Krüppel-like factor 4 represses transcription of the survivin gene in esophageal cancer cell lines

2009 ◽  
Vol 390 (5/6) ◽  
Author(s):  
Guo Zhang ◽  
Hongxia Zhu ◽  
Yihua Wang ◽  
Shangbin Yang ◽  
Mei Liu ◽  
...  

Abstract Aberrant expression of survivin has been shown to be regulated at the transcription level in cancer cells. In this study, we demonstrate that there are six putative binding sites of Krüppel-like factor 4 (KLF4) within the 2000-bp region upstream of the transcription start site of the human survivin gene. Luciferase reporter gene assays revealed that survivin promoter activity is repressed upon overexpression of KLF4 in EC9706 cells. A chromatin immunoprecipitation assay indicated that KLF4 indeed binds the survivin promoter in vivo. It specifically binds the site located at position -40 among the six binding sites as determined by electrophoretic mobility shift assay. Ectopic expression of KLF4 decreases the mRNA and protein levels of survivin. Furthermore, overexpression of survivin partially reverses KLF4-induced cell apoptosis. These results indicate that KLF4 is a transcriptional repressor of the human survivin gene in esophageal squamous cancer cells.

2016 ◽  
Vol 2016 ◽  
pp. 1-14 ◽  
Author(s):  
Guoping Cao ◽  
Shenglan Gong ◽  
Fengxue Zhang ◽  
Wenjun Fu

Previous studies have revealed that uncontrollable stress can impair the synaptic plasticity and firing property of hippocampal neurons, which influenced various hippocampal-dependent tasks including memory, cognition, behavior, and mood. In this work, we had investigated the effects and mechanisms of the Chinese herbal medicine Xiao Yao San (XYS) against corticosterone-induced stress injury in primary hippocampal neurons (PHN) cells. We found that XYS and RU38486 could increase cell viabilities and decrease cell apoptosis by MTT, immunofluorescence, and flow cytometry assays. In addition, we observed that XYS notably inhibited the nuclear translocation of GR and upregulated the mRNA and protein expressions levels of Caveolin-1, GR, BDNF, TrkB, and FKBP4. However, XYS downregulated the FKBP51 expressions. Furthermore, the results of the electrophoretic mobility shift assay (EMSA) and double luciferase reporter gene detection indicated that FKBP4 promotes the transcriptional activity of GR reaction element (GRE) by binding with GR, and FKBP51 processed the opposite action. Thein vivoexperiment also proved the functions of XYS. These results suggested that XYS showed an efficient neuroprotection against corticosterone-induced stress injury in PHN cells by upregulating GRE transcriptional activity, which should be developed as a potential candidate for treating stress injury in the future.


2020 ◽  
Author(s):  
Wu Zhiyong ◽  
Luo Jie ◽  
Huang Tengyue ◽  
Yi Renhui ◽  
Ding Shengfeng ◽  
...  

Abstract Background: miRNAs have been reported to be involved in multiple biological processes of gliomas. Here, we aimed to analyze miR-4310 and its correlation genes involved in the tumor progression of human glioma.Methods: miR-4310 expression levels were examined in glioma and non-tumor brain (NB) tissues. The molecular mechanisms of miR-4310 expression and its effects on cell proliferation, migration, and invasion were explored by 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) , Transwell chamber, Boyden chamber, and western blot analyses, as well as in vivo tumorigenesis in nude mice. The relationships among miR-4310, SP1, and phosphatase and tensin homolog (PTEN) were explored by chromatin immunoprecipitation (ChIP), agarose gel electrophoresis, electrophoresis mobility shift (EMSA), and dual luciferase reporter gene assays. Results: miR-4310 expression was upregulated in glioma tissues compared to NB. Overexpressed miR-4310 promoted glioma cell proliferation, migration, and invasion in vitro and tumorigenesis in vivo . Inhibition of miR-4310 was sufficient to reverse these results. Mechanistic analyses revealed that miR-4310 promoted glioma progression through the PI3K/AKT pathway by targeting PTEN. Additionally, SP1 induced the expression of miR-4310 by binding to its promoter region. Conclusion: miR-4310 promotes the progression of glioma by targeting PTEN and activating the PI3K/AKT pathway meanwhile the expression of miR-4310 is induced by SP1.


