This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Cheng, J. Articles by Wu, X.-R. Search for Related Content PubMed PubMed Citation Articles by Cheng, J. Articles by Wu, X.-R.

Allelic Loss of p53 Gene Is Associated with Genesis and Maintenance, but not Invasion, of Mouse Carcinoma in Situ of the Bladder¹

Departments of Urology [J. C., H. H., E. S., T-T. S., X-R. W.], Microbiology [X-R. W.], Dermatology [T-T. S.], and Pharmacology [T-T. S.], Kaplan Comprehensive Cancer Center, New York University School of Medicine, New York, New York 10016; Veteran Affairs Medical Center in New York, New York 10010 [J. P., X-R. W.]; Division of Molecular Pathology, Memorial Sloan-Kettering Cancer Center, New York, New York 10021 [C. C-C.]; and Cancer Center and Department of Urology, University of California San Francisco, San Francisco, California 94143 [F. M. W.]

Carcinoma in situ (CIS) of the bladder has recently been proposed to be a heterogeneous group of diseases with varied histogenesis and biological behavior. In this study, we describe the sequential steps of CIS development and progression in a transgenic mouse model expressing low levels of the SV40 large T antigen. We found that CIS in transgenic mice arose from urothelial dysplasia, that CIS could persist for an extended period of time without invasion, and that the majority of CIS eventually evolved into high-grade, superficial, papillary tumors before a small fraction of them advanced to invasion/metastasis. A genome-wide search of chromosomal imbalances by comparative genomic hybridization revealed that 9 of 11 (82%) of CIS had losses on chromosome 11. Southern blotting demonstrated the allelic loss of the p53 gene, which resides on mouse chromosome 11, in four comparative genomic hybridization-tested tumors and 10 of 11 (91%) additional CIS examined. Consistent with the reduced p53 gene dosage because of the allelic loss and the functional inactivation of p53 protein of the remaining allele by SV40T antigen, there was a dramatic decrease in CIS of Mdm-2, a major p53 target. In contrast, the level of p21, another p53 target, was largely unaltered, suggesting that p21 expression can be regulated by p53-independent mechanisms. These results delineate the early stages of bladder tumorigenesis and suggest that the loss of a p53-bearing chromosome is an early event in bladder tumorigenesis and is crucial for the genesis and the maintenance, but not the progression, of bladder CIS. On the basis of our current and previous transgenic studies, we have proposed an integrated pathway progression model of bladder cancer.

This article has been cited by other articles:

				K. Iida, K. Itoh, J. M. Maher, Y. Kumagai, R. Oyasu, Y. Mori, T. Shimazui, H. Akaza, and M. Yamamoto Nrf2 and p53 cooperatively protect against BBN-induced urinary bladder carcinogenesis Carcinogenesis, November 1, 2007; 28(11): 2398 - 2403. [Abstract] [Full Text] [PDF]

				R.A. Crallan, N.T. Georgopoulos, and J. Southgate Experimental models of human bladder carcinogenesis Carcinogenesis, March 1, 2006; 27(3): 374 - 381. [Abstract] [Full Text] [PDF]

				A. Garcia-Espana, E. Salazar, T.-T. Sun, X.-R. Wu, and A. Pellicer Differential Expression of Cell Cycle Regulators in Phenotypic Variants of Transgenically Induced Bladder Tumors: Implications for Tumor Behavior Cancer Res., February 15, 2005; 65(4): 1150 - 1157. [Abstract] [Full Text] [PDF]