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Title: Transcriptional regulation of miR-146b by C/EBPβ LAP2 in esophageal cancer cells

Abstract

Highlights: • MiR-146b promotes esophageal cancer cell proliferation. • MiR-146b inhibits esophageal cancer cell apoptosis. • C/EBPβ directly binds to miR-146b promoter conserved region. • MiR-146b is up-regulated by C/EBPβ LAP2 transcriptional activation. - Abstract: Recent clinical study indicated that up-regulation of miR-146b was associated with poor overall survival of patients in esophageal squamous cell carcinoma. However, the underlying mechanism of miR-146b dysregulation remains to be explored. Here we report that miR-146b promotes cell proliferation and inhibits cell apoptosis in esophageal cancer cell lines. Mechanismly, two C/EBPβ binding motifs are located in the miR-146b promoter conserved region. Among the three isoforms of C/EBPβ, C/EBPβ LAP2 positively regulated miR-146b expression and increases miR-146b levels in a dose-dependent manner through transcription activation of miR-146b gene. Together, these results suggest a miR-146b regulatory mechanism involving C/EBPβ, which may contribute to the up-regulation of miR-146b in esophageal squamous cell carcinoma.

Authors:
 [1];  [2];  [3]; ;  [4];  [5];  [1]
  1. Department of Medical Genetics, Third Military Medical University, Chongqing (China)
  2. Department of Pathophysiology and High Altitude Physiology, Third Military Medical University, Chongqing (China)
  3. Department of Thoracic and Cardiac Surgery, Southwest Hospital, Third Military Medical University, Chongqing (China)
  4. Institute of Bioinformatics and Biosignal Transduction, College of Bioscience and Biotechnology, National Cheng Kung University, Tainan, Taiwan (China)
  5. Molecular Biology Center, State Key Laboratory of Trauma, Burn, and Combined Injury, Research Institute of Surgery and Daping Hospital, Third Military Medical University, Chongqing (China)
Publication Date:
OSTI Identifier:
22416343
Resource Type:
Journal Article
Resource Relation:
Journal Name: Biochemical and Biophysical Research Communications; Journal Volume: 446; Journal Issue: 1; Other Information: Copyright (c) 2014 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
60 APPLIED LIFE SCIENCES; APOPTOSIS; CARCINOMAS; CELL PROLIFERATION; DOSES; ESOPHAGUS; GENES; PATIENTS; PROMOTERS; TRANSCRIPTION

Citation Formats

Li, Junxia, Shan, Fabo, Xiong, Gang, Wang, Ju-Ming, Wang, Wen-Lin, Xu, Xueqing, E-mail: buyi.chu@gmail.com, and Bai, Yun, E-mail: baiyungene@gmail.com. Transcriptional regulation of miR-146b by C/EBPβ LAP2 in esophageal cancer cells. United States: N. p., 2014. Web. doi:10.1016/J.BBRC.2014.02.096.
Li, Junxia, Shan, Fabo, Xiong, Gang, Wang, Ju-Ming, Wang, Wen-Lin, Xu, Xueqing, E-mail: buyi.chu@gmail.com, & Bai, Yun, E-mail: baiyungene@gmail.com. Transcriptional regulation of miR-146b by C/EBPβ LAP2 in esophageal cancer cells. United States. doi:10.1016/J.BBRC.2014.02.096.
Li, Junxia, Shan, Fabo, Xiong, Gang, Wang, Ju-Ming, Wang, Wen-Lin, Xu, Xueqing, E-mail: buyi.chu@gmail.com, and Bai, Yun, E-mail: baiyungene@gmail.com. Fri . "Transcriptional regulation of miR-146b by C/EBPβ LAP2 in esophageal cancer cells". United States. doi:10.1016/J.BBRC.2014.02.096.
@article{osti_22416343,
title = {Transcriptional regulation of miR-146b by C/EBPβ LAP2 in esophageal cancer cells},
author = {Li, Junxia and Shan, Fabo and Xiong, Gang and Wang, Ju-Ming and Wang, Wen-Lin and Xu, Xueqing, E-mail: buyi.chu@gmail.com and Bai, Yun, E-mail: baiyungene@gmail.com},
abstractNote = {Highlights: • MiR-146b promotes esophageal cancer cell proliferation. • MiR-146b inhibits esophageal cancer cell apoptosis. • C/EBPβ directly binds to miR-146b promoter conserved region. • MiR-146b is up-regulated by C/EBPβ LAP2 transcriptional activation. - Abstract: Recent clinical study indicated that up-regulation of miR-146b was associated with poor overall survival of patients in esophageal squamous cell carcinoma. However, the underlying mechanism of miR-146b dysregulation remains to be explored. Here we report that miR-146b promotes cell proliferation and inhibits cell apoptosis in esophageal cancer cell lines. Mechanismly, two C/EBPβ binding motifs are located in the miR-146b promoter conserved region. Among the three isoforms of C/EBPβ, C/EBPβ LAP2 positively regulated miR-146b expression and increases miR-146b levels in a dose-dependent manner through transcription activation of miR-146b gene. Together, these results suggest a miR-146b regulatory mechanism involving C/EBPβ, which may contribute to the up-regulation of miR-146b in esophageal squamous cell carcinoma.},
doi = {10.1016/J.BBRC.2014.02.096},
journal = {Biochemical and Biophysical Research Communications},
number = 1,
volume = 446,
place = {United States},
year = {Fri Mar 28 00:00:00 EDT 2014},
month = {Fri Mar 28 00:00:00 EDT 2014}
}
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