title: Measurement of beta-galactosidase tissue levels in a tumor cell xenograft model.
abstract: The nude mouse xenograft model is commonly used to examine the growth and development of human cancer cells in vivo. Tumor cells transfected with the Lac-Z reporter gene for beta-galactosidase (beta-gal) enzyme activity can be used to quantify tumor and metastatic development in this model. The present study was designed to develop methodology to accurately measure beta-gal in tumor and tissue samples from a nude mouse model. In this study, we developed tissue extraction procedures and compared the sensitivity and accuracy of o-nitrophenyl-beta-D-galactopyranoside (ONPG) and chlorophenol red beta-D-galactopyranoside (CPRG); two beta-gal substrates. Our results demonstrated that the CPRG substrate is more sensitive and accurate in the measurement of beta-gal activity than the ONPG substrate. In addition, matrices and blood in tissue samples are less likely to interfere with the CPRG assay. We concluded that the CPRG substrate-based assay represents a reliable technique for the determination of beta-gal activity in transfected cancer cells present in tumor and tissue specimens from the nude mouse xenograft model.
authors.affiliation: Department of Pharmaceutical Sciences, University of Oklahoma Health Sciences Center, Oklahoma City, USA.
authors.forename: C J
authors.initials: CJ
authors.lastname: Buller
authors.forename: X-P
authors.initials: XP
authors.lastname: Zang
authors.forename: E W
authors.initials: EW
authors.lastname: Howard
authors.forename: J T
authors.initials: JT
authors.lastname: Pento
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D003124:Colorimetry / Q000379:methods; D005260:Female; D006801:Humans; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D014018:Tissue Distribution / Q000502:physiology; D023041:Xenograft Model Antitumor Assays / Q000379:methods*; D001616:beta-Galactosidase / Q000032:analysis* / Q000378:metabolism
chemical_list: D001616:beta-Galactosidase