A. Using a recently developed metastasis model that we have analyzed by microarray (32), we found significantly higher Ral signature scores in metastatic Lul2 cells compared to parental Luc cells. B. Using microarray data from a recent publication where cells with stem cell-like properties were isolated from bladder cancer cells by cell sorting (51), we found significantly higher Ral signature scores in these cells compared to parental or negative sorted cells (Mann-Whitney, plot shows median plus 95% CI). C. In the Sanchez Carbayo et al. cohort of 91 bladder cancers used in Figure 2A-B, the Ral signature score was associated with overall survival (Kaplan-Meier plot showing signature score >0.5 high versus <0.5 low, Log Rank test). D. In non-muscle invasive tumors, expression of the Ral signature is significantly associated with subsequent progression to muscle invasion in a previously published cohort (N=29) (33) (Kaplan-Meier plot and Log Rank test to C.).