Transcriptional suppression of androgen receptor by 18β-glycyrrhetinic acid in LNCaP human prostate cancer cells

You Sun,Mingyue Jiang,Pil‑Hoon Park,Kyung Song 대한약학회 2020 Archives of Pharmacal Research Vol.43 No.4

Androgen receptor (AR) plays a pivotal role as atarget for amplification/mutation in pathogenesis and tumorprogression in prostate, and thus, controlling AR activityor expression might be a feasible therapeutic approach forthe treatment of prostate cancer. Here, we report the novelmechanisms by which 18β-glycyrrhetinic acid (GA) targetsAR to stimulate cell death in both hormone-responsive and-refractory prostate cancer cells. We found that miR-488, atumor suppressive microRNA, was markedly induced by GAtreatment, resulting in the down-regulation of AR expressionand inhibition of cellular responses mediated by androgens. Moreover, GA not only suppressed the expression of androgentarget genes (TMPRSS2, PSA, and NKX3.1), but alsoenhanced the suppressive effect of anti-androgens (bicalutamideand flutamide) on LNCaP cell growth. Our data furtherprovides evidence that down-regulation of AR expression byGA may occur through transcriptional suppression at AR promoter region between − 1014 and − 829. Ectopic expressionof SFR and E2F3α reversed the inhibitory effect of GAon AR promoter activity as well as protein expression, suggestingthat GA may target transcription factors SRF andE2F3α to regulate AR expression. Taken together, our studyprovides new insights on AR regulation and GA as a potentialtherapeutic candidate for human prostate cancer.

AR-mTOR-SRF Axis Regulates HMMR Expression in Human Prostate Cancer Cells

( You Sun ),( Zewu Li ),( Kyung Song ) 한국응용약물학회 2021 Biomolecules & Therapeutics(구 응용약물학회지) Vol.29 No.6

The elevated expression of the hyaluronan-mediated motility receptor (HMMR) is known to be highly associated with tumor progression in prostate cancer, but the molecular mechanisms underlying the regulation of HMMR expression remain unclear. Here, we report that mammalian target of rapamycin (mTOR) is a key regulator of HMMR expression, for which its kinase activity is required. Pharmacological inhibitors of mTOR, such as rapamycin and Torin2, markedly suppressed the mRNA level as well as the protein level of HMMR in LNCaP and PC-3 cells. Our data demonstrate that such regulation occurs at the transcription level. HMMR promoter reporter assays revealed that the transcription factor SRF is responsible for the mTOR-mediated transcriptional regulation of HMMR gene. Consistently, the suppression of HMMR expression by Torin2 was noticeably reversed by the overexpression of SRF. Moreover, our findings suggest that the SRF binding sites responsible for the transcriptional regulation of HMMR through the mTOR-SRF axis are located in HMMR promoter sequences carrying the first intron, downstream of the translational start site. Furthermore, the upregulation of HMMR by DHT was abolished by stimulation with rapamycin, prior to DHT treatment, suggesting that mTOR activity is required for the induction of HMMR expression by androgen. Collectively, our study provides new mechanistic insights into the role of mTOR/SRF/AR signaling in HMMR regulation in prostate cancer cells.

대학생의 그릿과 도움요청의 관계에서 성취목표의 매개효과

김유선 ( Kim¸ You-sun ),한천우 ( Han¸ Cheon-woo ) 한국아동교육학회 2021 아동교육 Vol.30 No.3

본 연구는 대학생을 대상으로 그릿과 성취목표, 도움요청행동 간의 구조적 관계를 살펴보고 성취 목표의 매개 효과에 대해 검증하고자 실시한 연구이다. 이를 위해 D광역시 소재 K대학 4년제 대학생 269명을 대상으로 설문 조사를 실시하였으며, 이 중 유효한 251명의 설문 자료를 최종분석에 사용하였다. 수집된 자료는 SPSS 25와 Mplus 8을 이용하여 구조방정식모형을 분석하였다. 본 연구의 주요 결과는 다음과 같다. 첫째, 그릿과 성취목표, 도움요청행동 간의 구조적 관계를 분석한 결과, 그릿은 도움회피만을 부적으로 예측하였다. 둘째, 성취목표 중 숙달목표는 대학생의 도움요청 행동에 직접적으로 유의미한 영향을 주었으며, 이 중 도구적 도움만을 긍정적으로 예측하였다. 셋째, 숙달목표만이 그릿과 도움요청행동 간의 관계에서 완전매개 또는 부분매개 역할을 하였다. 본 연구는 기존의 선행연구에서 다루지 않은 그릿과 도움요청행동 간의 관계를 살펴보고 대학생의 도움요청행동을 끌어낼 수 있는 변인으로 그릿의 역할과 숙달목표의 중요성을 시사해 주는 데에 의의를 가진다. This research was designed to investigate structural relationships among grit, achievement goals, help-seeking behaviors for university students. To do so, 269 university students in D city were participated for this study, but 19 of them were excluded for the final analyses. SPSS 25 and Mplus 8 were used to perform preliminary analyses and structural equation modeling. Major findings as follows. First of all, grit was positively associated with avoidant help-seeking behaviors. Second, direct effects of the mastery goals on college students’ help-seeking behaviors were significant. Specifically, the association with instrumental help-seeking was only positive. Third, mastery goals could partially or fully mediate between grit and help-seeking behaviors. This research has explored the relationships between grit and help-seeking behaviors which has not been directly tested, and theoretical and practical implication were suggested.

