• 제목/요약/키워드: Silenced

검색결과 85건 처리시간 0.027초

Methylation Status and Immunohistochemistry of BRCA1 in Epithelial Ovarian Cancer

  • Pradjatmo, Heru;Dasuki, Djaswadi;Anwar, Mohammad;Mubarika, Sofia;Harijadi, Harijadi
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제15권21호
    • /
    • pp.9479-9485
    • /
    • 2014
  • Background: Cancer initiation and progression are controlled by genetic and epigenetic events. One epigenetic process which is widely known is DNA methylation, a cause of gene silencing. If a gene is silenced the protein which it encodes will not expressed. Objectives: 1. Identify the methylation status of BRCA1 in patients with epithelial ovarian cancer (EOC)and assess BRCA1 protein expression in tumor tissue. 2. Examine whether BRCA1 gene methylation and BRCA1 protein are associated with survival of epithelial ovarian cancer patients. Methods: The study design was a prospective-cohort study, conducted at Sardjito hospital, Yogyakarta, Indonesia. Results: A total of 69 cases were analyzed in this study. The data showed that the methylation status of BRCA1 in EOC was positive in 89.9%, with clear protein expression of BRCA1 in 31.9%. Methylation status and expression of BRCA1 were not prognosticators of EOC patients. Menarche, CA125 level, clinical stage and residual tumor were independent factors for prognosis.

Knockdown of SMYD3 by RNA interference inhibits cervical carcinoma cell growth and invasion in vitro

  • Wang, Shu-zhen;Luo, Xue-gang;Shen, Jing;Zou, Jia-ning;Lu, Yun-hua;Xi, Tao
    • BMB Reports
    • /
    • 제41권4호
    • /
    • pp.294-299
    • /
    • 2008
  • Elevated expression of SMYD3 is a frequent genetic abnormality in several malignancies. Few studies knocking down SMYD3 expression in cervical carcinoma cells have been performed to date. In this paper, we established an inducible short hairpin RNA expression system to examine its role in maintaining the malignant phenotype of HeLa cells. After being induced by doxycycline, SMYD3 mRNA and protein expression were both reduced, and significant reductions in cell proliferation, colony formation and migration/invasion activity were observed in the SMYD3-silenced HeLa cells. The percentage of cells in sub-G1 was elevated and DNA ladder formation could be detected, indicating potent induction of apoptosis by SMYD3 knockdown. These findings imply that SMYD3 plays crucial roles in HeLa cell proliferation and migration/invasion, and that it may be a useful therapeutic target in human cervical carcinomas.

Glioma-Associated Oncogene Homolog1 (Gli1)-Aquaporin1 pathway promotes glioma cell metastasis

  • Liao, Zheng-qiang;Ye, Ming;Yu, Pei-gen;Xiao, Chun;Lin, Feng-yun
    • BMB Reports
    • /
    • 제49권7호
    • /
    • pp.394-399
    • /
    • 2016
  • Glioma-Associated Oncogene Homolog1 (Gli1) is known to be activated in malignant glioma; however, its downstream pathway has not been fully explained. The aim of this study was to explore the role of Gli1-Aquaporin1 (AQP1) signal pathway in glioma cell survival. Our data suggests that both Gli1 and AQP1 are upregulated in glioma tissues, as in comparison to in normal tissues. These up-regulation phenomena were also observed in glioma U251 and U87 cells. It was demonstrated that Gli1 positively regulated the AQP1 expression. By luciferase reporter gene and ChIP assay, we observed that this modulation process was realized by combination of Gli1 with AQP1 promotor. In addition, knock down of Gli1 by siRNA interference reduced the viability of glioma cells as well as suppressed cell metastasis. Also, the inhibitory effects of cell survival by silenced Gli1 were abrogated by AQP1 overexpression. In summary, glioma cell survival is a regulatory process and can be mediated by Gli1-AQP1 pathway.

Involvement of NRF2 Signaling in Doxorubicin Resistance of Cancer Stem Cell-Enriched Colonospheres

