Renal obstruction, or ureteropelvic junction obstruction (UPJO), can result in loss of kidney function and abnormal renal maturation. Appropriate early surgical intervention may prevent renal damage. The clinical dilemma is identifying which children need intervention and when. Renal obstruction always results in hydronephrosis, or dilation of the kidney; however, hydronephrosis does not always indicate clinically significant obstruction. To further compound the quandary, up to 5% of all pregnancies have a diagnosis of prenatal hydronephrosis, in which 30% may be caused by UPJO. This considerably increases the number of children who may need screening after birth. Current diagnostics are constrained to imaging modalities that are invasive, expose the children to ionizing radiation, may require general anesthesia, and are limited by their subjective nature. Although excellent surgical treatment exists, there are (1) NO definitive clinical tests that determine who with hydronephrosis requires surgery; (2) NO established clinical guidelines for postnatal diagnostic testing or intervention; and (3) NO ability to determine who is at risk for future long-term renal damage. A more accurate non-invasive test to standardize clinical guidelines, diagnosis, and management is sorely needed. Using a mass spectrometry (MS) based method developed in our laboratory; we identified a candidate list of 76 potential urinary biomarkers of UPJO from over 1114 proteins identified in an unbiased quantitative discovery study of the obstructed urinary proteome. Interestingly, there was a particular subset of proteins (24) involved with oxidative stress that had dramatic quantitative fold differences in the urine. I addition, data generated from an additional cohort identified a potential role of urinary matrix metalloproteinases (MMP) as a clinical biomarker for UPJO. Our data suggests that there are specific urinary biomarkers that have the potential to determine which children with hydronephrosis require surgical intervention for UPJO. In this proposal we present the first rigorous early-validation trial of candidate urinary markers as diagnostic tools for UPJO. We hypothesize that the urinary proteome of children with UPJO contains clinically useful biomarkers of renal obstruction that will non-invasively determine which children should undergo surgical intervention versus observation. We will challenge this hypothesis with the following specific aims: 1) Identify the best panel of markers in noninvasively obtained urine from the bladder of UPJO patients using directed MS and MMP profiling. 2) Determine if the best panel of UPJO markers allows for stratification of patients with hydronephrosis in a longitudinal mixed disease cohort. These studies are specifically designed to pre-validate urinary biomarkers that have the potential to significantly alter and improve the clinical management of a very large population of children with hydronephrosis. The findings of these highly translational experiments may be the basis for a prospective clinical trial.

Public Health Relevance

Renal obstruction, or ureteropelvic junction obstruction (UPJO), can result in loss of kidney function and abnormal renal maturation, and is the most common cause of renal failure in children. Appropriate early surgical intervention may prevent renal damage. The clinical dilemma is identifying which children need intervention and when. Renal obstruction always results in hydronephrosis, or dilation of the kidney; however, hydronephrosis does not always indicate clinically significant obstruction. Although excellent surgical treatment exists, there are no definitive clinical tests that determine who with hydronephrosis requires surgery. Our data suggests that there are specific proteins in the urine that have the potential to determine which children with hydronephrosis require surgical intervention for UPJO. Our approach has evolved from discovery-based studies to directed validation. Our primary goal is to determine the best panel of markers in noninvasively obtained urine from the bladder that can identify which children with hydronephrosis require surgical intervention versus observation.

Agency
National Institute of Health (NIH)
Institute
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Type
Research Project (R01)
Project #
5R01DK096238-05
Application #
9257415
Study Section
Urologic and Genitourinary Physiology and Pathology (UGPP)
Program Officer
Mendley, Susan Ruth
Project Start
2013-07-01
Project End
2019-04-30
Budget Start
2017-05-01
Budget End
2019-04-30
Support Year
5
Fiscal Year
2017
Total Cost
Indirect Cost
Name
Boston Children's Hospital
Department
Type
DUNS #
076593722
City
Boston
State
MA
Country
United States
Zip Code
02115
van der Ven, Amelie T; Connaughton, Dervla M; Ityel, Hadas et al. (2018) Whole-Exome Sequencing Identifies Causative Mutations in Families with Congenital Anomalies of the Kidney and Urinary Tract. J Am Soc Nephrol 29:2348-2361
Forster, Catherine S; Johnson, Kathryn; Patel, Viral et al. (2017) Urinary NGAL deficiency in recurrent urinary tract infections. Pediatr Nephrol 32:1077-1080
Kohl, Stefan; Chen, Jing; Vivante, Asaf et al. (2016) Targeted sequencing of 96 renal developmental microRNAs in 1213 individuals from 980 families with congenital anomalies of the kidney and urinary tract. Nephrol Dial Transplant 31:1280-3
Froehlich, John W; Kostel, Stephen A; Cho, Patricia S et al. (2016) Urinary Proteomics Yield Pathological Insights for Ureteropelvic Junction Obstruction. Mol Cell Proteomics 15:2607-15
Zhou, Hui; Morley, Samantha; Kostel, Stephen et al. (2016) Universal Solid-Phase Reversible Sample-Prep for Concurrent Proteome and N-Glycome Characterization. J Proteome Res 15:891-9
Vivante, Asaf; Kleppa, Marc-Jens; Schulz, Julian et al. (2015) Mutations in TBX18 Cause Dominant Urinary Tract Malformations via Transcriptional Dysregulation of Ureter Development. Am J Hum Genet 97:291-301
Froehlich, John W; Vaezzadeh, Ali R; Kirchner, Marc et al. (2014) An in-depth comparison of the male pediatric and adult urinary proteomes. Biochim Biophys Acta 1844:1044-50
Zhou, Hui; Warren, Peter G; Froehlich, John W et al. (2014) Dual modifications strategy to quantify neutral and sialylated N-glycans simultaneously by MALDI-MS. Anal Chem 86:6277-84
Froehlich, John W; Dodds, Eric D; Wilhelm, Mathias et al. (2013) A classifier based on accurate mass measurements to aid large scale, unbiased glycoproteomics. Mol Cell Proteomics 12:1017-25
Serang, Oliver; Froehlich, John W; Muntel, Jan et al. (2013) SweetSEQer, simple de novo filtering and annotation of glycoconjugate mass spectra. Mol Cell Proteomics 12:1735-40

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