PUBLICATION

Bromodomain and Extra-terminal Proteins (BET) Inhibitors Suppress Chondrocyte Differentiation and Restrain Bone Growth

Authors
Niu, N., Shao, R., Yan, G., Zou, W.
ID
ZDB-PUB-161110-19
Date
2016
Source
The Journal of biological chemistry   291(52): 26647-26657 (Journal)
Registered Authors
Niu, Ningning, Zou, Weiguo
Keywords
BET inhibitors, Col2a1, anticancer drug, bone, cartilage, chondrocyte, epigenetics
MeSH Terms
  • Animals
  • Bone Development/drug effects*
  • Cell Differentiation/drug effects*
  • Cell Proliferation/drug effects
  • Cells, Cultured
  • Chondrocytes/cytology
  • Chondrocytes/drug effects
  • Chondrocytes/metabolism
  • Chondrogenesis/drug effects*
  • Collagen Type II/metabolism
  • Gene Expression Regulation, Neoplastic/drug effects
  • Heterocyclic Compounds, 4 or More Rings/pharmacology
  • Humans
  • Mice
  • Multigene Family
  • Nuclear Proteins/antagonists & inhibitors*
  • Nuclear Proteins/genetics
  • Nuclear Proteins/metabolism
  • Promoter Regions, Genetic/genetics
  • Protein Serine-Threonine Kinases/antagonists & inhibitors*
  • Protein Serine-Threonine Kinases/genetics
  • Protein Serine-Threonine Kinases/metabolism
  • RNA-Binding Proteins/antagonists & inhibitors*
  • RNA-Binding Proteins/genetics
  • RNA-Binding Proteins/metabolism
  • Small Molecule Libraries/pharmacology
  • Transcription Factors/antagonists & inhibitors*
  • Transcription Factors/genetics
  • Transcription Factors/metabolism
  • Zebrafish/growth & development
  • Zebrafish/metabolism
PubMed
27821592 Full text @ J. Biol. Chem.
Abstract
Small-molecule inhibitors for bromodomain and extra-terminal proteins (BET) have recently emerged as potential therapeutic agents in clinical trials for various cancers. However, to date, it is unknown whether these inhibitors have side effects on bone structures. Here, we report that inhibition of BET bromodomain proteins may suppress chondrocyte differentiation and restrain bone growth. We generated a luciferase reporter system using the chondrogenic cell line, ATDC5, in which the luciferase gene was driven by the promoter of Col2a1, an elementary collagen of chondrocyte. The COL2A1-luc ATDC5 system was used for rapidly screening both activators and repressors of human collagen COL2A1 gene expression, and we found that BET bromodomain inhibitors reduce the COL2A1-luc. Consistent with the luciferase assay, BET inhibitors decrease the expression of Col2a1. Furthermore, we constructed a zebrafish line in which the Enhanced Green Fluorescent Protein (EGFP) expression was driven by Col2a1 promoter. The transgenic (Col2a1-EGFP) zebrafish line demonstrated that BET inhibitors I-BET151 and (+)-JQ1 may affect EGFP expression in zebrafish. Furthermore, we found that I-BET151 and (+)-JQ1 may affect chondrocyte differentiation in vitro and inhibit zebrafish growth in vivo. Mechanistic analysis revealed that BET inhibitors influenced the depletion of RNA polymerase II from the Col2a1 promoter. Collectively, these results suggest that BET bromodomain inhibition may have side effects on skeletal bone structures.
Genes / Markers
Figures
Show all Figures
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Antibodies
Orthology
Engineered Foreign Genes
Mapping