  • Ryoo, In-geun;Kim, Geon;Choi, Bo-hyun;Lee, Sang-hwan;Kwak, Mi-Kyoung
    • Biomolecules & Therapeutics
    • /
    • 제24권5호
    • /
    • pp.482-488
    • /
    • 2016
  • Cancer stem cells (CSCs) are a subset of tumor cells, which are characterized by resistance against chemotherapy and environmental stress, and are known to cause tumor relapse after therapy. A number of molecular mechanisms underlie the chemoresistance of CSCs, including high expression levels of drug efflux transporters. We investigated the role of the antioxidant transcription factor NF-E2-related factor 2 (NRF2) in chemoresistance development, using a CSC-enriched colonosphere system. HCT116 colonospheres were more resistant to doxorubicin-induced cell death and expressed higher levels of drug efflux transporters such as P-glycoprotein (Pgp) and breast cancer resistance protein (BCRP) compared to HCT116 monolayers. Notably, levels of NRF2 and expression of its target genes were substantially elevated in colonospheres, and these increases were linked to doxorubicin resistance. When NRF2 expression was silenced in colonospheres, Pgp and BCRP expression was downregulated, and doxorubicin resistance was diminished. Collectively, these results indicate that NRF2 activation contributes to chemoresistance acquisition in CSC-enriched colonospheres through the upregulation of drug efflux transporters.

Sulforaphane Inhibits the Proliferation of the BIU87 Bladder Cancer Cell Line via IGFBP-3 Elevation

  • Dang, Ya-Mei;Huang, Gang;Chen, Yi-Rong;Dang, Zhong-Feng;Chen, Cheng;Liu, Feng-Lei;Guo, Ying-Fang;Xie, Xiao-Dong
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제15권4호
    • /
    • pp.1517-1520
    • /
    • 2014
  • Aim: To investigate effects of sulforaphane on the BIU87 cell line and underlying mechanisms involving IGFBP-3. Methods: Both BIU87 and IGFBP-3-silenced BIU87 cells were treated with sulforaphane. Cell proliferation was detected by MTT assay. Cell cycle and apoptosis were determined via flow cytometry. Quantitative polymerase chain reaction and Western blotting were applied to analyze the expression of IGFBP-3 and NF-${\kappa}B$ at both mRNA and protein levels. Results: Sulforaphane (80 ${\mu}M$) treatment could inhibit cell proliferation, inducing apoptosis and cell cycle arrest at G2/M phase. All these effects could be antagonized by IGFBP-3 silencing. Furthermore, sulforaphane (80 ${\mu}M$) could down-regulate NF-${\kappa}B$ expression while elevating that of IGFBP-3. Conclusions: Sulforaphane could suppress the proliferation of BIU87 cells via enhancing IGFBP-3 expression, which negatively regulating the NF-${\kappa}B$ signaling pathway.

Epigenetic Regulation of miR-129-2 Leads to Overexpression of PDGFRa and FoxP1 in Glioma Cells

  • Tian, Xiang-Yang;Zhang, Ling;Sun, Lai-Guang;Li, Ming
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제16권14호
    • /
    • pp.6129-6133
    • /
    • 2015
  • miR-129-2 is frequently downregulated in multiple cancers. However, how it is silenced in cancers remains unclear. Here we investigated the expression profile and potential biological function of miR-129-2 in glioblastoma (GBM), the most common and lethal form of brain tumors in adults. We showed that miR-129-2 is lost in GBM patient specimens and cultured cell lines. miR-129-2 expression could be restored upon treatment with a histone deadetylase inhibitor (trichostatin A) but not a DNA methylation inhibitor (5-Aza-2'-deoxycytidine), and more profound effect was observed with the treatment of these two drugs in combination. Furthermore, forced expression of miR-129-2 repressed the expression of major oncogenic genes such as PDGFRa and Foxp1 in GBMs. Consistently, expression of miR-129-2 significantly inhibits GBM cell proliferation in vitro. These results reveal that miR-129-2 is epigenetically regulated and functions as a tumor suppressor gene in GBMs, suggesting it may serve as a potential therapeutic target for GBM treatment.

Expression and Underlying Roles of IGFBP-3 in Paclitaxel-Treated Gastric Cancer Sgc-7901 Cells

  • Huang, Gang;Dang, Zhong-Feng;Dang, Ya-Mei;Cai, Wei;Li, Yuan;Chen, Yi-Rong;Xie, Xiao-Dong
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제15권14호
    • /
    • pp.5741-5745
    • /
    • 2014
  • Purpose: To study the expression of insulin-like growth factor binding proteins (IGFBPs) in paclitaxel-treated gastric cancer SGC-7901 cells, and to further investigate underlying mechanisms. Materials and Methods: Real time PCR and Western blot assays were applied to detect the mRNA and protein expression of IGFBP-2, -3 and -5 after paclitaxel (10 nM) treatment of SGC-7901 cells. In addition IGFBP-3 expression was silenced by RNA interference to determine effects. Cell viability was determined by MTT assay. Cell cycling and apoptosis were assessed by flow cytometry. Results: Compared to the control group, only IGFBP-3 expression was elevated significantly after paclitaxel (10 nM) treatment (p<0.05). Paclitaxel treatment caused cell cycle arrest and apoptosis via downregulating Bcl-2 expression. However, the effect could be abrogated by IGFBP-3 silencing. Conclusions: IGFBP-3 exhibits anti-apoptotic effects on paclitaxel-treated SGC-7901 cells via elevating Bcl-2 expression.

