmetric InAs-QD/[InGaAs/GaAs]/AlGaAs DdWELL wafer that was prepared by MBE technique. A 2.0-monolayer (ML) InAs QD ensemble was embedded in upper combined well of InGaAs/GaAs and each stack is separated by a 50-nm AlGaAs barrier. Each pixel has circular aperture of 300 um in diameter, and the mesa cell ($410{\times}410\;{\mu}m^2$) was defined by shallow etching. PR measurements were performed in the spectral range of $3{\sim}13\;{\mu}m$ (~ 100-400 meV) by using a Fourier-transform infrared (FTIR) spectrometer and a low-noise preamplifier. The asymmetric photodetector exhibits unique transition behaviors that near-/far-infrared (NIR/FIR) photoresponse (PR) bands are blue/red shifted by the electric field, contrasted to mid-infrared (MIR) with no dependence. In addition, the MIR-FIR dual-band spectra change into single-band feature by the polarity. A four-level energy band model is proposed for the transition scheme, and the field dependence of FIR bands numerically calculated by a simplified DdWELL structure is in good agreement with that of the PR spectra. The wavelength shift by the field strength and the spectral change by the polarity are discussed on the basis of four-level transition.

  • PDF

Upstream signalling of mTORC1 and its hyperactivation in type 2 diabetes (T2D)

  • Ali, Muhammad;Bukhari, Shazia Anwer;Ali, Muhammad;Lee, Han-Woong
    • BMB Reports
    • /
    • v.50 no.12
    • /
    • pp.601-609
    • /
    • 2017
  • Mammalian target of rapamycin complex 1 (mTORC1) plays a major role in cell growth, proliferation, polarity, differentiation, development, and controls transitioning between anabolic and catabolic states of the cell. It collects almost all extracellular and intracellular signals from growth factors, nutrients, and maintains cellular homeostasis, and is involved in several pathological conditions including, neurodegeneration, Type 2 diabetes (T2D), obesity, and cancer. In this review, we summarize current knowledge of upstream signaling of mTORC1 to explain etiology of T2D and hypertriglyceridemia, in which state, the role of telomere attrition is explained. We discuss if chronic inhibition of mTORC1 can reverse adverse effects resulting from hyperactivation. In conclusion, we suggest the regulatory roles of telomerase (TERT) and hexokinase II (HKII) on mTORC1 as possible remedies to treat hyperactivation. The former inhibits mTORC1 under nutrientrich while the latter under starved condition. We provide an idea of TOS (TOR signaling) motifs that can be used for regulation of mTORC1.

Structure Determination of Syndecan-4 Transmembrane Domain using PISA Wheel Pattern and Molecular Dynamics simulation

  • Choi, Sung-Sub;Jeong, Ji-Ho;Kim, Ji-Sun;Kim, Yongae
    • Journal of the Korean Magnetic Resonance Society
    • /
    • v.18 no.2
    • /
    • pp.58-62
    • /
    • 2014
  • Human transmembrane proteins (hTMPs) are closely related to transport, channel formation, signaling, cell to cell interaction, so they are the crucial target of modern medicinal drugs. In order to study the structure and function of these hTMPs, it is important to prepare reasonable amounts of proteins. However, their preparation is seriously difficult and time-consuming due to insufficient yields and low solubility of hTMPs. We tried to produce large amounts of Syndecan-4 transmembrane domain (Syd4-TM) that is related to the healing wounds and tumor for a long time. In this study, we performed the structure determination of Syd4-TM combining the Polarity Index at Slanted Angle (PISA) wheel pattern analysis based on $^{15}N-^1H$ 2D SAMPI-4 solid-state NMR of expressed Syd4-TM and Molecular Dynamics (MD) simulation using Discovery Studio 3.1.

Structural Change in Transmembrane Region of Syndecan-4 by Mutation

  • Choi, Sung-Sub;Kim, Ji-Sun;Jeong, Ji-Ho;Kim, Yongae
    • Journal of the Korean Magnetic Resonance Society
    • /
    • v.20 no.4
    • /
    • pp.129-137
    • /
    • 2016
  • Transmembrane(TM) proteins are closely related to transport, channel formation, signaling, cell to cell interaction, so they are the crucial target of modern medicinal drugs. In order to study the structure and function of these TM proteins, it is important to prepare reasonable amounts of proteins. However, their preparation is seriously difficult and time-consuming due to insufficient yields and low solubility of TM proteins. We tried to produce large amounts of Syndecan-4 containing TM domain(SDC4-TM) that is related to the wound healing and tumor. Also, mutated SDC4-TM was studied to investigate structural change by modification of dimerization motif. We performed the structure determination by the Polarity Index at Slanted Angle (PISA) wheel pattern analysis based on $^{15}N-^1H$ 2D SAMPI-4 solid-state NMR of SDC4-TM and computational modeling using Discovery Studio 2016.

