Down-Regulation of MicroRNA-210 Confers Sensitivity towards 1'S-1'-Acetoxychavicol Acetate (ACA) in Cervical Cancer Cells by Targeting SMAD4

Neoh Hun Phuah,Mohamad Nurul Azmi,Khalijah Awang,Noor Hasima Nagoor 한국분자세포생물학회 2017 Molecules and cells Vol.40 No.4

MicroRNAs (miRNAs) are short non-coding RNAs that regulate genes posttranscriptionally. Past studies have reported that miR-210 is up-regulated in many cancers including cervical cancer, and plays a pleiotropic role in carcinogenesis. However, its role in regulating response towards anti-cancer agents has not been fully elucidated. We have previously re-ported that the natural compound 1'S-1'-acetoxychavicol acetate (ACA) is able to induce cytotoxicity in various cancer cells including cervical cancer cells. Hence, this study aims to investigate the mechanistic role of miR-210 in regulating response towards ACA in cervical cancer cells. In the present study, we found that ACA down-regulated miR-210 expression in cervical cancer cells, and suppression of miR-210 expression enhanced sensitivity towards ACA by inhibiting cell proliferation and promoting apoptosis. Western blot analysis showed increased expression of mothers against decapentaplegic homolog 4 (SMAD4), which was predicted as a target of miR-210 by target prediction programs, following treatment with ACA. Luciferase reporter assay confirmed that miR-210 binds to sequences in 3UTR of SMAD4. Furthermore, decreased in SMAD4 protein expression was observed when miR-210 was overexpressed. Conversely, SMAD4 protein expression increased when miR-210 expression was suppressed. Lastly, we demonstrated that overexpression of SMAD4 augmented the anti-proliferative and apoptosis-inducing effects of ACA. Taken together, our results demonstrated that down-regulation of miR-210 conferred sensitivity towards ACA in cervical cancer cells by targeting SMAD4. These findings suggest that combination of miRNAs and natural compounds could provide new strategies in treating cervical cancer.

Down-Regulation of MicroRNA-210 Confers Sensitivity towards 1'S-1'-Acetoxychavicol Acetate (ACA) in Cervical Cancer Cells by Targeting SMAD4

Phuah, Neoh Hun,Azmi, Mohamad Nurul,Awang, Khalijah,Nagoor, Noor Hasima Korean Society for Molecular and Cellular Biology 2017 Molecules and cells Vol.40 No.4

MicroRNAs (miRNAs) are short non-coding RNAs that regulate genes posttranscriptionally. Past studies have reported that miR-210 is up-regulated in many cancers including cervical cancer, and plays a pleiotropic role in carcinogenesis. However, its role in regulating response towards anti-cancer agents has not been fully elucidated. We have previously reported that the natural compound 1'S-1'-acetoxychavicol acetate (ACA) is able to induce cytotoxicity in various cancer cells including cervical cancer cells. Hence, this study aims to investigate the mechanistic role of miR-210 in regulating response towards ACA in cervical cancer cells. In the present study, we found that ACA down-regulated miR-210 expression in cervical cancer cells, and suppression of miR-210 expression enhanced sensitivity towards ACA by inhibiting cell proliferation and promoting apoptosis. Western blot analysis showed increased expression of mothers against decapentaplegic homolog 4 (SMAD4), which was predicted as a target of miR-210 by target prediction programs, following treatment with ACA. Luciferase reporter assay confirmed that miR-210 binds to sequences in 3'UTR of SMAD4. Furthermore, decreased in SMAD4 protein expression was observed when miR-210 was overexpressed. Conversely, SMAD4 protein expression increased when miR-210 expression was suppressed. Lastly, we demonstrated that overexpression of SMAD4 augmented the anti-proliferative and apoptosis-inducing effects of ACA. Taken together, our results demonstrated that down-regulation of miR-210 conferred sensitivity towards ACA in cervical cancer cells by targeting SMAD4. These findings suggest that combination of miRNAs and natural compounds could provide new strategies in treating cervical cancer.

Centrifuge Tube Trap: A Direct-Sampling Mini Plankton Light Trap for Under 3USD

Seong Lee Neoh 한국해양과학기술원 2022 Ocean science journal Vol.57 No.1

Of the light plankton traps, tube traps are the simplest and easiest to construct. However, they have a serious limitation—the need to process the sample postharvest. This usually involves the time-consuming transfer of samples from the trap to a separate storage vessel. To eliminate this problem, a tube trap was constructed using a centrifuge tube that acts as both the trap and also the final storage vessel. The light source was an ordinary pen-style flashlight inserted in another centrifuge tube to waterproof it, which is then used to illuminate the sampling centrifuge tube. Post sampling, the centrifuge tube is capped and directly removed for storage with no concentration stage required. Field trials indicated that this centrifuge tube trap is effective in trapping phototactic organism, in particular the calanoid copepods.

