Comparison of APF activity and epithelial growth factor levels in urine from Chinese, African-American, and white American patients with interstitial cystitis.
OBJECTIVE
Interstitial cystitis (IC) is a chronic bladder disorder for which the etiology is unknown. We have previously shown that antiproliferative factor (APF), heparin-binding epidermal growth factor-like growth factor (HB-EGF), and epidermal growth factor (EGF) are sensitive and specific biomarkers for IC in white American patients. Because little is known about the epidemiology of this disorder, it is unclear whether these factors would also be useful biomarkers for IC in patients from different racial groups and/or geographic locations.


METHODS
Urine specimens were collected from Chinese, white American, and African-American women with IC and age and race-matched asymptomatic normal control women. APF activity was determined by (3)H-thymidine incorporation into primary normal adult human bladder epithelial cells in vitro. The HB-EGF and EGF urine levels were determined by enzyme-linked immunosorbent assay.


RESULTS
The Chinese, African-American, and white American women with IC had significantly greater urine APF activity (P <0.000001, P = 0.0008, and P <0.000001, respectively), lower urine HB-EGF levels (P <0.000001, P = 0.02, and P <0.000001, respectively), and greater urine EGF levels (P <0.000001, P = 0.002, and P <0.000001, respectively), than their matched asymptomatic controls.


CONCLUSIONS
These findings confirm the utility of APF, HB-EGF, and EGF as biomarkers for IC in patients from three different racial groups and two different countries.
Division of Infectious Diseases, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland, USA.
Chen-O
CO
u Zhang
Ze-Liang
ZL
Li
Joanna L
JL
Shoenfelt
Chui-Ze
CZ
Kong
Toby C
TC
Chai
Deborah R
DR
Erickson
Kenneth M
KM
Peters
Eric S
ES
Rovner
Susan
S
Keay
D000328:Adult; D044466:Asian People; D015415:Biomarkers / Q000652:urine; D044383:Black People; D002478:Cells, Cultured; D018856:Cystitis, Interstitial / Q000208:ethnology* / Q000652:urine*; D004815:Epidermal Growth Factor / Q000652:urine*; D005260:Female; D006131:Growth Inhibitors / Q000652:urine*; D066257:Heparin-binding EGF-like Growth Factor; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins; D008875:Middle Aged; D013936:Thymidine / Q000378:metabolism; D014316:Tritium / Q000378:metabolism; D001743:Urinary Bladder / Q000737:chemistry / Q000473:pathology; D044465:White People; D001741:Black or African American
D015415:Biomarkers; D006131:Growth Inhibitors; C587883:HBEGF protein, human; D066257:Heparin-binding EGF-like Growth Factor; D036341:Intercellular Signaling Peptides and Proteins; D014316:Tritium; D004815:Epidermal Growth Factor; D013936:Thymidine