title: Real-time gene expression analysis in human xenografts for evaluation of histone deacetylase inhibitors.
abstract: Real-time analysis of gene expression in experimental tumor models represents a major tool to document disease biology and evaluate disease treatment. However, monitoring gene regulation in vivo still is an emerging field, and thus far it has not been linked to long-term tumor growth and disease outcome. In this report, we describe the development and validation of a fluorescence-based gene expression model driven by the promoter of the cyclin-dependent kinase inhibitor p21waf1,cip1. The latter is a key regulator of tumor cell proliferation and a major determinant in the response to many anticancer agents such as histone deacetylase inhibitors. In response to histone deacetylase inhibitors, induction of fluorescence in A2780 ovarian tumors could be monitored in living mice in a noninvasive real-time manner using whole-body imaging. Single p.o. administration of the histone deacetylase inhibitor MS-275 significantly induces tumor fluorescence in a time- and dose-dependent manner, which accurately predicted long-term antitumoral efficacy in individual mice following extended treatment. These findings illustrate that this technology allows monitoring of the biological response induced by treatment with histone deacetylase inhibitors. In addition to providing experimental pharmacokinetic/pharmacodynamic markers for investigational drugs, this model provides insight into the kinetics of in vivo regulation of transcription, which plays a key role in causing and maintaining the uncontrolled proliferation of tumor tissue.
authors.affiliation: Oncology Discovery Research and Early Development, Johnson & Johnson Pharmaceutical Research and Development, Turnhoutseweg 30, 2340 Beerse, Belgium.
authors.forename: Ann
authors.initials: A
authors.lastname: Beliën
authors.forename: Stefanie
authors.initials: S
authors.lastname: De Schepper
authors.forename: Wim
authors.initials: W
authors.lastname: Floren
authors.forename: Boud
authors.initials: B
authors.lastname: Janssens
authors.forename: Ann
authors.initials: A
authors.lastname: Mariën
authors.forename: Peter
authors.initials: P
authors.lastname: King
authors.forename: Jacky
authors.initials: J
authors.lastname: Van Dun
authors.forename: Luc
authors.initials: L
authors.lastname: Andries
authors.forename: Jan
authors.initials: J
authors.lastname: Voeten
authors.forename: Luc
authors.initials: L
authors.lastname: Bijnens
authors.forename: Michel
authors.initials: M
authors.lastname: Janicot
authors.forename: Janine
authors.initials: J
authors.lastname: Arts
mesh_terms: D000818:Animals; D050759:Cyclin-Dependent Kinase Inhibitor p21 / Q000235:genetics; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D005260:Female; D015870:Gene Expression; D017930:Genes, Reporter; D049452:Green Fluorescent Proteins / Q000235:genetics; D056572:Histone Deacetylase Inhibitors; D006655:Histone Deacetylases / Q000378:metabolism; D006801:Humans; D008297:Male; D051379:Mice; D008819:Mice, Nude; D010051:Ovarian Neoplasms / Q000188:drug therapy* / Q000201:enzymology / Q000235:genetics* / Q000473:pathology; D011401:Promoter Regions, Genetic; D023041:Xenograft Model Antitumor Assays / Q000379:methods*
chemical_list: C493956:CDKN1A protein, human; D050759:Cyclin-Dependent Kinase Inhibitor p21; D004791:Enzyme Inhibitors; D056572:Histone Deacetylase Inhibitors; D049452:Green Fluorescent Proteins; D006655:Histone Deacetylases