Fast distortion measurement method for MPEG point cloud compression

Yousun Park(박유선),Euee S. Jang(장의선) 대한전자공학회 2018 대한전자공학회 학술대회 Vol.2018 No.11

In this paper, we propose fast distortion quality measurement to improve efficient compression of massive point cloud data by introducing distortion search metric. In MPEG, point cloud compression standard is being actively standardized. As a new medium, point clouds pose new challenges in compression. One of them is to accurately assess the distortion of the encoded point clouds. If a point cloud is compressed lossy, there is no guarantee in mapping exact points between the original and encoded point clouds. For this reason, a tool called PC_ERROR [1] has been adopted for PCC. The PC_ERROR tool nicely solves the distortion measurement in an accurate manner; yet, it suffers from substantial computational complexity. To deal with this problem, we propose a fast distortion computing method to measure the Point Cloud Compression sequences. On top of PC_ERROR we designed new searching algorithm. Throughout the experimental results, we showed that the proposed method outperforms the PC_ERROR tool by 75 percent in execution time while preserving the accuracy in distortion measure.

Investigating variability in rater groups on L2 writing in English

Yousun Shin 한국언어과학회 2011 한국언어과학회 학술대회 Vol.2011 No.08

The purpose of the study is to investigate how the judgment of raters is biased toward certain rating criteria or task types in assessing Korean university students’ L2 writing. In addition, the study aims to examine whether or not non-native rater group and native rater group share the same judgment of students’ written products. Six raters scored 258 compositions written by Korean university students on two topics. The written products were rated using an analytic scoring scale with content, organization, language in use, grammar, and mechanics. For the first part, the FACETS analysis revealed that all six raters showed self-consistent scoring patterns across the rating categories in the two tasks. However, each rater was biased towards certain type of tasks and rating categories. For the second part of the study, the results of ANOVA and MANOVA tests revealed that there were significant mean differences between the two groups across the rating categories in both tasks except content in Task 2. It is also shown that the non-native rater group is harsher in their rating than the native rater group regardless of the rating category.

Development of a self-supervised machine learning algorithm for automatic MRI sequence-type classification

Yousun Ko,Seongwon Na,Youngbin Shin,Kyung Won Kim 한국실험동물학회 2023 한국실험동물학회 학술발표대회 논문집 Vol.2023 No.2

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Yousun Park(박유선) 한국디자인학회 2021 한국디자인학회 국제초대전도록 Vol.2021 No.5

The Effects of Graphic Organizers in L2 Writing Instruction

Yousun Shin 팬코리아영어교육학회(구 영남영어교육학회) 2009 영어교육연구 Vol.21 No.1

This article describes a case study that investigated the effects of using graphic organizers to enhance L2 writing ability. The results of the interview with an L2 writing instructor were used as the main sources for data analysis in the study. During the interview, the instructor was asked 12 questions which were categorized into three sections: the instructor's own definition of graphic organizers, instructional practices and applications of graphic organizers in writing instruction, and the instructor's perceptions on the effects of using graphic organizer as a writing strategy. The interview data demonstrated that graphic organizers can be a potential vehicle for L2 learners to enhance writing ability but proper instruction should carefully link to learners' proficiency level. Furthermore, learners also need to be cognizant of the purpose of a writing task, the requirements inherent in the task, and the criteria by which their written products are evaluated while employing a variety of graphic organizers. It is suggested that learners need to have an opportunity to use graphic organizers as a strategy to stimulate L2 writing which may contribute to cultivating learners' thinking and generating ideas for a given task.

Self Lubricator 2021

Yousun Park(박유선) 한국디자인학회 2021 한국디자인학회 국제초대전도록 Vol.2021 No.11

L2 Writing and Vocabulary Development : A Comparison of Lexical Quality Across Written Compositions with Different Planning Activities

Yousun Shin 한국중앙영어영문학회 2010 영어영문학연구 Vol.52 No.1

The purpose of the study is mainly to examine whether learners are able to improve their level of vocabulary through different types of planning activities. In addition, the study also aims at exploring the extent to which their vocabulary is improved and what difference is made with regard to the planning activities, which they utilized during their writing tasks. To see if planning activities was useful in improving the lexical quality of writing, three sets of timed compositions produced by 71 university students were analyzed using the Lexical Frequency Profile (LFP). The results indicated that there were significant differences among written compositions in terms of the three variables—word token, lexical variation, and lexical density. Overall, word token at most of the vocabulary levels tended to increase regardless of any type of planning activities while learners showed vocabulary improvement in terms of lexical variation including 1000 and ‘not in the list’ level. However, the result of lexical density showed that the planning activities did not affect the lexical density of the composition since learners got the highest scores in the first writing task with no planning activity. The implications of these findings are discussed with the usefulness of planning activities which help learners to effectively retrieve vocabulary and select correct forms.