Abstract A16: DNA microarray analysis of the UPII‐SV40Tag model for invasive bladder TCC: Identification of markers for bladder premalignancy

Transitional cell carcinoma of the bladder (TCC) ranks 4th in incidence of all cancers in the developed world, yet the mechanisms of its origin and progression remain poorly understood. There are a few commercially available urine‐based tests for screening and surveillance for bladder cancer, but none of these can detect premalignancy. We have combined a transgenic mouse model for invasive bladder cancer (UPII‐SV40Tag mice) with DNA microarray technology, in order to determine molecular mechanisms involved in early TCC development and to identify new biomarkers for detection, diagnosis and prognosis of TCC. We have identified genes that are differentially expressed between the bladders of UPII‐SV40Tag mice and their age‐matched wild type (WT) littermates at 3, 6, 20 and 30 weeks of age. These are ages which correspond to premalignant, carcinoma in‐situ, and early and later stage papillary TCC, respectively. There were approximately 1,900 unique genes differentially expressed (>= 3‐fold difference at one or more time points) between WT and UPII‐SV40Tag urothelium during the time course of tumor development. Among these, there were a high proportion of cell cycle regulatory genes and proliferation signaling genes that are more strongly expressed in the UPII‐SV40Tag bladder urothelium. We have tested several of the genes upregulated in UPII‐SV40Tag urothelium, including autocrine motility factor (AMFR), hyaluronan‐mediated motility receptor (Hmmr), proliferating cell nuclear antigen (PCNA), Rac GTPase activating protein 1 (RacGAP 1) and others as biomarkers for premalignancy, in urine samples from a recently completed Phase II, randomized, placebo controlled chemoprevention trial (N01 CN85186, PI: A. Sabichi) that was designed to test whether celecoxib can prevent recurrence in patients successfully treated by TUR for non‐muscle invasive bladder cancer. Citation Information: Cancer Prev Res 2010;3(1 Suppl):A16.