Low- and high-grade bladder cancer appraisal via serum-based proteomics approach.

Objective: To address the shortcomings of urine cytology and cystoscopy for screening and grading of urinary bladder cancer (BC) we applied a serum-based proteomics approach as a surrogate tactic for rapid BC probing.

Methods: This study was performed on 90 sera samples comprising of low-grade (LG, n=33) and high-grade (HG, n=32) BC, and healthy controls (HC, n=25). Two-dimensional gel electrophoresis (2DE) tactic was executed to describe serum proteome. MALDI-TOF-MS (MS) was used to identify the characteristics of aberrantly expressed proteins in 2DE and validated using Western blot (WB) and ELISA approach. Receiver operating characteristics (ROC) curve analysis was also performed to determine the clinical usefulness of these proteins to discriminate among LG, HG and HC cohorts.

Results: This comprehensive approach of 2DE, MS, WB and ELISA reveals five differentially expressed proteins. Among them two biomarkers (S100A8 and S100A9) were able to accurately (ROC, 0.946) distinguish 81% of BC (LG+HG) cases compared to HC with highest sensitivity and specificity. With a comparable tactic, two biomarkers (S100A8 and S100A4) were able to precisely (ROC, 0.941) discriminate 92% of LG cases from HG with utmost sensitivity and specificity.

Conclusions: Serum proteomics probing appears to be an encouraging and least-invasive tactic for screening and grading of BC.