Parthenolide Sensitizes Human Colorectal Cancer Cells to Tumor Necrosis Factor-related Apoptosis-inducing Ligand through Mitochondrial and Caspase Dependent Pathway

( Kieu Thi Thu Trang ),( Se Lim Kim ),( Sang Bae Park ),( Seung Young Seo ),( Chung Hwan Choi ),( Jin Kyoung Park ),( Jin Chang Moon ),( Soo Teik Lee ),( Sang Wook Kim ) 대한장연구학회 2014 Intestinal Research Vol.12 No.1

Background/Aims: Combination therapy utilizing tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) in conjunction with other anticancer agents, is a promising strategy to overcome TRAIL resistance in malignant cells. Recently, parthenolide (PT) has proved to be a promising anticancer agent, and several studies have explored its use in combination therapy. Here, we investigated the molecular mechanisms by which PT sensitizes colorectal cancer (CRC) cells to TRAIL-induced apoptosis. Methods: HT-29 cells (TRAIL-resistant) were treated with PT and/or TRAIL for 24 hours. The inhibitory effect on proliferation was detected using the 3-(4, 5-dimethylthiazol-2yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. Annexin V staining, cell cycle analysis, and Hoechst 33258 staining were used to assess apoptotic cell death. Activation of an apoptotic pathway was confirmed by Western blot. Results: Treatment with TRAIL alone inhibited the proliferation of HCT 116 cells in a dose-dependent manner, whereas proliferation was not affected in HT-29 cells. Combination PT and TRAIL treatment significantly inhibited cell growth and induced apoptosis of HT-29 cells. We observed that the synergistic effect was associated with misregulation of B-cell lymphoma 2 (Bcl-2) family members, release of cytochrome C to the cytosol, activation of caspases, and increased levels of p53. Conclusion: Combination therapy using PT and TRAIL might offer an effetive strategy to overcome TRAIL resistance in certain CRC cells. (Intest Res 2014;12:34-41)

Antitumor effects of valdecoxib on hypopharyngeal squamous carcinoma cells

Trang Nguyen Thi Kieu,유훈 대한약리학회 2022 The Korean Journal of Physiology & Pharmacology Vol.26 No.6

The antitumoral effects of valdecoxib (Val), an United States Food and Drug Administration-approved anti-inflammatory drug that was withdrawn due to the side effects of increased risk of cardiovascular adverse events, were investigated in hypopharyngeal squamous cell carcinoma cells by performing a cell viability assay, transwell assay, immunofluorescence imaging, and Western blotting. Val markedly inhibited cell viability with an IC50 of 67.3 μM after 48 h of treatment, and also downregulated cell cycle proteins such as Cdks and their regulatory cyclin units. Cell migration and invasion were severely suppressed by inhibiting integrin α4/FAK expression. In addition, Val activated the cell cycle checkpoint CHK2 in response to excessive DNA damage, which led to the activation of caspase-3/9 and induced caspase-dependent apoptosis. Furthermore, the signaling cascades of the PI3K/AKT/ mTOR and mitogen-activated protein kinase pathways were significantly inhibited by Val treatment. Taken together, our results indicate that Val can be used for the treatment of hypopharyngeal squamous cell carcinoma.

Carbazole-Based Polyimide as a Hole-Transporting Material for Optoelectronic Applications

Thi Kieu Trang Tu,Sabrina Aufar Salma,정미진,김주현,정연태,제갈영순,임권택 한국고분자학회 2021 Macromolecular Research Vol.29 No.10

This paper reports the preparation of a novel polyimide (PI)-based holetransporting material comprising carbazole and arylamine moieties as the backbone of the polymer. A diamine monomer named 4,4'-(9H,9'H-[3,3'-bicarbazole]- 9,9'-diyl)dianiline is an electron-rich molecule which is suitable for achieving electrochromic materials. It is used to prepare an electrochromic carbazole-based PI via chemical imidization. The carbazole-based PI shows excellent thermal stability with a high decomposition temperature up to 500℃, refractive index of 1.74, and reasonable transparency of 85%. In addition, the PI exhibits characteristics similar to those of electrochromic materials such as violet-green emissions in the visible range when in solution form, highest occupied molecular orbital (HOMO) energy levels of ~5.4 eV, and a hole mobility of 7.44 × 10-4 cm2 V-1s-1. The excellent performance of the PI makes it a potential candidate for hole-transporting material in optoelectronic devices.

