title: Optimization of an animal test protocol for toxicogenomics studies (I); requirement study of a protocol.
abstract: Toxicogenomics is a promising new tool for prediction of chemical toxicities including carcinogenicity in a relatively short period. However, it is important to develop a reliable animal test protocol for toxicogenomics studies. The preparation of RNA and tissues is also crucial, since it greatly influences outcomes of gene expression analysis. In the present study, we examined an animal test protocol by comparing gene expression data from different conditions and proposed a reliable animal test protocol for toxicogenomic studies. With regard to the preparation of tissues and RNA, here we present evidence that quality of RNA and tissues is well-preserved even after freezer storage for up to 2.5 years. Gene expression levels were compared using a GeneChip System (RGU34A, Affymetrix, Santa Clara, CA, USA) between RNA samples that were freshly prepared, stored at -80 degrees C or re-prepared from tissue kept at -20 degrees C. None showed degradation and no significant differences in expression were evident among the three sets of samples. The data demonstrate that gene expression analysis by DNA microarray is suitable for RNA or tissues that have been stored at an appropriate temperature.
authors.affiliation: Sumitomo Chemical Co., Ltd., 3-1-98 Kasugade-naka, Konohana-ku, Osaka 554-8558, Japan. sumida@sc.sumitomo-chem.co.jp
authors.forename: Kayo
authors.initials: K
authors.lastname: Sumida
authors.forename: Koichi
authors.initials: K
authors.lastname: Saito
authors.forename: Kenji
authors.initials: K
authors.lastname: Oeda
authors.forename: Masanori
authors.initials: M
authors.lastname: Otsuka
authors.forename: Kazunari
authors.initials: K
authors.lastname: Tsujimura
authors.forename: Hideki
authors.initials: H
authors.lastname: Miyaura
authors.forename: Masaru
authors.initials: M
authors.lastname: Sekijima
authors.forename: Koji
authors.initials: K
authors.lastname: Nakayama
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Kawano
authors.forename: Yuki
authors.initials: Y
authors.lastname: Kawakami
authors.forename: Makoto
authors.initials: M
authors.lastname: Asamoto
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Shirai
mesh_terms: D000818:Animals; D015197:Carcinogenicity Tests / Q000379:methods*; D020869:Gene Expression Profiling; D008297:Male; D020411:Oligonucleotide Array Sequence Analysis; D012313:RNA / Q000032:analysis; D051381:Rats; D012107:Research Design; D013048:Specimen Handling / Q000592:standards*; D013696:Temperature; D043922:Toxicogenetics / Q000379:methods*
chemical_list: D012313:RNA