A human ovarian carcinoma murine xenograft model useful for preclinical trials

Objective. To establish a murine xenograft model of human ovarian carcinoma. Methods. A slurry of fresh human tumor from patients with intraperitoneal malignancies was heterotransplanted intraperitoneally into nude (nu/nu) and severely combined immunodeficient mice (CB-17, SCID). Xenograft growth was assessed by serial examination and necropsy. The xenografts were passaged to new animals when tumors were palpably greater than 1 cm(3). Histopathologic analysis of the xenografts was performed at each passage as well as immunohistochemical staining for p53 mutations. Persistent expression of human genes by the xenografts at higher passages was assessed by RT-PCR amplification of the human beta-globin gene. This xenograft model was used in the preclinical evaluation of an adenoviral vector containing a beta-galactosidase reporter gene and a wild-type p53 gene. Results. Tumor growth was not established in any of the nude mice heterotransplanted with tissue from six different ovarian cancer patients. Eleven of 13 specimens established xenograft growth when injected in SCID mice. Nine xenografts have been subsequently passaged between 6 and 24 animal generations to date. All xenografts retained histopathologic similarities to their original human tumors and the p53 expression patterns remained stable through higher passages. Within 24 h after intraperitoneal administration of an adenoviral vector, transduction of the reporter gene was evident in the xenografts. In addition, administration of an adenoviral vector containing a wild-type p53 gene significantly decreased the tumor burden compared to controls (P < 0.04). Conclusions. This murine xenograft model of human ovarian carcinoma appears to be reliable and reproducible and has utility for the study of novel therapeutics. (C) 2002 Elsevier Science (USA).