Tannic acid-induced apoptosis in FaDu hypopharyngeal squamous cell carcinoma

Loan Thi Ta,Trang Thi Kieu Nguyen,Hoon Yoo 대한구강생물학회 2019 International Journal of Oral Biology Vol.44 No.2

Tannic acid (TA) is a water-soluble polyphenol compound found in various herbal plants. We investigated the chemopreventive effects of TA on FaDu hypopharyngeal squamous carcinoma cells. In an 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, TA showed dose-dependent cytotoxicity with a half maximal inhibitory concentration (IC50) of 50 µM. Cell cycle analysis and immunofluorescence imaging demonstrated that under low-dose (25 µM) treatment, FaDu cells were arrested in G2/M phase, and as the dose of TA was increased, apoptosis was induced with the increase of cell population at sub-G1 phase. The expressions of various cyclins, including cyclin D1 and cyclin-dependent kinases (CDK-1 and CDK-2), were down-regulated at low doses of TA, whereas apoptotic effectors such as cleaved caspase 3, cleaved caspase 7, and poly (ADP-ribose) polymerase (PARP) were expressed in a dose-dependent manner in Western blotting. In addition, TA-induced apoptosis of FaDu cells might be mediated by the extracellular signal-regulated kinase (ERK)/mitogen-activated protein kinase pathway, with the upregulation of p-AKT/p-PKB (phosphorylated protein kinase B) and p-ERK. Overall, our data support the hypothesis that TA is a potential candidate agent for the treatment of hypopharyngeal cancer.

Approximate-SAD Circuit for Power-efficient H.264 Video Encoding under Maintaining Output Quality and Compression Efficiency

Le Dinh Trang Dang,Nguyen Thi My Kieu,Ik Joon Chang,Jinsang Kim 대한전자공학회 2016 Journal of semiconductor technology and science Vol.16 No.5

We develop a novel SAD circuit for power-efficient H.264 encoding, namely a-SAD. Here, some highest-order MSB’s are approximated to single MSB. Our theoretical estimations show that our proposed design simultaneously improves performance and power of SAD circuit, achieving good power efficiency. We decide that the optimal number of approximated MSB’s is four under 8-bit YUV-420 format, the largest number not to affect video quality and compression-rate in our video experiments. In logic simulations, our a-SAD circuit shows at least 9.3% smaller critical-path delay compared to existing SAD circuits. We compare power dissipation under iso-throughput scenario, where our a-SAD circuit obtains at least 11.6% power saving compared to other designs. We perform same simulations under two-and three-stage pipelined architecture. Here, our a-SAD circuit delivers significant performance (by 13%) and power (by 17% and 15.8% for two and three stages respectively) improvements.

A Study on Land Policy and Land Law in Vietnam after 1945

이성화,Trinh Thi Kieu Trang 한국국토정보공사 2017 지적과 국토정보 Vol.47 No.2

In every country, land has always been considered a particularly important resource and property. For Vietnam, a populous country with a relatively narrow cultivated land, the land is even more valuable because property is scarce in the process of building and developing the nation. Therefore, land administration is highly valued by the Vietnamese government and is a big priority. The study of land law and land policy in Vietnam from 1945 to present is a comprehensive view of the changes in land administration policy in Vietnam in each historical period. The study also provides the experiences and lessons learned in the field of land law and land administration in a country that has risen from the ashes of war, has accomplished reunification and has transformed from a centrally-planned economy, a feature of the communist economy, to a socialist-oriented market economy

The Novel Carbazole-based Polyimide as The Hole Transporting Material for Optoelectronic Application

