title: Liver gene expression profiles of rats treated with clofibric acid: comparison of whole liver and laser capture microdissected liver.
abstract: Clofibric acid (CLO) is a peroxisome proliferator (PP) that acts through the peroxisome proliferator activated receptor alpha, leading to hepatocarcinogenesis in rodents. CLO-induced hepatocarcinogenesis is a multi-step process, first transforming normal liver cells into foci. The combination of laser capture microdissection (LCM) and genomics has the potential to provide expression profiles from such small cell clusters, giving an opportunity to understand the process of cancer development in response to PPs. To our knowledge, this is the first evaluation of the impact of the successive steps of LCM procedure on gene expression profiling by comparing profiles from LCM samples to those obtained with non-microdissected liver samples collected after a 1 month CLO treatment in the rat. We showed that hematoxylin and eosin (H&E) staining and laser microdissection itself do not impact on RNA quality. However, the overall process of the LCM procedure affects the RNA quality, resulting in a bias in the gene profiles. Nonetheless, this bias did not prevent accurate determination of a CLO-specific molecular signature. Thus, gene-profiling analysis of microdissected foci, identified by H&E staining may provide insight into the mechanisms underlying non-genotoxic hepatocarcinogenesis in the rat by allowing identification of specific genes that are regulated by CLO in early pre-neoplastic foci.
authors: Department of Drug Safety Evaluation, Aventis Pharma, Vitry-sur-Seine, France.
authors: Cécile
authors: C
authors: Michel
authors: Chantal
authors: C
authors: Desdouets
authors: Béatrice
authors: B
authors: Sacre-Salem
authors: Jean-Charles
authors: JC
authors: Gautier
authors: Ruth
authors: R
authors: Roberts
authors: Eric
authors: E
authors: Boitier
mesh_terms: D000818:Animals; D002995:Clofibric Acid / Q000008:administration & dosage / Q000494:pharmacology*; D004210:Dissection; D004305:Dose-Response Relationship, Drug; D015870:Gene Expression / Q000187:drug effects*; D020869:Gene Expression Profiling; D007834:Lasers; D008099:Liver / Q000187:drug effects* / Q000473:pathology / Q000502:physiology*; D008297:Male; D012313:RNA / Q000737:chemistry / Q000378:metabolism; D051381:Rats; D011916:Rats, Inbred F344; D015203:Reproducibility of Results; D013194:Staining and Labeling
chemical_list: D002995:Clofibric Acid; D012313:RNA