@misc{oai:repo.qst.go.jp:00069032,
 author = {Suetomi, Katsutoshi and Fujimori, Akira and Kubota, Yoshihisa and Takahashi, Sentaro and 末冨 勝敏 and 藤森 亮 and 久保田 善久 and 高橋 千太郎},
 month = {Jul},
 note = {In our previous study, we have indicated a novel expression
profiling method called 'high coverage expression profiling'
(HiCEP) could detect an alteration in gene expression as small as
1.5-fold and covers 70% to 80% of all transcripts. As HiCEP has a
great advantage over other common methods for detecting minimal
alterations in gene expression as described above, our comprehensive
approach using HiCEP method is thought to be a powerful
strategy to develop the system of risk assessment of many
chemicals.
Arsenic is one of the typical toxic metals and is also known to
be carcinogen. Exposure to arsenic is supposed to increase the risk
of occurrences of tumors (lung, skin, liver, bladder, and kidney). In
order to investigate the efficiency of HiCEP method on developing
the system of risk assessment of arsenic in the environment, we
carried out HiCEP analysis of human lung embryonic fibroblasts
(HFLIII) after 1 and 2 hours' exposure to 1 micro M sodium arsenite.
The most up-regulated gene is hemoxigenase 1 (HMOX1), which is
known to be induced by arsenic. We examined the effect of arsenic
on the HMOX1 expression by quantitative PCR (qPCR) after
several periods of incubation time with 1-10 micro M sodium arsenite.
HMOX1 expression reached to the peak value after 4 hours'
incubation with 1-10 micro M arsenic. We also examined the effect of
low level of arsenic on HMOX1 expression. HMOX1 expression
reached to the peak value after 2 hours' incubation with arsenic at
0.1 and 0.3 micro M, and after 4 hours' incubation with arsenic at 0.5
micro M. Up-regulation of HMOX1 gene was observed in HFLIII cells
treated with arsenic at 0.3 and 0.5 micro M. We examined the effect of
arsenic concentration on cell viability. Arsenic at less than 1 micro M
does hardly affect the viability of HFLIII cells.
We further explored the effect of ionizing radiation on
HMOX1 expression by qPCR 0.5, 2, and 4 hours after X-irradiation
at 2 and 4 Gy. At all of the period of time after X-irradiation at 2 and
4 Gy, HMOX1 expression was not up-regulated. In HiCEP analysis,
HMOX1 expression after low-dose X-irradiation was not upregulated
as well.
We conclude HiCEP could be used to develop the system of
risk assessment of many chemicals and HMOX1 could be a good
biomarker for arsenic contamination in the environment., 13th International Congress of Radiation Research},
 title = {Development of a risk assessment system of toxicants by HiCEP},
 year = {2007}
}