Evaluation of urinary proepithelin as a potential biomarker for bladder cancer detection and prognosis in Egyptian patients

Proepithelin is a growth factor that may play a critical role in bladder cancer. Its over-expression in urine of bladder cancer patients gave us the impetus to evaluate its potential suitability as a biomarker for bladder cancer diagnosis and/or prognosis. proepithelin was estimated in 86 voided urine samples, including 59 bladder cancer patients and 27 healthy volunteers using quantitative sandwich enzyme immunoassay technique. Urinary proepithelin level was expressed in ng/100 mg creatinine. Urinary proepithelin was significantly higher in bladder cancer patients compared to control subjects (means: 17.5 ± 10 and 8.9 ± 3.5 ng/100 mg creatinine, respectively; p < 0.001), and the test sensitivity and specificity to detect the presence of bladder cancer were 74.6 and 85.2%, respectively. Furthermore, patients with low-grade/non-muscle invasive stages bladder cancer showed significantly lower urinary proepithelin compared to high-grade/non-muscle invasive stages and high-grade/invasive stages ones (means: 11.6 ± 9, 20.2 ± 8.1 and 23.8 ± 11.9 ng/100 mg creatinine, respectively; p= 0.005 and 0.002, respectively). This preliminary study suggests that urinary proepithelin may be considered as a non-invasive, sensitive, and specific urine-based test for bladder cancer diagnosis and/or prognosis.