Quantitative Urinary Proteome Reveals Potential Biomarkers for Ureteropelvic Junction Obstruction

Purpose: Ureteropelvic junction obstruction (UPJO) is a common obstructive disease. To investigate useful urinary biomarkers in UPJO children, the urinary proteome in UPJO infants is analyzed and it is compared with normal controls.

Experimental design: A tandem mass tag (TMT)-based quantitative proteomics study is performed to analyze the proteome of bladder urine (BU) and pelvis urine (PU) from unilateral UPJO infants with differential renal function less than 40% and they are compared with normal control urine (CON). GO analysis is then utilized to analyze general characterization of the proteins. Proteomic results are verified by western blot.

Results: There are 81 and 186 proteins significantly changed in BU and PU groups, respectively, as compared to the CON group. Fifty proteins overlaps are found between these two sets of statistically significant differential proteins. These 50 common differential proteins are involved in multiple biological processes. The increased urinary abundance of Fetuin-A, AGP1, AGP2, Alpha-1-microglobulin/Bikunin Precursor (AMBP), and prostaglandin-H2D-isomerase (PGDS) are verified by western blot analysis.

Conclusions and clinical relevance: This proteomic analysis indicates that urinary Fetuin-A, AGP1, AGP2, protein AMBP, and PGDS may serve as noninvasive potential biomarkers and these proteins can help to further yield pathological mechanisms involved in UPJO.