Fabrication of lanthanum strontium cobalt ferrite (LSCF) cathodes for high performance solid oxide fuel cells using a low price commercial inkjet printer

Han, G.D.,Neoh, K.C.,Bae, K.,Choi, H.J.,Park, S.W.,Son, J.W.,Shim, J.H. Elsevier Sequoia 2016 Journal of Power Sources Vol.306 No.-

In this study, we investigate a method to fabricate high quality lanthanum strontium cobalt ferrite (LSCF) cathodes for solid oxide fuel cells (SOFCs) using a commercial low price inkjet printer. The ink source is synthesized by dissolving the LSCF nanopowder in a water-based solvent with a proper amount of surfactants. Microstructures of the LSCF layer, including porosity and thickness per printing scan cycle, are adjusted by grayscale in the printing image. It is successfully demonstrated that anode-supported SOFCs with optimally printed LSCF cathodes can produce decent power output, i.e., a maximum peak power density of 377 mW cm<SUP>-2</SUP> at 600 <SUP>o</SUP>C, in our experiment. We expect that this approach can support the quick and easy prototyping and evaluating of a variety of cathode materials in SOFC research.

Engineering LacI for Self-Assembly of Inorganic Nanoparticles on DNA Scaffold through the Understanding of LacI Binding to Solid Surfaces

Chen, Haibin,Su, Xiaodi,Neoh, Koon-Gee,Choe, Woo-Seok WILEY-VCH Verlag 2009 Advanced functional materials Vol.19 No.8

<P>The potential of utilizing the DNA binding protein lac repressor (Lacl) to organize inorganic nanoparticles (NPs) is explored in this study. A peptide cognitive of both SiO2 and TiO2 simultaneously (STB1, -CHKKPSKSC-) is genetically engineered into the C-terminus of Lacl-STB1, and the inserted STB1 peptides in the context of Lacl-STB1 molecules are shown to actively interact with both SiO2 and TiO2. Wild-type Lacl is found to interact with the two surfaces at its flexible N-terminal DNA binding domain, and Lacl-STB1 exhibits much stronger binding affinity to both surfaces by harnessing a second binding region (STB1 peptide) fused at its C-terminus. The quantitative analysis of binding kinetics reveals that, compared to wild-type Lacl with one binding region (N-terminus), two remote bindings regions (N-terminus and C-terminus) in Lacl-STB1 do not lead to faster adsorption rates to the two surfaces, but remarkably slow down the desorption rates. Finally, using Lacl-STB1 as a linker, the successful assembly of a sandwich nanostructure of DNA/Lacl-STB1/TiO2 NPs is demonstrated using surface plasmon resonance (SPR) measurements and TEM. The demonstrated Lacl-STB1-mediated assembly of TiO2 NPs on DNA scaffold may provide a generic platform for controlled spatial arrangement of various nanoparticles of engineering interest.</P>

Spatial Analysis of Colorectal Cancer Cases in Kuala Lumpur

Shah, Shamsul Azhar,Neoh, Hui-Min,Syed Abdul Rahim, Syed Sharizman,Azhar, Zahir Izuan,Hassan, Mohd Rohaizat,Safian, Nazarudin,Jamal, Rahman Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.3

Background: In Malaysia, data from the Malaysian Health Ministry showed colorectal cancer (CRC) to be the second most common type of cancer in 2007-2009, after breast cancer. The same was apparent after looking at males and females cases separately. In the present study, the Geographic Information System (GIS) was employed to describe the distribution of CRC cases in Kuala Lumpur (KL), Malaysia, according to socio-demographic factors (age, gender, ethnicity and district). Materials and Methods: This retrospective review concerned data for patients diagnosed with colorectal cancer in the years 1995 to 2011 collected from the Wilayah Persekutuan Health Office, taken from the cancer notification form (NCR-2), and patient medical records from the Surgical Department, Universiti Kebangsaan Malaysia Medical Centre (UKMMC). A total of 146 cases were analyzed. All the data collected were analysed using ArcGIS version 10.0 and SPSS version 19.0. Results: Patients aged 60 to 69 years accounted for the highest proportion of cases (34.2%) and males slightly predominated 76 (52.1%), Chinese had the highest number of registered cases at 108 (74.0%) and staging revealed most cases in the 3rd and 4th stages. Kernel density analysis showed more cases are concentrated up in the northern area of Petaling and Kuala Lumpur subdistricts. Spatial global pattern analysis by average nearest neighbour resulted in nearest neighbour ratio of 0.75, with Z-score of -5.59, p value of <0.01 and the z-score of -5.59. Spatial autocorrelation (Moran's I) showed clustering significant with p<0.01, Z score 3.14 and Moran's Index of 0.007. When mapping clusters with hotspot analysis (Getis-Ord Gi), hot and cold spots were identified. Hot spot areas fell on the northeast side of KL. Conclusions: This study demonstrated significant spatial patterns of cancer incidence in KL. Knowledge about these spatial patterns can provide useful information to policymakers in the planning of screening of CRC in the targeted population and improvement of healthcare facilities to provide better treatment for CRC patients.