Antiinflammatory and antioxidative effects of Agrimonia pilosa Ledeb

  • Sim, SY;Kim, GJ;Ko, SG
    • Advances in Traditional Medicine
    • /
    • v.7 no.3
    • /
    • pp.217-228
    • /
    • 2007
  • Agrimonia pilosa Ledeb. has long been used for a useful natural agent ameliorating inflammation related symptoms in the folk medicine recipe. This study was performed to investigate effects of Agrimonia pilosa Ledeb.(AP) on the expression of inflammation related genes such as the inducible nitric oxide synthase (iNOS) in macrophage cell line, RAW 264.7 cells. The AP (whole plants) was extracted with 80% ethanol and sequentially partitioned with solvents in order to increase polarity. Among the various solvent extracts of AP, the n-butanol (BuOH) fraction showed the most powerful inhibitory ability against nitric oxide (NO) production in lipopolysaccharide (LPS)-induced RAW 264.7 cells without affecting cell viability. Reverse transcriptase-polymerase chain reaction and Western blot analysis revealed that the BuOH fraction provided a primary inhibitor of the iNOS protein and mRNA expression in LPS-induced RAW 264.7 cells. The DPPH and OH radical scavenging activities of the several fractions of 80% ethanol extracts of AP significantly increased by EtOAC and BuOH fractions. Thus, the present study suggests that the response of a component of the BuOH fraction to NO generation via iNOS expression provide an important clue to elucidate anti-inflammatory mechanism of AP.

Erratum to: Upstream signalling of mTORC1 and its hyperactivation in type 2 diabetes (T2D)

  • Ali, Muhammad;Bukhari, Shazia Anwer;Ali, Muhammad;Lee, Han-Woong
    • BMB Reports
    • /
    • v.51 no.1
    • /
    • pp.45-53
    • /
    • 2018
  • Mammalian target of rapamycin complex 1 (mTORC1) plays a major role in cell growth, proliferation, polarity, differentiation, development, and controls transitioning between anabolic and catabolic states of the cell. It collects almost all extracellular and intracellular signals from growth factors, nutrients, and maintains cellular homeostasis, and is involved in several pathological conditions including, neurodegeneration, Type 2 diabetes (T2D), obesity, and cancer. In this review, we summarize current knowledge of upstream signaling of mTORC1 to explain etiology of T2D and hypertriglyceridemia, in which state, the role of telomere attrition is explained. We discuss if chronic inhibition of mTORC1 can reverse adverse effects resulting from hyperactivation. In conclusion, we suggest the regulatory roles of telomerase (TERT) and hexokinase II (HKII) on mTORC1 as possible remedies to treat hyperactivation. The former inhibits mTORC1 under nutrient-rich while the latter under starved condition. We provide an idea of TOS (TOR signaling) motifs that can be used for regulation of mTORC1.

Cyclopamine, an Antagonist of Hedgehog (Hh) Signaling Pathway, Reduces the Hatching Rate of Parthenogenetic Murine Embryos

  • Park, Jaehyun;Moon, Jeonghyeon;Min, Sol;Chae, Stephan;Roh, Sangho
    • Journal of Embryo Transfer
    • /
    • v.33 no.4
    • /
    • pp.237-243
    • /
    • 2018
  • Hedgehog (Hh) pathway plays a key role in development from invertebrate to vertebrate. It is known to be involved in cell differentiation, polarity, proliferation, including the development of vertebrate limb and the establishment of flies' body plan. To investigate how the regulation of Hh pathway affects the development of parthenogenetic murine embryos, the parthenogenetically activated murine embryos were treated with either cyclopamine (Cyc), an antagonist of Hh pathway, or purmorphamine, an agonist of Hh pathway. While Cyc did not affect the blastocyst formation and its total cell number, the chemical reduced the hatching rate of embryos and the expression levels of Fn1 mRNA. The results of the present study show the possibility that Cyc may affect the development of embryos at blastocyst stage by blocking Hh pathway and this may cause detrimental effect to the embryos at peri-, and post-implantation stages.