이시윤,Tu Thi Kieu Trang,박찬,임권택 한국고분자학회 2020 한국고분자학회 학술대회 연구논문 초록집 Vol.45 No.2

High-refractive index of crosslinked polyimide for matching film in optoelectronic device

박한솔,( Tu Thi Kieu Trang ),이시윤,박찬,임권택 한국공업화학회 2020 한국공업화학회 연구논문 초록집 Vol.2020 No.-

A high-refractive index polymer of polyimide was prepared by imidization in removing water. Initially, the poly(amic acid) (PAA) was simply and quickly synthesized by the reaction between 4,4'-(hexa-fluoroisopropylidene) diphthalic anhydride (6FDA) and bis(3-aminophenyl) sulfone (3DDS). Next step, PAA was transformed to polyimide (PI). Finally, the polyimides were connected together to form network by cross-linking agent. This polymer network was characterized by FT-IR, GPC, TGA, transmittance and refractive index. With the high-refractive-index and thermal, flexible characteristic, this novel polyimide could be potential material to be utilizing as the outcoupling layer, the hole transport layer or the emitting layer in optoelectronic device applications.

Synergistic Effect of Parthenolide in Combination with 5-Fluorouracil in SW480 Cells

( Se Lim Kim ),( Thu Trang Thi Kieu ),( Byung Jun Jeon ),( Seong Hun Kim ),( In Hee Kim ),( Seung Ok Lee ),( Soo Teik Lee ),( Sang Wook Kim ) 대한장연구학회 2012 Intestinal Research Vol.10 No.4

Background/Aims: Parthenolide (PT) is responsible for the bioactivities of Feverfew. Besides its potent anti-inflammatory effect, this compound has recently been reported to induce apoptosis in cancer cells. Unfortunately, many of the therapies that use 5-fluorouracil (5-FU) alone or in combination with other agents are likely to become ineffective due to drug resistance. In the present study, we investigate the antitumor effect of PT combined with 5-FU on colorectal cancer cells. Methods: SW480 cell was employed as a representative of human colorectal carcinoma (CRC) cells. We performed MTT, annexin-V assay, and Hoechst 33258 staining to measure the synergistic effect. Western blotting was used to demonstrate apoptotic pathway. Results: Our result demonstrated that PT inhibited the viability of colorectal cancer cells and had synergistic anti-proliferation in combination with 5-FU. After combined treatment of 5-FU and PT, enhanced apoptotic cell death is observed using annexin-V FITC assay and it was revealed by the condensed chromatin and fragmented DNA. Compared with 5-FU or PT alone, the apoptosis of colorectal cancer cells treated with PT and 5-FU enhanced the activation of caspase-8, caspase-3. Conclusions: Combined treatment with PT may offer an efficacious strategy to overcome 5-FU resistance in certain CRC cells. (Intest Res 2012;10:357-364)

Risk of Material Misstatement in the Stage of Audit Planning: Empirical Evidence from Vietnamese Listed Enterprises

NGUYEN, Hoan,NGO, Thi Kieu Trang,LE, Thi Tam Korea Distribution Science Association 2020 The Journal of Asian Finance, Economics and Busine Vol.7 No.3

The purpose of this study is to investigate factors influencing risk assessment of material misstatement in Vietnamese enterprises listed on stock market. Expert interview method was conducted to discover the scales for three variables including information system, trademark, and risk assessment of material misstatement. Survey method was used to examine the impacts of eight factors on risk assessment of material misstatement. Data is collected from 317 auditors who have excellent experience in auditing financial statements of companies listed on stock market. Then, data is processed by descriptive statistics, reliability analysis, factor extracted analysis, correlative regression analysis, and analysis variance of residual change. The research findings showed that business characteristic, stakeholder pressure, and economic environment have positive relationships with risk assessment of material misstatement. Three variables including operation control and monitor, control environment, and information system negatively affect to risk assessment. Specially, business characteristic and information system, which are elements in internal control, have strongest impact on risk assessment. One the other hand, assessment of internal control plays an important role not only in the audit plan stage but also throughout the stages of the audit implementation and ending. Therefore, appropriate solutions are proposed to carry out all audit stages.