"Entanglement of Echoes in Near / Miss" Bernstein, Charles. Near / Miss Chicago: U of Chicago P, 2018.

  • Feng, Yi
    • 영어영문학
    • /
    • 제64권2호
    • /
    • pp.299-305
    • /
    • 2018
  • Near / Miss, Charles Bernstein's poetry collection, is replete with poems of distinctive styles and pluralistic forms in his idiosyncratic and artistic cosmos. With poetic antics, queerness, sarcasm, irony, and humor, the book showcases the motif of loss, chaos and trauma in postmodern America and the world. The multiplicity and multi-dimensional $M{\ddot{o}}bius$ effect in Near / Miss echo earlier Bernstein's poems, as well as poems by ancient and contemporary poets, with visual artists and musicians, and rabbis and Jewish philosophers. I argue that Near / Miss offers an apotheosis of echopoetics, which has been launched in his previous book Pitch of Poetry. Poems in the book reveal the dark and thick "pitch," namely the queer, the uncanny, the invisible, the disabled, the dispossessed, and the silenced poetic Other and make it explicit. The estrangement and alienation of $clich{\acute{e}}$ through diverse malaprops, mondegreens, non-sequiturs and fragmentations in Near / Miss aim at deconstructing the fixation of language so as to display the poetic Other. The motif of "nothingness" in echopoetics significantly multiplies its meanings. Nothingness mainly refers to the loss of origin, the defiance of tyranny, and the sublimity of the universe and the poetic Other. Melding his personal loss and misfortune, the current political discontent and the postmodern chaos in America and the world, nothingness in echopoetics resonates with American literary tradition and Zen with a healing and transforming power.

캄보디아 2017: 민주주의의 붕괴 (Cambodia in 2017: Democracy Collapsed)

  • 정연식
    • 동남아시아연구
    • /
    • 제28권1호
    • /
    • pp.121-144
    • /
    • 2018
  • 캄보디아의 2017년은 격동의 한 해였다. 6월에 치러진 지방선거는 처음으로 부정선거 시비가 사라진 모범적인 선거였다. 집권당인 캄보디아인민당은 과반의 지지를 획득했음에도 불구하고 선거결과에 만족하지 않고 정당법 개정을 통해 야당인 캄보디아구국당을 해산했다. 캄보디아구국당 대표는 반역 혐의로 구속되었고 정부에 비판적인 신문사와 방송국이 무더기로 폐쇄되었다. 표현의 자유를 박탈당한 시민사회는 고도의 감시와 사찰 속에 극도로 위축되었다. 캄보디아의 민주주의 붕괴에 대한 외부의 우려와 경고에 대해 캄보디아 정부는 중국의 지원을 등에 업고 정면으로 맞서고 있다. 정치적 격변 속에서도 캄보디아 경제는 꾸준히 고도의 성장률을 유지했지만 외형적 성장 이면의 구조적 취약점은 지속가능성을 위협하고 있다.

Human Endogenous Retroviruses as Gene Expression Regulators: Insights from Animal Models into Human Diseases

  • Durnaoglu, Serpen;Lee, Sun-Kyung;Ahnn, Joohong
    • Molecules and Cells
    • /
    • 제44권12호
    • /
    • pp.861-878
    • /
    • 2021
  • The human genome contains many retroviral elements called human endogenous retroviruses (HERVs), resulting from the integration of retroviruses throughout evolution. HERVs once were considered inactive junk because they are not replication-competent, primarily localized in the heterochromatin, and silenced by methylation. But HERVs are now clearly shown to actively regulate gene expression in various physiological and pathological conditions such as developmental processes, immune regulation, cancers, autoimmune diseases, and neurological disorders. Recent studies report that HERVs are activated in patients suffering from coronavirus disease 2019 (COVID-19), the current pandemic caused by SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) infection. In this review, we describe internal and external factors that influence HERV activities. We also present evidence showing the gene regulatory activity of HERV LTRs (long terminal repeats) in model organisms such as mice, rats, zebrafish, and invertebrate models of worms and flies. Finally, we discuss several molecular and cellular pathways involving various transcription factors and receptors, through which HERVs affect downstream cellular and physiological events such as epigenetic modifications, calcium influx, protein phosphorylation, and cytokine release. Understanding how HERVs participate in various physiological and pathological processes will help develop a strategy to generate effective therapeutic approaches targeting HERVs.