title: Gene expression analysis of urine sediment: evaluation for potential noninvasive markers of interstitial cystitis/bladder pain syndrome.
abstract: OBJECTIVE
  We determined whether gene expression profiles in urine sediment could provide noninvasive markers for interstitial cystitis/bladder pain syndrome with and/or without Hunner lesions.
  
  
  METHODS
  Fresh catheterized urine was collected and centrifuged from 5 controls, and 5 Hunner lesion-free and 5 Hunner lesion bearing patients. RNA was extracted from pelleted material and quantified by gene expression microarray using the GeneChip® Human Gene ST Array. Three biologically likely hypotheses were tested, including 1) all 3 groups are distinct from each other, 2) controls are distinct from the 2 types combined of patients with interstitial cystitis/bladder pain syndrome and 3) patients with Hunner lesion-interstitial cystitis/bladder pain syndrome are distinct from controls and patients with nonHunner-lesion interstitial cystitis/bladder pain syndrome combined. For statistical parity an unlikely fourth hypothesis was included, that is patients with nonHunner-lesion interstitial cystitis/bladder pain syndrome are distinct from controls and patients with Hunner lesion-interstitial cystitis/bladder pain syndrome combined.
  
  
  RESULTS
  Analysis supported selective up-regulation of genes in the Hunner lesion interstitial cystitis/bladder pain syndrome group (hypothesis 3), which were primarily associated with inflammation. The inflammatory profile was statistically similar to that reported in a prior Hunner lesion interstitial cystitis/bladder pain syndrome bladder biopsy study.
  
  
  CONCLUSIONS
  Gene expression analysis of urine sediment was feasible in this pilot study. Expression profiles failed to discriminate nonHunner-lesion interstitial cystitis/bladder pain syndrome from controls and they are unlikely to be a noninvasive marker for nonHunner-lesion interstitial cystitis/bladder pain syndrome. In contrast, patients with Hunner lesion had increased proinflammatory gene expression in urine sediment, similar to that in a prior microarray study of bladder biopsies. If these preliminary results are validated in future research, they may lead to a noninvasive biomarker for Hunner lesion-interstitial cystitis/bladder pain syndrome.
authors.affiliation: Department of Molecular and Biomedical Pharmacology, University of Kentucky, Lexington, KY, USA.
authors.forename: Eric M
authors.initials: EM
authors.lastname: Blalock
authors.forename: Garrett S
authors.initials: GS
authors.lastname: Korrect
authors.forename: Arnold J
authors.initials: AJ
authors.lastname: Stromberg
authors.forename: Deborah R
authors.initials: DR
authors.lastname: Erickson
mesh_terms: D000328:Adult; D000368:Aged; D018856:Cystitis, Interstitial / Q000235:genetics* / Q000652:urine*; D005260:Female; D020869:Gene Expression Profiling; D005819:Genetic Markers; D006801:Humans; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects
chemical_list: D005819:Genetic Markers