2003 ◽  
Vol 31 (1) ◽  
pp. 105-121 ◽  
Author(s):  
A Nandy ◽  
S Jenatschke ◽  
B Hartung ◽  
K Milde-Langosch ◽  
AM Bamberger ◽  
...  

The NAD(+)-dependent 15-hydroxyprostaglandin dehydrogenase (PGDH) is a catabolic enzyme that controls the biological activities of prostaglandins by converting them into inactive keto-metabolites. Here we report the genomic organisation of the complete human PGDH gene and characterise its transcriptional regulation. The PGDH gene spans about 31 kb on chromosome 4 and contains 7 exons. Within 2.4 kb of the 5'-flanking sequence we identified two regions with clustered putative transcription factor binding sites. The distal promoter element PGDH-DE (positions-2152/-1944 relative to the start codon) contains binding sites for Ets and activating protein-1 (AP-1) flanked by two cAMP-responsive element-binding protein binding sites (CREB1, CREB2), whereas the proximal element PGDH-PE (-235/-153) includes an Ets and an AP-1 binding sequence. By electrophoretic mobility shift assay, no high affinity binding of Ets or AP-1 factors was observed with PGDH-PE, whereas we confirmed interaction of members of the Ets, AP-1 and CREB families of transcription factors with PGDH-DE. Transcriptional control of the PGDH promoter was assessed by transiently transfecting JEG-3 choriocarcinoma cells. A luciferase reporter gene construct containing the PGDH-PE was not induced by c-jun/c-fos in the absence or presence of co-expressed Ets-1. A construct carrying the PGDH-DE in front of the minimal homologous promoter was activated by co-transfection of expression vectors for AP-1 proteins. Mutation of the AP-1 or CREB2 site reduced the response to c-jun/c-fos, whereas mutation of the Ets site of the distal element reduced basal promoter activity. CREB activated the PGDH-DE construct through the CREB1 site. These results defined the distal element as an integrator of transcriptional regulation by AP-1, Ets and CREB proteins.


2020 ◽  
Author(s):  
Wu Zhiyong ◽  
Luo Jie ◽  
Huang Tengyue ◽  
Yi Renhui ◽  
Ding Shengfeng ◽  
...  

Abstract Background: miRNAs have been reported to be involved in multiple biological processes of gliomas. Here, we aimed to analyze miR-4310 and its correlation genes involved in the tumor progression of human glioma. Methods: miR-4310 expression levels were examined in glioma and non-tumor brain (NB) tissues. The molecular mechanisms of miR-4310 expression and its effects on cell proliferation, migration, and invasion were explored by 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) , Transwell chamber, Boyden chamber, and western blot analyses, as well as in vivo tumorigenesis in nude mice. The relationships among miR-4310, SP1, and phosphatase and tensin homolog (PTEN) were explored by chromatin immunoprecipitation (ChIP), agarose gel electrophoresis, electrophoresis mobility shift (EMSA), and dual luciferase reporter gene assays. Results: miR-4310 expression was upregulated in glioma tissues compared to NB. Overexpressed miR-4310 promoted glioma cell proliferation, migration, and invasion in vitro and tumorigenesis in vivo . Inhibition of miR-4310 was sufficient to reverse these results. Mechanistic analyses revealed that miR-4310 promoted glioma progression through the PI3K/AKT pathway by targeting PTEN. Additionally, SP1 induced the expression of miR-4310 by binding to its promoter region. Conclusion: miR-4310 promotes the progression of glioma by targeting PTEN and activating the PI3K/AKT pathway meanwhile the expression of miR-4310 is induced by SP1.


Author(s):  
Li-Ming Dong ◽  
Xi-Ling Zhang ◽  
Ming-Huan Mao ◽  
Yan-Pei Li ◽  
Xi-Yan Zhang ◽  
...  