Antibacterial activity of the thin ZnO film formed by atomic layer deposition under UV-A light

Park, Kang-Hee,Han, Gwon Deok,Neoh, Ke Chean,Kim, Taek-Seung,Shim, Joon Hyung,Park, Hee-Deung Elsevier 2017 CHEMICAL ENGINEERING JOURNAL -LAUSANNE- Vol.328 No.-

<P><B>Abstract</B></P> <P>For the application of ZnO nanoparticles to water disinfection, immobilization of the ZnO nanoparticles on reactor surfaces is required; otherwise, the nanoparticles aggregate and leave the reactor over time. To overcome these limitations, we formed thin ZnO films on a glass substrate using atomic layer deposition (ALD) (n=400 at 140°C). An X-ray diffraction pattern and scanning electron microscope (SEM) images demonstrated that the thin ZnO film consisted of closely packed nano-sized grains. The grains had hexagonal wurtzite crystalline structures, which were mostly oriented vertically from the substrate. The thin ZnO film did not show a change in the optical properties of ZnO: absorbance at <380nm and band gap of 3.25eV. Furthermore, the thin ZnO films produced reactive oxygen species (ROS) such as superoxide anion, hydroxyl radical, and singlet oxygen, by irradiation with UV-A light (350–400nm), and the production of ROS was not diminished even after repeated use. Antibacterial activity against <I>Staphylococcus aureus</I> was observed when the ZnO films were placed under UV-A light. However, this was not evident when the ZnO films were in the dark or when the glass substrate without the ZnO film was exposed to UV-A light, suggesting that the antibacterial activity was due to ROS production by the ZnO film under UV-A light. Moreover, the bacterial cells exposed to the ZnO film under UV-A light showed a crushed morphology, indicating that the ROS facilitated the disruption of the bacterial cell membranes. Taken together, this study demonstrates that ALD firmly anchored the ZnO nanocrystalline structures on the substrate without hampering the ROS production or antibacterial activity for the purpose of water disinfection.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A thin ZnO film was fabricated on a glass substrate using atomic layer deposition. </LI> <LI> The thin ZnO film consisted of vertically-grown closely-packed nano-sized grains. </LI> <LI> The thin ZnO film generated ROS under UV-A light like ZnO nanoparticles. </LI> <LI> Antibacterial mechanism was due to cellular membrane damage by produced ROS. </LI> <LI> The thin ZnO film has practical importance for water disinfection. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

High-Performance Silver Cathode Surface Treated with Scandia-Stabilized Zirconia Nanoparticles for Intermediate Temperature Solid Oxide Fuel Cells

Choi, Hyung Jong,Kim, Manjin,Neoh, Ke Chean,Jang, Dong Young,Kim, Hyun Joong,Shin, Jong Mok,Kim, Gyu-Tae,Shim, Joon Hyung Wiley (John WileySons) 2017 Advanced energy materials Vol.7 No.4

Slurry spin coating of thin film yttria stabilized zirconia/gadolinia doped ceria bi-layer electrolytes for solid oxide fuel cells

Kim, H.J.,Kim, M.,Neoh, K.C.,Han, G.D.,Bae, K.,Shin, J.M.,Kim, G.T.,Shim, J.H. Elsevier Sequoia 2016 Journal of power sources Vol. No.

Thin ceramic bi-layered membrane comprising yttria-stabilized zirconia (YSZ) and gadolinia-doped ceria (GDC) is fabricated by the cost-effective slurry spin coating technique, and it is evaluated as an electrolyte of solid oxide fuel cells (SOFCs). It is demonstrated that the slurry spin coating method is capable of fabricating porous ceramic films by adjusting the content of ethyl-cellulose binders in the source slurry. The porous GDC layer deposited by spin coating under an optimal condition functions satisfactorily as a cathode-electrolyte interlayer in the test SOFC stack. A 2-μm-thick electrolyte membrane of the spin-coated YSZ/GDC bi-layer is successfully deposited as a dense and stable film directly on a porous NiO-YSZ anode support without any interlayers, and the SOFC produces power output over 200 mW cm<SUP>-2</SUP> at 600 <SUP>o</SUP>C, with an open circuit voltage close to 1 V. Electrochemical impedance spectra analysis is conducted to evaluate the performance of the fuel cell components in relation with the microstructure of the spin-coated layers.

잉크젯 프린팅을 이용한 고체 산화물 연료전지 LSCF 양극 제작

한권덕(Gwon Deok Han),네오케체안(Ke Chean Neoh),배기호(Kiho Bae),최형종(Hyung Jong Choi),김현중(Hyun Joong Kim),손지원(Ji-Won Son),심준형(Joon Hyung Shim) 대한기계학회 2015 대한기계학회 춘추학술대회 Vol.2015 No.11