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Title: Analysis of gene-expression profiles after gamma irradiation of normal human fibroblasts

Abstract

Purpose: To understand comprehensive transcriptional profile of normal human fibroblast in response to irradiation. Methods and Materials: To identify genes whose expression is influenced by {gamma} radiation, we used a cDNA microarray to analyze expression of 23,000 genes in normal human fibroblasts at 7 timepoints (1, 3, 6, 12, 24, 48, and 72 hours) after 5 different doses (0.5, 2, 5, 15, and 50 Gy) of exposure. Results: Among the genes that showed altered expression patterns, some were already known to be regulated by irradiation, for instance ODC, EGR1, FGF2, PCNA, PKC, and several p53-target genes, including p53DINP1, BTG2, GADD45, and MDM2. The time course of each dose showed that from 350 to 600 genes were affected as to their expression; induction profiles characteristic to each dose were demonstrated. Of the total identified, only 89 genes were up-regulated; the vast majority was down-regulated over the 72-hour time course. We identified 21 genes that were distinctly induced by irradiation; 11 of them were functionally known, and 6 of those were p53-target genes. Conclusions: The results underscored the complexity of the transcriptional responses to irradiation, and the data should serve as a basis for global characterization of radiation-regulated genes and pathways.

Authors:
 [1];  [2];  [3];  [4];  [4];  [2]
  1. Laboratory of Molecular Medicine, Human Genome Center, Institute of Medical Science, University of Tokyo, Tokyo (Japan) and Department of Radiation Oncology and Image-applied Therapy, Graduate School of Medicine, Kyoto University, Sakyo, Kyoto (Japan). E-mail: tachiiri@kuhp.kyoto-u.ac.jp
  2. Laboratory of Molecular Medicine, Human Genome Center, Institute of Medical Science, University of Tokyo, Tokyo (Japan)
  3. Laboratory for Medical Informatics, SNP Research Center, Riken - Institute of Physical and Chemical Research, Yokohama Institute, Tsurumi (Japan)
  4. Department of Radiation Oncology and Image-applied Therapy, Graduate School of Medicine, Kyoto University, Sakyo, Kyoto (Japan)
Publication Date:
OSTI Identifier:
20788295
Resource Type:
Journal Article
Resource Relation:
Journal Name: International Journal of Radiation Oncology, Biology and Physics; Journal Volume: 64; Journal Issue: 1; Other Information: DOI: 10.1016/j.ijrobp.2005.08.030; PII: S0360-3016(05)02395-3; Copyright (c) 2006 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:
62 RADIOLOGY AND NUCLEAR MEDICINE; FIBROBLASTS; GAMMA RADIATION; GENES; IRRADIATION; RADIATION DOSES

Citation Formats

Tachiiri, Seiji, Katagiri, Toyomasa, Tsunoda, Tatsuhiko, Oya, Natsuo, Hiraoka, Masahiro, and Nakamura, Yusuke. Analysis of gene-expression profiles after gamma irradiation of normal human fibroblasts. United States: N. p., 2006. Web. doi:10.1016/J.IJROBP.2005.0.
Tachiiri, Seiji, Katagiri, Toyomasa, Tsunoda, Tatsuhiko, Oya, Natsuo, Hiraoka, Masahiro, & Nakamura, Yusuke. Analysis of gene-expression profiles after gamma irradiation of normal human fibroblasts. United States. doi:10.1016/J.IJROBP.2005.0.
Tachiiri, Seiji, Katagiri, Toyomasa, Tsunoda, Tatsuhiko, Oya, Natsuo, Hiraoka, Masahiro, and Nakamura, Yusuke. Sun . "Analysis of gene-expression profiles after gamma irradiation of normal human fibroblasts". United States. doi:10.1016/J.IJROBP.2005.0.
@article{osti_20788295,
title = {Analysis of gene-expression profiles after gamma irradiation of normal human fibroblasts},
author = {Tachiiri, Seiji and Katagiri, Toyomasa and Tsunoda, Tatsuhiko and Oya, Natsuo and Hiraoka, Masahiro and Nakamura, Yusuke},
abstractNote = {Purpose: To understand comprehensive transcriptional profile of normal human fibroblast in response to irradiation. Methods and Materials: To identify genes whose expression is influenced by {gamma} radiation, we used a cDNA microarray to analyze expression of 23,000 genes in normal human fibroblasts at 7 timepoints (1, 3, 6, 12, 24, 48, and 72 hours) after 5 different doses (0.5, 2, 5, 15, and 50 Gy) of exposure. Results: Among the genes that showed altered expression patterns, some were already known to be regulated by irradiation, for instance ODC, EGR1, FGF2, PCNA, PKC, and several p53-target genes, including p53DINP1, BTG2, GADD45, and MDM2. The time course of each dose showed that from 350 to 600 genes were affected as to their expression; induction profiles characteristic to each dose were demonstrated. Of the total identified, only 89 genes were up-regulated; the vast majority was down-regulated over the 72-hour time course. We identified 21 genes that were distinctly induced by irradiation; 11 of them were functionally known, and 6 of those were p53-target genes. Conclusions: The results underscored the complexity of the transcriptional responses to irradiation, and the data should serve as a basis for global characterization of radiation-regulated genes and pathways.},
doi = {10.1016/J.IJROBP.2005.0},
journal = {International Journal of Radiation Oncology, Biology and Physics},
number = 1,
volume = 64,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2006},
month = {Sun Jan 01 00:00:00 EST 2006}
}
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