Bladder cancer has easy recurrence characteristics, but its occurrence and development mechanism are still unclear. Non-coding RNA is a kind of RNA that exists widely and cannot be translated into proteins, which has played a key role in the regulation of biological functions of tumor cells. However, the regulation mechanism of non-coding RNA on bladder tumors is not fully understood. By microarray analysis and database analysis, we found that LINC00511 was significantly highly expressed in bladder cancer. The expressions of LINC00511, miR-143-3p, and PCMT in bladder cancer tissues and cells were detected by quantitative reverse transcription–polymerase chain reaction. The relationship between the expressions of miR-143-3p and PCMT1 and the clinicopathological parameters of the tumor was analyzed. The proliferation and invasion of bladder cancer cells were detected by MTT assay and Transwell assay. The expression levels of E-cadherin and vimentin in bladder cancer cells were detected by Western blot. Cell apoptosis was detected by flow cytometry. In vivo, TCCSUP or SW780 cells were inoculated into BALB/c nude mice to detect tumor volume and weight. Bioinformatics and dual luciferase reporter gene were used to analyze the relationship between LINC00511 and miR-143-3p and its downstream target gene PCMT1. The results showed that LINC00511 could target miR-143-3p/PCMT1 to regulate the proliferation, migration, and apoptosis of bladder cancer TCCSUP or SW780 cells and promote the occurrence and development of bladder cancer.


1995 ◽  
Vol 181 (1) ◽  
pp. 181-192 ◽  
Author(s):  
S Delphin ◽  
J Stavnezer

A large body of data indicate that antibody class switching is directed by cytokines by inducing or repressing transcription from unrearranged, or germline, CH genes. Interleukin 4 (IL-4) induces transcription of the germline C epsilon genes in activated B cells and subsequently, cells in this population will undergo switch recombination to immunoglobulin E. Furthermore, the data suggest that transcription of germline C epsilon genes is required for class switching. In this paper we define DNA elements required for induction of transcription of the germline C epsilon genes by IL-4. To do this, segments of DNA from the 5' flank of the initiation sites for germline epsilon RNA were ligated to a luciferase reporter gene and transfected into two mouse B cell lines, one of which can be induced to switch to IgE. By analysis of a series of 5' deletion constructs and linker-scanning mutations, we demonstrate that a 46-bp segment (residing at -126/-79 relative to the first RNA initiation site) contains an IL-4 responsive region. By electrophoretic mobility shift assays, we find that this segment binds three transcription factors: the recently described NF-IL4, one or more members of the C/EBP family of transcription factors, and NF-kappa B/p50. Mutation of any of the binding sites for these three factors abolishes or reduces IL-4 inducibility of the epsilon promoter. A 27-bp segment within this IL-4 response region containing binding sites for NF-IL4 and a C/EBP factor is sufficient to transfer IL-4 inducibility to a minimal c-fos promoter.


2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Yang Li ◽  
Hai Li ◽  
Xin Wei

Abstract Background Prostate cancer is one of the leading causes of cancer death in males. Recent studies have reported aberrant expression of lncRNAs in prostate cancer. This study explores the role of LINC00261 in prostate cancer progression. Methods The differentially expressed genes, transcription factors, and lncRNAs related to prostate cancer were predicted by bioinformatics analysis. Prostate cancer tissue samples and cell lines were collected for the determination of the expression of LINC00261 by reverse transcription quantitative polymerase chain reaction. The binding capacity of LINC00261 to the transcription factor GATA6 was detected by RIP, and GATA6 binding to the DKK3 promoter region was assessed by ChIP. In addition, luciferase reporter system was used to verify whether LINC00261 was present at the DKK3 promoter. After gain- and loss-of function approaches, the effect of LINC00261 on prostate cancer in vitro and in vivo was assessed by the determination of cell proliferation, invasion and migration as well as angiogenesis. Results LINC00261, GATA6, and DKK3 were poorly expressed in prostate cancer. LINC00261 could inhibit transcriptional expression of DKK3 by recruiting GATA6. Overexpression of LINC00261 inhibited prostate cancer cells proliferation, migration, and invasion as well as angiogenesis, which could be reversed by silencing DKK3. Furthermore, LINC00261 could also suppress the tumorigenicity of cancer cells in vivo. Conclusions Our study demonstrates the inhibitory role of LINC00261 in prostate cancer progression, providing a novel biomarker for early detection of prostate cancer.


2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Zhiyong Wu ◽  
Jie Luo ◽  
Tengyue Huang ◽  
Renhui Yi ◽  
Shengfeng Ding ◽  
...  

