title: Urinary podocyte excretion and proteinuria in patients treated with antivascular endothelial growth factor therapy for solid tumor malignancies.
abstract: BACKGROUND
  Urinary podocyte excretion (podocyturia) may function as a more specific marker of ongoing glomerular damage. This study sought to analyze the relationship between proteinuria and podocyturia in cancer patients treated with antivascular endothelial growth factor (anti-VEGF) agents.
  
  
  METHODS
  Thirty-seven patients treated with anti-VEGF medications were analyzed in a single-institution, cross-sectional study. Podocyte cultures were performed on random urine collections (50-100 ml), and podocytes were identified by positive podocin staining. The corresponding urine samples were analyzed for protein and creatinine (Cr) measurements.
  
  
  RESULTS
  Proteinuria ≥0.5 g/g Cr was found in 30% of the patients (median, 0.12; interquartile range, 0.04-0.86), and 62% had podocyturia. There was a significant difference in the amount of podocyturia between patients with proteinuria ≥0.5 g/g Cr and those with a value <0.5 g/g Cr (median podocyturia, 1.08 cells/mg Cr, range, 0-14.55 vs. 0.03 cells/mg Cr, range, 0-1.64, respectively; p < 0.001). A statistically significant correlation was observed between the cumulative dose of bevacizumab and both proteinuria (r = 0.48, p = 0.004) and podocyturia (r = 0.34, p = 0.045) as well as between proteinuria and podocyturia (r = 0.63, p < 0.001), suggesting that these are mechanistically related.
  
  
  CONCLUSIONS
  Ongoing podocyte loss may be mechanistically related to the onset and severity of proteinuria in patients treated with anti-VEGF agents.
authors.affiliation: Division of Hematology, Mayo Clinic, Rochester, Minn., USA.
authors.forename: Suzanne R
authors.initials: SR
authors.lastname: Hayman
authors.forename: Juan C
authors.initials: JC
authors.lastname: Calle
authors.forename: Aminah
authors.initials: A
authors.lastname: Jatoi
authors.forename: Iasmina M
authors.initials: IM
authors.lastname: Craici
authors.forename: Steven J
authors.initials: SJ
authors.lastname: Wagner
authors.forename: Amy L
authors.initials: AL
authors.lastname: Weaver
authors.forename: Eddie L
authors.initials: EL
authors.lastname: Greene
authors.forename: Joseph P
authors.initials: JP
authors.lastname: Grande
authors.forename: Vesna D
authors.initials: VD
authors.lastname: Garovic
mesh_terms: D000328:Adult; D000368:Aged; D061067:Antibodies, Monoclonal, Humanized / Q000009:adverse effects* / Q000627:therapeutic use; D000970:Antineoplastic Agents / Q000009:adverse effects* / Q000627:therapeutic use; D000068258:Bevacizumab; D005260:Female; D005770:Gastrointestinal Neoplasms / Q000188:drug therapy* / Q000401:mortality; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D050199:Podocytes / Q000187:drug effects / Q000473:pathology*; D011507:Proteinuria / Q000139:chemically induced / Q000473:pathology*; D042461:Vascular Endothelial Growth Factor A / Q000037:antagonists & inhibitors
chemical_list: D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents; C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A; D000068258:Bevacizumab