BACKGROUND: Current urine-based assays for bladder cancer (BCa) diagnosis lack 
accuracy, so the search for improved biomarkers continues. Through genomic and 
proteomic profiling of urine, we have identified a panel of biomarkers 
associated with the presence of BCa. In this study, we evaluated the utility of 
three of these biomarkers, interleukin 8 (IL-8), Matrix metallopeptidase 9 
(MMP-9) and Syndecan in the diagnosis of BCa through urinalysis.
METHODS: Voided urines from 127 subjects, cancer subjects (n = 64), non-cancer 
subjects (n = 63) were analyzed. The protein concentrations of IL-8, MMP-9, and 
Syndecan were assessed by enzyme-linked immunosorbent assay (ELISA). Data were 
also compared to a commercial ELISA-based BCa detection assay (BTA-Trak©) and 
urinary cytology. We used the area under the curve of a receiver operating 
characteristic (AUROC) to compare the performance of each biomarker.
RESULTS: Urinary protein concentrations of IL-8, MMP-9 and BTA were 
significantly elevated in BCa subjects. Of the experimental markers compared to 
BTA-Trak©, IL-8 was the most prominent marker (AUC; 0.79; 95% confidence 
interval [CI], 0.72-0.86). Multivariate regression analysis revealed that only 
IL-8 (OR; 1.51; 95% CI, 1.16-1.97, p = 0.002) was an independent factor for the 
detection of BCa.
CONCLUSIONS: These results suggest that the measurement of IL-8 in voided 
urinary samples may have utility for urine-based detection of BCa. These 
findings need to be confirmed in a larger, prospective cohort.