Abstract Background miRNAs have been reported to be involved in multiple biological processes of gliomas. Here, we aimed to analyze miR-4310 and its correlation genes involved in the progression of human glioma. Methods miR-4310 expression levels were examined in glioma and non-tumor brain (NB) tissues. The molecular mechanisms of miR-4310 expression and its effects on cell proliferation, migration, and invasion were explored using 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide, Transwell chamber, Boyden chamber, and western blot analyses, as well as its effect on tumorigenesis was explored in vivo in nude mice. The relationships between miR-4310, SP1, phosphatase, and tensin homolog (PTEN) were explored using chromatin immunoprecipitation, agarose gel electrophoresis, electrophoresis mobility shift, and dual-luciferase reporter gene assays. Results miR-4310 expression was upregulated in glioma tissues compared to that in NB tissues. Overexpressed miR-4310 promoted glioma cell proliferation, migration, and invasion in vitro, as well as tumorigenesis in vivo. The inhibition of miR-4310 expression was sufficient to reverse these results. Mechanistic analyses revealed that miR-4310 promoted glioma progression through the PI3K/AKT pathway by targeting PTEN. Additionally, SP1 induced the expression of miR-4310 by binding to its promoter region. Conclusion miR-4310 promotes the progression of glioma by targeting PTEN and activating the PI3K/AKT pathway; meanwhile, the expression of miR-4310 was induced by SP1.


2017 ◽  
Vol 2017 ◽  
pp. 1-12 ◽  
Author(s):  
Nan Wang ◽  
Yong Li ◽  
Jianhong Zhou

MicroRNA-31 (miR-31) functions as tumor suppressors or oncogenes that are involved in tumor behavior. However, the function of miR-31 in cervical carcinogenesis remains unclear. The aim of this study was to validate the potential role of miR-31 and BRCA1-associated protein-1 (BAP1) on regulating epithelial-mesenchymal transition (EMT) in cervical cancer. In the present study, qRT-PCR assay revealed that the expression of miR-31 was upregulated in human cervical cancer cells and clinical tissues. Results of wound healing and cell migration assay revealed that knockdown of miR-31 inhibited cell metastasis and migration. Bioinformatic and dual-luciferase reporter gene assay showed that BAP1 was the direct target of miR-31. Furthermore, the results revealed that miR-31 promoted proliferation and EMT in cervical cancer cells and accelerated the development of tumor growth in vivo xenograft experiment by inhibiting BAP1 expression. Overall, these results highlight an important role of miR-31 functioning as an oncomir which could promote EMT in cervical cancer via downregulating BAP1 expression. Thus, downregulation of miR-31 could be a novel approach for the molecular treatment of cervical cancers and other malignancies.


2020 ◽  
Author(s):  
Wu Zhiyong ◽  
Luo Jie ◽  
Huang Tengyue ◽  
Yi Renhui ◽  
Ding Shengfeng ◽  
...  

Abstract Background: miRNAs have been reported to be involved in multiple biological processes of gliomas. Here, we aimed to analyze miR-4310 and its correlation genes involved in the tumor progression of human glioma. Methods: miR-4310 expression levels were examined in glioma and non-tumor brain (NB) tissues. The molecular mechanisms of miR-4310 expression and its effects on cell proliferation, migration, and invasion were explored by 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) , Transwell chamber, Boyden chamber, and western blot analyses, as well as in vivo tumorigenesis in nude mice. The relationships among miR-4310, SP1, and phosphatase and tensin homolog (PTEN) were explored by chromatin immunoprecipitation (ChIP), agarose gel electrophoresis, electrophoresis mobility shift (EMSA), and dual luciferase reporter gene assays. Results: miR-4310 expression was upregulated in glioma tissues compared to NB. Overexpressed miR-4310 promoted glioma cell proliferation, migration, and invasion in vitro and tumorigenesis in vivo . Inhibition of miR-4310 was sufficient to reverse these results. Mechanistic analyses revealed that miR-4310 promoted glioma progression through the PI3K/AKT pathway by targeting PTEN. Additionally, SP1 induced the expression of miR-4310 by binding to its promoter region. Conclusion: miR-4310 promotes the progression of glioma by targeting PTEN and activating the PI3K/AKT pathway meanwhile the expression of miR-4310 is induced by SP1.


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